Human skeletal anatomy : laboratory manual and workbook 9780398072025, 0398072027

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HUMAN SKELETAL ANATOMY

ABOUT THE AUTHORS

Dr. Scott I. Fairgrieve, Ph.D. Forensic Osteologist, Forensic Biology Option Head and Director of the Forensic Osteology Laboratory Anthropology Program and Department of Biology Laurentian University, Sudbury, Ontario, Canada Dr. Fairgrieve received his B.Sc. (Hon.) in Anthropology from the University of Toronto at Mississauga (Erindale College) in 1986. In 1987, he received an M.Phil. in Biological Anthropology from the University of Cambridge, England. Subsequently, he studied under Dr. Jerry Melbye at the University of Toronto, receiving his Ph.D. in Anthropology (specializing in human skeletal biology) in 1993. Since 1991, Dr. Fairgrieve has been a member of the faculty at Laurentian University and is cross-appointed between the Anthropology Program and the Department of Biology as a tenured Associate Professor. Dr. Fairgrieve is a member of the Canadian Society of Forensic Science, Canadian Identification Society and a Fellow of the American Academy of Forensic Sciences. Dr. Fairgrieve is a consultant to various law enforcement services in Northern Ontario. Dr. Fairgrieve's research has centered on biochemical analysis of Romano Christian human skeletons from the Dakhleh Oasis, Egypt. More recently, Dr. Fairgrieve's research has concentrated on problems of determining age at death and the postmortem interval of human skeletons. He is also head of the only Forensic Biology Option within a Biology Program in Canada. Ms. Tracy S. Oost, H.B.A., H.B.Sc., M.Sc. (Cand.) Laboratory Manager Forensic Osteology Laboratory Department of Biology Laurentian University, Sudbury, Ontario, Canada Ms. Tracy Oost received her B.A. (Hon.) and B.Sc. (Hon.) in Anthropology and Biology, respectively, from Laurentian University in 1996. Ms. Oost is an M.Sc. candidate in the Department of Biology at Laurentian University. Her thesis research is centered on the application of bone citrate levels as a means of estimating postmortem intervals in mammalian species. Currently, she teaches courses in Human Anatomy and Physiology, Basic Pharmacology, and Chronic Diseases. Ms. Oost is a member of the Canadian Identification SOCiety, Canadian Society of Forensic Science and the American Academy of Forensic Sciences. Additionally, Ms. Oost is the Manager of the Forensic Osteology Laboratory at Laurentian University. Her work also involves scene documentation and collection of evidence with police personnel in a forensic casework setting. Ms. Oost has been involved in running laboratories for educating students in human anatomy and physiology, human skeletal anatomy and forensic biology.

HUMAN SKELETAL ANATOMY Laboratory Manual and Workbook

By

SCOTT I. FAIRGRIEVE, PH.D. Anthropology Program and Department ofBiology Laurentian University Sudbury, Ontario, Canada and

TRACY S. OOST, H.B.A., H.B.Sc., M.Sc.(Cand.) Department ofBiology Laurentian Oniversity Sudbury, Ontario, Canada

Charles CThomas PUB LIS HER

•

LTD.

SPRINGFIELD • ILLINOIS • U.S.A.

Published and Distributed Throughout the World by CHARLES C THOMAS • PUBLISHER, LTD. 2600 South First Street Springfield, Illinois 62704

This book is protected by copyright. No part of it may be reproduced in any manner without written permission from the publisher.

©2001 by CHARLES C THOMAS • PUBLISHER, LTD. ISBN 0-398-07202-7 Library of Congress Catalog Card Number: 2001130439

With THOMAS BOOKS careful attention is given to all details of manufacturing and design. It is the Publisher s desire to present books that are satisfactory as to their physical qualities and artistic possibilities and appropriate for their particular use. THOMAS BOOKS will be true to those laws of quality that assure a good name andgood will.

Printed in the UnitedStates of America R-3-CAMR

TO the students ofHuman Skeletal Biology at Laurentian University who provided us with valuable feedback.

PREFACE TO THE INSTRUcrOR

T he Human Skeletal Anatomy: Laboratory Manual and Workbook has been designed to help students who are enrolled in courses dedicated to this topic. It is the product of many years of designing and instructing a Human Skeletal Biology course for undergraduate students. The key to this manual is flexibility. Instructors may utilize as much or as little of the manual as they see fit. This manual is largely based on the regional approach to anatomy. However, the first section of the manual begins with a survey of the microscopic and macroscopic structure of bone. After grounding the student in the basics of bone structure the manual then turns to the gross morphological anatomy of skeletal elements. The axial skeleton is dealt with first, then the appendicular skeleton. However, as you will note, the manual is designed to cover material in an incremental fashion. Specifically, the anatomy of less complicated bones such as the ribs, sternum and hyoid are discussed prior to other axial bones in order to acquaint students with how to handle real bone material in the laboratory. Each successive laboratory session demands more from the student in both the level of understanding and expectations in assigned laboratory exercises. Each laboratory begins with an introduction in order to familiarize the student with the areas to be studied. Subsequently, the laboratory has a stated purpose with clear instructions of expectations and learning objectives. "Important Terms" are clearly indicated in boxes to stress to students that these must be understood. This is then followed by a clear laboratory Procedure for the student to follow. This usually involves the identification of particular features or assigning specific tasks as identified in the various Exercises. Finally, as a means of stressing the applicability of what has been learned in the laboratory exercise, the student will be requested to generate an evaluation of some aspect of the anatomy (such as using a method for determining age at death) from assigned specimens. The student is then required to interpret this information and produce, for the next class or session, a "Laboratory Research Report". Guidelines for these reports are contained within this manual. Diagrams/photographs have been provided for the students to label. These diagrams are meant to be a study guide. Instructors may wish to add vii

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Human Skeletal Anatomy Laboratory Manualand Workbook

anatomical features or deemphasize certain features accordingly. The Laboratory Assignments have been designed for a 2-3 hour laboratory session. Therefore, depending on the course, instructors may wish to use less of the manual than provided. However, the design of the manual is such that it does cover all significant anatomical features. Significance in this case pertains to that feature being useful in identification of fragmentary remains or in some form of analysis. We wish to make the point that no manual should be considered an exclusive tool for self-instruction. Anatomical study is very much a hands-on experience for the student, especially for those who aspire to pursue further studies in human skeletal analysis. This manual only covers the anatomy of the human skeleton. It is well known to instructors in this area that human skeletal biology also covers aspects of age-at-death determination, sex determination, stature, genetic ancestry, pathology, facial reproduction and skeletal anomalies for identification. This manual is meant to act as a basic instruction aid for skeletal anatomy, the root of all these other areas. In a brief survey of courses dealing with the human skeleton, it was found that there were as many ways of dividing the topics listed above as there were courses. Therefore, it was decided that the best fit for all courses was to provide just the anatomy of the human skeleton, including dental tissues, nonmetric variation, and basic osteometries. These topics seem to be covered in all courses, and as such, this manual will provide you with a good fit to your course.

PREFACE TO THE STUDENT his laboratory manual has been developed with the help, advice and feedback from students taking courses in Human Skeletal Biology over a period of several years. In order to progress in any discipline you must first understand the basic terminology within that discipline. In other words, learn how to communicate with other researchers. This is especially true of human anatomy, and in this case, human skeletal anatomy. As a result, this course of study is memory intensive. There are many terms and anatomical features that must be memorized. The laboratory exercises are designed to provide you with clear guidelines on what is expected of you in the lab. In most cases, you will be required to both read about skeletal anatomy from a text on the subject as well as to study relevant lecture notes. As a result you should go into your lab sessions well prepared to complete the lab exercises. This way of teaching a subject is structured to give you the theoretical background information first, and then to have it all reinforced with a practical lab session that is hands-on. You will notice that most of the terms in the lab manual are easily defined through use of your text, lecture notes, or other anatomy references. Although we have tried to use the most current anatomical terminology, you may encounter terms that are unfamiliar to you, or are not readily recognizable. This may be because another term for a particular bone or feature is being used rather than the familiar lecture/text term. An example of this may be the os coxa. Other names for this bone include the "innominate" (literally meaning 'no name'), and the "hip bone." It is important for you, as students, to be aware that terminology does change over time. You must also be aware of the other names of bones as they will come up in various publications. Schwartz (1995) actually has a section concerned with "Bone Synonymy" that you may wish to use as a reference. Initially, each laboratory starts with a rationale for performing the exercise. Typically, the introduction highlights the various features of the lab you are about to do. After a brief statement of the purpose of the laboratory exercise, we have provided you with a few statements of what you can do Before You Begin the lab. This serves as a reminder of what you should be doing before you come into the lab. Otherwise, you may find your knowledge-base

T

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Human Skeletal Anatomy Laboratory Manual and Workbook

is behind the other students and the lab exercises may be much more challenging than you anticipated. The Objectives listed provides you with a concrete list of what you are expected to be able to accomplish by the end of the lab session. You should think of this as a list of the types of questions you could be asked in a laboratory test situation. The Materials section is essentially a list of the equipment/specimens you will need in order to complete the lab exercise. If some of these are not available, your lab instructor will have made alternate arrangements. Important Terms will be listed inside a double-bordered box. These are the terms you must clearly understand by the end of the laboratory session. In many cases these terms are anatomical features of bones that you will be expected to learn for identification purposes. The Procedure is an actual outline of what you are to consider or do during your lab session. Within each section of the "Procedure" are exercises that require you to label a diagram or perform some other task. At the end of each lab is a section referred to as the Laboratory Research Report. This section of the lab exercise requires you to apply your new knowledge in a practical application. Usually you are required to generate data of some sort, such as applying an aging method to the bones you have studied and then to prepare a formal research report for submission and marking. This not only demonstrates how knowledge of a particular part of the anatomy can be applied in a practical way, but also requires you to examine the professionalliterature and discuss your results in that context. Not all instructors will require this portion of the lab be done, however, it does provide you with an excellent opportunity to review the literature on these topics and also see how the anatomical terminology is applied in real-life situations. The key to the successful use of this manual is preparation. The manual is purposefully designed to be a supplement to your course in human skeletal anatomy, not a substitution for the assigned text and lecture. If you approach the manual in that way, and use the other required sources in your course, you will find that the manual will help reinforce your understanding of human skeletal anatomy.

RESEARCH REPORT PREPARATIONt Upper level students are required to write scientific reports and term papers that are much more formal and involved than the laboratory reports written on a week-to-week basis in first year courses. A properly written scientific report is rather like a gift. A great deal of thought should go into choosing and presenting the contents, and this should then be packaged as painstakingly as possible. The best of gifts loses some of Reproduced with the kind permission of Dr. Gerard M. Courtin, Department of Biology, Laurentian University.

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Preface to the Student

xi

its impact if it is poorly wrapped with bits of ribbon and paper sticking out allover the place. A scientific report or paper is normally divided into the sections described below, although variations from this theme may be necessary at times to cope with the particularities of a certain type of research. You should consult your instructor about any deviations from this scheme.

1. Introduction This section should typically be done last. At this time the material in the report is fresh in your mind and you can write an Introduction that is clear, brief and to-the-point. The Introduction must cover the following points: a) Why the work is being done? b) A brief survey of the literature that leads up to the present work. c) A statement of what the report or paper to follow sets out to show (or prove).

2. Methods This section is indispensable as it allows the reader to appreciate whether or not your particular way of conducting your experiments is sound and likely to lead to valid data. It also permits another researcher to use your methodology and, either to duplicate your work to ensure himself/herself of its validity, or to perform similar work elsewhere or under different conditions for purposes of comparison. The criterion of a well-written Methods section is that someone who is totally unfamiliar with your work should be able to reproduce exactly what you have done. If the method is new, the description should read like a recipe in a cookbook. Only in the case of methods that are well established in the literature may one simply refer to the appropriate paper. For example, sex determination from the os pubis using the method by Phenice has been cited in the literature hundreds of times. One would simply state; "Sex was determined using the Phenice Method (1969)." Lastly, if one uses a method described in the literature but one modifies it in some way, then the modification must be described in detail.

3. Results It is a common misconception among many students that a Results section is comprised simply of data that are displayed either as graphs or as tables or as both. Although true to a point, there is far more to a Results section than that. First, there is a format for the presentation of Figures (graphs) and Tables that is more or less standard throughout the scientific literature. The best way to find examples is to study one of the current journals in the

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Human Skeletal Anatomy Laboratory Manual and WOrkbook

field that most interests you (e.g., American journal of Physical Anthropology, Internationaljournal of Osteoarchaeology). Pay particular attention to the format. You will see that the format does not vary greatly from paper to paper. In a typewritten or word processed manuscript, however, the figure caption is traditionally placed on the page facing the figure, not beneath it. However, given the advances made in computer technology and scanning of figures and generating graphs, you may wish to put your caption with figure number beneath your figure. A table title or caption is placed above the table. Remember that a figure should be kept simple and should carry a clear message ("a picture is worth a thousand words"). It is often wise to graph the same data in several different ways until you find that one that you feel makes the point most clearly. Note that in the case of tables, a double line separates the caption from the body of the table and that data are not separated by vertical lines but by the way in which the column headings are underlined. Note also that captions for both figures and tables should be sufficiently explicit to stand on their own without reference to the text, i.e., you should be able to look at a figure or table in isolation from the paper in which it appears and understand what it is about. So much for the visual presentation of data. This is only part of the Results. The other part is the verbal description; the text that describes the results and helps the reader to identify the main point that the writer is trying to make with the help of a given figure or table. Once again, pay attention to the way in which results are presented in a journal paper and the way in which the pertinent figure or table is referred to in the text. In a typed manuscript, a particular figure or table always follows the page or text in which it first appears.

4. Discussion This section is the "meat" of a report or paper. Here you attempt to do two things: a) to explain to the reader the value of your data, and b) to present the data in the context of other, similar findings in the literature, to show how your data agree (or disagree) with the data obtained by others. It is here that one displays one's ability to think, to analyse, to criticize, to infer, and even to predict. It is one thing to design an experiment properly and to gather the data with care and precision; it is quite another to extract the full meaning from those data. Often, data does not conform to your hypothesis. It is up to you to convince the reader that your data are believable or to point out possible errors or weaknesses. It is by demonstrating insight, honesty, and the fact that you are human that you establish your reputation as a good scientist. Lastly, do not for a moment think that the exercise is easy. Writing a discussion section is very hard work.

Preface to the Student

xiii

5. Conclusion This section should be brief and concise. Its aim is to highlight the major points of the report or paper. A reader should be able to gather the gist of your work simply by reading the Introduction and Conclusions.

6. Literature Cited This section is simply an alphabetical listing of all the authors that you have cited in your report. A complete citation should include the name)(s) of the author(s), the year, the title of the book, chapter from an edited book, or journal paper, the title of the journal, the volume and appropriate page numbers. Once again, your best guide to the format is to refer to a paper in a scientific journal (e.g., the AmericanJournal of Physical Anthropology). Remember that any work from which you draw ideas or information must be cited in the text. Failure to give credit to the work of others is considered plagiarism. This is "literary theft" and is regarded in the same light as any other kind of theft. When cited in the text, the work must also be listed in the Literature Cited section. Pay particular attention to how journal articles and books are cited. Although there is some variation between journals, a consistent format is always followed. Your instructor will likely indicate which type is preferred.

CONTENTS Page About theAuthors .............................................ii Preface to the Instructor vii Preface to the Student . . . . . . . . . . . .ix Research Report Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .x Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xv List ofFigures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xvii List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxi Chapter 1. HISTOLOGY AND MORPHOLOGY OF BONE 2. RIBS, STERNUM AND HyOID 3. VERTEBRAL COLUMN 4. UPPER LIMB 5. LOWER LIMB 6. THE SKULL 7. DENTITION 8. NONMETRIC VARIATION 9. OSTEOMETRICS

3 17 25 38 55 77 104 121 138

Answer Key References

155 165

xv

FIGURES Page Figure 1.1.

Figure 1.2. Figure 1.3. Figure 1.4. Figure 1.5. Figure 1.6. Figure 2.1. Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure

2.2. 2.3. 2.4. 2.5. 2.6. 2.7. 3.1. 3.2. 3.3. 3.4. 3.5. 3.6. 3.7.

Figure 4.1. Figure 4.2. Figure 4.3.

Detailed photograph of trabecular or "spongy" bone as seen in a distal tibia from a bovid. Note the compact bone, medullary cavity, fused epiphysis with the vestiges of an epiphyseal growth plate. . Histological section of the midshaft of a femur, specimen A. . Histological section of the midshaft of a femur, specimen B Histological section of the midshaft of a femur, specimen C. . Histological section of the midshaft of a femur, specimen D. Histological section of the midshaft of a femur, specimen E Anterior view of the manubrium, body of sternum, and xiphoid process. . Posterior view of an adult human rib. . Anterior view of an adult hyoid bone. . Costal facet of rib 1. . Costal facet of rib 2. . Costal facet of rib 3. . Costal facet of rib 4. . Left lateral view of a tenth thoracic vertebra (T10). . Superior view of a first cervical (atlas) vertebra. . Anterior view of a second cervical vertebra (axis) Left lateral view of a third lumbar vertebra (L3). . Anterior aspect of a typical adult sacrum. . Posterior aspect of a typical adult sacrum. . Posterior aspect of two sacra for the assessment of spina bifida occulta. . Inferior view of a left clavicle Posterior view of a right scapula. . Anterior view of a right scapula. . xvii

12 14 14 15 .15 16 20 21 22 24 24 24 24 30 31 32 34 35 36 37 43 44 45

Human Skeletal Anatomy Laboratory Manualand Workbook

xviii

Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure

4.4. 4.5. 4.6. 4.7. 4.8. 4.9. 4.10. 4.11. 4.12. 4.13. 5.1. 5.2. 5.3. 5.4. 5.5. 5.6. 5.7. 5.8. 5.9. 5.10. 5.11. 5.12. 5.13. 5.14. 5.15. 5.16. 5.17. 5.18. 6.1.

Figure 6.2.

Figure 6.3. Figure 6.4. Figure 6.5. Figure 6.6. Figure 6.7. Figure 6.8. Figure 6.9.

Anterior view of a proximal left humerus. . 46 Anterior view of a distal I eft humerus. . 47 Posterior view of a distal left humerus. . 48 Anterior view of the proximal end of a left radius. . 49 Anterior view of the distal end of a left radius. . 50 Posterior view of the distal end of a left radius 50 Anterior view of a proximal left ulna. . 51 Anterior view of a distal left ulna. . 52 Dorsal view of the bones of an articulated right hand. . 53 Palmar view of the bones of an articulated right hand. . 54 Lateral view of a right os coxa (innominate/hipbone). . 61 Medial view of a right os coxa 63 Anterior proximal right femur. . 65 Medial view of a proximal right femur. . 66 Posterior proximal right femur. . 67 Anterior distal right femur. . 68 Posterior distal right femur 68 Anterior of a right patella. . 69 Posterior of a right patella. . 69 Anterior view of a proximal right tibia 70 Posterior view of a proximal right tibia. . 71 Posterior view of a distal right tibia. . 72 Medial view of a proximal right fibula. . 73 Lateral view of a proximal right fibula. . 73 Medial view of a distal right fibula 74 Lateral view of a distal right fibula 74 Dorsal view of an articulated left foot. 75 Plantar view of an articulated left foot. 76 Left auditory meatus with auditory ossicles in articulation. . 85 Right lateral view (N orma Lateralis) of a skull. Note the spring holding the mandible in articulation and the clip holding the vault of the skull in place. . 88 Anterior view (Norma Frontalis) of a skull with a horizontal cut. 90 Inferior view (Norma Basalis) of a cranium. Note that the mandible is missing. . 92 Posterior view (Norma Posterioris) of a cranium. Note that the mandible has been removed. . 94 Superior view (Norma Superioris) of a skull. Note that the anterior of the skull faces the top of the photograph. . 95 Inferior aspect of the endocranium. . 96 Superior aspect of the endocranium. . 98 Superior view of a sphenoid 100

Figures

A posterior-anterior radiograph of an archaeological human cranium (mandible removed) from the Pasamayo Peruvian Collection housed in the Department of Biological Anthropology, University of Cambridge. . Figure 6.11. A posterior-anterior radiograph of an archaeological human cranium (mandible removed) from the Pasamayo Peruvian Collection housed in the Department of Biological Anthropology, University of Cambridge. . Figure 6.12. A posterior-anterior radiograph of an archaeological human cranium (mandible removed) from the Pasamayo Peruvian Collection housed in the Department of Biological Anthropology, University of Cambridge. . Occlusal view of permanent maxillary dentition demonFigure 7.1. strating the dental formula of 2-1-2-3 for the upper left quadrant of the mouth. . The mixed dentition of a 7-year-old. There are several Figure 7.2. adult teeth in the process of erupting in addition to the presence of various deciduous teeth. .... . . . . . . . . . Occlusal view of the permanent mandibular dentition Figure 7.3. showing the anatomical terminology of the various dental surfaces. Figure 7.4. A radiograph of a nonsupernumerary hetertopic upper right canine rotated so that the occlusal surface is oriented in the position normally occupied by the root (see arrow). The result is that the tooth was erupting out of the right maxilla adjacent to the right nasal margin Distal view of an upper premolar with a large carious Figure 7.5. lesion. Note the amalgam filling directly over the caries. . Figure 7.6. Mandibular dentition demonstrating many carious lesions and postmortem tooth loss. Note that the thir molars were either lost antemortem or are congenitally absent. Edentulous maxillae demonstrating total alveolar Figure 7.7. resorption. Note that one tooth was retained in life as evidenced by the tooth root sockets in the upper left of this individual's alveolus Longitudinal section of an upper premolar Figure 7.8. Occlusal view of permanent mandibular molars. . Figure 7.9. Figure 7.10. Lateral radiograph of dentions (A and B) for develop-

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Figure 6.10.

101

102

103

111

.111

.112

113

114

115

116 118 119

xx

Figure 8.1. Figure 8.2. Figure 8.3. Figure 8.4. Figure 8.5. Figure 9.1. Figure 9.2. Figure 9.3. Figure 9.4.

Human Skeletal Anatomy Laboratory Manual and Workbook

mental assessment of indicated teeth in crypts. Note that in radiograph A there is a supernumerary tooth erupting through the incisive foramen. . 120 Right and left aspects of the skull demonstrating traits 1,3,5,6,8, 11, 14, 17, 19,20,23,24,25,26, and 27. . ... 129 Frontalis view of the cranium demonstrating traits 2, 14, 17, 18, 19, and 21. . 130 Posterior and superior aspects of cranium demonstrating traits 5, 15, 17, 22, 23, 24, 25, and 26 131 Inferior aspect of the cranium demonstrating traits 3, 4, 6, 7,8,9, 10, 11, and 16 132 Superior view of the sphenoid demonstrating traits 12 and 13. . 133 Right lateral view of a skull demonstrating cranial landmarks (osteometric points) 145 Anterior view of a skull demonstrating cranial landmarks (osteometric points). . 146 Inferior (basal) view of a skull demonstrating cranial landmarks (osteometric points). . . . . . . . . . . . . . . . . . . . . .147 Right lateral view of a mandible demonstrating mandibular landmarks (osteometric points) 148

TABLES Page Table 1.1. Table 6.1.

Bone Markings Bones of the Skull

5 78

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HUMAN SKELETAL ANATOMY

Histology And Morphology Of Bone

HISTOLOGY AND MORPHOLOGY OF BONE INTRODUCTION H~stology,

.or microanatomy, is concerned with the rmnute structures of cells tissues ~d organs in relation to their function. As with all aspects of anatomy, an understanding ?f the nonn~l range of variation is necessary If one. WIshes. to ultimately interpret p~thOlOgIC?1 specIm~ns. In this exercise you WIll exannne the histology of hard tissue, namely, bone and dental tissues. Typically, the study of bone also includes the related connective tissues of cartilage and blood. In order to enhance your understanding of human. skeletal ~iology, it is important to appreciate the link between microscopic anatomy and gross (or macroscopic) morphology. Remember the axiom of anatomy, that "structure reflects function and function reflects structure". An appreciation of both the I!1acroscopi~ and microscopic anatomy are directly applicable to studies in both pathology and the aging process.

PURPOSE This lab will familiarize you with the basic properties of living bone, including structure function, growth, and development. '

BEFORE YOU BEGIN • •

•

Read the suggested chapter in your text book and relevant lecture notes. Unde~stand the objectives for this exercise. Familiarize yourself with the terms in the IMPORTANT TERMS list, for testing purposes.

OBJECTIVES At the end of this lab you will be able to: • Classi~y the bones of the human body according to the categories cited.

• •

• • •

3

Identify the general markings found on all bones. Microscopically identify cartilage, bone, and blood tissues and their significant features. Understand the functions of bone and related tissues. Identify the features of a growing long bone. Microscopically identify the features of a bone thin section.

MATERIALS •

• • •

prepared microslides: compact bone c.s. compact bone 1. s. cancellous bone hyaline cartilage developing endochondral bone developing intramembranous bone hematopoietic smear blood smear microscope disarticulated human skeleton articulated human skeleton

PROCEDURE A. Morphology of the Human Skeleton The human skeleton officially consists of 206 b0!1es that are divided into two categories, the axI.al skeleton, and the appendicular skeleton. ThIS number does not take into account extra sesamoid (bone formed within a tendon where it passes over a joint), wonnian or sutural accessory bones,' the numbers of which vary from one person to the next. The axial skeleton is composed of those bones that contribute to the central axis of the skeleton, such as the vertebrae and ribs. The appendicular skeleton is composed of the bones that form the limbs, or extremities. Namel~, .the bones of the arms and legs. In addition, the bones may be classified according to their overall shape. In this case there are four categories:

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Human Skeletal Anatomy

1. Short - bones that are as long as they are wide, e.g., calcaneus. 2. Long - bones of cylindrical shape, longer than they are wide, e.g., femur. 3. Flat - bones that are sheet-like in shape, arising due to the ossification of fibrous membranes, e.g., parietal. 4. Irregular - bones that have a complex shape that do not fit into one of the other categories, e.g., os coxa.

By now you will have noticed that the bones are not smooth. They have various features that are referred to as bone markings. These markings arise during the development of the bones to accommodate the formation of joints, sites of muscle attachment, and passing blood vessels and nerves. Bones, in fact, reflect the soft tissue around them. Knowing the general names of the different types of bone markings will help you to identify specific markings and bones to be learned later.

Exercise 1.3: Review the general types of bone markings in Table 1.1 Bone Markings, then identify these general markings on your provided bone specimens. B . Properties of Living Bone

Exercise 1.1: Using the provided disarticulated skeleton, familiarize yourself with the outlined bone categories by dividing the specimens into axial and appendicular groups. Next try to classify the bones listed in the provided exercise. Exercise 1.2: Place the name of each bone of the body in the appropriate space in the provided tables.

Bone is a living tissue of the human body, and is a type of connective tissue. As such, it has certain properties common to all connective tissues, as well as some properties specific to its classification as a hard tissue. The primary structural feature of all connective tissue is an overwhelming dominance of the matrix. This matrix varies somewhat, depending upon the type of connective tissue in question, but is always composed of extracellular material and organic proteins. The fibrous tissue that comprises tendons, as well as that in adipose (fat) tissue, is dominated by a protein matrix made up of collagen and/or elastin protein fibres. Cartilage and bone have a protein/ground substance matrix composed of protein fibres, nonfibrous proteins and inorganic substances. Hematopoietic tissue, or red bone marrow, which produces blood cells is a related connective tissue with a water-based fluid matrix. The distinguishing feature of bone is that it develops into a hard tissue due to the deposition of calcium and phosphate ions in the extracellular organic material. Specialized cells are needed to aid in this process, and they are known as osteoblasts ('osteo-' bone; '-blast' to make) and osteocytes ('-cyte' cell). Osteoblasts are cells that aid in the

Histology And Morphology Of Bone

5

Table 1.1 Bone Markings

formation of new bone as it develops from cartilage. Once the osteoblasts become surrounded by mineralized bone they are referred to as osteocytes, which aid in the

"remodeling" or replacement of existing bone. In this process, existing bone is resorbed by osteoclasts ('-clast' to break).

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Human Skeletal Anatomy

Exercise 1.4: Examine prepared slides of hyaline cartilage, developing endochondral bone, developing intramembranous bone, hematopoietic smear, and blood smear. Draw labeled diagrams of these slides in the spaces provided.

C . Functions of Bone Bone and its related connective tissues function in a number of different ways in the human skeleton. 1. Support - The compact portion of the bones provides a solid framework on which the muscles and other tissues attach. Cancellous bone supports the hematopoietic bone marrow. Cartilage provides support as well, but in a flexible form, such as that found in the nasal septum, and the disks between the vertebrae. 2. Protection - By virtue of its hard and strong nature, compact bone provides protection for various internal organs. For example, bone partially or completely surrounds portions of the central nervous system. 3. Body Movement - The attachment of muscles, tendons, and ligaments to the bones creates a system of levers throughout the body, allowing us to flex and extend various moveable joints. 4. Hematopoiesis - This is the production of blood cells, which is accomplished by the red bone marrow, or myeloid tissue, and is supported by the trabeculae of cancellous bone. 5. Mineral Storage - Bone attains its hard nature through the deposition of minerals such as calcium and phosphate in its extracellular matrix. The bone then acts as a reservoir for these minerals.

D . Anatomy of a Growing Long Bone There are two ways in which a bone may develop from fetal tissue. The first is

intramembranous, meaning that the bone mineralizes within a sheet-like membrane. This is how the flat bones of the skull develop. We will focus on the development of endochondral bone, meaning bone that develops within a cartilage precursor. A long bone, such as the tibia, provides a good example.

Exercise 1.5: Identify the features of a developing bone listed below using the disarticulated bones provided and the detailed photograph of a sectioned long bone (Figure 1.1) to assist you with the identification of internal features. 1. Epiphysis - This is the end, or "head" of a long bone. It will be found at both the proximal and distal extremities of the diaphysis (shaft) of the bone. 2. Diaphysis - This is the long tube-like shaft of the bone. 3. Metaphysis - A zone of bone formed by endochondral ossification encompassing a portion of both the diaphysis and epiphysis. 4. Articular cartilage - This is the smooth hyaline cartilage that is found covering the ends of bones where they meet up with, or articulate, with other bones. 5. Epiphyseal growth plate (hyaline cartilage) - This is an area between the epiphysis and the diaphysis where the hyaline cartilage (proliferating cartilage) is arranged in columns. Growth hormones regulate the deposition of minerals in this area to produce new spicules of hard bone. 6. Trabeculae - The term trabeculae refers to the spicules of bone that are found in the cancellous bone tissue, and that support the red bone marrow. 7. Spongy bone tissue - Spongy bone is more technically referred to as cancellous bone. Despite its airy appearance, it is

7

Histology And Morphology Of Bone

very strong, and oriented along the major stress lines of the bones.

8.

Compact bone tissue - Compact bone is the dense connective tissue that forms the cortex of the bones.

9.

Medullary cavity - This is the

11. 12. 13. 14. 15.

blood vessels concentric lamellae nerve osteocyte in lacuna canaliculi

F . Histological Structures of Teeth hollow area found inside the diaphysis of long bones where yellow bone marrow accommodates fat storage (in adults). 10.

Blood vessel - Numerous blood vessels are found throughout bone. These vessels include veins, arteries, and capillaries. They are tube-like structures which carry blood, and therefore, oxygen, nutrients, carbon dioxide, and wastes, to and from this tissue.

E. Histological Structures of Bone Viewed microscopically, human bone has a very distinctive structure, and is thus easily recognizable.

Exercise 1.6:

Using your textbook as a guide, view the compact bone cross section and longitudinal section micro slides, as well as the cancellous bone microslide. Label and identify the following structures on the drawing you produced in Exercise 3 of this laboratory assignment. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

trabeculae of cancellous tissue inner lamellae central (Haversian) canal osteon outer lamellae periosteum periosteal perforating (Sharpey's) fibers endosteum perforating (Volkman's) canals central (Haversian) canals

Viewed microscopically, the human tooth also has a very distinctive structure, and should also be easily recognizable. In this particular laboratory assignment you will not be examining the tooth as all dental structures will be examined in greater detail in laboratory #8.

Exercise

1.7:

questions and definitions.

Answer the review provide the required

G. Laboratory Research Report Bone is a dynamic tissue that is constantly remodeling. This remodeling is demonstrated by the creation of new osteons. This means that older osteons have been cut into, or fragmented, by newer osteons. This results in whole and incomplete osteons that will be visible under magnification. Osteon counts, whole and fragmentary, have been the basis for generating regression formulae for the purpose of estimating age at death in skeletally mature individuals. In order to familiarize you with this process, this exercise requires that you count the number of whole osteons in a histological sample. This exercise may be completed using the photomicrographs below or designated microscopes in your laboratory. Prepare your laboratory report using the required format. In this particular case your report should cover (at the very least) the literature on factors affecting whole osteon counts and the application of such a count. Use the diagrams to practice taking whole osteon counts.

8

Human Skeletal Anatomy

Exercise 1.1 1. Sternum 2. Ulna 3. Metacarpals

4. Parietal 5. Scapula. 6. Talus

_ _ _

_ _ _

Exercise 1.2a

I

BONES OF THE AXIAL SKELETON (80 Total) BODY REGION

I

NAME OF BONE RIGHT

LEFT Skull (28 total)

1.

Cranium (8 total)

3 15..

2.

4. 6. 7. 8. Face (14 total)

1.

2. 3.

4.

5. 7. 9.

6. 8.

10.

Ear Ossicles (6 total)

11. 13.

12. 14.

1. 3. 5.

2. 4. 6.

Hyoid (1 total) .

1. 2. 3. 4. 5.

Spinal Column (26 total)

Sternum (1 total; 3 fused)

(7 total)

(12 total) (5 total) (1 total; 5 fused) (1 total; 4 fused) 1. 2. 3.

Ribs (24 total)

1.

12.

9

Histology And Morphology Of Bone

Exercise 1.2b BONES OF THE APPENDICULAR SKELETON (126 Total) BODY REGION

NAME OF BONE RIGHT

LEFf Upper Extremities (64 total) Shoulder Girdle (4 total)

1. 3.

2. 4.

Arms (6 total)

1. 3. 5.

2. 4. 6.

Hands (54 total)

(8 in each hand) (5 in each hand) (14 in each hand)

1. 2. 3.

Lower Extremities (62 total) Pelvic Girdle (2 total)

1.

2.

Legs (8 total)

1. 3. 5. 7.

2. 4. 6. 8.

Feet (52 total)

1. 2. 3.

(7 in each foot) (5 in each foot) (14 in each foot)

10

Human Skeletal Anatomy

Exercise 1.4

Compact Bone, c.s. Magnification:

Cancellous Bone, sec. Magnification: _

Compact Bone, l.s. _

Magnification:

Hyaline Cartilage, sec. Magnification: _

_

11

Histology And Morphology Of Bone

Developing Endochondral Bone, sec

Developing Intramembranous Bone,sec.

Magnification:

Magnification:

_

Hematopoietic Smear

Blood Smear

Magnification:

Magnification:

_

_

_

12

Human Skeletal Anatomy

Exercise 1.5

Figure 1.1: Detailed photograph of trabecular or "spongy" bone as seen in a distal tibia from a bovid. Note the compact bone, medullary cavity, fused epiphysis with the vestiges of an epiphyseal growth plate.

1.

_

2•

_

3.

_

4•

_

5.

_

13

Histology And Morphology Of Bone

Exercise 1.7 Multiple Choice (choose the best single response for each question) 1. The flat, smooth textured area of articulation found at the end of a long bone is called a(n): a) lamella b) articular facet c) periosteum d) Bowman's capsule e) amphiarthosis 2. The thin sheet of connective tissue found adhering to the inner cortex of bones is called: a) Sharpey's fibre b) periosteum c) endosteum d) osteocyte e) mesosternum 3. Which a) b) c) d) e)

of the following is/are function(s) of the skeletal system: production of lymph production of blood support b andc all of the above

4. Red bone marrow is supported by: a) trabeculae b) osteons c) blood vessels d) compact bone e) calcium 5. The purpose of Volkman's canals is to: a) allow lymph to drain from the bones b) allow osteoblasts to move in and out of the bone c) provide passage for blood vessels in the bone d) drain hematomas from the bone during surgical procedures e) provide a means to introduce medication directly to the marrow cavity

Definitions Define the following terms: 1. Sesamoid bone

_

2. Wormian bone

_

14

Human Skeletal Anatomy

RESEARCH REPORT #1

Figure 1.2: Histological section of the midshaft of a femur, specimen A. Whole Osteon Count =- - - - - - - - - -

Figure 1.3: Histological section of the midshaft of a femur, specimen B. Whole Osteon Count =----------

15

Histology And Morphology Of Bone

Figure 1.4: Histological section of the midshaft of a femur, specimen C. Whole Osteon Count =

_

Figure 1.5: Histological section of the midshaft of a femur, specimen D. Whole Osteon Count =

_

16

Human Skeletal Anatomy

Figure 1.6: Histological section of the midshaft of a femur, specimen E. Whole Osteon Count =

_

Ribs, Sternum and Hyoid

RIBS, STERNUM AND HYOID INTRODUCTION A major component of the axial skeleton is the thoracic cage. In its entirety it consists of thirty-seven bones, of which twelve are included as segments of the spinal column (covered in next lab). This lab will introduce you to the identification of the remaining elements, consisting of the sternum and ribs. Knowledge of the articulations of each bone in the thoracic cage, and the ability to side any rib will be learned. Be sure to pay attention to the articulations of the ribs to the thoracic vertebrae; these will help you later in identifying particular vertebrae. The importance of sternal rib ends in forensic age at death assessment will be discussed. The hyoid, located in the neck, does not articulate with any other bone, however, it is also part of the axial skeleton, and as such will be covered here. Note its position and morphology; it can be of great forensic importance particularly in cases of suspected strangulation.

PURPOSE This lab will teach you how to identify the ribs, sternum, and hyoid bone, as well as specific features of each. You will also learn how to side the ribs. In addition, you will be introduced to the assessment of age at death using sternal rib ends.

BEFORE YOU BEGIN • • •

Read the suggested chapter in your text book and relevant lecture notes. Understand the objectives for this exercise. Familiarize yourself with the terms and articulations in the IMPORTANT TERMS list, for testing purposes.

17

OBJECTIVES At the end of this lab you will be able to: • Identify any human rib as being either left or right. • Specifically identify the first, second, tenth, eleventh, and twelfth ribs. • Identify the major features of a typical human rib. • Identify the articulations for the first, seventh, tenth, and twelfth ribs. • Identify the elements of the sternum, and all of their articulations. • Identify the features of the hyoid.

MATERIALS • • • • •

disarticulated human skeleton articulated human skeleton human sternum complete set of human ribs human hyoid

PROCEDURE A. Sternum The sternum is the most anteriorly situated component of the thoracic cage. Long and flat, it provides protection for the underlying heart. In adults the sternum is composed of three segments which are fused together: 1. Manubrium - the wide, flat, somewhat "Y" shaped element located most superiorly. 2. Body (gladiolus) - the long middle (main) portion of the sternum. 3. Xiphoid process - the small pointed segment located inferiorly. The sternum receives the costal cartilages of the true ribs, along its lateral aspects. Rib I articulates with the lateral facets of the manubrium, while rib II articulates where the manubrium and body meet at the sternal angle. Since rib II articulates with both the manubrium and body, a demifacet is located on each. Ribs III to VII articulate with full facets on each side of the body.

18

Human Skeletal Anatomy

The clavicles also articulate with the manubrium superiorly at the clavicular notches. Located between the left and right clavicular notches you will find the suprasternal (jugular) notch.

Exercise 2.1:

Refering to the provided specimens and descriptions above, label Figure 2.1 in your lab report, and list the required articulations.

Ribs Twelve pairs of ribs contribute to the formation of a structure known as the thoracic cage. The first seven pairs are attached directly to the sternum via the costal cartilages, and are referred to as true (vertebrosternal) ribs. Ribs vm to X are attached indirectly to the sternum via superjacent costal cartilage. These are called vertebrochondral ribs. However, they have been collectively termed false ribs when included with ribs XI and XII. Finally, ribs XI and XII are referred to as either false, free, or floating ribs since they are not attached to the sternum at all, and only articulate posteriorly with the vertebrae. It is interesting to note that individuals of Japanese ancestry, often have a floating 10th rib. Generally speaking, all ribs are similar to one another, being composed of a head and a body/shaft. Rib VITI most clearly represents the typical rib, therefore it will be used as our model. The head is the somewhat rounded end that articulates posteriorly with the vertebral centrum (or body) at the articular facet(s). The number of articular facets found on the head depends upon whether the rib articulates with one vertebra or two. Ribs I, X, XI, and XII articulate with only one vertebra, and therefore have only one facet. All other ribs have two articular facets for articulation with two vertebrae. Between these two facets is the interarticular crest. Extending ventrally from the rib's head is the body, or shaft. The body is essentially flattened mediolaterally, except for the frrst rib, where it is flattened craniocaudally. The smooth, rounded edge of the body is the superior border, while the sharp edge is oriented inferiorly. You will notice that this sharp edge is caused by a concave depression running the length of the shaft that is known as the costal groove. At the sternal end of the body you will find a concave depression that is the articular facet for the costal cartilage

Ribs, Sternum and Hyoid

that connects each rib to the sternum. Naturally, this facet is absent on the floating ribs, XI and XII. Between the head and the body is a narrow area known as the neck. The junction between the neck and body is delimited by a tubercle. This tubercle has both a nonarticular, and a faceted articular part that articulates with the transverse process of the corresponding vertebra. Tubercles are usually not present on ribs XI and XII. At approximately the point of the tubercle you will notice that the rib begins to arc laterally. The point at which this curve begins is called the angle of the rib. Both the frrst and second ribs have a number of unique features that may be used for identification. On the superior surface of the frrst rib you will notice two shallow depressions with a vaguely triangular raised area between them. The posterior depression is known as the groove for the subclavian artery. The anterior depression is the groove for the subclavian vein. The raised area between the two grooves is called the scalene tubercle since it provides attachment for the anterior scalene muscle. The second rib has a roughened tuberosity approximately half way along its curve, on the outer superior margin, where the serratus anterior muscle attaches.

Exercise 2.2: Referring to the descriptions above, and the specimens provided by your instructor, label Figure 2.2 of the rib in your lab report.

C. Hyoid The hyoid is distinguished as being the only bone in the body that does not articulate with another bone. It is located in the neck, and

19

provides for the attachment of tongue muscles and laryngeal connective tissue. Its appearance is somewhat reminiscent of an edentulous mandible. The body is the main portion of the hyoid, and it has a slight curve anteriorly. Posteriorly it has two laterally oriented branches that curve upwards towards the skull. Each branch ends in a greater cornu. At the point where the branches begin to angle away from the body you will also notice smaller projections extending superiorly. These are the lesser cornu.

Exercise 2.3: Referring to the description above, carefully examine the hyoid specimens provided in your laboratory. Figure 2.3 has been provided for you to label.

D. Laboratory Research Report Yet another way of assessing age in the human skeleton of adults is by using the principle of surface metamorphosis. This refers to changes that occur to specific surfaces of bone as an individual ages. Unfortunately, this process is variable with the sex, age and even genetic heritage of the individual. In this research report we are introducing one of these methods that has been developed for the sternal end of the fourth rib. The authors of this method chose the fourth rib due to its accessibility during autopsy (Iscan, Loth, and Wright, 1984; Iscan and Loth, 1985; 1986; 1987). In this instance, using either the specimens provided by your instructor in the lab or the photographs provided in this manual, evaluate the sternal rib-end phase of the specimens indicated. Your laboratory report should cover the factors affecting the assessment of the phase. Please note that you are only requested to assess the phase and not to affix an age as this is dependent upon biographical information not provided to you (i.e., sex, and genetic heritage). Your instructor will provide you with the necessary references in order to perform your assessments.

20

Human Skeletal Anatomy

Exercise 2.1

1,

_

2,

_

3.

_

4 ,.

_

5,

_

6,

_

7.

_

Articulations List all of the bones that articulate with the following: a) Manubrium:

_

b) Sternal Body:

_

c) Xiphoid Process:

Figure

2.1: Anterior view of the manubrium, body of sternum, and xiphoid process.

_

21

Ribs, Sternum and Hyoid

Exercise 2.2

Figure 2.2: Posterior view of an adult human rib. 1.

-------------

4.

_

2.

_

5.

_

3.

_

6.

_

Articulations List all of the bones that articulate with the following: a) First Rib:

b) Seventh Rib:

c) Tenth Rib: d) Twelfth Rib:

22

Human Skeletal Anatomy

Exercise 2,3

Figure 2.3: Anterior view of an adult hyoid bone.

1.

_

2'

_

3

0,

_

23

Ribs, Sternum and Hyoid

Fill-in

(Complete each statement with the appropriate term) 1. The sternum is composed of 2. The

segments. is the joint between the manubrium and body.

3. Rib IX is an example of a 4. There is/are 5. The 6. The

rib. articular facet(s) on the head of rib I. of the hyoid provide attachment for the stylohoid ligaments.

ribs do not articulate with the sternum.

7. The most inferior portion of the sternum is called the

_

8. The

tubercle is only found on the first rib.

9. The

is the only bone that does not articulate with another bone.

10. The anterior.

rib may be identified by the presence of the tuberosity for the serratus

24

Human Skeletal Anatomy

RESEARCH REPORT #2

Figure 2.4: Costal facet of rib 1.

Phase:- - - - -

Figure 2.6: Costal facet of rib 3.

Phase:- - - - -

Figure 2.5: Costal facet of rib 2.

Phase:- - - - -

Figure 2.7: Costal facet of rib 4.

Phase:- - - - -

25

Vertebral Column

VERTEBRAL COLUMN INTRODUCTION A major structural feature of the axial skeleton is the vertebral column. It consists of ~6 bon~s arranged in an s-shaped, curved vertical aXIS. The vertebral column provides suppo~ for the body, as well as providing protection for the delicate spinal cord. The five functional categories of vertebrae are cervical, thoracic, lumbar, sacrum, and coccyx. While all vertebrae have a similar ge~eral structure, each category has certain unique features which aid in identification. The ~ertebral column is also highly susceptible to the effects of disease and aging, and these effects may be readily noted.

PURPOSE This lab will introduce you to the various features and categories of human vertebrae and how to identify them. You will als~ l~arn how to identify and assess the effects of disease on the vertebral column.

BEFORE YOU BEGIN • • •

Read the suggested chapter in your text book and relevant lecture notes. Unde~stand the objectives for this exercise, Familiarize yourself with the terms and articulations in the IMPORTANT TERMS list, for testing purposes.

OBJECTIVES At the end of this lab you will be able to: • Identify the bone markings of a typical vertebra. • Classify any vertebra as either cervical thora~ic, lumbar, sacrum, or coccyx. ' • Identify and make a basic assessment of one of the diseases affecting the vertebral column.

MATERIALS • • • •

articulated human skeleton disarticulated human skeleton articulated vertebral column individual, disarticulated human vertebrae

PROCEDURE A. General Vertebral Morphology All vertebrae can be classified as either true (movable) vertebrae, or false (fixed) vertebr~e. Within these two very broad categones, however, there are five functional categories. The first three functional categories are cervical, thoracic, and lumbar; the true vertebrae. The false vertebrae func~onally include the sacrum, and coccyx. De~pI~e apparent wide morphological vananon, all of these vertebrae have some general features in common with each other. 1. Body

(centrum) - The large, thick,

round~d

area that is oriented anteriorly when in anatomical position.

2. Vertebral arch - Posterior semicircle of bone created by lever-like processes extending from the body. 3 . Vertebral foramen - The opening delimited by the body and vertebral arch that allows passage of the spinal cord through the vertebrae. 4. ~e~icles - Short, thick dorsal projecnons from the body, contributing to the vertebral arch.

5. Vertebral notches (superior and !nfe~ior) - C~eated by the superior and mfenor concavity of the pedicles. 6. Intervertebral foramina - De-limited by the superior and inferior vertebral notches of adjacent articulated vertebrae.

26

Human Skeletal Anatomy

7. Laminae (sing. lamina) - Continuous with the pedicles, they extend dorsomedially to complete the vertebral arch.

8. Spinous process - Mid-dorsal projection completing the vertebral arch at the junction of the laminae. It often projects inferiorly as well.

9. Transverse processes - Lateral projections occurring at the junction between the pedicles and laminae.

10. Articular processes (superior and inferior) - Superior and inferior projections of bone occurring at the junction between the pedicles and laminae. 11. Superior and inferior articular facets - Smooth, oval areas located on the articular processes for articulation between vertebrae. 12. Epiphyseal ring - Annular area of smooth bone found around the circumference of the superior and inferior faces of the body. This bone is derived from the annular epiphysis.

Exercise 3.1:

Referring to the terms above, label the photograph of a typical vertebra (Figure 3.1) in your lab report.

B . Identification of Cervical Vertebrae The first seven vertebrae located below the skull are referred to as cervical vertebrae. Except for the first two cervical vertebrae, which have specialized functions, all of the cervical vertebrae have certain general features in common. The first cervical vertebra (C1) is known as the atlas because it supports the skull. The resulting atlanto-occipitaljoints accommodate nodding and lateral movements of the head. It is ring-like in structure, with both an anterior and posterior arch, encircling the central vertebral foramen. Similar to other

, Vertebral Column

27

(or transverse) ligament of the atlas which anchors the axis to the atlas. The axis also has superior and inferior articular facets for articulation with the other vertebrae, as well as transverse processes and foramina.

vertebrae, it also has laterally located transverse processes, although they are fairly small. Associated with the transverse processes are the transverse foramina. The poste~o: tubercle is located at approximately the midline of the posterior arch and replaces the spinous process prese~t on other vertebrae. The anterior tubercle is located on the outside of the anterior arch. In addition o~ the ~side s~ace of the anterior arch yo~ WIll notice an Indented, oval articular surface known as the facet or fovea for the dens (odontoid process) of the second cervical vertebra. Note that the atlas does not possess a vertebral body. Looking at the superior surface of the atlas you will notice two laterally located, concave articular surfaces. These are the superior articular facets and they articulate with the occipital condyl~s on the base of the skull. Immediately posterior to these facets are the indented right and left grooves for the vertebral arteries and first cervical nerves. Finally, medial to the superior articular facets are the tubercles for attachment of the transverse ligaments. The axis (Cz), a pivot for the rotation of the atlas and head, is the second cervical vertebra. Its most notable feature is the t?oth-like d.ens, or odontoid process, which nses supenorly to articulate with the first cervical vertebra. The dens actually develops from the remn~nts of the cartilaginous body of the first cervical vertebra when it separates and fuses to the body of the axis. Note that ~e ~ens has a head, and a slightly narrowed inferior !leck, or shaft. It also has a roughly oval artIcular facet on its anterior surface where it articulates with the fovea on th~ - inside of the anterior arch of the atlas. At the base of the posterior surface of the dens you will find a long narrow groove for the atlantl

Generally speaking, the cervical vertebrae are quite similar to each other. Each possesses a body (except for the atlas) with a vertebral arch surrounding a vertebral foramen. The inferior articular processes occur at the junctions between the laminae and the pedicles. Also in the general region of the pedicles, you will find the transverse processes, with their associated transverse foramina. Note that the cervical transverse processes are unique as they consist of two components. First, the bridge of bone enclosing the posterior aspect of the transverse foramen is known as the dorsal comI?onent. ~e strip of bone encircling the antenor aspect IS the ventral component. On th~ most lateral end of each component you WIll find the posterior and anterior tubercles respectively (only the anterior tubercle i~ present on C6, and on C7 there is no anterior tubercle present at all). The portion of bone that is anterior to the transverse foramen known as the costal element, may ~ separate, and thus, form a costal rib. Finally, except for C7, the cervical vertebrae have a divided, or bifid, spinous process. Exerci~e

3.2: Label the photographs of an atlas (FIgure 3.2) and axis (Figure 3.3) in your lab report. C . Identification of Thoracic Vertebrae The twelve thoracic vertebrae conform to the general morphology of most vertebrae, however, they do have some characteristics that distinguish them for identification purposes. First, all possess costal facets and/or demifacets for articulation with the ribs. Since TIO through TI2 articulate with only one rib on each side, they have only one roughly ovoid costal facet. The costal facet on T9 is particulary large and teardrop shaped. TI has a whole facet superiorly and

28

Human Skeletal Anatomy

a demifacet inferiorly; while each of 12 through T8 also articulate with two ribs, therefore they have two demifacets. These usually appear somewhat teardrop shaped, as if they are either dripping over the superior surface of the vertebral body, or they are being pushed up from the inferior surface. In addition, you will fmd that TI to TID have articular facets on their prominent transverse processes for articulation with the tubercle of the respective rib. The transverse processes of TIl and TI2 are shorter and stubbier, with those on TI2 resembling more closely the transverse processes of lumbar vertebrae. The spinous processes of the thoracic verterbrae are also very helpful for identification because they are very long and sharp, and generally pointed inferiorly. However, again note that TI2 often more closely resembles a lumbar vertebra, but may be distinguished by the presence of the articular facet for the rib.

Exercise 3.3: List the articulations and individualizing features of TI, T9, TIO, Til, and Tl2 in your lab report. D . Identification of Lumbar Vertebrae There are five lumbar vertebrae in the human body, and as with the thoracic vertebrae they generally conform to the typical morphology for all vertebrae. Initial identification as lumbar vertebrae is based on a lack of transverse foramina and lack of facets or demifacets for articulation with the ribs. They may be identified specifically as lumbar vertebrae by a few unique characteristics. The spinous process of a lumbar vertebra is short, and somewhat squared, rather than sharp and pointed as with the thoracic vertebrae. Also, the bodies of lumbar vertebrae are large and wide. Upon examination you will notice that the superior and inferior surfaces of LI to L4 are roughly parallel. The body of L5, however, is wedge-shaped. In contrast with the prominent transverse processes of the thoracic vertebrae, those on the lumbar vertebrae are shorter, and vaguely pointed. As with other vertebrae, the lumbar vertebrae

possess both superior and inferior articular processes for articulation with each other. Distinguishing the lumbar vertebrae, are mammillary processes located on the posterior margin of the superior articular processes. In addition, accessory processes are located at the root of each transverse process, just adjacent to the inferior vertebral notch.

Exercise 3.4: Label the photograph of a lumbar vertebra (Figure 3.4) in your lab report. E. Identification of the Sacrum The adult sacrum is normally composed of five vertebral segments that have fused together, however, some of the general features of vertebrae remain evident. You will notice that the sacrum has a concave anterior surface, and a convex posterior surface. Male and female sacra are somewhat different in overall shape, with the female's being shorter and broader to accommodate fetal development and childbirth. On the posterior surface of the sacrum you will notice a series of midsagittal (or median) projections that correspond with spinous processes. This series is known as the median sacral crest. If you view the sacrum from the superior aspect you will notice other typical features of the vertebrae. First is the large, wide vertebral body. If you locate the median sacral crest, you will also become aware that there are lamina enclosing an opening, known in this case as the sacral canal, rather than the vertebral foramen. Instead of transverse processes, the wing-like projections on either side of the body are referred to as alae (sing., ala). From this angle you will also notice the protruding superior articular processes, for articulation with L5. If there exists a thickened strip of bone in front of, and parallel to the articular surface, extending to the ala, it is known as the transverse process.

Exercise 3.5: Using the following list of features label the photographs that present the

, Vertebral Column

anterior (Figure 3.5) and posterior (Figure 3.6) views of a sacrum. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

auricular surfaces (sacroiliac joint) sacral promontory mammillary process lateral, intermediate, median sacral crests sacral horns sacral hiatus anterior and posterior foramen intervertebral foramen transverse line apex

F . Identification of the Coccyx Typically, the human coccyx is composed of four vertebral segments, though this number may range from three to five. Of these, only the first segment retains any general resemblance to other typical vertebrae. It has a definite body, however, the articular, transverse, and costal processes have coalesced to become the coccygeal cornua, or horns, that articulate with the apex of the sacrum. The segments that follow diminish in both size and discemable morphology.

G . Laboratory Research Report In Laboratory 1 we noted that the structure of

bone reflects the function of that bone. As a result, it should not be surprising that diseases and syndromes will also affect the structure of bone. The study of the effects of

29

diseases on tissues is known as pathology. Bone tissue will also demonstrate changes due to pathological processes. In this particular laboratory research report you are going to assess the posterior aspect of sacra for a condition known as spina bifida. This condition is a failure of the developing neural tube to close. There is a large literature base to support the fact that pregnant women who have low folic acid in the diet run the risk of having a child with a neural tube defect such as spina bifida. The standard means of assessing this condition is to record the most superior point reached by the sacral hiatus. You will see that in sacra without this condition, the sacral hiatus usually does not proceed to sacral segment number 4 (54). However, in spina bifida the sacral hiatus can be extended much further to include 53 and 52 (actually known as spina bifida occulta the non-clinical form). In a few instances, the entire sacral canal can be open. This would expose the nerves and render the person vulnerable to injury. For further information on this topic see Ortner and Putschar (1985). As your laboratory may not have many, if any, specimens demonstrating spina bifida or spina bifida occulta, we have provided photographs of two sacra (Figure 3.7) for you to evaluate. You are to record the extent of the most superior portion of the sacral hiatus in these specimens. Your discussion should cover the developmental aspects of spina bifida and the significance of finding this condition in human remains found in an archaeological context.

30

Human Skeletal Anatomy

Exercise 3.1

Figure 3.1: Left lateral view of a tenth thoracic vertebra (T10). 1.

6.

2.

7.

3.

8.

4.

9.

5.

10.

Vertebral Column

Exercise 3.2a

Figure 3.2: Superior view of a first cervical (atlas) vertebra.

1.

5.

2.

6.

3.

7.

4.

8.

31

32

Human Skeletal Anatomy

Exercise 3.2b

Figure 3.3: Anterior view of a second cervical vertebra (axis).

1.

3.

2.

4.

Vertebral Column

Exercise 3.3 List the identifying features and articulations of the following:

TI:

T9:

TIO:

TIl:

TI2:

33

34

Human Skeletal Anatomy

Exercise 3.4

Figure 3.4: Left lateral view of a third lumbar vertebra (L3).

1.

5.

2.

6.

3.

7.

4.

8.

_

Vertebral Column

Exercise 3.5a

Figure 3.5: Anterior aspect of a typical adult sacrum.

1.

4.

2.

5.

3.

6.

35

36

Human Skeletal Anatomy

Exercise 5b

Figure 3.6: Posterior aspect of a typical adult sacrum.

1.

6.

2.

7.

3.

8.

4.

9.

5.

10.

37

Vertebral Column

RESEARCH REPORT #3

Figure 3.7: Posterior aspect of two sacra for the assessment of spina bifida occulta.

Sacrum A Hiatus Level

Sacrum B

=- - - - -

Hiatus Level

=

_

38

Human Skeletal Anatomy

UPPER

PROCEDURE

LIMB

A. Identification of the Clavicle

INTRODUCTION The upper limbs consist of sixty-four bones (32 on each side). Included in this count are the bones of the hands, arms, and shoulder girdles. Recall that these bones are part of the appendicular skeleton. Each bone may be identified as a right or left on the basis of the bone markings of either the proximal or distal end. Radiographs of the clavicle and the proximal humerus can be useful in determining age at death in forensic cases.

The clavicle, commonly known as the collar bone, is a roughly S-shaped long bone that articulates with both the scapula and the sternum. The medial sternal end is basically ovoid in shape, while the lateral acromial end is considerably flattened. The superior and inferior surfaces of the shaft may be distinguished based on the bone markings present. Generally, the superior surface is relatively smooth, with some minor roughened areas for muscle attachment. On the inferior surface you will notice a shallow groove for attachment of the subclavius muscle.

PURPOSE This lab will introduce you to the bones and various features of the upper limb. You will learn how to side and identify isolated elements of the upper limb.

BEFORE YOU BEGIN • • •

Read the suggested chapter in your text book and relevant lecture notes. Understand the objectives for this exercise. Familiarize yourself with the terms and articulations in the IMPORTANT TERMS list, for testing purposes.

OBJECTIVES At the end of this lab you will be able to: • Identify the bones of the upper limb. • Side the bones of the upper limb.

MATERIALS • • •

articulated human skeleton disarticulated human skeleton disarticulated upper limb bones

Exercise 4.1: Using the general description above, and your text as a guide, identify the following features of the clavicle. Label the photograph (Figure 4.1) provided in your lab report. 1. 2. 3. 4. 5. 6. 7. 8. 9.

sternal facet sternal end shaft acromial end acromial facet costal tuberosity conoid tubercle nutrient foramen groove for subclavius muscle

B . Identification of the Scapula The shoulder girdle is comprised of both the clavicle and the scapula. The scapula is a flat, and somewhat irregular bone. It is roughly triangular in shape, with its most prominent feature being the spine that is oriented mediolaterally on its posterior surface. You will notice that the lateral end of the spine flares out into the acromion process.

39

Upper Limb

Projecting anteriorly from the lateral superior border is the coracoid process. Looking at the scapula from the lateral aspect you will see an oval depression, the glenoid fossa, for articulation with the humerus.

Exercise 4.2: Using the general description above, and your text as a guide, locate and identify the following features of the scapula. Label the photographs (Figures 4.2 and 4.3) provided in your lab report. 1. superior, medial (vertebral), and lateral (axial) borders 2. superior and inferior angles 3. subscapular, supraspinatous, and infraspinatous fossae 4. spine 5. acromion process 6. suprascapular notch 7. coracoid process 8. glenoid fossa 9. supraglenoid and infraglenoid tubercles 10. greater scapular notch 11. groove for subscapularis muscle 12. lateral lines (3) 13. groove for circumflex scapular vessels C . Identification of the Humerus

The humerus, or upper ann bone, is the largest bone of the upper limb. You will notice that, typical of many long bones, the humerus has a rounded proximal articular portion known as the head. Joining the head to the shaft is the neck, which is divided into two portions. The anatomical neck generally corresponds to the diagonal epiphyseal line joining the head to the shaft. The surgical neck, however, is the narrowed area just below the anatomical neck. The greater tubercle is the large bump located at the lateral

40

Human Skeletal Anatomy

aspect of the head, while the lesser tubercle is smaller and more anteriorly located. Between these two tubercles you will find a relatively deep groove known as the intertubercular sulcus. Looking at the distal end of the humerus, you will find two smooth projected areas for articulation with the lower ann bones. The lateral ball-like surface is called the capitulum, while the medial spool-shaped surface is the trochlea.

Exercise 4.3: Using the general description above, and your text as a guide, locate and identify the following features of the humerus. Label the photographs (Figures 4.4, 4.5, and 4.6) provided in your lab report. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

head anatomical neck surgical neck greater and lesser tubercles intertubercular groove (or sulcus) crests of the greater and lesser tubercles deltoid tuberosity medial and lateral epicondyles coronoid, radial, and olecranon fossae trochlea trochlear ridge capitulum lateral and medial supracondylar ridge spiral groove

D . Identification of the Radius The radius is the lateral of the two bones of the lower arm. It is notable for its concave, disk-like head that articulates with the capitulum of the humerus. At the distal end, the radius slightly flares mediolaterally, while flattening somewhat in the anteroposterior direction. On the lateral aspect of the distal

41

Upper Limb

end you will notice a pointed projection called the styloid process.

Exercise 4.5: Using the general description above, and your text as a guide, locate and identify the following features of the ulna. Label the photographs (Figures 4.10 and 4.11) provided in your lab report. 1. 2. 3. 4.

Exercise 4.4: Using the general description above, and your text as a guide, locate and identify the following features of the radius. Label the photographs (Figures 4.7, 4.8, and 4.9) provided in your lab report.

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

head articular circumference neck radial tuberosity anterior oblique line nutrient foramen interosseous border dorsal tubercle styloid process ulnar notch distal articular surface

5. 6. 7. 8.

olecranon and coronoid processes trochlear (semilunar) and radial notches tuberosity of ulna interosseous border supinator crest styloid process nutrient foramen head (radial or circumferential articulations)

F . Identification of Carpal Bones The wrist, or carpus, is composed of eight small bones known as carpals. Use the chart below, and your text to help you identify them. Recognition of right and left carpals, as well as intercarpal articulations, are not expected at this level of study.

E. Identification of the Ulna The ulna is the medial bone of the lower arm. It is easily identified by its proximal articular end which can generally be referred to as cup-shaped. This curved articular indentation is called the trochlear (semilunar) notch. On the lateral aspect of the proximal end you will notice a smaller articular indentation for the head of the radius. This marking is called the radial notch. Unique to the ulna, at the distal end of this bone is the head. Similar to the radius, the distal end of the ulna possesses a medially located styloid process. In this case the styloid process is narrow and pointed.

G . Identification of Metacarpal Bones The metacarpals are the long bones of the hand. In general, a metacarpal shaft is relatively short and curved longitudinally. It is also relatively round in cross section, with a cuboidal base that is broader dorsally. The head is round and broad. Metacarpals are numbered from one through five, beginning at the thumb side of the hand. Note that recognition of right and left metacarpals is not required at this level of study.

42

Human Skeletal Anatomy

H . Identification of Phalanges

I. Laboratory Research Report

The phalanges are the bones of the fingers. There are three phalanges in each finger, except in the case of the thumb (possessing two). These are referred to as proximal, middle, and distal (the middle phalanx is missing in the thumb). Phalanges are numbered according to the fmger they are from, starting with the thumb as number one. In general, the shaft of the hand phalanges is flattened on the palmar surface, resulting in a semicircular cross sectional outline. The five proximal phalanges have a single, oval, concave, proximal facet, and a trochlear head. The four middle phalanges have a trochlear head as well, but are distinguished by a double concavity in the proximal facet. The five distal phalanges also have a double concavity in the proximal facet, however, their distal ends are flattened rather than trochlear. As with the carpals and metacarpals, recognition of right and left phalanges is not necessary at this level of study.

The union of epiphyses to diaphyses is an important consideration in estimating the age at death of a subadult individual. It can be a very important system to use for age estimation as skeletons, especially in forensic contexts, are seldom complete. As such it is important for students to become aware of how to assess the degree of epiphyseal union. A common scheme for assessment has been suggested by Buikstra and Ubelaker (1994:41). In this system one merely makes a macroscopic assessment of the degree of union as follows:

Exercise 4.6: Using the general description above of the carpals, metacarpals and phalanges, and your text as a guide, locate and identify the following features of the hand. Label the photographs (Figures 4.12 and 4.13) provided in your lab report. 1. 2. 3. 4. 5. 6. 7. 8.

9. 10. 11. 12. 13. 14. 15.

trapezium trapezoid capitate hamate scaphoid lunate triquetra! pisiform frrst metacarpal bone (I) second metacarpal bone (II) third metacarpal bone (III) fourth metacarpal bone (IV) fifth metacarpal bone (V) proximal, middle and distal phalanges articulations: may be deduced from the above information.

•

unobservable = blank

•

open (epiphysis and diaphysis completely separate, no bony union) = 0

•

partial union (some union) = 1

•

complete union (all visible aspects of the epiphysis are united) = 2.

These scores are then compared to standards that have been established for each bone. Please note that your age estimation based on these data will provide you with an age range. One of the reasons for this is that you may not be in a position to determine the sex of the skeleton. As you know, females tend to mature physically earlier by up to two years when compared to males of the same group. As such, this will have an effect on your age estimate. For this research report, survey the literature on this aging technique using the humerus, clavicle and femur. Be sure to note the timing of the appearance of each epiphysis, the fusion times, and any sex differences. Be sure to discuss problems with using this technique. Please note that you will be expected to cite several references. Your instructor may also have specimens for you to assess in your laboratory session.

43

Upper Limb

Exercise 4.1

Figure 4.1: Inferior view of a left clavicle. 1.

5.

2.

6.

3.

7.

4.

8.

Articulations:

_

44

Human Skeletal Anatomy

Exercise 4.2a

Figure 4.2: Posterior view of a right scapula. 1.

6.

2.

7.

3.

8.

4.

9.

5.

10.

Articulations:

_

45

Upper Limb

Exercise 4.2b

Figure 4.3: Anterior view of a right scapula. 1.

4.

2.

5.

3.

6.

46

Human Skeletal Anatomy

Exercise 4.3a

1. 2.

3. 4.

5. 6. 7.

8.

Figure 4.4: Anterior view of a proximal left humerus.

47

Upper Limb

Exercise 4.3b

1.

2. 3. 4. 5.

6. 7.

8. 9.

Figure 4.5: humerus.

Anterior view of a distal left

48

Human Skeletal Anatomy

Exercise 4.3c

1.

2. 3. 4.

5. 6.

Humeral Articulations:

Figure 4.6: Posterior view of a distal left humerus.

_

49

Upper Limb

Exercise 4.4a

1.

2. 3. 4. 5.

6.

Figure 4.7: Anterior view of the proximal end of a left radius.

50

Human Skeletal Anatomy

Exercise 4,4b

1. 2. 3.

Figure 4,8: Anterior view of the distal end of a left radius. Exercise 4,4c 1. 2.

Radial Articulations:

Figure 4,9: Posterior view of the distal end of a left radius.

_

51

Upper Limb

Exercise 4.5a

1. 2. 3. 4. 5. 6. 7.

Figure 4.10: Anterior view of a proximal left ulna.

52

Human Skeletal Anatomy

Exercise 4.5b

1.

2.

3. 4.

Ulnar Articulations:

Figure 4.11: Anterior view of a distal left ulna.

_

53

Upper Limb

Exercise 4.6a

Figure 4.12: Dorsal view of the bones of an articulated right hand. 1.

6.

2.

7.

3.

8.

4.

9.

5.

10.

54

Human Skeletal Anatomy

Exercise 4.6b

Figure 4.13: Palmar view of the bones of an articulated right hand. 1.

4.

2.

5.

3.

6.

55

Lower Limb

LOWER LIMB

OBJECTIVES At the end of this lab you will be able to: •

INTRODUCTION The final appendicular division of the skeleton that you will study is the lower limb. The lower limbs consist of sixty-two bones (31 on each side). Included in this count are the bones of the pelvic girdle, legs, and feet. Each bone may be identified as a right or left on the basis of the bone markings of either the proximal or the distal end. The bones of the pelvic girdle (the os coxae) are particularly useful not only for sexing, but also for aging the individual. In addition, radiographic analysis of the proximal end of the femur may be used for aging, and assessment of osteoporosis.

PURPOSE This lab will introduce you to the bones and various features of the lower limb. You will learn how to side the lower limb bones, as well as being introduced to one of the more accurate methods of age determination using the pubic symphysis.

BEFORE YOU BEGIN • • •

Read the suggested chapter in your text book and relevant lecture notes. Understand the objectives for this exercise. Familiarize yourself with the terms and articulations in the IMPORTANT TERMS list, for testing purposes.

• •

Identify the bones of the lower limb, and their features. Side the bones of the lower limb. Provide a basic assessment of age at death by utilizing the pubic symphysis.

MATERIALS • • •

articulated human skeleton disarticulated human skeleton disarticulated lower limb bones

PROCEDURE A. Identification of the Os Coxa The pelvic girdle is composed of the left and right os coxae, which articulate posteriorly with the sacrum of the vertebral column. This joint between the os coxa and the sacrum occurs at the auricular surfaces, and is called the sacroiliac joint. Anteriorly, the two coxal bones articulate at the symphysis pubis (or pubic symphysis). Each coxal bone is formed by the fusion of three separate bones. The ilium is the bowl-like laterosuperior element. The ischium is the inferior, curved bone that supports the body's weight when in a sitting position. The pubis is the most anterior, and medially located of the three bones. These three bones fuse together in the acetabulum, the cup-like socket that is located inferolaterally, for articulation with the head of the femur.

56

Human Skeletal Anatomy

Exercise 5.1: Using the general description above, and your text as a guide, identify the following features of the os coxa. Label the photographs (Figures 5.1 and 5.2) provided in your lab report. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.

lunate surface of acetabulum greater and lesser sciatic notch iliac tuberosity iliac crest anterior superior iliac spine arcuate line anterior inferior iliac spine iliopubic eminence posterior superior iliac spine posterior inferior iliac spine preauricular sulcus ischial spine ischial tuberosity pubic tubercle superior and inferior pubic rami anterior, middle, and posterior gluteal lines 17. obturator foramen 18. pubic symphysis 19. auricular surface

B . Identification of the Femur The femur, or thigh bone, is the largest bone in the human body. As with the humerus, you will notice that it has a rounded proximal projection called the head. On the medial aspect of the head you will find an indentation known as the fovea capitis (or fovea capitis femoris) for attachment of the ligament that binds the femur to the acetabulum of the os coxa. The head narrows into a relatively short, broad neck, before attaching to the shaft (diaphysis). Proceeding down the posterior aspect of the shaft is a long, blunt ridge called the linea aspera. On the anterior aspect of the distal end of the femur you will see a smooth area for articulation with the patella, called the patellar surface. Additionally, the epicondyles project laterally and medially on either side of the patellar surface. If you look at the posterior aspect of the distal femur you will see that the epicondyles are roughened

57

Lower Limb

areas for muscle attachment on the lateral and medial condyles that articulate with the tibia.

Exercise 5.2: Using the general description above, and your text as a guide, identify the following features of the femur. Label the photographs (Figures 5.3, 5.4, 5.5, 5.6 and 5.7) provided in your lab report: 1. 2. 3. 4. 5. 6. 7. 8. 9.

greater and lesser trochanters trochanteric crest, line, and fossa spiral line gluteal tuberosity adductor tubercle supracondylar lines intercondylar fossa nutrient foramen groove for and origin of popliteus

C. Identification of the Patella The patella is the large sesamoid bone that develops in the quadriceps femoris tendon, and is situated most anteriorly in the knee joint. It has a broad base and an apex that points inferiorly in anatomical position. Note that the articular facet on the posterior aspect of the bone is asymmetrically divided into two. There is a smaller, steeply sloped medial facet, and a larger, gently sloped lateral facet. You will also notice that the superolateral margin of the patella has a slight notch that is the attachment site for the vastus lateralis tendon.

58

Human Skeletal Anatomy

Label the photographs (Figures 5.10, 5.11, 5.12) provided in your lab report: 1. 2. 3. 4. 5.

6. 7. 8. 9. Exer~i~e ~esc~ptIon

5.3: Using the general above, and your text as a guide, Identify the following features of the patella. Label the photographs (Figures 5.8 and 5.9) provided in your lab report: 1. 2. 3. 4.

base apex medial/lateral facets vastus lateralis tendon attachment

D . Identification of the Tibia The .tibia is the large bone of the lower leg that IS more commonly called the shin bone. Notice the arrangement of medial and lateral condyles, and the medial and lateral intercondylar eminences on the proximal aspe?t .of ~he bone. On the anterior aspect of th~ tibia, Just below the articular region you WIll .s~e a large .roughened projection called the tibial tuberosity. The distal end of tibia is nota~le for the large projection called the medial malleolus. Opposite to the medial malleolus, on the lateral side of the distal tibia, is the fibular notch.

E. Identification of the Fibula The fibula is the laterally positioned long bone of the lower leg. Its proximal end is m~ked by a. roughly triangular shaped head WIth ~ styloid process (or apex) that points superiorly. The opposite side of this proximal end is marked by the tibial facet, for articulation with the tibia. The distal portion of the fibula ends in the lateral malleolus with the articular facet for the talus occurring on the opposite side.

Exer~i~e ~esc~ptIon

5.5 : Using the general above, and your text as a guide, Identify the following features of the fibula. Label the photographs (Figures 5.13, 5.14, 5.15,5.16) provided in your lab report: 1. 2. 3. 4. 5. 6. 7.

Exer~i~e ~esc~ptIon

5.4: Using the general above, and your text as a guide, Identify the following features of the tibia.

posterior intercondylar area proximal fibular facet anterior border interosseous border nutrient foramen medial malleolus groove for tibialis tendon area of squatting facet solealline

head styloid process/apex lateral malleolus anterior border malleolar fossa articular facet for talus tibial facet

59

Lower Limb

F . Identification of the Tarsal Bones

G . Identification

of

the

Metatarsal

Bones There are seven tarsal bones in each ankle. The largest of these is the calcaneus (heel bone). The second largest is the talus, which articulates with both the tibia, and fibula. You will need to be able to side both the calcaneus, and the talus. There are several bone markings of both the calcaneus and talus that you are required to know, as well as articulations for all tarsals. Use the following list to guide you. 1. talus: a. head b. neck c. trochlear surface d. medial and lateral posterior tubercles e. medial and lateral articular surfaces f. articulations: fibula, calcaneus, tibia, and navicular. 2. calcaneus a. posterior surface (calcaneal tuberosity) b. sustentaculum tali c. groove for flexor hallicus longus d. anterior, medial, and posterior talar articular facets e. articulations: talus, cuboid 3. cuboid a. articulations: calcaneus, lateral cuneiform, metatarsal IV, metatarsal V, (occasionally articulates with the navicular) 4. navicular a. articulations: talus, medial cuneiform, intermediate cuneiform, lateral cuneiform, (occasionally articulates with the cuboid) 5 . medial cuneiform a. articulations: navicular, intermediate cuneiform, metatarsals I and II 6. intermediate cuneiform a. articulations: navicular, medial cuneiform, lateral cuneiform, metatarsal II 7. lateral cuneiform a. articulations: navicular, intermediate cuneiform, cuboid, metatarsals II, III, and IV.

The metatarsals are the long bones of the foot. In general the body is long and slender, with a wedge-shaped base, and a laterally compressed head. Metatarsals are numbered one through five, beginning at the large toe side of the foot. Note that recognition of right and left metatarsals is not required at this level of study.

H . Identification of the Phalanges The phalanges are the bones of the toes. There are two phalanges in the large toe, and three in each of the other toes. These are referred to as proximal, middle, and distaL Phalanges are numbered according to the toe that they are from, starting with the large toe as number one. In general, the shaft is round in cross section. The proximal phalanges have a single, concave proximal articular facet, and a distal trochlear head. Middle phalanges have a double concavity in the proximal facet, and a distal trochlear head. Finally, distal phalanges have a double concavity in the proximal facet, but are easily distinguished from middle phalanges due to the expanded and flattened terminal end. Note that recognition of left and right phalanges is not necessary at this level of study.

Exercise 5.6: Using the general description above, and your text as a guide, identify the features of the bones of the foot. Label the photographs (Figures 5.17 and 5.18) provided in your lab report. I. Laboratory Research Report The os coxa is one of the most important skeletal elements for assessing the age and sex of adult skeletal remains. In forensic contexts, this information will be the basis for providing an osteobiography, or profile, of the individual. This is one of the first steps to identifying these remains. In archaeological contexts, the age and sex are important when these aspects are being

60

Human Skeletal Anatomy

considered in light of pathology and nutrition. The evaluation of an os coxa for indicators of age and sex draw upon two factors; the first of these is that changes occur over time to several surfaces of the os coxa; the second depends upon certain areas of the bone exhibiting differences attributable to the individual's sex. The differing form of anatomical structures due to the sex of the individual is known as sexual dimorphism. Although both of these factors seem to indicate that evaluating the os coxa for age and sex is an easy practice, it is important to consider that there is going to be a range of variation that exists both within and between populations. As such, bony eminences that serve to indicate a distinguishing feature between the sexes in one group, may not be equally applicable in another. With respect to aging, the use of surface metamorphosis, as referred to in rib-end aging in Laboratory #2, is the basis for aging an adult os coxa. The same limitations noted in Laboratory #2 apply to these aging methods as welL In order to introduce you to aging and sexing of the os coxa, we have two potential laboratory research reports for your instructor to choose from below. The first of these is known as the Suchey-Brooks method for evaluating the pubic symphysis for age (Brooks and Suchey, 1990). This method requires the analyst to become familiar with a written description and models in order to assign one of six phases. Once this is accomplished, the phase is then compared to age standards of each phase which are dependent upon the sex and, if known, the genetic heritage of the individuaL Your instructor will cover this method in greater detail and provide you with

models or photographs and descriptions of each of the phases. However, it is usually standard practice to first provide an assessment of the sex of the os coxa. One of the easiest methods was published by Phenice (1969). This method requires the analyst to evaluate three different structures on the os pubis. The simplicity of the system is that you examine the os pubis for the presence or absence of these structures. Therefore, each of these structures is supposed to demonstrate an aspect of sexual dimorphism. As a result, you may have two out of the three or three out of three indicators for a certain sex. Your instructor will provide you with the standards for this method. Several texts, such as White and Folkens (2000) outline this method and studies of its accuracy. Therefore, the assignments based on these methods are as follows: Using the Suchey-Brooks method, evaluate the age phase of each of the provided pubic symphyses. Your discussion should cover studies utilizing this method. There should also be a consideration of the application of this method. or Using the Phenice method evaluate the sex of each of the provided os coxae. Provide your assessment for each of the three features used in this method. Your discussion should cover studies that have tested this method against others.

Lower Limb

Exercise 5.1a

Figure: 5.1: Lateral view of a right os coxa (innominate/hipbone).

61

62

Human Skeletal Anatomy

1.

2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

15. 16. 17.

Lower Limb

Exercise 5.1b

Figure 5.2: Medial view of a right os coxa.

63

Human Skeletal Anatomy

64

1. 2.

3. 4.

5. 6. 7.

8. 9. 10. 11.

Articulations: - - - - - - - - - - - - - -

65

Lower Limb

Exercise 5.2a

Figure 5.3: Anterior proximal right femur. 1.

4.

2.

5.

3.

6.

66

Human Skeletal Anatomy

Exercise 5.2b

Figure 5.4: Medial view of a proximal right femur. 1.

3.

2.

4.

Lower Limb

67

Exercise 5.2c

Figure 5.5: Posterior proximal right femur. 1.

4.

2.

5.

3.

6.

68

Human Skeletal Anatomy

Exercise 5.2d 1. 2. 3. 4.

Figure 5.6: Anterior distal right femur. Exercise 5.2e 1. 2. 3. 4. 5.

6.

Femoral Articulations:

Figure 5.': Posterior distal right femur.

_

69

Lower Limb

Exercise 5.3a

1. 2.

3.

Figure 5.8: Anterior of a right patella. Exercise 5.3b

1.

2. 3. 4.

Figure 5.9: Posterior of a right patella.

70

Human Skeletal Anatomy

Exercise 5.4a

1.

2.

3.

Figure 5.10: Anterior view of a proximal right tibia.

Lower Limb

71

Exercise 5.4b

1. 2.

3. 4.

5. 6. 7.

8.

Figure 5.11: Posterior view of a proximal right tibia.

72

Human Skeletal Anatomy

Exercise 5.4c

1.

2. 3. 4.

Tibial Articulations:

Figure 5.12: Posterior view of a distal right tibia.

_

Lower Limb

73

Exercise 5.5a

1. 2.

3.

Figure 5.13: Medial view of a proximal right fibula. Exercise 5.5b

1. 2. 3.

Figure 5.14: Lateral view of a proximal right fibula.

74

Human Skeletal Anatomy

Exercise 5.5c

1.

2.

Figure 5.15: Medial view of a distal right fibula. Exercise 5.5d

1.

Fibular Articulations:

Figure 5.16: Lateral view of a distal right fibula.

_

Lower Limb

75

Exercise 5.6a

1. 2. 3. 4. 5.

6. 7. 8. 9. 10. 11.

12. 13. 14.

15. 16. 17. 18.

Figure 5.17: Dorsal view of an articulated left foot.

76

Human Skeletal Anatomy

Exercise 5.6b 1. 2. 3. 4. 5. 6. 7. 8.

9. 10. 11. 12. 13. 14. 15. 16. 17. 18.

Figure 5.18: Plantar view of an articulated left foot.

77

The Skull

THE SKULL

• • •

•

identify calvarial bones and their features. identify and name the joints of the skull. . identify human facial bones and their features. identify human auditory ossicles.

INTRODUCTION This exercise is composed of two sections that will challenge you to learn the bones al1:d bone markings of the skull. The s~u~l IS comprised of 28 bones that may be dIVId~ into 3 categories. There are eight calvan~ elements fourteen facial bones, and SIX auditory ~ssicles. The first s~ction of this .lab will introduce the major functional categones, and visible bones, with an emphasis on the calvarial elements. The next section deals with the facial skeleton and auditory ossicles. The cranium is relatively fragile, and should be handled with care at all times. As a general rule, one should have two hands on the skull whenever it is picked up. Further, a pad should be protecting the skull from hard surfaces whenever possible (a bean bag or skull ring is ideal).

PURPOSE This lab will introduce you to the major functional categories of the skull bones~ with detailed study of the bones of the calvana and face.

BEFORE YOU BEGIN • •

•

Read the suggested chapter in your text book and relevant lecture notes. Understand the objectives for this exercise. Familiarize yourself with the terms and articulations in the IMPORTANT TERMS list, for testing purposes.

OBJECTIVES At the end of this lab you will be able to: . • distinguish between calvarial and facial bones of the skull.

MATERIALS • • •

articulated human.skull disarticulated human skull articulated human skull with horizontal cut

PROCEDURE A. Functional Areas of the Skull The skull is divided into three functional areas. The calvaria consists of eight bones that encase the brain, while the facial ske!~ton is composed of fourteen bone~. In ~dditIon, there are three auditory ossicles In each middle ear, for a total of six auditory bo~es. By studying the skull from yan~us anatomical views you will be able to Identify all of the bones: 1. Norma Verticalis Frontal Parietal Occipital 2. Norma Lateralis Frontal Parietal Temporal Occipital Sphenoid Nasal Lacrimal Zygomatic Maxilla Mandible 3. Norma Frontalis Frontal Nasal Maxillae Zygomatic

78

Human Skeletal Anatomy

Table 6.1 Bones of the Skull

3. Norma Frontalis continued Lacrimal Ethmoid Sphenoid Temporal Vomer Inferior Nasal Concha

4. Norma Posterioris Parietal Occipital Temporal Mandible

5. Norma Basalis (mandible removed) Palatine Bone Maxilla Zygomatic Temporal Occipital Vomer Sphenoid 6. Auditory Ossicles (not visible from exterior of skull) Malleus Incus Stapes 7. The Interior Fossae (not visible from exterior of skull) Anterior Cranial Fossa Middle Cranial Fossa Posterior Cranial Fossa Venous Drainage Impressions

Exercise 6.1:

Using Table 6.1, and your text as a guide, identify the bones of the skull provided and list the required articulations.

B . Identification of Calvarial Elements In this section you will study the eight bones that contribute to the calvaria of the skull. Identify each bone and its markings, keeping in mind each bone's functional and structural relationship with the bones around it.

Frontal Bone The frontal bone is a single bone that forms the anterior third of the braincase. It is separated from the parietal bones by the coronal suture, from the sphenoid by the sphenofrontal suture, and from the nasal bones by the frontonasal suture. In the area around the orbit, the frontal bone is separated from the maxilla by the frontomaxillary suture, from the lacrimal bone by the frontolacrimal suture, and from the zygomatic bone by the zygomaticofrontal suture. Use your text to help you identify the following markings on the frontal bone: 1. 2. 3. 4. 5. 6. 7. 8.

supraorbital margins superciliary arches (brow ridges) orbital plates supraorbital notch/foramen trochlear spur/foramen zygomatic process temporal line temporal ridge

79

The Skull

9. 10. 11. 12. 13.

region of temporal fossa frontal crest frontal eminence sulcus for sagittal sinus nasal spine

Parietal Bone The middle portion the calvaria is formed by the left and right parietal bones that are separated down the midline by the sagittal suture. The parietals also form the coronal suture where they meet the frontal bone, and the lambdoidal suture where they meet the occipital bone. The parietals are separated from the sphenoid by the sphenoparietal sutures, and from the temporal bone by the squamosal sutures. Although the mastoid process is part of the temporal bone, the section of suture separating it from the parietal is called the parietomastoid suture. Use your text to help you identify the following markings on the parietal bones: 1. 2. 3. 4.

temporal lines (superior and inferior) frontal angle parietal foramen granular foveolae (arachnoid granulations) 5 . parietal eminence 6. meningeal artery impressions (anterior and posterior divisions) 7. groove for sigmoid sinus and sagittal sinus

Occipital Bone The posterior portion of the calvaria is formed by the occipital bone. This bone curves inferiorly to the base of the skull. The occipital bone forms the lambdoid suture at the parietal bones. The junction between the occipital and the mastoid process is called the occipitomastoid suture. Also, the occipital meets the sphenoid at the occipitosphenoid synchondrosis. Use your text to help you identify the following bone markings of the occipital bone: 1. superior and inferior nuchal lines

80

Human Skeletal Anatomy

2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.

external occipital protuberance and crest internal occipital protuberance foramen magnum occipital condyles hypoglossal canal posterior condyloid canal condylar fossa jugular notch/jugular foramen jugular process superior and lateral angles groove for occipital sinus groove for transverse sinus groove for sigmoid sinus pharyngeal tubercle

Temporal Bone There are two temporal bones that enclose the sides of the calvaria. The temporal is also composed of a large bony projection, called the petrous portion, that extends inwards to form the inner ear region, and as such, houses the auditory ossicles. The temporal bone is separated from the parietal by the squamosal suture, from the sphenoid by the sphenotemporal, and from the occipital by the occipitomastoid. The forward projecting zygomatic process is separated from the zygomatic bone by the zygomaticotemporal suture. Use your text to help you identify the following bone markings of the temporal bones: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18.

mastoid process external acoustic meatus tubular (ecto) tympanic plate mandibular fossa zygomatic process squamous portion supramastoid crest stylomastoid foramen occipitomastoid crest mastoid (digastric) notch sigmoid sinus carotid foramen jugular fossa articular tubercle suprameatal crest postglenoid process vaginal process parietal notch

81

The Skull

19. styloid process 20. petrous portion 21. internal acoustic meatus

Sphenoid Bone The single sphenoid bone is easy to identify due to its butterfly-like shape. The sphenoid contributes to the anterior floor of the cranium, as well as the sides of the skull. The sphenoid is separated from the frontal bone by the sphenofrontal suture, and from the temporal bone by the sphenotemporal suture. Use your text to help you identify the following bone markings of the sphenoid: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.

greater and lesser wings anterior/middle/posterior/clinoid process optic foramen chiasmatic groove hypophyseal fossa (sella turcica) dorsum sellae and clivus tuberculum sellae foramen rotundum/ovale/spinosum medial and lateral pterygoid plates superior orbital fissure ethmoidal spine jugum carotid sulcus foramen lacerum hamulus pterygoid fossa orbital surface

Ethmoid Bone The ethmoid bone is a singular bone contributing to the calvaria of the skull. It forms the middle portion of the anterior cranial floor, as well as the roof of the nasal cavity. The ethmoid is separated from the frontal bone by the frontoethmoid suture, from the sphenoid bone by the sphenoethmoid suture, and from the maxilla by the ethmoidomaxillary suture. In addition, the junction between the ethmoid and the lacrimal bone is called the ethmoidolacrimal suture. Use your text to help you identify the following bone markings of the ethmoid bone:

1. 2. 3. 4. 5. 6.

cribriform plate perpendicular plate crista galli orbital plate alae superior and middle nasal conchae

Exercise 6.2: Using the provided descriptions, and your text as a guide, identify the calvarial bones and features on the photographs provided in your lab report. C. Calvaria Report

Laboratory

Research

As we saw in laboratory 5, the bones of the pelvic girdle can be utilized to assess the age and sex of the individual. The skull can also be utilized for the same purpose. The skull will of course, house the dentition, the most accurate means of aniving at an age estimate in juveniles and young adults. The skull can also provide a gross estimate of age at death using the closure, or fusion, of the sutures between the bones of the calvaria. The basis of this method rests on the fact that the sutures gradually disappear over time as the bones of the calvaria unite. This process is known as synostosis. The degree of closure of specific sections of certain sutures is then compared to a series of defined standards and an age estimate may be determined. These sutures can be assessed on the outer table (tabula externa) or on the inner table (tabula interna). The method has been demonstrated to have various degrees of claimed success.. The margins of error published in the literature can range up to ± 10 years (for a review see Masset, 1989). One of the most widely used systems was put forth by Meindl and Lovejoy (1985). This system defined a series of sites to be evaluated on the tabula extema. These sites have been grouped into two systems, the Vault System (sites 1-7) and the Lateral-Anterior System (sites 6-10). The definitions of these sites are as follows: 1. Midlambdoid. Midpoint of each half of the lambdoid suture.

82

Human Skeletal Anatomy

2. Lambda. Ectocranial point found at the intersection of the sagittal and lambdoidal sutures. 3. Obelion. Ectocranial point found at the middle of a line connecting the parietal foramina. 4. Anterior sagittal. Juncture of the anterior third and posterior two-thirds of the length of the sagittal suture. 5. Bregma. Ectocranial point found at the intersection of the coronal and sagittal sutures. 6. Midcoronal. Midpoint of each half of the coronal suture. 7. Pterion. Usually the point at which the parietosphenoid suture meets the frontal bone. 8. Sphenofrontal. Midpoint of the sphenofrontal suture. 9. Inferior sphenotemporal. Intersection of the sphenotemporal suture with a line connecting both articular tubercles of the temporomandibular joint. 10. Superior sphenotemporal. Point two centimeters below junction with the parietal.

Rather than examining a specific point at each of these sites, one evaluates a one-centimeter area around the site. The scores for the degree of closure are defmed as follows: Score

o.

Open; no evidence of ectocranial closure. 1. Minimal; ranging from a single bony bridge across the suture to about 50 percent synostosis. 2. Significant; a marked degree of closure but some portion remains incompletely fused. 3. Complete obliteration.

After scoring each of the sites, you simply add up the scores for the sites in one of the aforementioned systems. This sum is then compared to a standard to arrive at the age range of the skull based on the suture closure.

For your laboratory research report, assess the provided skull in your lab for ectocranial suture closure using the Meindl and Lovejoy (1985) system. If you have a complete skull, score all sites and devise composite scores for the "Vault System" (sites 1-7) and "Lateral-Anterior System" (sites 6-10). Do not assign an age estimate in this exercise. The purpose of this exercise is to acquaint you with evaluating the degree of synostosis. Your discussion should consider other methods of suture closure and sources of error in assessing closure.

D. Identification of Bones of the Face In this section you will study the fourteen bones that contribute to the face of the human skull. Identify each bone and its markings, keeping in mind each bone's functional and structural relationship with other bones.

Nasal Bone The left and right nasal bones are joined midsagittally at the nasal suture, forming the superior border of the nasal opening. They are joined to the frontal bone at the frontonasal sutures, and to the maxillae at the nasomaxillary sutures. Looking closely, you will notice that the external surface of the bone is slightly convex, with the internal surface being slightly concave. At the midline of the internal surface you will find the nasal sulcus, and the ethmoidal crest. Use your text to help you identify the following bone markings of the nasal bone: 1. nasal sulcus 2. ethmoidal crest

Maxillary Bone The left and right maxillary bones form the portion of the facial skeleton that extends from the eye orbits to the mouth, also contributing to the dental arch, and the borders of the nasal aperture. They join the frontal bone at the frontomaxillary sutures, the zygomatic bones at the zygomaticomaxillary sutures, and the palatine bones at

83

The Skull

the palatomaxillary sutures. They also articulate with each other at the intermaxillary suture. Use your text to help you identify the following bone markings of the maxillary bones: 1. 2. 3. 4. 5. 6. 7.

8. 9. 10. 11. 12.

infraorbital foramen and groove incisive foramen alveolar process maxillary sinus frontal process anterior nasal spine zygomatic process palatine process nasal aperture maxillary tuberosity anterior lacrimal crest inferior orbital rim

Lacrimal Bone The lacrimal bones are the smallest bones of the facial skeleton. The left and right lacrimal bones are found on the medial aspect of the corresponding eye orbit. They are located between the ethmoid (articulating at the ethmolacrimal suture) and the frontal process of the maxilla (articulating at the lacrimomaxillary suture). Use your text to help you identify the following bone markings of the lacrimal bones: 1. lacrimal sulcus

Zygomatic Bone The zygomatic bones fonn the upper portion of the left and right cheek area, extending from the inferior border of the eye orbits to the temporal bones. Each zygomatic bone (or zygoma) articulates with the frontal bone at the frontozygomatic suture, with the temporal bone at the temporozygomatic suture, and with the maxilla at the zygomaticomaxillary suture. Use your text to help you identify the following bone markings of the zygomatic bones: 1. 2. 3.

malar surface temporal process frontal process

84

Human Skeletal Anatomy

11. 12. 13. 14.

lingula mental protuberance digastric fossa mandibular notch

Vomer The vomer is a single bone that forms the lowest portion of the nasal septum. The vomer develops as left and right lamellae eventually fusing into one bone, however, lat~ral winc?s known as alae (singular: ala) are noticeable In the adult. The vomer articulates with the ethmoid, the maxillae, sphenoid and pala~ne bones. Use your text to help you identify the following bone markings of the vomer:

1. alae 2. perpendicular plate

Inferior Nasal Conchae 4. 5. 6. 7. 8.

maxillary process zygomaticofacial foramen zygomatico-orbital foramen orbital plate region of marginal tubercle

Mandible The mandible (lower jaw bone) is a roughly "U"-shaped bone when viewed from the occlusal and inferior aspects. It contributes to the lower portion of the dental arcade and articulates with the temporal bone at the temporomandibular joint (TMJ). Use your text t? help you identify the following bone markings of the mandible: 1. 2. 3. 4. 5. 6. 7.

body ascending ramus gonial angle alveolar process mental and mandibular fonnina coronoid process condylar neck 8. mandibular head (condyle) 9. mylohyoid groove and line 10. mental spines

The inferior nasal conchae (singular: concha) are located on the lateral walls of the nasal cavity. They are thin bones that CUNe medioinferiorly. All of the inferior nasal concha's articulations occur along its superior border, beginning with the maxilla. Next you will notice the thin articulations with th~ lacrimal via the lacrimal process, and the ethmoid.via the ethmoidal process. Finally, there IS another relatively substantial articulation with the palatine. Use your text to help you identify the inferior nasal conchae.

Palatine Bone T~e

l~ft

and right palatine bones join

rnidsagittally at the median palatine suture to

form the posterior third of the hard palate. These bones are roughly "L"-shaped in appearance, and also contribute to the formation of the nasal cavity. The palatine bones articulate with the maxillae at the palatomaxillary sutures, and via their maxillary processes. They also articulate with the middle nasal conchae via the ethmoidal crests. The orbital process of each palatine bone articulates with the maxilla sphenoid, and ethmoid. Use your text ~

The Skull

help you identify the following markings of the palatine bones:

bone

1. horizontal plate 2. perpendicular plate 3. orbital surface 4. sphenopalatine foramen

85

3. Stapes (Stirrup) - Also named for its shape, the stapes receives sound waves from the incus and transmits them to the inner ear. This occurs via the flat base portion of the bone which articulates with a passage to the inner ear known as the oval window.

Auditory Ossicles The auditory ossicles are the three small bones found in each of the left and right middle ears. They articulate with each other in the following order (laterally to medially): malleus, incus, stapes. Use your text to help you identify the following auditory ossicles:

Exercise 6.3: Using the provided descriptions, and your text as a guide, identify the facial bones and associated features on the photographs provided in your lab report. E. Face Laboratory Research Report

Figure 6.1:

Left auditory meatus with auditory ossicles in articulation.

1. Malleus (Hammer) - This club-shaped bone is attached to the tympanic membrane (in life) and vibrates when sound waves are passed to it from the ear drum. 2. Incus (Anvil) - Named for its shape, the incus articulates laterally with the malleus, and medially with the stapes. It vibrates when sound is passed to it from the malleus.

The skull contains a total of eight paranasal sinuses. These sinuses are essentially large air spaces within various bones of the face. Sinuses exist in the frontal, left and right maxillae, sphenoid and ethmoid bones. The clustering of these air spaces around the nasal cavity provides a means for air to circulate within each of the sinuses. The purpose of these air spaces is to lighten the weight of the bone without sacrificing strength. This is accomplished by the arch-like architecture of the sinuses. Sinuses, such as in the frontal bone, begin development during childhood and are generally completed in the late teens. However, there is going to be some variation in the timing. Once formed, the shape of the sinuses is fixed and may be visualized using radiographs. Forensically, this is important as it has been determined that the shape of frontal sinuses is unique to the individual and can therefore be used as a means of positive identification (Ubelaker, 1984). This technique may be used as a means of determining the positive identification of human skeletal remains in forensic contexts where no other means is possible. Using the radiographs printed in this manual, and a piece of acetate, trace the outline of the frontal sinuses

86

Human Skeletal Anatomy

present. Then overlay each of the sinus outlines as a basis of comparison. Report your findings and then discuss the timing of

the formation of frontal sinuses. governs this process?

What

87

The Skull

Exercise 6.1: List the articulations for the following bones: Frontal

Parietal

Occipital

Temporal

Sphenoid

Ethmoid

Nasal

Maxillary

Lacrimal

Zygomatic Mandible Vomer Inferior Nasal Concha Palatine

_

88

Human Skeletal Anatomy

Exercise 6.2/3a

Figure 6.2: Right lateral view (Norma Lateralis) of a skull. Note the spring holding the mandible in articulation and the clip holding the vault of the skull in place.

The Skull

Calvarial Elements and Features

89

Facial Elements and Features

1.

17.

2.

18.

3.

19.

4.

20.

5.

21.

6.

22.

7.

23.

8.

24.

9.

25.

10.

26.

11.

27.

12.

28.

13.

29.

14.

30.

15.

31.

16.

32.

90

Human Skeletal Anatomy

Exercise 6.2/3b

Figure 6.3: Anterior view (Norma Frontalis) of a skull with a horizontal cut.

The Skull

Calvarial Elements and Features

91

Facial Elements and Features

1.

11.

2.

12.

3.

13.

4.

14.

5.

15.

6.

16.

7.

17.

8.

18.

9.

19.

10.

20. 21. 22.

23.

92

Human Skeletal Anatomy

Exercise 6.2/3c

Figure 6.4: Inferior view (Norma Basalis) of a cranium. Note that the mandible is missing.

The Skull

Calvarial Elements and Features

93

Facial Elements and Features

1.

24.

2.

25.

3.

26.

4.

27.

5.

28.

6.

29.

7.

8. 9.

10. 11.

12. 13. 14. 15.

16. 17.

18. 19. 20. 21. 22. 23.

94

Human Skeletal Anatomy

Exercise 6.2d

Figure 6.5: Posterior view (Norma Posterioris) of a cranium. Note that the mandible has been removed. 1.

6.

2.

7.

3.

8.

4.

9.

5.

95

The Skull

Exercise 6.2e

Figure 6.6: Superior view (Norma Superiorisi of a skulL Note that the anterior of the skull faces the top of the photograph. 1.

4.

2.

5.

3.

6.

96

Human Skeletal Anatomy

Exercise 6.2f

Figure 6.7: Inferior aspect of the endocranium.

The Skull

Calvarial Elements and Features 1. 2.

3. 4. 5. 6.

7. 8. 9.

10. 11. 12.

13. 14.

15. 16. 17.

18.

19. 20. 21. 22.

23.

97

98

Human Skeletal Anatomy

Exercise 6.21:

Figure 6.8: Superior aspect of the endocranium.

The Skull

Calvarial Elements and Features 1. 2. 3. 4.

5. 6.

7. 8.

99

100

Human Skeletal Anatomy

Exercise 6.2h

Figure 6.9: Superior view of a sphenoid. 1.

7.

2.

8.

3.

9.

4.

10.

5.

11.

6.

12.

The Skull

101

RESEARCH REPORT #6

Figure 6.10: A posterior-anterior radiograph of an archaeological human cranium (mandible removed) from the Pasamayo Peruvian Collection housed in the Department of Biological Anthropology, University of Cambridge.

102

Human Skeletal Anatomy

Figure 6.11: A posterior-anterior radiograph of an archaeological human cranium (mandible removed) from the Pasamayo Peruvian Collection housed in the Department of Biological Anthropology, University of Cambridge.

The Skull

103

Figure 6.12: A posterior-anterior radiograph of an archaeological human cranium (mandible removed) from the Pasamayo Peruvian Collection housed in the Department of Biological Anthropology, University of Cambridge.

104

Human Skeletal Anatomy

•

DENTITION

• • • INTRODUCTION

articulated juvenile human skull with dentition individual teeth dental radiographs tooth and dental eruption models

PROCEDURE

Tee!h are rela~ively easy to identify when they are In a mandible or maxilla. However, loose ~eeth. p~esent special problems of Idenll~catlon. Tooth identification can play an Important role in both forensic ant!rr0pology and on archaeological sites. This lab concentrates on the identification and notation of dental variation.

PURPOSE This lab will introduce you to the various types of deciduous and permanent teeth with emphasis on identification, and variatio~. In addition, you will become familiar with microscopic identification of dental structures, and radiographic assessment of tooth development.

A. Identification of Adult Dentitions

• •

2:1:2:3 2:1:2:3

Read the suggested chapter in your text book and relevant lecture notes. Understand the objectives for this exercise. Familiarize yourself with the terms and articulations in the IM:PORTANT TERMS list, for testing purposes.

OBJECTIVES At the end of this lab you will be able to: • identify the teeth of both the deciduous and permanent dentition. • identify the macroscopic and microscopic features of a tooth. • provide a basic assessment of tooth development from a radiograph.

articulated dentition

In order from left to right the numbers indicate the number of incisors, canines, premolars, and molars.

The deciduous dental formula is:

2:1:2 or 2:1:0:2 2:1:2 2:1:0:2 You will notice that the first formula seems to indicate that no molars are present. However, the reality is that the deciduous molars actually occupy the positions that will be filled by the adult premolars. Therefore, the deciduous dentition does not include premolars.

Exercise 7.1:

MATERIALS •

adult

human

and

Humans develop both deciduous and permanent teeth over the course of their lifetime. Deciduous (baby) teeth are named as such because they are shed and replaced by the permanent teeth of the adult dentition. The deciduous dentition is comprised of 20 teeth, 5 in each of the upper and lower quadrants. The permanent dentition numbers 32, wit~ 8 in each quadrant. For purposes of companson a dental formula is used to describe the dentition. This formula denotes the type and number of teeth in one upper and lower quadrant of the mouth in the following way (see Figure 7.1):

BEFORE YOU BEGIN •

Deciduous

skull

with

Compare the teeth of an adult to those of a child. Annotate the differences in the table provided in your lab report.

105

Dentition

cutting; canines are used for tearing; premolars are used for tearing and cutting; and molars are used for grinding of food. Familiarize yourself with the following teeth and their respective positions in the dental arcade: a. Deciduous (Juvenile) tooth positions on the dental arcade: 1) central incisor 2) lateral incisor 3) canine 4) first molar 5) second molar b. Adult tooth positions on the dental arcade: 1) central incisor 2) lateral incisor 3) canine 4) first premolar 5) second premolar 6) first molar 7) second molar 8) third molar

B . The Dental Arcade and Anatomical Directions The term dental arcade describes the upper and lower arches of teeth in the mouth. Each type of tooth occupies a specific position in this arcade, and performs a specific function relative to its location. Incisors are used for

There are many ways of recording the presence of the teeth in a skeletal sample. Many organizations have developed a system of schematic diagrams and shorthand annotations to record the status of the teeth in th~ living and the dead. This is important as this can be used as a means of assessing the overall health of a population or, in forensic contexts, be key information at establishing a positive identification. Your instructor will be covering many of these systems and state a particular preference to you. All systems have advantages and disadvantages over each other. A common system used by physical anthropologists uses the first letter of the type of tooth. In permanent dentition this letter is capitalized and in deciduous dentition the letter is in lower case (often preceded by a lower case "d" to indicate a deciduous tooth). Therefore, adult and deciduous teeth would be denoted as follows:

106

Human Skeletal Anatomy

Then one has to be able to make the distinction between upper and lower teeth the side of the mouth, as well as which teeth of .a ~articular group are being represented. ThIS IS often done by affixing a sequential number to the letter already recorded. The number can also be placed next to the letter in ~uc~ a way that a superscript or subscript will Indicate an upper or lower position. Likewise, positioning this number to the left or the right of the letter will also serve to indicate that the tooth is from the left or right side of the mouth. For example, let us say that you have identified an isolated tooth as an upper right second molar. The notation in this system would be M 2 • Similarly, in th~ case of a deciduous lower left second incisor, the annotation would be 2di. Although this system covers all the identifying aspects of a tooth, it can be somewhat cumbersome. Recognizing this fact, odontologists have come up with a system that uses numbers for the teeth rather than letters. The teeth are numbered sequentially from 1 to 32, starting with the upper right third molar. If we consider the dental arcade as being similar to a clock, then we proceed clockwise until we end with tooth 32, the lower right third molar. The deciduous teeth are just a co~tinuation of this number system with 33 bemg the start at the deciduous upper right second molar and ending with tooth 52 the deciduous lower right second molar. The Federation Dentaire Intemationale (FDI) has a two digit system. First, the quadrant of the adult mouth is given a number: the upper right quadrant is number 1; the upper left 9.uadrant is number 2; the lower left quadrant IS number 3; and the lower right quadrant is number 4. In the case of deciduous teeth, the quadrants are numbered 5 through 8, using the same pattern. In addition to this, each of

the teeth is given a number, however, in this instance the numbering is sequential and starts with first incisor and proceeds to the thir~ molar. Therefore, there are only a maximum of 8 numbers for these teeth (with deciduous teeth the number proceeds from 1 to 5) (Taylor, 1978). As a result, an adult upper right second molar would be depicted as 17 because the quadrant number always pr~edes the tooth number. Similarly, a deciduous lower left second incisor is depicted as 72. Although this is not an exhaustive list of the systems used, it should provide you with the basis of understanding most systems. Regardless of the system, it must be flexible enough to record mixed dentitions as seen in juveniles (see Figure 7.2) As we saw with other parts of skeletal anatomy, there is a specialized terminology for indicating the orientation of structures. This is equally true for dental structures. For example, you may wish to describe the location of a lesion, such as a cavity (caries) (Fig. 7.3), on a particular tooth surface. If that cavity is on the biting surface would you call it the superior surface if it is on one of the mandibular teeth? What if it was on one of !he ~axillary teeth, then would you say Infen or? Another problem is that as you proceed along the dental arch you will notice that this semicircular arrangement actually means the surfaces of the teeth change relative to one another as you move along. Specifically, what may be considered in normal anatomical terminology to be the anterior surface of a central incisor may have quite a different location on a second molar. In order to get around this problem, odontologists have developed their own system for directional terminology that is based on the anatomical terminology that you have already learned. The key to using their system is to remember that the basis for the terminology is that all the terms are relative to the dental arch. Think of the dental arch as a railway track; you cannot move along unless you stay on the track. The same is true of the anatomical terms for teeth. The basic terms and definitions are as follows:

Dentition

1. mesial - refers to surfaces of the tooth oriented toward the median plane along the dental arch. 2. distal - opposite to mesial; refers to surfaces of the tooth oriented away from the median plane along the dental arch. 3. lingual - refers to structures that are oriented toward the tongue. That is to say, the tongue side of the tooth. 4. buccal/labial - these two terms are related. The fIrst of these terms refers to the surface of the tooth that is adjacent to the cheek. The second of these terms refers to the surface of the tooth that is adjacent to the lips. 5. occl usa I - refers to the surface of the tooth that is in contact with the teeth of the opposite jaw when the mouth is closed. Figure 7.4 demonstrates the application of these terms to a lower right first molar (M 1) , a lower left second incisor (21) and, for the occlusal surface, a lower left third molar

GM). Exercise 7.2: Using your text and lecture notes provide the dental inventory of the specimen provided by your laboratory instructor. Be sure to use the system indicated by your instructor. C . Identification of Individual Teeth

Identification of teeth is usually quite easy if they are maintained in the alveolus of the maxillae and mandible. However, in cases when isolated teeth are found, assessment can prove to be quite vexing. Identification of these isolated teeth depends on the accurate assessment of such features as shape, size, number of cusps, and number of roots. Many references have their own schemes for identifying individual teeth (e.g., Anderson, 1962; Bass, 1987; Steele and Bramblett, 1988; Schwartz, 1995; White and Folkens, 2000). Rather than reproducing any of these systems here we will outline some basic steps that are covered by Bass (1987):

107

Exercise 7.3: Using your text and lecture notes, identify as closely as possible each of the isolated teeth that have been provided to you by your instructor. D . Dental Variation All humans are said to exhibit the same general features, however, the phrase "normal variation" actually denotes a range of expression of a particular trait. This is particularly true of the human dentition. For instance, the adult human is supposed to have three permanent molars in each quadrant, however, the third molars are often absent (Fig. 7.5). This condition is common enough to be considered well within the limits of normal variation. In this example we have demonstrated a condition known as congenital absence. Again, the third molars are the most common teeth to be congenitally absent, however, other teeth may also be absent. It is important to be a?le to make the distinction between congenital absence and antemortem tooth loss with healing (Fig. 7.6). If the tooth was present at one time it may have left wear facets on the mesial or distal surface of an adjacent tooth. Just as one can have teeth missing, there are also instances of extra teeth. These are

108

Human Skeletal Anatomy

known as supernumerary teeth. These can occur in both adult and deciduous dentitions. One of the most common causes of supernumerary teeth is the retention of deciduous teeth in the adult dentition.

Additional cusps are yet another fonn of

Teeth can sometimes occupy the right location in the dental arcade, but not in the proper orientation. Teeth can be rotated so that a surface that is normally mesial is now lingual. In essence the tooth has pivoted around the long axis of the root. Another condition related to this is known as heterotopism. A heterotopic tooth has also been rotated, however, it is growing in the wrong direction. There are rare instances in which the crown of a tooth is erupting out of the anterior surface of the maxilla adjacent to the nasal cavity (Figure 7.7).

1. Protostylid - one extra cusp on the

Crowding of teeth is a fairly common occurrence in many populations. Crowding reflects the evolutionary conservatism of teeth in relation to the alveolar bone of the dental arch. Crowding of teeth is simply the result of teeth that have been pushed out of their usual position. The most common example of this is with third molars (i.e., impacted molars). To this point we have only outlined the variation in the number and positions of teeth in the arcade. However, teeth themselves demonstrate variation in their structure. The actual arrangement of cusps, both in number and position, should be recorded by the analyst. This has been done in order to explore population relationships. Briefly, the cusps, separated by grooves, should be counted in the mandibular and maxillary molars. Mandibular molars will usually demonstrate 4 or 5 cusps. In the maxillary molars, there are usually 3 or 4 cusps. However, the arrangement of these cusps is also of interest to us. In the mandibular molars the cusps are arranged in either a Y or + pattern. The Y5 pattern is an ancient one that has been seen in fossil primates. However, the other cusp patterns, Y4, +5 and +4 are more recent (Bass, 1987).

dental variation. These are generally found on the maxillary and mandibular molars. These cusps are defined as follows: mesial aspect of the buccal surface of the mandibular molars. 2. Carabelli's Cusp - a tubercle located on the mesial aspect of the lingual surface of maxillary molars. Expression ranges from a pit (Carabelli's Pit) to a fully developed cusp.

Shovel-shaping of incisors has a particularly high frequency in Mongoloid populations. The lingual surface of the incisors demonstrate an extension of the lateral borders. There may also be a related lingual fossa between these two extensions. Although there are many more dental features, these are some of the most commonly encountered in the osteological literature.

Exercise 7.4: Using your text and lecture notes, assess the cusp pattern of each of the mandibular molars in Figure 7.8 of your lab report. E. Dental Calcification and Eruption The development of teeth is of interest to odontologists and anthropologists because it can be a very accurate means of determining an age estimation. The process of dental calcification (the formation of teeth in the alveolus), and dental eruption (the appearance of a tooth on the occlusal plane) have been studied in order to provide aging standards. Ubelaker (1989) produced a chart showing eruption standards from in utero to age 35 years in American Indian populations. Dental calcification standards have also considered the fonnation of the crowns and roots of various teeth (see Moorrees, Fanning and Hunt, 1963a,b).

109

Dentition

Exercise 7.5:

Using your text and any additional materials provided to you by your instructor (such as models), record the eruption times for each tooth in the deciduous and permanent dentitions.

F . Microscopic Dental Tissue

Identification

0

f

Examine thin sections of teeth under the microscope. Identify and draw: Enamel, Dentine, and Cementum. Note that you should be able to identify from a diagram the following features: 1. enamel - the hard, mineralized layer that covers the dentine of the crown; it is nonliving. 2. dentine - hard, calcified tissue layer found just deep to the enamel or cementum. 3. cementum - the outside layer of the tooth found below the gumline that corresponds with the enamel. 4. gingiva (gum) - mucous epithelium covering the alveolar processes of the maxillae and mandible. 5. pulp chamber - central cavity within the tooth, filled with connective tissue; it provides passage of nerves and blood vessels. 6. alveolus - the socket of bone in the maxillae or mandible with which the tooth articulates. 7. periodontal ligament - fibrous connective tissue anchoring each tooth to the alveolus. 8. apical foramen - opening through the apex of the root of the tooth to allow passage of nerves and blood vessels 9. crown - superior most portion of the tooth. 10. neck - narrow portion of the tooth, below the crown. 11. root - long process(es) of tooth articulating with the alveolus.

Exercise 7 .6:

Label the diagram of a longitudinal section of a molar in Figure 7.9.

G. Dental Pathology As teeth are composed of various different tissues, it stands to reason that these tissues have the potential to develop various forms of pathology. Dental attrition is the wear that occurs on the occlusal surface of a tooth due to mastication. Any gritty foods or other particles can act as an abrasive and will wear down the cusps. The rate of attrition is as variable as the dietary components. As a result, many past populations have demonstrated more extreme cases of dental attrition than in contemporary populations. Dental attrition has been used as a means to provide an age at death estimate in some populations (e.g., Brothwell, 1965). However, it should be stressed that such an aging technique would not be equally applicable to all populations. Dental caries are likely the most familiar dental pathology to most people. Caries are essentially a decalcification of enamel, and subsequently, the underlying dentine (see Figures 7.3 and 7.5). Often related to caries are dental abscesses. An infection of dental tissues, such as the periodontum, can result in the formation of a pus cavity in the alveolus. This infection may lead to the creation of an opening (or cloaca) that permits the passage of pus out of the alveolus. Abscesses will often be concentrated around the apex of a tooth. Radiographically, abscesses have a halo appearance due to the formation of the pus cavity. A caries may proceed to the pulp of a tooth and result in an infection that develops into an abscess. Dental calculus is the mineralization of dental plaque on the surlace of a tooth. In some instances the calculus can cross over from one tooth to another. One final condition to consider is known as dental enamel hypoplasia. This condition is a defect in the development of enamel. Hypoplastic lesions can appear as pits, lines or grooves on the dental crowns. They result from an interruption of the formation of enamel in a developing tooth crown. This interruption of amelogenesis is due to some metabolic disturbance such as dietary insufficiency, infection, or even a fever. It is also important to note that there

110

Human Skeletal Anatomy

may be intentional modifications made to teeth. Consequently, one should consider that missing teeth, alterations, and pathology may have a significant cultural component. H . Laboratory Research Report: Examine the x-rays provided by your instructor, or use the ones in Fig. 7.10, and

evaluate each of the teeth you observe to be either in a crypt or erupting out of the crypt into the occlusal plane using the system indicated by your instructor. Your discussion should outline the applicability of this system for age at death determination. Compare at least two systems of determining age based on dental remains.

Dentition

111

Figure 7.1: Occlusal view of permanent maxillary dentition demonstrating the dental formula of 2-1-2-3 for the upper left quadrant of the mouth.

Figure 7.2: The mixed dentition of a 7-year-old. There are several adult teeth in the process of erupting in addition to the presence of various deciduous teeth.

112

Human Skeletal Anatomy

Figure 7.3: Distal view of an upper premolar with a large carious lesion. Note the amalgam filling directly over the caries.

Dentition

Figure 7.4: Occlusal view of the permanent mandibular dentition showing the anatomical terminology of the various dental surfaces. '

113

114

Human Skeletal Anatomy

Figure 7.5: Mandiblular dentition demonstrating many carious lesions and postmortem tooth loss. Note that the third molars were either lost antemortem or are congenitally absent.

Dentition

Figure 7.6:

115

Edentulous maxillae demonstrating total alveolar resorption. Note that one tooth was retained in life as evidenced by the tooth root sockets in the upper left of this individual's alveolus.

116

Human Skeletal Anatomy

Figure 7.7: A radiograph of a nonsupemumerary heterotopic upper right canine rotated so that the occlusal surface is oriented in the position normally occupied by the root (see arrow). The result was that the tooth was erupting out of the right maxilla adjacent to the right nasal margin (Fairgrieve and Bashford, 1987).

117

Dentition

Exercise: 7.1

:11::::::::·::::::·::::·:···.::·II.¢.~.ll.ld~·:,'::':::::"::·:·:::I:··:II::·::::·::.:I:I~i_I~It,I:I:':·:.:I:I::·11'::::::.:; ~~~1~~~+~~[~~1~6:mbi~t~[~~~j~Qf~~j~j~Xn~i$Qr$~~~j~t~~~~~:

·1:·:::::::::··.:i:.::.l:::ll·i:::·:::i1::I·il.ili 1:i:1:·::·:::i:::i:·:1.1:·:i:::i::l:::·:: :::i:::l·i:··::':·::···::'::·i·ilijil&li:!.·,:·:i:i:i::;:i:'i·i··i. :::':::::::.:·:::::I,:·::i:::i,,:,:,:::,'·II'lt$.:'::::·:i·:·:·:i':·::::i·:,·.· :····:::··::::::::i:·:::i::I~I~:·lf::::tl(lll:::: :·:i:i·.::·::'I~litit·;::i&f.::::llimll··::i:,·,:·::::i:::

Exercise: 7.2 Using the system outlined by your instructor, provide an inventory of the dentition of the assigned skull utilizing the grid below. Record the specimen identification number if applicable. (see next page for Exercise 2b).

Upper Right

Upper Left

Lower Right

Lower Left

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Human Skeletal Anatomy

Exercise: 7.3 Identification of Individual Teeth

Exercise: 7.4

Figure 7.8: Occlusal view of permanent mandibular molars. What is the cusp pattern of the mandibular molars of the provided specimen?

M ------------

M3

3

M2

2M

M1

1

------------

M ------------

Exercise: 7.5

Dentition

119

Exercise: 7.6

Figure 7.9: Longitudinal section of an upper premolar. 1.

6.

2.

7.

3.

8.

4.

9.

5.

_

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Human Skeletal Anatomy

RESEARCH REPORT #7

Figure 7.10: Lateral radiograph of dentitions (A and B) for developmental assessment of indicated teeth in crypts. Note that in radiograph A there is a supernumerary tooth erupting through the incisive foramen" Provide your assessment of the development of teeth listed below for each radiograph. Radiograph A:

Radiograph B:

3M:

3M:

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Nonmetric Variation

NONMETRIC VARIATION INTRODUCTION Up to this point we have been studying "normal" skeletal anatomy. Further, it should be obvious that there is no such thing as a "normal" skeleton (or at least it would seem). In fact, the one constant in characterizing any skeletal population is variation. This laboratory is designed to familiarize you with the more commonly noted nonmetric traits (cranial and infracranial). Nonmetric traits are broadly divided into two groups, Discrete/ Discontinuous traits (those that are either present or absent) or Continuous/ Qualitative traits (when present, are variably expressed). In order to effectively appreciate the range of variation, you must look at other skeletal remains in the lab. Both the cranial and infracranial skeleton will be evaluated. Discrete traits can be used as a measure of biological distance between groups. However, continuous morphology can also be used as a measure of sexual dimorphism (thus aiding in sex determination).

PURPOSE This lab will familiarize you with nonmetric skeletal variation, and its application to age, sex, and genetic affiliation.

BEFORE YOU BEGIN • • •

Read the suggested chapter in your text book and relevant lecture notes. Understand the objectives for this exercise. Familiarize yourself with the terms in the IMPORTANT TERMS list, for testing purposes.

OBJECTIVES At the end of this lab you will be able to: • identify and score discrete and continuous traits found on cranial and infracranial skeletal elements.

MATERIALS • •

articulated human skull disarticulated human infracranial skeleton

PROCEDURE A. CRANIAL NONMETRIC VARIATION Discontinuous/Discrete Traits There have been as many as 200 nonmetric traits described for the skull alone. This arose out of the preoccupation of the skull by early physical anthropologists in the late 1800s. These types of traits are scored as either being present (P) or absent (A). These traits should only be scored in mature individuals as several of them, such as the tympanic dehiscence, may be present in younger individuals but disappear with maturation. It is important for you to become accustomed to reading detailed anatomical descriptions and understanding what they mean. This is one reason we have been stressing the use of proper anatomical terminology. Below we have defined several discrete traits of the skull. In addition to these descriptions we have also included a series of diagrams adapted from Molto (1983) to aid in the descriptions of traits 127. The remaining traits require you to read the descriptions carefully. 1. Os japonicum: the zygomatic bone is divided by a transverse suture resulting in two segments. Any trace suture should be used to score this trait as present. 2. Infraorbital suture: a suture running from the infraorbital foramen to the edge of the orbit on the facial surface. Any trace is scored as present. This trait is in fact not a true suture.

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Human Skeletal Anatomy

3. Tympanic dehiscence: any hole that exists in the medial one-third of the tympanic plate. 4. Open spinosum: any error in bone formation in foramen spinosum and the sphenotemporal petrous. All defects, complete or partial are scored as present. 5. Mendosal suture: bipartition of the squama of the occipital bone, from the left and right aterian landmarks. Any trace is scored as present. 6. Marginal foramen: a small circular foramen on the lateral, inferior surface (margin) of the external auditory meatus. Only a complete foramen is scored as present. 7. Spinobasal bridge: a bony spur or bridge arising lateral to foramen spinosum and pointing medially. 8. Pterygobasal bridge: a bony spur or bridge arising near the anterio-lateral margin of foramen spinosum and pointing anterio-medially. 9. Divided hypoglossal canal: any complete or incomplete bony septum (or septa) creating an internal division of the hypoglossal canal. 10. Ossified apical ligament (occipital): the ligament that connects the dens to the inside of the skull, i.e., anterior margin of the foramen magnum. Any spur is scored as present. 11. Intermediate condylar canal: a groove along the lateral margin of the occipital condyles. Any complete roof is scored as present. 12. Clino-clinoid bridge: A bridge of bone that joins the anterior and posterior clinoid processes. 13. Carotico-clinoid bridge: A bony bridge of bone that joins the anterior clinoid process to the middle clinoid process. 14. Trochlear spur: A tiny spur situated in the superiomedial margin of the orbit. It is an ossification of the trochlea. Any spur is scored as present. 15. Parietal foramen: A small but distinctive foramen in the parietal bone near the sagittal suture. It is usually situated four to seven centimeters anterior to

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Nonmetric Variation

16.

17.

18.

19.

20.

lambda. This trait is scored as present if any hole or holes passes through both the inner and outer tables. Posterior condylar canal: This trait is positioned just posterior to an occipital condyle. If it is a complete passage, score the trait as present. Frontal grooves: These grooves, or shallow, narrow channels are found on the outer table squama of the frontal bone. Typically, they are found just medial to the temporal line or crest. Supraorbital foramen: This trait was mentioned in Laboratory 6; it is any foramen connecting the roof of the orbit to the external surface of the frontal bone. Zygomatico-facial foramen: This foramen runs from the floor of the orbit to the external surface of the zygomatic bone. This foramen may occur multiply. Parietal process of temporal: This trait is characterized by grooves that appear to be emerging from the superior border of the squamosal suture on the parietal bone.

21. Accessory

optic

canal:

25. Occipito-mastoid ossicle: 26. 27.

28.

29.

An

additional penetrating canal that is adjacent to the optic canal. 22. Lambdic ossicle: This is any accessory ossicle that touches the cranial landmark known as lambda. Lambda is the midline point where the sagittal and lambdoidal sutures meet. Please note that this does not include an os inca which is the result of a complete mendosal suture. 23. Lambdoidal ossicle: This trait is distinguished from the lambdic ossicle by being any accessory bone that is in the lambdoidal suture. If the ossicle touches lambda or the landmark known as asterion it is not considered a lambdoidal ossicle. 24. Asterionic ossicle: This is any accessory bone that touches the cranial landmark known as asterion. Asterion is the point of confluence between the lambdoidal, parietomastoid, and occipitomastoid sutures.

30. 31.

This is any bone found to occur in the occipitomastoid suture. Parietal notch ossicle: This is any accessory bone found within the parietal notch of the squamosal suture. Pterionic ossicle: This is an accessory bone that touches the cranial landmark known as pterion. Pterion is a region defmed as being the area where the frontal, parietal, temporal and sphenoid bones meet. Due to the highly variable nature of the sutures in this area it cannot be reliably defined as a precise point. Vesalian foramen: This trait is characterized as an accessory foramen located internally between the foramen ovale and the foramen rotundum. When looking for this in the basal aspect of the cranium, it will be located between the medial and lateral pterygoid plates. The foramen must pass completely through the bone in order to be recorded as present. Sagittal sinus left: This trait is located on the inner table of the cranial vault. One must insert a finger into the foramen magnum and palpate the region of the internal occipital protuberance. In this area you will feel a deep, curved channel for the sagittal sinus. If the deeper and larger channel palpated turns left, then the trait is scored as present. Mylohyoid arch: This trait is found on the mandible. It appears as a bony bridge over the mylohyoid groove. Multiple mental foramina: This trait is also found on the mandible. It appears as any accessory foramen found in the vicinity of the mental foramen.

Traits numbered 22 through 27 have been confused by some as wormian bones when they are, in fact, sutural accessory bones. Wormian bones are actually much smaller than sutural accessory bones and appear as isolated recurved areas in a suture. Some researchers have casually described wormian bones as sutural switchbacks. Nonetheless, wormian bones are distinct

124

Human Skeletal Anatomy

from the sutural accessory bones that have been described here.

Exercise 8.1: Score the listed traits as either present ("P") or absent ("A") on your assigned skull. Note that you must score these traits (where possible) from both the left and right sides of the skull. Some traits are found in the midline and therefore, lack bilateral expression. As your assigned skull will likely lack many of these traits, do look at other skulls that have been assigned to other students in order to observe traits not evident on your study specimen.

2.

3.

Continuous/Qualitative Traits Unlike the last set of cranial traits, these traits cannot be scored on the basis of being present or absent. The traits defined below are known as continuous or qualitative traits because there is variability in their expression. One skull may demonstrate a slight expression of a trait, whereas, another skull will have an extreme expression of the trait. Given that in mature individuals the skull is to varying degrees sexually dimorphic, many continuous traits are used as a basis for assessing the sex of the individual if the os coxa is not available. It should be stressed that certainly the skull is not ignored if the os coxa is present, however, the use of the skull's continuous morphological traits as a basis for sex determination is generally second to the os coxa. It should be cautioned that the use of sexual dimorphism of the skull as a basis for sex determination should only be done on a comparative basis from within the same genetic popoulation. If one were to examine an archaeological European adult male skull and compare it to an archaeological Inuit female skull, the latter of these would appear much more robust and could be wrongly interpreted as male. All of these traits are commonly described in most osteological texts, however, we will define them here: 1. Brow ridges: These are also known as supraorbital ridges. They occur in the supercilliary region on the frontal bone

4.

5.

6.

7.

directly superior to the orbits. They are generally larger in males than in females of a given population. They are scored using a plus scale. Mastoid process: The mastoid process is a feature of the cranial vault we discussed in Lab 6. The mastoid process is also a sexually dimorphic trait that is generally larger and more heavily muscle marked in males than in females. Use a plus scale for scoring. Malar tubercles: The term malar is an old one meaning the zygomatic bone. The malar tubercle is a rough eminence found on the facial surface of the zygomatic bones. A plus scale is used for scoring. Temporal line: This is another feature discussed in Lab 6. The temporal line can be very well defined in some individuals. It is essentially a measure of the robusticity of the origin of the temporalis muscle that is used in mastication. A plus scale is used for scoring. Nuchal crest: You will recall nuchal lines from Lab 6. The nuchal crest is of the nuchal muscle markings in the area around the external occipital protuberance. Again, this feature is generally more robust in males than in females of the same population. A plus scale for robusticity is used to score this trait. Palatine torus: Along the articulation of the palatine processes of the left and right maxillae known as the palatine suture. The bone running along the palatine suture can appear as having been accumulated to form a ridge. That ridge is referred to as the palatine torus. It has been found that individuals of European descent tend to have a larger palatine torus. As such you will score this trait using a plus scale. Paramastoid tubercle: The term "paramastoid" literally means around or beside the mastoid. As such, the tubercle is found as a bony eminence emerging from the jugular process. A plus scale is used to score the size of the tubercle. In

125

Nonmetric Variation

some cases the paramastoid tubercle can be so large that it actually articulates with the atlas (Cl). In that case the score would be ++++. 8. Chin form: This trait does not use a plus scale for scoring the trait. Instead this trait is recorded by noting the various forms that occur. A chin can have a median or mid-sagittal eminence; be bilateral and have two eminences on either side of the median plane; or a combination of these two known as a median-bilateral chin. 9. Gonial eversion: Gonion is a landmark that is defined as being a point on the mandible that is located on the posterioinferior comer between the body and the ascending ramus. In this area the bone can exhibit a lateral flare. This flaring can be quite extensive and has been found to be most extreme in Inuit populations. This trait is scored using a plus scale. You will note that because these traits are continuous in nature, again, meaning present to a degree, we cannot evaluate them simply as being present or absent. In this case many osteologists use a plus or an ordinal scale. For example, a skull may demonstrate very large brow ridges for that population. If they are the largest/most robust you have in the collection, then you could confidently assign a score of ++++ or 4 (depending on the scale). A skull with slight brow ridges would be scored as + or 1. A person with no brow ridges would be scored as O.

Exercise 8.2: Score the listed traits using the plus scale on an assigned skull. Note that the convention is that you must score these traits (where possible) from the left side of the skull. If that is not possible score them on the right side, however, indicate the cases in which this is done. As with the last exercise you should also look at the other skulls assigned to your colleagues in the lab in order to look at the range of expression of these traits.

B. INFRACRANIAL VARIATION

NONMETRIC

Discontinuous/Discrete Traits Many of the general comments made in section A apply to discrete traits of the infracranial skeleton. However, in this instance these traits are scored as present or absent on bones from the vertebral column, sternum, upper limb, and lower limb. Although it is beyond the scope of this laboratory manual to go over all of the infracranial traits that have been described, we will present to you a brief list of those that have been frequently cited in the literature. Unfortunately, we are not able to provide as extensive diagramatic representation of these traits as was done in section A. However, we are providing detailed descriptions of each of these traits. You will need to look for each of these traits in your laboratory session. Again the practice will be to score the traits as either present ("P") or absent ("A") from the assigned infracranial skeleton. 1. Posterior bridge (Cl): This trait is characterized by a deep groove that occurs immediately posterior to the superior articular facet and is sometimes covered by a bridge of bone. Any bridge or spur indicates presence of this trait. 2. Lateral bridge (Cl): This trait occurs as a bridge of bone or spur between the superior articular facet and the transverse process. 3. Posterior arch foramen (Cl): This is a notch or foramen on the external edge of the posterior arch, just posterior to the transverse process. 4. Ossified apical ligament (C2): This is a spur of bone that occurs on the apex of the dens of C2. You must be careful not to mistake this trait for artluitic lipping. 5. Multiple transverse foramina (C3C7): This is any variation in the number of transverse foramen beyond the typical one foramen on each side. This should be recorded for C3-C7.

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Human Skeletal Anatomy

6. Multiple transverse foramina (C4): see trait 5. 7. Multiple transverse foramina (C5): see trait 5. 8. Multiple transverse foramina (C6): see trait 5.

this condition as it can be a lifestyle indicator. The defect appears as a separation of the neural arch from the rest of the vertebra. The spinous process (particularly in archaeological specimens) may be missing. This is usually bilateral and it can appear as if the spinous process has been broken off. Any division between the superior and transverse processes is counted as present. 11. Sacralization of L5 (sacrum): As the term suggests, this is a fusion of L5 to the sacrum. This fusion is commonly bilateral and may be complete. In cases of complete fusion you need to count the number of sacral segments and then to examine the margins of the alae to see if they are sloping at a greater angle. In order to evaluate this condition you must also check to see if the coccygeal segments have fused to the sacrum as this may account for the increased number of segments rather than L5 sacralization. Score any fusion of L5 as present. 12. Sternal aperture (sternum): This is a round hole that occurs in the middle of the sternal body. Typically it is between the third and fourth segment.

13. Acromial

epiphysis

(scapula):

This trait is characterized as a division of the acromion resulting in an acromion that appears incomplete when all other scapular epiphyses are fused.

14. Suprascapular foramen (scapula):

9. Multiple

transverse

foramina

(C7): see trait 5.

10. Spondylolysis (L5):

This trait has recently been argued to actually be due to stress on L5 as opposed to a discrete trait. As such it is likely due to the habitual practice of flexing the spinal column for harvesting and other activities. However, you should score

This trait is located medially to the coracoid process along the superior border of the scapula. It appears as a scapular notch that has a complete bridge of bone across its superior border, thus forming a foramen. The trait is scored as present with either a complete bridge of bone or an incomplete bridge with spurs. 15. Septal aperture (humerus): This is a hole/foramen connecting the olecranon fossa to the coronoid fossa. In order for this trait to be scored as present, direct light must be visible through the foramen. This trait has been suggested

Nonmetric Variation

16. 17.

18.

19. 20.

21.

by forensic anthropologists to occur more frequently in females than in males. However, this should not be considered as a trait diagnostic of female remains. Third trochanter (femur): This is a large rounded protuberance that is found on the gluteal tuberosity of the femur. Fossa of Allan (femur): This trait is scored as present if there is any distinct depression on the anterior surface of the neck of the femur. This has been described as having the appearance of a depression on the bone the size of a thumbprint. Vastus notch (patella): This is any notch present on the superiolateral margin of the patella (see Figures 5.8 and 5.9). Squatting facet (tibia): This is any anterior extension of the distal articular surface of the tibia. Os trigonum (talus): This is a posterior tubercle on the talus. This tubercle has its own center of ossification. Conjoined facets (calcaneus): This is any occurrence of a continuity (or connection) of the anterior and middle facets of the calcaneus.

Exercise 8.3: Score the listed traits as either present ("P") or absent ("A") from an assigned infracranial skeleton. Note that you must score these traits (where possible) from both the left and right skeletal elements. Some traits are found in the midline and therefore, lack bilateral expression. Again, be sure to look at other skulls that have been assigned to other students in order to observe traits not evident on your study specimen. continuous/Qualitative Traits As was the case with the continuous traits of the skull, similarly, the continuous traits of the infracranial skeleton are generally scored using a plus scale. A few of the traits listed below will require you to categorize a feature as conforming to a particular description.

127

1. Costal tuberosity (clavicle): This feature was described in Lab 4. The costal tuberosity can demonstrate variation in robusticity. This trait is evaluated using a plus scale. 2. Conoid tuberosity (clavicle): This feature was described in Lab 4. The conoid tuberosity can also demonstrate variation in robusticity. This trait is evaluated using a plus scale. 3. Vertebral border (scapula): In this case the fonn of the border is either convex, concave, or irregular.

4. Deltoid tuberosity (humerus): This feature was previously described in Lab 4. The size and robusticity is evaluated using a plus scale. 5. Tuberosity spur (radius): The radial tuberosity was described in Lab 4. The degree of spurring of the tuberosity is evaluated using a plus scale. 6. Proximal spur (ulna): This trait is an evaluation of the degree of spurring of the posterior edge of the proximal end of the olecranon process. 7. Acetabulum (os coxa): The articular surface of the acetabulum may demonstrate various irregularities. These irregularities are recorded as being either pits, slits or grooves. 8. Patellar spur (patella): The anterior surface of the patella may have spurs in a superior-inferior orientation. The degree of spurring is evaluated using a plus scale. 9. Tuberosity spur (calcaneus): The calcaneal tuberosity may also demonstrate a degree of spurring. The degree of spurring is evaluated using a plus scale. Exercise 8.4: Score the listed traits using the plus scale on an assigned infracranial skeleton. Note that the convention is that you must score these traits (where possible) using elements from the left side. If that is not possible score the corresponding right element, however, indicate the cases in which this is done. Remember to look at other infracranial skeletons assigned to your

128

Human Skeletal Anatomy

colleagues in the lab in order to look at the range of expression of these traits.

C . LABORATORY RESEARCH REPORT

Using the continuous traits of the skull assess the specimen provided in your lab for its sex.

Your discussion should deal with the fact that sexual dimorphism will be variably expressed in certain traits from one population to another (Bass, 1987). As such, some traits will prove to be more useful than others for sex determination.

Nonmetric Variation

129

20 17

23

19

27

20

17

Figure 8.1: Right and left aspects of the skull demonstrating traits 1, 3, 5, 6, 8, 11, 14, 17, 19, 20, 23, 24, 25, 26, and 27 (Courtesy of I.E. Molto).

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Human Skeletal Anatomy

17

Figure 8.2: Frontalis view of the cranium demonstating traits 2, 14, 17, 18, 19, and 21 (Courtesy of I.E. Malta).

131

Nonmetric Variation

~.......;;;;;;~-15

26

24

24

15

22

Figure 8.3: Posterior and superior aspects of cranium demonstrating traits 5, 15, 17, 22, 23, 24, 25, and 26 (Courtesy of I.E. Malta).

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Human Skeletal Anatomy

Figure 8.4: Inferior aspect of the cranium demonstrating traits 3, 4, 6, 7, 8, 9, 10, 11, and 16 (Courtesy of J.E. Molto).

133

Nonmetric Variation

Superior

View of Sphenoid

Figure 8.5: Molto).

Superior view of the sphenoid demonstrating traits 12 and 13 (Courtesy of J.E.

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Human Skeletal Anatomy

NONMETRIC TRAITS

Exercise 8.1

Nonmetric Variation

Exercise 8.2

135

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Exercise 8.3

Nonmetric Variation

Exercise 8.4

137

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Human Skeletal Anatomy

OSTEOMETRIes

• •

INTRODUCTION The measurement of human skeletal remains is yet another way to chronicle ~ariati?n. As with the recording of nonmetnc traits, the measurement of skeletal elements has been used to assess biological distance between groups. Although, according to some authors less reliable in that regard, much of osteom~trics has an important role to play in the forensic analysis of the skeleton. Measurements of unknown specimens can be compared to those values taken from known samples and, thus, may indicate .the sex, genetic ancestry, or even an estunate .of stature. These applications are fraug~t WIth problems as the leng~ of bones IS not dictated solely by genetic factors. Unknown modes of inheritance, including age progressive and regressive tende~cies, the plasticity of bone, and other envrronme~~ factors may all have an influence (EI-NaJJar and McWilliams, 1978: 112). Another limiting factor is the simple fact that we are trying to characterize co~plex ~ee­ dimensional objects by a senes of SIngle dimension measures. Subtle nuances of the morphology are certainly not recorded in these measurements.

PURPOSE This lab will acquaint you with various osteometric landmarks and measurements of the skull and infracranial skeleton, and demonstrate how they are used to calculate various indices that are used to describe the skeleton.

BEFORE YOU BEGIN • •

Read the suggested chapter in your text book and relevant lecture notes. Understand the objectives for this exercise.

Familiarize yourself with the IMPORTANT TERMS list, for testing purposes. . Familiarize yourself WIth the correct use and reading of the measurement apparatus.

OBJECTIVES At the end of this lab you will be able to: • locate various landmarks on the skull. • perform various descriptive measurements of the skull and infracranial elements. • calculate descriptive indices based on measurements.

MATERIALS • • • • •

•

articulated human skull disarticulated infracranial skeleton spreading calliper (SP) sliding calliper (SL) osteometric board (OB) measuring tape (Tape)

GENERAL PROCEDURES As mentioned in Lab #6, the cranium is relatively fragile, and should be handled with care at all times. As a general rule, one should have two hands on the skull whenever it is picked up. Further, a pad should be protecting the skull from hard surfa?es whenever possible (a bean bag or skull nng is ideal). The sliding caliper (SL) and the s~reading caliper (SP), utilized in this exercise, are delicate instruments. They should be treated gently. The accuracy of these instruments should be checked before use, and they should be put away after use.. Y?ur text defines several cranial osteometnc points that serve as points of reference or "landmarks" (see IMPORTANT TERMS). Th~~e must be reviewed in order to facilitate the measurement of the skull. The most vexing problem of craniometries is the location of these points. These should be understood

Osteometries

well before coming into the lab. COME W LAB PREPAREDI All measurements should be expressed in millimeters. It is also standard practice that all measurements be rounded to the nearest whole millimeter. Before one begins taking any measurements of skeletal elements, the analyst must follow several general rules. 1. Unless you are measuring a long bone diaphysis or any other element for aging or any other specific purpose, subadult

remains should not be measured. This is because they have not completed their growth and thus should not be used to characterize the population. However, you may wish to measure subadults in order to attempt to characterize different age cohorts. Although this raises the question about sexing subadult remains due to differing maturation rates of males and females. 2. Sexual dimorphism of male and female skeletal remains necessitates keeping them separate. You would usually be characterizing a sample of skeletons on the basis of sex. It is important to remember that no method for determining the sex of a skeleton or individual bone is 100 percent. Even DNA analysis can be problematic in highly degraded samples. 3 . In most instances the standard practice is to take the measurements from the left side of the body. This is only in cases in which both the elements from the left and right side are available. If the left side is not available, take the measurement from the right side and make note of this fact. 4. If you find that the bone you wish to measure exhibits some form of pathology, it is not valid to take that measurement. However, if you are trying to determine the effect of the pathology, such as the effects of a fracture, then a measurement can at least provide you with an estimate.

139

5 . As you will recall, skeletal elements exhibit a range of variation. Sometimes landmarks that have been described for the purpose of taking measurements do not conform to the definition. The classic example of this is the defmition for bregma. It is defined as the point where the sagittal and coronal sutures intersect. However, the sagittal suture can certainly deviate from the point of intersection away from the median plane. If that occurs this does not mean that you take the measurement at that exact point, but take it where the sagittal suture would have met along the median plane. It is often said that you should follow the spirit of the definition of the measurement. 6. You will find that taking measurements from skeletal material can initially be quite difficult. This includes becoming familiar with the definition of the measurement, finding the appropriate landmarks, utilizing the correct type of caliper, and finally taking the reading. As a result, you will need to practice taking the measurement so that you become more proficient. To measure this proficiency you must do an intraobserver error study. In this instance the same person who took the original measurements repeats the measurements after a prescribed period of time. This way you will be able to identify any of the measurements that are inaccurate due to any of the factors listed above. It is also desirable to have someone else take the same measurement in order to ascertain if there are any problems with the description of the method. This interobserver error study is a way of evaluating the reproducibility of the defined measurement. Remember, science demands the assurance of reproducibility of results. If the only person who can take a measurement or perform a specific procedure in order to get a certain result is the person who invented the method, then it is of little use in science.

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Human Skeletal Anatomy

take these measurements will depend on your understanding of the definitions of these landmarks. Most texts on human osteology will provide definitions of these landmarks (e.g., Bass, 1987; White and Folkens, 2000). The descriptions of the measurements based on these landmarks can also be found easily in the literature (e.g., Bass, 1987; Moore-Jansen et al., 1994). Although we have not provided the reader with the definitions of the landmarks in this manual, we have provided a series of photographs (Figures 9.1-9.4) showing the p.osition of each cranial landmark on which these measurements are based. However, it is important for you to consult your text for the definition of each landmark. Below we have provided definitions for .. each of. the craniometries. These definitions are denved from and follow the order found in MooreJansen et al. (1994).

7. In most instances it is usually the rule, rather than the exception, that a specimen you need to measure is broken. Typically, no measurement would be taken. However, statistical analysis demands a complete data set. In that case you may estimate the meas~ement. This estimation must be recorded In your datasheets.

PROCEDURE A. CRANIOMETRICS The various measurements of the skull are collectively known as craniometries. In order to take these measurements one must set each end of a caliper on specifically defmed points or landmarks. Your ability to

1. Maximum Cranial Length. (SP) Glabella to Opisthocranion. 2. Maximum Cranial Breadth. (SP) Euryon to Euryon. 3. Bizygomatic Breadth. (SP or SL) Zygion to Zygion. 4. Maximum Cranial Height. (SP) Basion to Bregma. 5. Cranial Base Length. (SP) Basion to Nasion. 6. Total Facial Height. (SL) Gnathion to Nasion. 7. Maxillo-Alveolar Breadth. (SL) Ectomolare to Ectomolare (this point is positioned on the most lateral surface of the alveolar crest, i.e., generally on the alveolar margin of the second maxillary molar (Moore-Jansen, et. al., 1994). 8. Maxillo-Alveolar Length. (SP or SL) Prosthion to Alveolon. 9. Biauricular Breadth. (SL) Auriculare to Auriculare. 10. Upper Facial Height. (SL) Alveolare to Nasion. 11. Minimum Frontal Breadth. (SL) Frontotemporale to Frontotemporale. 12. Upper Facial Breadth. (SL) Frontomalare temporalia to Frontomalare temporalia.

141

Osteometries

13. Nasal Height. (SL) Nasion to Nasospinale. 14. Nasal Breadth. (SL) Alare to Alare. I5.0rbital Breadth. (SL) Dacryon to Ectoconchion. 16. Orbital Height. (SL) Distance between the superior and inferior orbital margins. Perpendicular to orbital breadth. 17 . Biorbital Breadth. (SL) Ectoconchion to Ectoconchion. 18. Interorbital Breadth. (SL) Dacryon to Dacryon. 19. Frontal Chord. (SL) Nasion to Bregma. 20. Parietal Chord. (SL) Bregma to Lambda. 21. Occipital Chord. (SL) Lambda to Opisthion. 22. Foramen Magnum Length. (SL) Basion to Opisthion. 23. Foramen Magnum Breadth. (SL) Lateral margins of foramen magnum. 24. Mastoid Length. (SL) Mastoid process below eye-ear plane. 25. Chin Height. (SL) Gnathion to Infradentale. 26. Height of the Mandibular Body. (SL) At mental foramen. 27. Breadth of Mandibular Body. (SL) At mental foramen. 28. Bigonial Width. (SL) Gonion to Gonion. 29. Bicondylar Breadth. (SL) Condylion to Condylion. 30. Minimum Ramus Breadth. (SL) Least breadth perpendicular to height. 31. Maximum Ramus Breadth. (SL) Most anterior point on the mandibular ramus to the most posterior point on the condyle and the angle of the mandible. 32. Maximum Ramus Height. (SL) Gonion to highest point on condyle. 33. Mandibular Length. (mandibulometer) 34. Mandibular Angle. (mandibulometer or goniometer).

Exercise 9.1: Using the skull assigned by your instructor, provide each measurements decribed above.

Exercise 9.2:

of

the

Using the measurements taken in Exercise 9.1, calculate the required indices listed for this exercise. Note that the

formula for each index uses the number of each measurement to be utilized.

B. INFRACRANIOMETRICS The following measurements are a selected few of those utilized by osteologists. This should by no means be considered an exhaustive list. However, these measurements are amongst the most commonly taken on archaeological and forensic specimens. The majority of these measurements are taken using an osteometric board (OB). The numbering of these measurements follows that in Moore-Jansen et aL (1994). Once again, be sure to measure to the nearest whole millimetre. If a measurement is exactly half-way, round it to the nearest even number. The definitions of these measurements are drawn from Moore-Jansen et aL (1994). 35. Maximum Length of the Clavicle. (OB) The maximum distance between the most extreme ends of the clavicle.. 36. Sagittal Diameter of the Clavicle at Midshaft. (SL) The anterior-posterior distance from the surface of the midshaft. This measurement is usually the maximum diameter at the midshaft. 37. Vertical Diameter of the Clavicle at Midshaft. (SL) The distance from the cranial to the caudal surface of the mid shaft. 38. Height of the Scapula. (SL) The direct distance from the most superior point of the cranial angle to the most inferior point on the caudal angle. 39. Breadth of the Scapula. (SP) The distance from the midpoint on the dorsal border of the glenoid fossa to midway between the two ridges of the scapular spine on the vertebral border. 40. Maximum Length of the Humerus. (OB) The direct distance from the most superior point on the head of the humerus to the most inferior point on the trochlea. 41. Epicondylar Breadth of the Humerus. (OB/SL) The distance of the most laterally protruding point on the lateral

142

Human Skeletal Anatomy

epicondyle from the corresponding projection of the medial epicondyle. 42. Maximum Vertical Diameter of the Head of the Humerus. (SL) The direct distance between the most superior and inferior points on the border of the articular surface. 43. Maximum Diameter of the Humerus at Midshaft. (SL) Determine the midpoint of the diaphysis on the osteometric board. The midpoint is generally located a few millimeters below the inferior margin of the deltoid tuberosity. Tum the bone until the maximum diameter is obtained. 44. Minimum Diameter of the Humerus at Midshaft. (SL) Determine the midpoint of the humerus on the osteometric board. Tum the bone until the minimum diameter is determined. 45. Maximum Length of the Radius. (OB) The distance from the most proximally positioned point on the head of the radius to the tip of the styloid process without regard to the long axis of the bone. 46. Sagittal Diameter of the Radius at Midshaft. (SL) The anterior-posterior diameter of the midshaft. This measurement is almost always less than the transverse diameter. 47. Transverse Diameter of the Radius at Midshaft. (SL) The distance between the maximum medial and lateral bone surfaces at the midshaft. 48. Maximum Length of the Ulna. (OB) The distance between the most superior point on the olecranon and the most inferior point on the styloid process. 49. Dorso-Volar Diameter of the Ulna. (SL) The maximum diameter of the diaphysis where the crest exhibits the greatest development. 50. Transverse Diameter of the Ulna. (SL) The diameter measured perpendicular to the Dorso-Volar diameter at the level of greatest crest development. 51. Physiological Length of the Ulna. (SP) The distance between the deepest point on the surface of the coronoid process and the lowest point on the inferior surlace of the distal head of the ulna. Do not include the styloid process or the groove

between the styloid process and the distal surface of the head. 52. Minimum Circumference of the Ulna. (Tape) The least circumference near the distal end of the bone. 53. Anterior Height of the Sacrum. (SL) The distance from a point on the promontory in the midsagittal plane to a point on the anterior border of the tip of the sacrum measured in the midsagittal plane. 54. Anterior Breadth of the Sacrum. (SL) The maximum transverse breadth of the sacrum at the level of the anterior projection of the auricular surfaces. 55. Transverse Diameter of Sacral Segment 1. (SL) The distance between the two most lateral points on the superior articular surface measured perpendicular to the midsagittal plane. When lipping of the articular surface is present, approximate the original articular borders. 56. Height of the Os Coxa (Innominate). (SP or OB) The distance from the most superior point on the iliac crest to the most inferior point on the ischial tuberosity. 57. Iliac Breadth. (SP) The distance from the anterior superior iliac spine to the posterior superior iliac spine. 58. Pubis Length. (SL) The distance from the point in the acetabulum where the three elements of the innominate (os coxa) meet to the upper end of the pubic symphysis. 59. Ischium Length. (SL) The distance from the point in the acetabulum where the three elements forming the innominate meet to the deepest point on the ischial tuberosity. 60. Maximum Length of the Femur. (OB) The distance from the most superior point on the head of the femur to the most inferior point on the distal condyles. 61. Bicondylar Length of the Femur. (OB) The distance from the most superior point on the head of the femur to a plane drawn along the inferior surfaces of the distal condyles. 62. Epicondylar Breadth of the Femur. (OB) The distance between the two most

Osteometries

laterally projecting points on the epicondyles. 63. Maximum Diameter of the Head of the Femur. (SL) The maximum diameter of the head of the femur measured on the border of the articular surface. 64. Sagittal Subtrochanteric Diameter of the Femur. (SL) The anterior-posterior diameter of the proximal end of the diaphysis measured perpendicular to the transverse diameter at the point of the greatest lateral expansion of the femur below the lesser trochanter. 65. Transverse Subtrochanteric Diameter of the Femur. (SL) The transverse diameter of the proximal portion of the diaphysis at the point of its greatest lateral expansion below the base of the lesser trochanter. 66. Antero-Posterior (Sagittal) Diameter of the Femur at Midshaft. (SL) The anterior-posterior diameter measured approximately at the midpoint of the diaphysis, at the highest elevation of the linea aspera. This measurement is taken perpendicular to the ventral surface. 67. Transverse Diameter of the Femur at Midshaft. (SL) The distance between the medial and lateral margins of the femur measured perpendicular to, and at the same level as, the sagittal diameter. 68. Circumference of the Femur at Midshaft (Tape) The circumference measured at the midshaft at the same level of the sagittal and transverse diameters. Note that if the linea aspera is strongly accentuated at the midshaft and not across a larger part of the diaphysis, this measurement should be recorded approximately 10 mm above the midshaft. 69. Length of the Tibia. (OB) The distance from the superior articular surface of the lateral condyle of the tibia to the tip of the medial malleolus. 70. Maximum Epiphyseal Breadth of the Proximal Tibia. (OB) The maximum distance between the two most laterally projecting points on the medial and lateral condyles of the proximal epiphysis. 71. Maximum Epiphyseal Breadth of the Distal Tibia. (OB) The distance between

143

the most medial point on the medial malleolus and the lateral surface of the distal epiphysis. 72. Maximum Diameter of the Tibia at the Nutrient Foramen. (SL) The distance between the anterior crest and the posterior surface at the level of the nutrient foramen. 73. Transverse Diameter of the Tibia at the Nutrient Foramen. (SL) The straight line distance of the medial margin from the interosseous crest. 74. Circumference of the Tibia at the Nutrient Foramen. (Tape) The circumference measured at the level of the nutrient foramen. 75. Maximum Length of the Fibula. (OB) The maximum distance between the most superior point on the fibular head and the most inferior point on the lateral malleolus. 76. Maximum Diameter of the Fibula at Midshaft. (OB & SL) Find the midpoint on the osteometric board. Place the diaphysis of the fibula between the two anTIS of the caliper while turning the bone to obtain the maximum diameter. 77. Maximum Length of the Calcaneus. (SL) The distance between the most posterior projecting point on the tuberosity and the most anterior point on the superior margin of the articular facet for the cuboid measured in the sagittal plane and projected onto the underlying surface. 78. Middle Breadth of the Calcaneus (SL) The distance between the most laterally projecting point on the dorsal articular facet and the most medial point on the sustentaculum tali.

Exercise 9.3: Using the infracranial skeleton assigned by your instructor, provide each of the measurements described above. Exercise 9.4: Using the measurements taken in Exercise 9.3, calculate the required indices listed for this exercise. Note that the formula for each index uses the above numbers for each measurement.

144

Human Skeletal Anatomy

C . LABORATORY RESEARCH REPORT

Describe the skull you measured using the indices calculated in Exercise 9.2. Be sure to justify your characterization and interpretation of the indices (e.g., Bass, 1987).

Osteometries

145

Figure 9.1: Right lateral view of a skull demonstrating cranial landmarks (osteometric points).

146

Human Skeletal Anatomy

Figure 9.2: Anterior view of a skull demonstrating cranial landmarks (osteometric points).

Osteometries

Figure 9.3: Inferior (basal) view of a skull demonstrating cranial landmarks (osteometric points).

147

148

Human Skeletal Anatomy

Figure 9.4: Right lateral view of a mandible demonstrating mandibular landmarks (osteometric points).

Osteometries

Exercise 9.1

149

150

Human Skeletal Anatomy

,Osteometries

Exercise 9.2

151

152

Human Skeletal Anatomy

Exercise 9.3

Osteometries

153

154

Human Skeletal Anatomy

155

Answer Key

Answer Key Exercise 1.1 1. Axial and Flat 2. Appendicular and 3. Appendicular and 4. Axial and Flat 5. Appendicular and 6. Appendicular and

Long Long irregular or flat Short

Exercise 1.2a Cranium 1. Frontal 2. Parietal 3. Parietal 4. Temporal 5. Temporal 6. Occipital 7. Sphenoid 8. Ethmoid Face 1. Nasal 2. Nasal 3. Vomer 4. Maxilla 5. Maxilla 6. Zygomatic 7. Zygomatic 8. Lacrimal 9. Lacrimal 10. Mandible 11. Inferior Nasal Concha 12. Inferior Nasal Concha 13. Palatine 14. Palatine Ear Ossicles 1. Incus 2. Incus 3. Malleus 4. Malleus 5. Stapes 6. Stapes

Spinal Column 1. Cervical Vertebrae 2. Thoracic Vertebrae 3. Lumbar Vertebrae 4. Sacrum 5. Coccyx Sternum 1. Manubrium 2. Body 3. Xiphoid Process Ribs 1. Twelve Left 2. Twelve Right Exercise 1.2b Upper Extremities Shoulder Girdle 1. Clavicle 2. Clavicle 3. Scapula 4. Scapula Arms 1. Humerus 2. Humerus 3. Radius 4. Radius 5. Ulna 6. Ulna Hands 1. Carpals 2. Metacarpals 3. Phalanges Lower Extremities Pelvic Girdle 1. Os coxa 2. Os coax Legs 1. Femur 2. Femur 3. Patella 4. Patella 5. Tibia 6. Tibia 7. Fibula

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Human Skeletal Anatomy

8. Fibula Feet 1. Tarsals 2. Metatarsals 3. Phalanges

Exercise 1.5 1. Epiphysis 2. Cancellous Bone 3. Medullary Cavity 4. Compact Bone/Diaphysis 5. Epiphyseal Growth Plate Exercise 1.7 1. b 2. c 3. d 4. a 5. c Definitions 1. A bone that develops in a tendon or ligament 2. A small bone formed within a skull suture due to the suture switching back upon itself Exercise 2.1 1. Clavicular Notch 2. Manubrium 3. Lateral Facet for Rib 1 4. Sternal Angle 5. Body of Sternum 6. Full Facet for Rib 7. Xiphoid Process Articulations a. Body of Sternum, Right and Left Clavicles, Right and Left Rib 1, Right and Left Rib 2. b. Manubrium, Right and Left Ribs 2-7, Xiphoid Process. c. Body of Sternum Exercise 2.2 1. Shaft/Body of Rib

2. 3. 4. 5. 6.

Articular Facet of Head Neck Facet on Tubercle Costal Groove Articular/Costal Facet

Articulations a. Tl, Manubrium. b. T6, 17, Body of Sternum c. TID, Sternal Body via Costal Cartilage d. T12 Exercise 2.3 1. Greater Cornu 2. Body of Hyoid 3. Lesser Cornu Fill-in 1. Three 2. Sternal Angle 3. Vertebrochondral 4. One 5. Greater Cornua 6. Floating 7. Xiphoid Process 8. Scalene 9. Hyoid 10. Second Exercise 3.1 1. Full Facet for Head of Rib 2. Pedicle 3. Superior Articular process 4. Superior Articular Facet 5. Facet for Tubercle of Rib 6. Transverse Process 7. Lamina 8. Spinous Process 9. Inferior Vertebral Notch 10. Vertebral Body Exercise 3.2a 1. Vertebral Foramen 2. Anterior Tubercle 3. Facet for Occipital Condyle 4. Transverse Process

157

Answer Key

5. 6. 7. 8.

Posterior Arch Posterior Tubercle Transverse Foramen Anterior Arch

Exercise 3.2b 1. Odontoid Process/Dens 2. Superior Articular Facet 3. Vertebral Body 4. Transverse Process Exercise 3.3 Tl: Upper Full Facet, Lower Demi-Facet for Ribs. Articulates with Right and Left Rib 1, Right and Left Rib 2, C7, T2. T9: Upper Demi-Facet for Ribs. Articulates with Right and Left Rib 9, T8, TIO. TIO:Upper Full Facet for Ribs. Articulates with right and Left Rib 10, T9, TIl. Tl1:Upper Full Facet for Ribs. Articulates with Right and Left Rib 11, TIO, TI2. TI2:Upper Full Facet for Ribs. Articulates with Right and Left Rib 12, TIl, LI Exercise 3.4 1. Vertebral Body 2. Pedicle 3. Superior Articular Process 4. Transverse Process 5. Spinous Process 6. Inferior Articular Process 7. Inferior Articular Facet 8. Inferior Vertebral Notch Exercise 3.5a 1. Promontory 2. Ala 3. Transverse Line 4. Intervertebral Foramen 5. Third Vertebral Segment 6. Apex

Exercise 3.5b 1. Superior Articular Process 2. Ala 3. Median Sacral Crest 4. Lateral Sacral Crest 5. Sacral Cornu (hom) 6. Apex 7. Sacral Hiatus 8. Intervertebral Foramen 9. Intermediate Sacral Crest 10. Vertebral Canal Exercise 4.1 1. Sternal End 2. Sternal Facet 3. Nutrient Foramen 4. Groove for Subclavius Muscle 5. Shaft 6. Acromial Facet 7. Acromial End 8. Conoid Tubercle Articulations Clavicular Notch of Manubrium, Acromion Process of Scapula. Exercise 4.2a 1. Superior Border 2. Acromion Process 3. Glenoid Fossa 4. Groove for Circumflex Scapular Vessesls 5. Lateral/Axial Border 6. Inferior Angle 7. Medial/Vertebral Border 8. Infraspinatous Fossa 9. Spine 10. Superior Angle Articulations Acromial End of Clavicle, Head of Humerus Exercise 4.2b 1. Coracoid Process 2. Suprascapular Notch 3. Subscapular Fossa

158

Human Skeletal Anatomy

4. Lateral Lines 5. Groove for Subscapularis Muscle 6. Infraglenoid Tubercle Exercise 4.3a 1. Humeral Head 2. Anatomical Neck 3. Greater Tubercle 4. Intertubercular Groove 5. Crest of Greater Tubercle 6. Deltoid Tuberosity 7. Surgical Neck 8. Lesser Tubercle Exercise 4.3b 1. Lateral Supracondylar Ridge 2. Radial Fossa 3. Lateral Epicondyle 4. Capitulum 5. Trochlea 6. Trochlear Ridge 7. Medial Epicondyle 8. Coronoid Fossa 9. Medial Supracondylar Ridge Exercise 4.3c 1. Medial Supracondylar Ridge 2. Medial Epicondyle 3. Trochlear Ridge 4. Olecranon Fossa 5. Lateral Epicondyle 6. Lateral Supracondylar Ridge Articulations Glenoid Fossa of Scapula, Radial head, Trochlear Notch of Ulna. Exercise 4.4a 1. Radial Head 2. Articular Circumference 3. Neck 4. Radial Tuberosity 5. Anterior Oblique Line 6. Interosseous Border

Exercise 4.4b 1. Styloid Process 2. Distal Articular Surface 3. Ulnar Notch Exercise 4.4c 1. Dorsal Tubercle 2. Styloid Process Articulations Capitulum of Humerus, Radial Notch of Ulna, Radial Articulation on Head of Ulna, Scaphoid, Lunate. Exercise 4.5a 1. Olecranon Process 2. Trochlear Notch 3. Coronoid Process 4. Radial Notch 5. Ulnar Tuberosity 6. Supinator Crest 7. Interosseous Border Exercise 4.5b 1 .Interosseous Border 2. Ulnar Head 3. Radial Articulation 4. Styloid Process Articulations Trochlea of Humerus, Head of Radius, Ulnar Notch of Radius. Exercise 4.6a 1. Distal Phalanx of First Digit 2. Proximal Phalanx of First Digit 3. Metacarpal I 4. Trapezium 5. Scaphoid 6. Lunate 7. Triquetral 8. Hamate 9. Capitate 10. Trapezoid

Answer Key

159

Exercise 4.6b I.Pisiform 2.Metacarpal V 3.Metacarpal IV 4.Metacarpal III 5.Metacarpal II 6.Middle Phalanx Second Digit

Exercise 5.2a 1. Head of Femur 2. Fovea Capitis 3. Neck of Femur 4. Intertrochanteric Line 5. Diaphysis/Shaft 6. Greater Trochanter

Exercise 5.1a 1. Iliac Crest 2. Anterior Superior lliac Spine 3. Anterior Inferior Iliac Spine 4. Lunate Surface 5. Acetabulum 6. Pubic Tubercle 7. Pubis 8. Ischium 9. Ischial Tuberosity 10. Less Sciatic Notch 11. Greater Sciatic Notch 12. Posterior Inferior Iliac Spine 13. Posterior Superior lliac Spine 14. Posterior Gluteal Line 15. Inferior Gluteal Line 16. Ilium 17. Anterior Gluteal Line

Exercise 5.2b 1. Fovea Capitis 2. Head of Femur 3. Lesser Trochanter 4. Spiral Line

Exercise 5.1b 1. Iliac Tuberosity 2. Auricular Surface 3. Preauricular Sulcus 4. Ischial Spine 5. Inferior Pubic Ramus 6. Pubic Symphysis 7. Obturator Foramen 8. Superior Pubic Ramus 9. Iliopubic Eminence 10. Arcuate Line 11. Ilium Articulations Right and Left Ox Coxa (with one another at Pubic Symphysis), Femur, Sacrum.

Exercise 5.2c 1. Greater Trochanter 2. Intertrochanteric Crest 3. Lesser Trochanter 4. Gluteal Tuberosity 5. Nutrient Foramen 6. Linea Aspera Exercise 5.2d 1. Adductor Tubercle 2. Medial Epicondyle 3. Patellar Surface 4. Lateral Epicondyle Exercise 5.2e 1. Lateral Epicondyle 2. Lateral Condyle 3. Intercondylar Fossa 4. Medial Condyle 5. Adductor Tubercle 6. Supracondylar Lines Articulations as Coxa, Patella, Tibia. Exercise 5.3a 1. Base 2. Apex 3. Notch for Vastus Lateralis

160

Exercise 5.3b 1. Notch for Vastus Lateralis 2. Lateral Facet 3. Apex 4. Medial Facet Exercise 5.4a 1. Medial and Lateral Intercondylar Eminences 2. Tibial Tuberosity 3. Anterior Border Exercise 5.4b 1. Medial and Lateral Intercondylar Eminences 2. Lateral Condyle 3. Proximal Fibular Facet 4. Interosseous Border 5. Nutrient Foramen 6. Soleal Line 7. Posterior Intercondylar Area 8. Medial Condyle Exercise 5.4c 1. Interosseous Border 2. Fibular Notch 3. Groove for Tibialis Tendon 4. Medial Malleolus Articulations Femur, Fibula, Talus Exercise 5.5a 1. Apex of Head 2. Tibial Facet 3. Interosseous Border Exercise 5.5b 1. Apex 2. Head 3. Interosseous Border Exercise 5.5c 1. Articular Surface for Talus 2. Malleolar Fossa

Human Skeletal Anatomy

Exercise 5.5d 1. Lateral Malleolus Articulations Tibia, Talus Exercise 5.6a 1. Middle Phalanx of Digit II 2. Distal Phalanx of Digit I 3. Proximal Phalanx of Digit I 4. Metatarsal I 5. Metatarsal IT 6. Metatarsal ITI 7. Metatarsal IV 8. Metatarsal V 9. Cuboid 10. Lateral Cuneiform 11. Intermediate Cuneiform 12. Medial Cuneiform 13. Navicular 14. Talus Neck 15. Trochlear Surface of Talus 16. Calcaneus 17. Calcaneal Tuberosity 18. Lateral Articular Surface of Talus Exercise 5.6b 1. Middle Phalanx of Digit lIT 2. Distal Phalanx of Digit IV 3. Proximal Phalanx of Digit II 4. Metatarsal I 5. Metatarsal IT 6. Metatarsal ITI 7. Metatarsal IV 8. Metatarsal V 9. Medial Cuneiform 10. Intermediate Cuneiform 11. Lateral Cuneiform 12. Cuboid 13. Navicular 14. Head of Talus 15. Sustentaculum Tali 16. Medial Posterior Tubercle 17. Calcaneal Tuberosity 18. Calcaneus

Answer Key

Exercise 6.1 Articulations Frontal: Left and Right Parietals, Left and Right Nasals, Left and Right Lacrimals, Sphenoid, Ethmoid, Left and Right Zygomatics, Left and Right Maxillae Parietal: Frontal, Sphenoid, Temporal, Occipital Occipital: Left and Right Parietals, Left and Right Temporals, Sphenoid, Atlas (C1) Temporal: Sphenoid, Zygomatic, Parietal, Occipital, and Mandible Sphenoid: Frontal, Left and Right Parietals, Left and Right Temporals, Occipital, Ethmoid, Vomer, Left and Right Palatines, Left and Right Zygomatic Ethmoid: Frontal, Left and Right Lacrimals, Vomer, Sphenoid, Left and Right Nasals, Left and Right Maxilla, Left and Right Palatines, Left and Right Inferior Nasal Conchae Nasal: Frontal, Maxilla, Ethmoid, Opposite Nasal Maxillary: Opposite Maxilla, Frontal, Nasal, Vomer, Ethmoid, Inferior Nasal Conchae, Zygomatic, Lacrimal, Sphenoid, Palatine Lacrimal: Frontal, Maxilla, Ethmoid, Inferior Nasal Concha Zygomatic: Frontal, Sphenoid, Maxilla, Temporal Mandible: Left and Right Temporals Vomer: Ethmoid, Left and Right Maxillae, Left and Right Palatines, Sphenoid Inferior Nasal Concha: Maxilla, Ethmoid, Lacrimal, Palatine Palatine: Sphenoid, Ethmoid, Maxilla, Inferior Nasal Conchae, Vomer, Opposite Palatine

Exercise 6.2/3a Calvarial Elements and Features 1. Superior Temporal Line 2. Coronal Suture

161

3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.

Temporal Line Region of Temporal Fossa Zygomatic Process of Frontal Greater Wing of Sphenoid Zygomatic Process of Temporal External Auditory Meatus Mastoid Process Superior Nuchal Line Squamous Portion of Temporal Supramastoid Crest Lambdoid Suture Parietal Notch Squamosal Suture Parietal Eminence

Facial Elements and Features 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32.

NasalBone Frontal Process of Zygomatic Posterior Lacrimal Crest Anterior Lacrimal Crest Lacrimal Bone Anterior Nasal Spine Maxilla Alveolus Mental Foramen Mental Eminence Body Gonial Angle Ascending Ramus Articular Condyle Coronoid Process Temporal Process of Zygomatic

Exercise 6.2/3b Calvarial Elements and Features 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

Frontal Frontal Eminence Supraorbital Margin Superciliary Arch Superior Orbital Fissure Sphenoid (Greater Wing) Inferior Orbital Fissure Zygomatic Process of Frontal Supraorbital Foramen Supraorbital Notch

162

Facial Elements and Features 11. Infraorbital Margin 12. Infraorbital Foramen 13. Inferior Nasal Concha 14. Mental Eminence 15. Mental Foramen 16. Alveolus of Maxilla 17. Nasal Aperture 18. Zygomatic Process of Maxilla 19. Zygomaticomaxillary Suture 20. Zygomatic (or Zygomatico-orbital Foramen) 21. Perpendicular Plate of Ethmoid 22. Frontal Process of Maxilla 23. Nasal Bone Exercise 6.2/3c Calvarial Elements and Features 1. Greater Wing of Sphenoid 2. Pterygoid Process 3. Foramen Ovale 4. Foramen Spinosum 5. Carotid Foramen 6. Jugular Fossa 7. Jugular Foramen 8. Occipital Condyle 9. Extennal Occipital Protuberance 10. Inferior Nuchal line 11. Foramen Magnum 12. Posterior Condylar Canal 13. Jugular Process 14. Mastoid Groove 15. Mastoid Process 16. Ecto-tympanic Plate 17. Mandibular Fossa 18. Articular Tubercle 19. Lateral Pterygoid Plate 20. Pterygoid Fossa 21. Medial Pterygoid Plate 22. Pharyngeal Tubercle 23. Foramen Lacerum Facial Elements and Features 24. Ala of Vomer 25. Spheno-palatine Foramen

Human Skeletal Anatomy

26. 27. 28. 29.

Horizontal Plate of Palatine Palatal Process of Maxilla Incisive Foramen Zygomatic Arch

Exercise 6.2d 1. Parietal 2. Sagittal Suture 3. Superior Temporal Line 4. External Occipital Protuberance 5. Superior Nuchal Line 6. Mastoid Process 7. Occipital 8. Lambdoid Suture 9. Lambda Exercise 6.2e 1. Frontal 2. Coronal Suture 3. Sagittal Suture 4. Superior Temporal Line 5. Right Parietal 6. Left Parietal Exercise 6.2f 1. Frontal Crest 2. Foramen Cecum 3. Orbital Plate 4. Crista Galli 5. Cribriform Plate 6. Lesser Wing of Sphenoid 7. Jugum 8. Chiasmatic Groove 9. Optic Foramen 10. Hypophyseal Fossa 11. Anterior Clinoid Process 12. Foramen Ovale 13. Foramen Spinosum 14. Petrous Portion of Temporal 15. Posterior Clinoid Process 16. Clivus 17. Foramen Lacerum 18. Sigmoid Sinus 19. Foramen Magnum

Answer Key

20. 21. 22. 23.

Hypoglossal Canal Transverse Sinus Internal Occipital Crest Internal Occipital Protuberance

Exercise 6.2g 1. Frontal 2. Coronal Suture 3. Anterior Meningeal Artery Impressions 4. Granular Foveolae/Arachnoid Granulations 5. Left Parietal 6. Sagittal Suture 7. Sagittal Sinus 8. Right Parietal

163

Exercise 6.2h 1. Optic Chiasma 2. Jugum 3. Middle Clinoid Process 4. Posterior Clinoid Process 5. Dorsum Sellae 6. Optic Foramen 7. Foramen Ovale 8. Anterior Clinoid Process 9. Foramen Rotundum 10. Greater Wing of Sphenoid 11. Lesser Wing of Sphenoid 12. Hypophyseal Fossa

Exercise: 7.1

Exercise: 7.5

164

Exercise 7.6 1. Enamel 2. Dentine 3. Crown 4. Root 5. Root Apex 6. Apical Foramen 7. Cementum 8. Pulp Chamber 9. Cementoenamel Junction (eEJ)

Human Skeletal Anatomy

References

References Anderson (1962) The Human Skeleton: A Manual for Archaeologists. Ottawa: Department of Northern Affairs and National Resources. Bass WM (1987) Human Osteology: A Laboratory and Field Manual. (Third Edition). Columbia, Missouri: Missouri Archaeological Society. Brooks ST and Suchey JM (1990) Skeletal Age Determination Based on the Os Pubis: A Comparison of the Acsadi-Nerneskeri and Suchey-Brooks Methods. Human Evolution. 5: 227-238. Brothwell DR (1965) Digging Up Bones. London: Trustees of the British Museum of Natural History. Buikstra JE and Ubelaker DH (eds.) (1994) Standards for Data Collection from Human Skeletal Remains. Arkansas Archeological Survey Research Series No. 44. EI-Najjar MY and McWilliams KR (1978) Forensic Anthropology: The Structure, Morphology, and Variation of Human Bone and Dentition. Springfield, lllinois: Charles CThomas. Fairgrieve SI and Bashford J (1987) A Radiographic Technique of Interest to Physical Anthropologists. American Journal ofPhysical Anthropology. 77(1): 23-26. Isc an MY and Loth SR (1986) Determination of Age from the Sternal Rib in White Females: A Test of the Phase Method. Journal of Forensic Sciences. 31: 990-999.

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Iscan MY, Loth SR, and Wright RK (1984) Age Estimation from the Rib by Phase Analysis: White Males. Journal of Forensic Sciences. 29: 1094-1104. Iscan MY, Loth SR, and Wright RK (1985) Age Estimation From the Rib by Phas Analysis: White Females. Journal of Forensic Sciences. 30: 853-863. Iscan MY, Loth SR, and Wright RK (1987) Racial Variation in the Sternal Extremity of the Rib and its Effect on Age Determination. Journal ofForensic Sciences. 32: 452-466. Masset (1989) Age Estimation on the Basis of Cranial Sutures. In: MY Iscan (ed.): Age Markers in the Human Skeleton. Springfield, Illinois: Charles C Thomas. pp. 71-103. Meindl RS and Lovejoy CO (1985) Ectocranial Suture Closure: A Revised Method for the Determination of Skeletal Age at Death Based on the Lateral-Anterior Sutures. American Journal of Physical Anthropology. 68: 57-66. Molto JE (1983) Biological Relationships of Southern Woodland Peoples: The Evidence of Discontinuous Cranial Morphology. Ott~wa: National Museum of Man Mercury Senes, Archaeological Survey of Canada, PaperNo. 117. Moore-Jansen PM, Ousley SO, and Jantz RL (1994) Data Collection Procedures for Forensic Skeletal Material. Report of Investigations No. 48. Knoxville: Department of Anthropology, The University of Tennessee.

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Moorrees CFA, Fanning EA, and Hunt EE (1963a) Formation and Resorption of Three Deciduous Teeth in Children. American Journal of Physical Anthropology. 21: 205213. Moorrees CFA, Fanning EA, and Hunt EE (1963b) Age Variation of Formation Stages for Ten Permanent Teeth. Journal of Dental Research. 42 (6): 1490-1502. Ortner DJ and Putschar WGJ (1985) Identification of Pathological Conditions in Human Skeletal Remains. Smithsonian Contributions to Anthropology. Number 28. Washington: Smithsonian Institution Press. Phenice TW (1969) A Newly Developed Visual Method of Sexing the Os Pubis. American Journal of Physical Anthropology. 30: 297-301. Schwartz JH (1995) Skeleton Keys. New York: Oxford University Press. Steele DG and Bramblett CA (1988) The Anatomy and Biology of the Human Skeleton. College Station, Texas: Texas A&M University Press. Taylor RMS (1978) Variation in Morphology of Teeth and Forensic Aspects. Springfield, Illinois: Charles C Thomas. Ubelaker DH (1984) Positive Identification from the Radiographic Comparison of Frontal Sinus Patterns. In: T Rathbun and J Buikstra (eds.): Human Identification: Case Studies in Forensic Anthropology. Springfield, Illinois: Charles C Thomas. pp. 399-411.

White TD and Folkens PA (2000) Human Osteology. (Second Edition). New York: Academic Press.