University of Tennessee, Knoxville Trace: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 5-2005 Serial Long Bone Histology: Inter- and Intra-Bone Age Estimation Mariateresa Anne Tersigni University of Tennessee - Knoxville Recommended Citation Tersigni, Mariateresa Anne, "Serial Long Bone Histology: Inter- and Intra-Bone Age Estimation. " PhD diss., University of Tennessee, 2005. http://trace.tennessee.edu/utk_graddiss/2298 This Dissertation is brought to you for free and open access by the Graduate School at Trace: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of Trace: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Mariateresa Anne Tersigni entitled "Serial Long Bone Histology: Inter- and Intra-Bone Age Estimation." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in Anthropology. Murray K. Marks, Major Professor We have read this dissertation and recommend its acceptance: William M. Bass, Walter E, Klippel, Darinka Mileusnic Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official student records.) To the Graduate Council: I am submitting herewith a dissertation written by Mariateresa Anne Tersigni entitled “Serial Long Bone Histology: Inter- and Intra-Bone Age Estimation.” I have examined the final electronic copy of this dissertation for form and content and recommended that it be accepted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in Anthropology. _Murray K. Marks____________ Major Professor We have read this dissertation and recommend its acceptance: _William M. Bass______________ _Walter E, Klippel_____________ __Darinka Mileusnic___________ Accepted for the Council: _____Anne Mayhew_______________ Vice Chancellor and Dean of Graduate Studies (Original signatures are on file with official student records.) SERIAL LONG BONE HISTOLOGY: INTER- AND INTRA- BONE AGE ESTIMATION A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Mariateresa Anne Tersigni May 2005 Dedication This dissertation is dedicated to my grandmother, Benedetta Tersigni, whose passing was a shock to all of us. Her love of life and undying devotion to family is the legacy that she leaves for us. May her spirit live on in each of us. Thank you Grandma Betta for all that you have taught me, thank you for your wise words and most of all thank you for listening without judgment and for praying for me no matter how impossible my dreams seemed. I am glad you were able to be at my defense after all. I love you and will miss you immensely. I would like to dedicate this culmination of my collegiate career to my parents: Dr. Anthony R. Tersigni and Mrs. Flora P. Tersigni. How do I begin to express my deep gratitude and undying love for these two people who have supported me throughout my success and trials over this nine year journey and over the past 26 years of my life? By your example, you have each taught me how to work hard and that I can accomplish anything that I set my mind to. Thank you for allowing me the freedom to choose my own road, no matter how scared you were for me. I did it, Mom and Dad! I am finally Dr. Mariateresa Anne Tersigni, as I always told you I would be. I love you both and cannot thank you enough for your support. This work is also dedicated to my academic “Dads”, Dr. Norman J. Sauer and Dr. Murray K. Marks. The two of you have seen me through this past nine years and pushed me to achieve my goals. Even through my stubbornness and tears you helped me to strive for the impossible. You knew what was best for me, and you made sure that I took that road no matter how hard I kicked and screamed along the way. Your support in both the academic arena as well as the emotional realm has been the source of strength and courage for me through even my toughest times. Thank you for never giving up on me and for believing that I had great things in store for my future. Thank you for helping me realize my academic dream and by your example, strengthen my passion for teaching and research. I am lucky to have been your student and honoured to call you both friends. I love you both and I blame this whole mess on both of you. I could NEVER have done it without you! ii Acknowledgements I would like to begin by thanking Dr. Norman J. Sauer. It seems so long ago I wrote you a letter asking to help you in your lab. I was so scared to talk with you, so afraid to approach “THE” Dr. Norman J. Sauer. You allowed me into your lab and brought me into the world of Physical Anthropology. And for that I am immensely grateful! I will never be able to repay you for your continued support and superior wisdom, but I will never stop trying to find a way to give you even half of what you have given me. I would like to thank the members of my dissertation committee who have helped me down this winding road: Dr. Murray Marks, my friend and co-chair. Thank you for all of your help during this research and for being my biggest supporter even when others thought this research was useless. You saw the opportunity and just did it. Thanks for instilling your spirit within me. Thank you for every opportunity you have afforded me and thank you for always making me work hard for those opportunities…you and I both know it somehow means a lot more when you have to work your butt off to do it, not matter how little everyone else has to do for a similar opportunity. Thanks for believing in me through it all and for forcing me not to abandon my dreams. Nobody can EVER take this away from me…THIS IS MINE! Mostly thanks for being one of the best friends that I have. Dr. W. Emerson Klippel, my other co-chair, and the protector of my sanity. Each day as I passed you in the hall I was greeted with a warm smile and treated to a joyful laugh. I will never forget that day in your office before my prelims, when I cried my eyes out and wanted to quit and you wouldn’t let me. Your constant support and ne’er a cross iii word has helped me through this struggle. Your enthusiasm for each of my crazy ideas and your willingness to help, even when it required plumbing and electrical work will never be forgotten. You are truly the kindest man I know. I will forever b in your debt. Dr. William M. Bass, the one who started it all. Your steadfast excitement about my research and your devotion to the advancement of this field has been one of the beacons of light through this ordeal. You are one of the pillars of this Anthropology department and I appreciate your willingness to allow me to learn from you both in the classroom and in the lab. Dr. Darinka Mileusnic: Thank you for your care and concern both in the academic arena and outside of it. You have taught me so much about forensic pathology, departmental politics and life in general.. I will miss our Saturday morning conversations over an autopsy or two. Thank you for agreeing to help me with this process and thanks so much for glowing smile each time I come to see you. You have helped me in more ways than you realize. Dr. Douglas H. Ubelaker, the man behind the scenes. Thank you for the immesurable amount of time you spent responding to my emails and allowing me to visit you at the Smithsonian with my countless questions. I appreciate your insight and especially your fervent support of this project. Thank you for helping me to narrow my focus into something manageable for ONE dissertation. Your kindness and encouragement has been evident since my first presentation at AAFS 2001. iv The people behind the scenes: I would like to thank all of my friends who have helped me throughout this long and winding road. You constant support and willingness to give of yourself in my times of need has helped me become what I am today. Each and every one of you have helped me in ways I cannot express. I would like to take this opportunity to specifically thank a few of those friends who have been the backbone of my support system. Natalie Langley: Thank you for your forgiveness and your willingess to give me a second chance. I will never forget your openness and honesty. You are definitely one of the best things about my time in Knoxville. I truly value our friendship and I am looking forward to a lifetime of academic collaboration, close friendship and of course the occasional wardrobe critique. And to George, thank you for always treating me like a princess and for introducing me to Grainger County, it brings peace to my soul every time I visit. Thank you for welcoming me into your world. You’re kindness will never be forgotten. I heard that! Derinna Kopp and Andrea Rombauer: You have each helped me get through the past five years. I cannot begin to tell you how much I appreciate each of you. You are very special to me. Franklin Damann (Foxtrot Echo Delta): Fronkers, thanks for your support and for your friendship. Your kindness has been overwhelming. I wish you and Laurel the best of luck and hope that your love burns eternally for one another. Dr. Derek “Monkeyboy” Benedix: Brother, where do I start? If you iddn’t come into my life I am not sure I could’ve made it through the last few years. You came back to Knoxville to write your dissertation at exactly the right time. You have always been v there for me whenever I need you even when I am freaking out on a Sunday at 6am your time. I love you ,friend, more than you may ever know and I count my self very lucky ot have you as my good friend. Dr. Michelle “Miiiiiisssseeeeerrrryyyyyy” Hamilton: Grazie per la compartecipazione della vostra saggezza di come sopravvivere in questo reparto con me. Thanks for enthusiasm and for introducing me to Strindberg and 909 and so much more. Ti amo! Heather Brewer: Brew, thanks for being a part of my life. I am so glad that I met you in Italy and I am so glad that we trusted each other enough to become good friends. I love you so much. Please remember: You will never find happiness with anyone else unless you first find it within yourself. You are strong and beautiful on your own; you don’t need anyone to be who you are inside. Juliet Brophy: Jules- thanks for your friendship and love. Thank you for sharing beers and tears with me. Thanks for always being there for me and for making sure I never doubt myself. You are an amazing woman and a true friend. I hope you will always believe that and understand that YOU are truly a prize! Love ya, babe. T. James Smith: James, you and I are so much alike it is scary. Your friendship and compassion has gotten me through this dissertation. Thanks for our sushi dates and our Sunspot chat sessions. All I want is for you to find your happiness, and I hope that you are on your road to that end. Thank you for understanding me no matter how hard i try to hide my feelings. I am grateful our paths crossed in this life and I hope our friendship continues throughout our lives. I love you. vi Lindsey Caldwell- Oh my dearest Ariel! You are the best girlfriend I have on this earth. Who would have thought that we would have shared so many stories, tears, smiles and adventures? I am so proud of the woman you are ( and that’s the gospel truth!) and I know that you will continue to make me proud as you move toward achieving your goals. Your friendship and unconditional love has helped me through so much. I’m just throwing that out there do what you want with it! I appreciate your compassion and concern and I know that we will be best friends until we are old ladies together. I can’t wait to laugh about these years and how crazy we were from karaoke to 80’s night at Michael’s and all the other crazy experiences we have shared. Sorry Lord, we didn’t mean it. I got a fever and the only prescription is Caldwell (or cowbell!) There’s your sign! I love you girl… eat your ‘tater salad! To Paco and Peanut: You have shown me that “SOUL MATES” do exist and that you never know where you will find them. I hope you eventually get that farm house with the white picket fence and the rocking chairs on the porch. I hope your attic is full of old handmade quilts and that your dock has a sailboat at the ready whenever you may wish to drift away from this world for a while. Thank Dr. Werner U. Spitz, for your unconditional support and for teaching more in one summer than I have learned in any university course. You have truly inspired me to pursue what I love. I will be forever indebted to you for sharing your expertise with me. I will never forget what you have taught me. I would like to thank brother and sister for their unconditional love and unwavering belief in me. Andrea, I am so glad that we have become so close throughout this journey. I am so lucky to have found in you one of my closest companions, my vii cheerleader and a lifelong friend. Thank you for understanding my decisions and for standing firmly beside me through all of this. Your consideration and enthusiasm has been a godsend. I love you! John, thanks for helping to keep me on this path. I will never forget our long discussions and countless tears. Your friendship has helped me through so much. Thank you for your loyalty and for making sure I know that I am not the smartest in the Tersigni family. I love you! Andrew, thanks for always sticking up for me and for taking such great care of my sister. You are a welcome addition to this family and I look forward to calling you “brother”. Jenny, thank you for giving me a shoulder to cry on during your time in Tennessee and thank you for treating me like your sister. Your kind words have brought me through some very difficult times and for that I am grateful. Mom: Thanks for the advice and for trying to understand what I am going through especially during this past 5 years. Thank you for allowing me the opportunity to make my own decisions and make my own mistakes. Thank you for listening and for your love and prayers. I love you more and more everyday! Dad, how can I begin to thank you? Your drive and determination to achieve your goals taught me how to succeed. I have learned what is important in life from watching you. I am so glad that you have allowed me to follow my dreams and my heart. Thank you for your emotional and financial support. Thank you , Dad, for the best Sunday I have ever had. That day with you in Arizona meant more than you know. I love you with all I have. To my grandparents, Andrea and Benedetta Tersigni and Mario and Maria Pelino: Thank you for your prayers and encouragement throughout my life. Your strong work ethic and dedication to the family has helped me become the woman I am today. Thank you for teaching me how to work hard and love deeply. Le amo! viii Thank you to all of my aunts, uncles and cousins, who are to numerous to mention by name. I appreciate your support and prayers over the past nine years. I love and appreciate you all very much. Thanks for always being interested in what I do. I am very lucky to call you my family. To Canis Familiaris Zinjanthropus (Zinj): You have been my one rock and my one constant through all of this. Your kisses and playful nature help me realize what is actually important in this world. You have taught me what unconditional love is all about. I love you Brother Bear! Thank you to Brandon L. Raile: How do I begin to thank you for your friendship and your patience? Your love and support came at exactly the right time. Your calm and gentle manner has brought me out of many a tizzie and your willingness to help (especially with computer issues) has been overwhelming. Thank you for getting me over my fear of photoshop, and thanks for being there as the rest of my fears slowly melt away. Your patience and devotion is evident in everything you do. Thank you from the bottom of my heart. I love you…Remember Sailor, Love Endures. Finally, to Muzza: I cannot find the words to express what you mean to me. You have brought me out of the abyss and have saved me from myself far too many times to count. You have shown me what it is to be a true friend, no matter what obstacles stand in the way. Thank you for being there academically and emotionally throughout this very rough road. Thanks for making sure I never gave up on this dream or myself. I hope that you know I will be there whenever you need me, no matter what, SAVVY?! You mean the world to me and I don’t know what I would do without you in my life. You have helped me to make a friend in knowledge and you have shown me that she will never ix leave me no matter how many of my other friends do. You have taught me so much, including that knowledge will always provide me a safe harbor and for this I am in your debt for eternity. I can only reminisce with some things that that have brought a smile to my face even on the darkest of days: F and S, dearest Muzza, F and S! “Black as is my need, bleeding as is my heart! The agony is intolerable… For You!” It is either genius or madness…amazing how often the line between the two is blurred. It’s no good friend, no good! I’m little! I don’t have any shoes on. Muzza, just know that when I find the world cold, I will crawl under the patchwork and feel the needle’s binding. Thanks for giving me something to find comfort and solace in for the rest of my life, you have no idea how the mere idea of a quilt comforts me. Thanks for sharing your faded dreams, so that my dreams may shine brightly! x Abstract Few publications report on histological differentiation within and between mammalian long bone cortices. Specifically, are osteon populations unique to proximal, midshaft or distal segments? First, this study tests Kerley’s (1965) quantification categories, i.e., number of osteons, fragments, and non-Haversian canals and percent circumferential lamellae, to estimate age and second, quantifies those micro-structural differences within and between human femur, tibia and fibula based upon section location. In an identical attempt to understand within-bone differences, i.e., proximal from distal, the same Kerley criteria were qualified and quantified within and between humeral, radial and ulnar diaphyses. However, no age estimation via Kerley was made on the pectoral limb bones, as the method never intended to assess age using these. Using a Buehler Isomet 1000 saw, three thin sections were made from numerous one-centimeter segments cut from each entire diaphysis. Sections were quantified identical to Kerley’s quadrant (anterior, posterior, medical and lateral) using a Leica DMRX light microscope at 16, 50 and 100 magnifications. After video-image capture, morphometric analysis of utilized Image-Pro Express software with a Dell Optiplex GX270 computer. Quantification of these structures indicates statistically significant within-bone differences, i.e., throughout the shaft, which result in significantly different age estimations. The means for each quantification category were examined independently across the four fields using repeated measures ANOVA at the .05 level. Regression equations for age estimation using Kerley based on the femur, tibia and fibula reveal widely inconsistent age estimations when compared to those derived from midshaft. xi Those findings generate two related conclusions: Metabolically and/or mechanically, bone maintenance and remodeling varies greatly within the shaft. Second, fragment location must be identified and existing Kerley and Ubelaker (1978) equations be used only for midshaft. As this research demonstrates, moving proximal or distal from midshaft will result in spurious age estimation particularly pertinent to fragmentary remains. Furthermore, this research underscores that fact that ageing methods developed from fragmentary bone must account for significant difference of microstructural populations throughout the shaft as well as within one thin section. xii Table of Contents Section Page Chapter 1: Introduction 1 Chapter 2: Bone Biology, Embryology and Histology Embryonic Development of Bone Bone Maintenance Cells Bone Formation and Maintenance Bone Mineral Composition Types of Human Bone Mature Bone 6 6 10 13 19 19 21 Chapter 3: Anthropological Uses of Bone Histology 26 Bioarchaeological and Paleopathological Uses of Bone Histology 33 The Future of Bone Histology in Anthropology 37 Chapter 4: Materials and Methods 38 Chapter 5: Results 49 Chapter 6: Discussion 77 Chapter 7: Conclusions 84 References Cited 87 Appendices 93 Appendix A: Osteometric Measurements of Individuals A, B and C 94 Appendix B: Raw Data for Kerley’s Four Quantification Categories 96 Vita 104 xiii List of Tables Table 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. Page Factorial ANOVA summary for femur A Post Hoc Summary for Percent Non-Haversian Bone Repeated Measures ANOVA Summary for Osteon Count Repeated Measures ANOVA Summary for Fragment Count Repeated Measures ANOVA Summary for Percent Non-Haversian Bone Differences of Least Square Means for Posterior Radius Differences of Least Square Means for Lateral Radius Differences of Least Square Means for Anterior Ulna Differences of Least Square Means for Lateral Femur (Osteon Count) Differences of Least Square Means for Lateral Tibia Differences of Least Square Means for Ulna (Fragment Count) Differences of Least Square Means for Fibula (Fragment Count) Differences of Least Square Means for Humerus (Percent Non-Haversian) Differences of Least Square Means for Ulna (Percent Non-Haversian) Differences of Least Square Means for Fibula (Percent Non-Haversian) xiv 70 70 72 73 73 73 74 74 74 75 75 75 76 76 76 List of Figures Figure 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. Page Human Haversian bone compared to deer plexiform bone Somite alignment along neural tube Zones of endochondral ossification Osteoclasts in Howship’s lacunae Osteoblasts laying down osteoid on bony trabecula Osteocytes Cement (reversal) line Fragmentary osteon associated with secondary osteons BMU tunneling through old bone Plywood lamellar architecture Human bone periosteum and endosteoum Compact and cancellous bone Schematic of human bone structure Microscopic view of Haversian bone Elements of each sample Scoring of the bones for sectioning Macroscopic cross sectional variation of the femur Buehler Isomet 1000 thin sectioning saw slicing a cross section of fibula Microscopic slide of sample A Features measured in the Kerley method of histological age estimation Capturing four microscopic fields Superimposition of 2.06mm2 field size on captured image Labeling of the microstructures within the field Raw Osteon Counts for Femur "A" Across Kerley's Four Fields Raw Fragment Counts for Femur "A" Across Kerley's Four Fields Percentage of Non-Lamellar Bone for Femur "A" Across Kerley's Four Fields Raw Osteon Counts for Femur "A" Across Medial and Lateral Fields Raw Fragment Number for Femur "A" Across Medial and Lateral Fields Percent Non-Haversian Bone for Femur "A" Across Medial and Lateral Fields Age Estimates (Osteons) for Femur (A) Age Estimates (Fragments) for Femur (A) Age Estimates (% Non-Haversian) for Femur (A) Age Estimates (Osteons) for Tibia (A) Age Estimates (Fragments) for Tibia (A) Age Estimates (% Non-Haversian) for Tibia (A) Age Estimates (Osteons) for Fibula (A) Age Estimates (Fragments) for Fibula (A) Age Estimates (% Non-Haversian) for Fibula (A) xv 2 7 9 11 12 12 15 16 17 20 21 22 23 23 39 40 42 43 43 44 44 46 46 50 50 51 51 52 52 54 54 55 55 56 56 57 57 58 List of Figures (Continued) Figure 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. Page Age Estimates (Osteons) for Femur (B) Age Estimates (Fragments) for Femur (B) Age Estimates (% Non-Haversian) for Femur (B) Age Estimates (Osteons) for Tibia (B) Age Estimates (Fragments) for Tibia (B) Age Estimates (% Non-Haversian) for Tibia (B) Age Estimates (Osteons) for Fibula (B) Age Estimates (Fragments) for Fibula (B) Age Estimates (% Non-Haversian) for Fibula (B) Age Estimates (Osteons) for Femur (C) Age Estimates (Fragments) for Femur (C) Age Estimates (% Non-Haversian) For Femur (C) Age Estimates (Osteons) for Tibia (C) Age Estimates (Fragments) for Tibia (C) Age Estimates (% Non-Haversian) for Tibia (C) Age Estimates (Osteons) for Fibula (C) Age Estimates (Fragments) for Fibula (C) Age Estimates (% Non-Haversian) for Fibula (C) Mean Age Predictions For Femur (A) Average Age Estimations (Individual A) Average Age Estimations (Individual B) Average Age Estimations (Individual C) xvi 58 59 59 60 60 61 61 62 62 63 63 64 64 65 65 66 66 67 67 68 68 69 Chapter 1: Introduction The frequency of fragmentary casework in forensic medicine is on the increase. Bone fragmentation, depending upon size and location within the skeleton, challenges the quintessential biological profile of age, sex, ancestry and stature, as the morphological traits routinely examined to make these estimations are missing. Most of the techniques that help to estimate the biological profile require mostly whole if not entire bones of the skeleton. Thus, fragmentary remains prove difficult to identify as human, not to mention estimating the biological age, sex, ancestry and stature from those fragments. Advances in microscopic techniques as well as an increased need for species identification has led to advances in the study of bone histology. Using bone thin sections, microscopy can aid in the determination of whether fragments are “human” or “non-human.” In 1956, researchers where diagnosing bone at the genus and species level based upon bone histomorphology (see Enlow and coworkers 1956a, b, c), i.e., differentiation between reptile, mammal, and fish. Within the class Mammalia, the histomorphological structure can be quite similar among genera. For example, sheep and goat have similar plexiform, or parallel layered bone. Some mammals do have distinct histomorphology; humans, for example, are one of the only species within Mammalia to have full Haversian (osteonal) bone from the periosteal (outer surface) to endosteal (inner surface), i.e., the full thickness of the cortical layer. Many dogs can have osteonal bone in the center of the cortical layer while still maintaining plexiform bone near the endeosteal and periosteal regions. Chimpanzees 1 also have full Haversian bone, though the osteon size and arrangement is quite distinct from human. When examining fragmentary remains, it can be relatively simple to recognize non-human from human if the section contains plexiform organization (Figure 1). Plexiform bone is not found in developing or mature human bone. And although plexiform is diagnostic of non-human bone, the presence of Haversian bone does not necessarily confer “human.” Canines, mature bovids, Pan and several other larger mammals develop some cortical Haversian bone, although the osteonal arrangement differs from the arrangement in humans at 100x. In nonhuman mammals that possess Haversian bone, osteons tend to be arranged in bands with 4-6 osteons arranged linearly (see below). As this phenomenon does not occur in human Haversian bone, it can often allow for species identification. Figure 1: Human Haversian bone compared to deer plexiform bone. 2 Once a “human” determination of bone has been made from fragments, what else can be added to a “forensic” investigation? Kerley (1965) published a unique and ingenious method using histomorphometric evaluation of human femoral midshaft cross sections for assessing age at death. He discovered a positive correlation between advancing age and subtle osteonal signatures. However successful, the primary sanction preventing wholesale utilization of this technique is that many times there are no macroscopic cortical landmarks to diagnose “femur.” Hence, is the Kerley method developed from femora appropriate for other long bones? In short, are the intra-(within) and even, inter- (between bones of the same skeleton), histomorphometric signatures identical among all long bones in the body or are there differences in osteon populations that must be considered to most accurately estimate age? This has not been studied with respect to the major bones of the axial skeleton. While the rib and clavicle have been successfully utilized (particularly in Stout’s research designs) out of convenience at autopsy, there demands specific criteria established for each long bone. Furthermore, Samson and Branigan (1987) discovered that their histological/ gross morphological age method for fragmentary remains was highly inaccurate for females, leading one to believe different cortical regions (between bones) may be gender specific targets. This study will qualify and quantify the degree of bone microstructural differentiation, i.e., osteon number, fragmentary osteon number, percent circumferential lamellar bone and number of non-Haversian canals (per view), between (inter-element of one skeleton) and within (intra-element) the long bones of the human skeleton. This is a study whose time has come again and again as every 3 researcher in bone histology has envisioned such a comprehensive study to “once and for all” lay to rest by comparison and contrasting any inter and intra-skeletal histomorphometric variation. Specifically, this study will examine serial diaphyseal and metaphyseal “shaft” sections from proximal to distal midshaft of each appendicular long bone of the human skeleton. This study utilizes Kerley’ s (1965) four quantification categories, i.e., non-Haversian canal number, osteon number, and osteon fragment number, and percent circumferential lamellae, to estimate age as well as quantifying the differential structure counts from human femur, tibia and fibula based upon section location. Each long bone is evaluated metrically following the Chicago Standards (after Buikstra and Ubelaker, 1994). From each midshaft one-centimeter increments are marked proximally and distally, which results in twenty-five to forty segments per bone. Three thin sections are then cut from each one-centimeter segment using a high-concentration diamond blade mounted on a Buehler Isomet 1000 saw. This technique employs a modification of the methods individually created by Stout and Ubelaker over their 25 years of bone histology methodology. The Kerley quantification categories are used to enumerate the same microstructures in the humerus, radius and ulna to identify structural change from proximal to distal. Age estimation, via the Kerley method, was not created from pectoral girdle elements, as the method was not intended for these bones. All sections are subjected to quantification identical to Kerley’s quadrant (anterior, posterior, medial and lateral) using a Leica DMRX light microscope at 5x, 10x and 20x power magnification. Morphometric analysis of the Kerley’s quantification categories was 4 conducted using Image-Pro Express software on the Dell Optiplex GX270 (see Chapter 4). Differentiation within and between bones was examined statistically. Once the diagnostic subtleties of human bone microstructure are documented, a sister project, will determine if various histological aging methods, i.e., Stout and Paine (1992), Ericksen (1991), Singh and Gunberg (1970) and Thompson (1979), can accurately estimate age regardless of bone. From this experimental design, a newly revised aging method will eventually be developed to precisely age fragments regardless of their point of origination in the skeleton and provide a baseline “gold standard” to achieve standardization and foster more wholesale utilization/collaboration. Additionally, in the future, the same method will be systematically applied to histomorphometric features of plexiform bone in those nonhuman mammals, i.e., dog, deer, cow, pig and bear, most commonly mistaken by law enforcement as human (and if small enough lacking diagnostic landmarks, confusing to osteologists). Non-human species will be examined at various ages to discern the initial appearance and developmental longevity of Haversian bone. Also, conversion of non-human plexiform to Haversian bone creates diagnostic confusion when attempting identification of fragmented remains. This study of non-human histomorphometric signatures from serial sections may alleviate mis-identification. 5 Chapter 2: Bone Biology, Embryology and Histology Bone is not a static organ within the body; it is always changing, always being modified by both mechanical and metabolic processes. The study of bone histology or microstructure has many far reaching uses in clinical, practical and research settings. It is imperative, therefore, that those who study the skeleton are familiar with the processes which form the bones that we study. Unless noted, the following account is derived from a detailed discussions on skeletal embryogenesis by Bronner and Farach-Carson, 2004; Carter and Beaupré, 2001; Karaplis, 2002; Marks, Jr. and Odgren, 2002; and Martin et al, 1998. Embryonic Development of Bone Within the embryo there are differential cells that lead to the formation of the skeleton. The neural crest cells contribute to the formation of the craniofacial skeleton. Somites differentiate into sclerotomes to aid in the formation of the axial skeleton, while the mesodermal cells originating from the lateral plate aid in the formation of the appendicular skeleton. All three types of embryonic building blocks contribute to skeletogenesis through the cellular movement to specific sites. The interaction between epithelial and mesnechymal cells facilitate the condensation of cells that further differentiate into osteoblastic and chondroblastic cells. The axial skeleton forms through a process known as somitogenesis. This is the process of segmentation of the paraxial mesoderm from the axial and lateral 6 mesoderm forming tissue on either side of the neural tube (Figure 2). The tissue forms into somites. Somites are paired blocks of mesoderm that align along the neural tube and the notochord. At twenty days post fertilization the first somites are noted within the developing embryo and their numbers increase as the embryo develops. At 23 days after fertilization there are ten somites aligned along the neural tube and notochord. This number jumps to twenty at 26 days post-fertalization and are associated with upper limb bud formation. Within the next two days of gestation, the somite population is elevated to thirty and is associated with the condensation of mesenchymal matter into a rudimentary skeleton and the appearance of lower limb buds. Schlerotome formation, directed by the notochord, is fueled by a secretory hormone called Shh (Sonic hedgehog) which initiates formation of these cells. Figure 2: Somite alignment along neural tube. Adapted from Larsen (1997). 7 The specific biochemical pathways that causes mesenchymal stem cells to become osteoprogenitor cells and to further differentiate into osteoblastic cells has not yet been defined (Aubin et al, 1993). The axial and appendicular skeleton arises from a cartilaginous framework in which cartilage grows rapidly through the division of chondrocytes. Growth of bone within the body occurs in two distinct methods: Intramebranous ossification and endochondral ossification. The intramembranous method of bone development occurs within the flat bones of the body, including the bones of the cranial vault, the facial bones and portions of the clavicle, scapula, sternum and pelvis. During this process mesechymal cells directly differentiate into osteoblasts which begin to secrete bone matrix (osteoid) within a membrane covering. Growth of long bones occurs as a result of endochondral ossification. The endochondral ossification of long bones at the growth plate is usually split up into a series of either four or five zones (Figure 3). For this discussion I will be referring to the four zones termed reserve (resting), proliferative, hypertrophic ,and provisional mineralization. The reserve (resting) zone is the most distal zone from the ossification center. It is not actually resting, in fact, it is active in the formation of both length and width of the bone. In this zone, stem cells (mesenchymal cells) are differentiated into full chondrocytes. In the proliferative zone these chondrocytes divide repeatedly and arrange into columns. The cells themselves becoming disk like and produce type II collagen and proteoglycans. In the hypertrophic zone, the chondrocytes mature (stop proliferating) and accumulate glycogen within their cytoplasm, which causes them to secrete their matrix. The chondrocytes are in the early stages of apoptosis 8 Figure 3: Zones of endochondral ossification. Adapted from Warwick and Williams (1973). 9 (programmed cell death) in this stage. The cartilage is prepared by these chondrocytes for mineralization. In the zone of provisional mineralization the degenerating chondrocytes continue to hypertrophy as they reach the metaphysis and die (apoptotic death). The surrounding cartilage is then calcified. This process near the metaphysis accounts for the formation of trabeculae at the metaphysis. As each chondrocyte hypertrophies, it dissolves the cartilage around it. The large tunnels left by the dead chondrocytes allow invasion by blood vessels. This creates narrow bars of bone between the tunnels. Blood vessels invade the tunnels and are separated by trabecular calcified cartilage. Osteoblasts lay down bone on these trabeculae. Over time the cartilaginous cores of these primary spongiosa are replaced by bone. These structures are then called secondary spongiosa. Eventually, most of the trabeculae in the center of the metaphysis are resorbed for the formation of the medullary cavity. Bone Maintenance Cells There are several different types of bone maintenance cells. These include the osteoprogenitor cell (which eventually give rise to osteoblasts), osteoclast, osteocyte, and bone lining cell. Osteoclasts are bone dissolving cells formed by the fusion of monocytes in the red marrow. This fusion is initiated by parathyroid hormone release when the serum calcium concentration in the blood is low. The fusion of the monocytes forms this 10 multinuclear and functionally polarized large cell. Osteoclasts resorb bone by using its ruffled acidic border (ruffled area gives more surface area) to erode away bone. It first demineralizes bone away with acids and then dissolves the collagen with enzymes. Osteoclasts can move quickly and erode as much as tens of micrometers of bone away per day. Osteoclasts live in resorptive bays also called Howship’s lacunae (Figure 4). Osteoblasts are mono-nucleic cells that are formed from differentiated mesenchymal osteoprogenitor cells (Figure 5). The formation is a 2-3 day process triggered by mechanical or metabolic stress, i.e., serum calcium concentration too high triggering calcitonin initiation of mesenchymal cell differentiation. Osteoblasts produce osteoid, which is the organic portion of bone matrix and are responsible for laying down new bone. Osteoid is comprised of collagen, non-collagenous proteins, proteoglycans and water, making it a gel-like substance when deposited. The water is replaced by minerals (hydroxyapatite) as the osteoid mineralizes. Osteoblasts can lay down osteoid at a rate of 1µm per day during skeletogenesis and fracture repair. Figure 4: Osteoclasts in Howship’s lacunae. Adapted from Nanci (2003). 11 Figure 5: Osteoblasts laying down osteoid on a bony trabecula. Adapted from Yang and Damron 2002. Figure 6: Osteocytes. This image exhibits osteocytes within lacunae (left) and an osteocyte with it’s projections stretching into canaliculi (right). Adapted from Nanci (2003). Osteocytes are actually osteoblasts that become surrounded by bone matrix that the osteoblasts secrete. Their function is then converted to one of bone maintenance and communication. They reside in pores called lacunae and communicate with other osteocytes through tentacle-like projections which are housed in canaliculi (little canals) (Figure 6). The projections communicate through ion transfer at gap junctions. That is, the tentacles come close enough to each other to pass ions and small nutrients to one another through and positive/ negative flow. In this manner, the endosteum is connected to the periosteum and the proximal end of the bone is connected to the distal end allowing for communication (biochemical reciprocity) throughout the bone. 12 Bone lining cells are also converted osteoblasts, although they live on the bone surface (they do not become embedded in the osteoid). These are the cells which begin bone remodeling in response to mechanical stress (fracturing). Bone Formation and Maintenance Formation and maintenance of bone occurs by the processes of modeling and remodeling during growth and development. Modeling is the term used to describe the shaping of bones by osteoblastic and osteoclastic activity in different areas. In modeling, osteoblasts and osteoclasts work independently and change the bone size and shape. This process is continuous until maturity, then the rate decreases significantly. Modeling is necessary because longitudinal growth does not produce bone of the correct size and shape. Modeling can be resorptive or formative. For example, modeling at the metaphyses reduces the bone diameter in order to create a diaphysis. Osteoclasts work on the periosteal surface of the metaphysis to trim the shaft down to size. Modeling can also occur at the diaphysis to increase diameter or change the curvature. Long bone shafts increase in diameter by the slow addition of bone to the periosteal surface by osteoblasts while osteoclasts remove bone on the endosteal surface. Modeling also occurs on flat bones, although it is not as easy as it may appear. For example, in the growth of the cranial vault, bone cannot just be added at the suture because this would not alter the shape of the vault bones to accommodate the 13 growing brain. Instead the inner surface of the vault bones are resorbed while the outer surface has bone laid down on it in the appropriate manner to account for change in size and shape. The remodeling process can occur in both types of bone in response to stressors such as tension, applied load, hormonal changes and the amount of activity or inactivity that a bone undergoes (Bergman et al., 1996; Eroschenko, 1993). Remodeling refers to the repair of bone at a particular site using BMUs (Basic Multicellular Units). Harold Frost (1969) first coined the term BMU and was one of the first to describe the work of osteoclasts and osteoblasts as a combined effort, rather than independently resorbing and laying down bone. BMUs are comprised of both osteoblasts and osteoclasts working together. In remodeling, there is no change of size or shape of the bone, simply maintenance of the current structure. Remodeling occurs throughout life, although the rate is reduced after growth ceases. It is not a continuous process but episodic with each episode having a definite beginning and ending. Remodeling systematically removes older bone and replaces it with newly formed bone. This eliminates damage to old bone and prevents fatigue fractures which can occur in old bone through mechanical stress. This occurs throughout life. The deposition and resorption of bone is a constant process regulated by a number of systems within the body revolving around the level of calcium in the blood. Since the majority of the body’s calcium is stored within the skeleton, there is very little calcium in the blood itself. This blood calcium aids in the communication between cells, the contraction of muscle cells within the body as well as the activity of nerve 14 cells. Even slight changes in the blood calcium levels of the body could cause a disruption in any or all of these functions. Therefore, if the blood calcium levels are high, hormones are released that stimulate osteoblast activity and inhibit osteoclast activity. When the blood calcium levels are low, osteoclast activity is stimulated and osteoblast activity is inhibited (Schinke and Karsenty, 2002). This constant resorption and osteogenesis process leads to a distinct microscopic signature. When looking at a section of human bone, one can recognize Haversian systems (osteons) as concentric circles surrounding an inner circle which would have held a blood vessel or neurovascular bundle. Osteocytes, osteoblasts and osteoclasts can often be identified in the section. Within some sections, especially those from older individuals, it is quite common to see a newer (younger) Haversian system on top of another. The newer Haversian system is termed a secondary osteon (Figure 7). Figure 7: Cement (reversal) line. Digital image (200x) of a cement line around an osteon (arrow) in the femur midshaft demarcating the area in which the osteoclasts completed breaking down the bone and where osteoblasts began rebuilding the bone. 15 A clear reversal line distinguishes where the bone resorption ended and the bone building began. Secondary osteons tend to increase with age. As secondary osteons are laid down over older primary osteons, there tends to be an increase in fragmentary primary osteons (Figure 8) (Bergman et al., 1996; Stout, 1992). Remodeling determines the structure of most of the skeletal tissues, as well as their mechanical properties and resistance to fatigue or failure. BMUs are responsible for remodeling. The Basic Multicellular Units consists of about 10 osteocytes and several hundred osteoblasts. Frost (1969) indicates that the BMUs operate on the periosteal, endosteal and trabecular surfaces and within the cortical bone. There are three stages in the lifetime of a BMU: activation, resorption and formation. During activation, chemical and/or mechanical signals cause the fusion of monocytes to form osteoclasts. The resorption process is just that: resorption by osteoclasts. Once Figure 8: Fragmentary osteon associated with secondary osteons. A digital image (200x) of an osteon fragment (outlined) associated with an intact secondary osteon (arrow). 16 osteoclasts have resorbed a certain amount of bone, the formation stage begins with the differentiation of mesenchymal cells into osteoblasts over the next few days. The newly formed osteoblasts begin replacing the resorbed bone. The process of formation is much slower than resorption. An osteoclast can resorb tens of micrometers per day while an osteoblast can only form 1µm of bone per day. The resorption process takes about three weeks while the formation process in the same area takes about 3 months. The BMUs tunnel through compact bone longitudinally creating a secondary osteon (Figure 9). The tunnel cannot be completely filled in by osteoblasts because the blood supply needs to be maintained throughout the bone, thus the osteoblasts leave a new Haversian canal which houses both a return vessel and a supply vessel. BMUs replace 5% of bone per year on average in adults. Figure 9: BMU tunneling through old bone. Adapted from Kessel (1998). 17 Trabecular bone is remodeled in the same way as cortical bone, but the BMUs work on each of the trabeculae by scooping bone out and then refilling it, much like the digging of a trench. One differential form of remodeling is termed the Regional Accelerating Phenomenon (RAP) (Frost 1983). This is a sudden increase in the rate of remodeling due to traumatic injury. This can cause a temporary osteoporosis, due to the lag time between osteoclastic activity and osteoblastic activity. This is resolved within four months as the osteoblasts eventually catch up to the osteoclasts. This is all well and good but what does it mean to the lay anthropologist who just wants to look at osteons and tell a bit about them. Here are the six stages of an osteon’s lifecycle that summarizes all of these processes as described by Martin et al (1998): 1. Activation Differentiated cells are collected from a precursor cell population and are moved to the area in which the new osteon is to be formed. 2. Resorption Osteoclasts resorb bone by moving longitudinally through the bone at a rate of 40µm/day. The BMU has a diameter of 200µm and a resorption area of a few hundred µm long. 3. Reversal Transition from osteoclast activity to osteoblast activity takes several days and the reversal area is the lag space between the resorptive and refilling regions. The reversal line will eventually form the cement line. Process takes about 30 days. 4. Formation Osteoblasts appear at the periphery of the newly formed tunnel. They close approximately 12µm per day. They leave a central passage (Haversian canal) for blood vessels to maintain the BMU, bone matrix and to carry calcium and phosphorus back and forth. This phase takes 3 months. 5. Mineralization In this phase the osteoid is mineralized. There is a lag time of 10 days between the deposition of osteoid and the mineralization. Thus there is an osteoid front between the osteoblasts and the mineralized bone. Primary mineralization occurs within the first few days after mineralization starts. Secondary mineralization occurs as more minerals are added over the next several months. 6. Quiescence After the BMUs have completed their process of remodeling the osteoclasts disappear and the osteoblasts become osteocytes and maintain the bone. 18 Bone Mineral Composition Bone is comprised of collagen, minerals, ground substance, non-collagenous proteins and water. The collagen is a structural protein. The mineral component is mostly hydroxyapatite <Ca10(PO4)6(OH2)>. The ground substance in comprised of proteoglycans, and the non-collagenous proteins include osteocalcin that is secreted by osteoblasts and aids in bone mineralization. Types of Human Bone There are two types of bone formed and maintained throughout the life. Young bone is woven and adult, mature bone is lamellar. Woven bone is immature and is atypical in the body after the age of five except when bone formation occurs as a result of fracture or surgery. Woven bone is characteristic of the embryonic skeleton where it develops from calcified cartilage during the process of endochondral ossification (as described). It is very flexible but it can be easily deformed as the collagen fibers and minerals are arranged in a haphazard formation. This type of bone is fairly weak when compared structurally and biochemically to its “mature” lamellar counterpart. Thus, woven bone is eventually replaced by more rigid lamellar bone. Lamellar bone forms more slowly than woven. It is highly organized and contains concentric lamellar layers. There are two types of lamellar architecture: 1) the classic lamellar structure and 2) heliocoidal structure (Figure 10). 19 Figure 10: Plywood lamellar architecture. Digital image depicting plywood orientation of lamellar bone (Adapted from Photographic Atlas of the Body -2004) The classic lamellar structure has lamella that are built up on layers of collagen and laid down in one orientation. The next layer is put down at a right angle to the first layer. The heliocoidal lamellae are laid down collagen fibers in different direction. This lamellar formation is actually not individual lamellae but it can still show lamellar structure. Two layers frame the microscopic structure of bone: periosteum and endosteum (Figure 11). The periosteum is an external fibrocellular sheath that contains collagen fibers and fibroblasts, which, in turn, forms an inner osteogenic/nourishing layer on top of the compact surface. The endosteum lines the inner marrow cavity surface as well as all Haversian and Volkmann’s canals. It consists of osteogenic cells and thin reticular fibers (Bergman et al., 1996). 20 Periosteal Endosteal Endosteal Periosteal Figure 11: Human bone periosteum and endosteum. Macroscopic view of a human femur sectioned at midshaft showing the periosteal surface and endosteal surface (left). The microscopic view of human rib (100 X) showing the periosteal and endosteal surfaces (right). Mature Bone Adult bone consists of two forms of bone: trabecular and compact bone (Figure 12). Trabecular bone, also known as cancellous or spongy bone, is the internal porous bone found in irregular bones, flat bones, and the articular ends of long bones. Cancellous bone is the latticework of bony spicules or trabeculae that are within the shaft and the epiphyses (Ross et al., 1989). The bony spicules or trabeculae are beams of bone that form inner scaffolding. In life, the pores within trabecular bone are connected and filled with marrow. The bone matrix is laid down in the form of bony spicules (trabeculae) that tend to be <200µm thick. The arrangement of these trabeculae is irregular although it is often in an orthogonal formation. 21 Figure 12: Compact and cancellous bone. A 35mm photograph of a proximal humerus sagittally sectioned. Compact bone, on the other hand, also known as cortical bone, is the dense bone found in shafts of long bones and forms the outer cortex that covers trabecular bone. The micro-organization of this bone consists of many small formations that allow the inside (endosteum) of the bone to communicate with the outside of the bone (periosteum) (Figure 13). These include Haversian canals, Volkmann’s canals, and resorptive bays. Haversian canals are narrow trenches aligned on the long axis of the bone and contain nerves and capillaries that allow nutrients to move throughout the entire bone matrix (Figure 14). Volkmann’s canals are short transverse canals connecting Haversian canals to one another and allowing communication to the outer bone surface through blood vessels. Resorption bays (also known as Howship’s lacunae) are scoured out areas in which osteoclasts live during initiation of the remodeling process. The porosity of both types of bone is dynamic and can be affected by pathologies or as the bone adapts to mechanical or metabolic stimulus. 22 Figure 13: Schematic of human bone structure. Adapted from Martin et al (1998). A B Figure 14: Microscopic view of Haversian bone. The image on the left (A) shows a microscopic view of a human tibia (400X) showing a circular Haversian canal (indicated by arrow). The image on the right (B) depicts Haversian bone (osteons) as seen in the same section of human tibia at 100X (encircled). 23 Thus, obviously, trabecular bone can become more compact and compact bone can become more porous. Any change in the original porosity of the bone can affect the mechanical/structural properties of the bone. Compact bone can be further divided into primary and secondary. Primary bone is on an existing bone surface (periosteal) during growth of the skeleton. There are two types of primary bone found within different species: circumferential lamellae and plexiform. Circumferential lamellar bone has lamellae that are laid down in a parallel orientation to the bone’s surface. Blood vessels are encompassed by these circular lamellae, creating Haversian canals longitudinally throughout the bone. The blood vessels are used to move minerals, nutrients and remodeling cells to the section of bone that needs attention. This type of primary bone is found in humans. Plexiform bone is a mixture of both woven and lamellar bone. Plexiform is in a brick wall pattern because the vascular structure is rectilinear, thus creating the image of individual bricks. This type of bone is typical in large fast growing animals, such as horses, cows and goats. Secondary bone is formed by the resorption of existing bone and the laying down of new lamellar bone in its place. This is a process known as remodeling. Secondary osteons usually consist of approximately 16 consecutive circumferential lamellae that have formed surrounding a Haversian canal that houses blood vessels and nerves. Secondary osteons are surrounded by a cement line which demarcates where the osteoclasts ended their resorption process. Most of the compact bone in adult humans consists of secondary bone, leaving a characteristic morphology of complete osteons and pieces of old osteons (interstitial lamellae) within a thin section 24 of bone. Interestingly, trabecular bone in adult humans is also mostly secondary bone and it is turned over from primary to secondary bone more quickly than compact bone. It is quite unusual to see any osteon formation within trabecular bone, even secondary trabecular bone because the osteons are too large (200µm) to fit within the thin trabeculae (<200µm thick). 25 Chapter 3: Anthropological Uses of Bone Histology Historically, there have been numerous attempts to use bone microstructure to age individuals (see Robling and Stout 2000). While it is by no means a highly accurate technique, some researchers claim to be able to histologically age individuals within three years of their actual age (Thompson 1979) with their specific technique. Histological aging is, however, a way to age individuals when there are no other macroscopic means to identify age. It is also a great way to corroborate macroscopic age estimations. This microscopic methodology is so important in fact that at the most recent American Academy of Forensic Sciences Meetings (2005), an entire morning workshop hosted by Drs. Helen Cho, Robert Paine, Sam Stout and Douglas Ubelaker, was dedicated to “Forensic Bone Histology”. The topics covered included the determination of human versus non-human at the microscopic level, a review of histological age estimation techniques, a discussion about the diagenetic changes associated with the taphonomic effects of environment on bone and how this diagenesis can effect histological age estimation, and the effects of malnutrition and starvation on bone microstructure. The standing-room only workshop reinforced major components in the histological analysis of bone, and while most presenters suggested that more research should be undertaken using bone micromorphology, none suggested any new methods of histological aging, or suggested alternative sampling sites. Currently, forensic anthropologists are left with the old standbys for histological aging. 26 There are many techniques to estimate age and each is not without its problems or critics. It is difficult to learn to age remains in this fashion and is even more difficult to master any one technique. In fact, many of the techniques use specific microstructures which may or may not be used by the other technique, making it a confusing process. Below is a discussion of some of the aging techniques in the literature with a critique of the usefulness and practicality of each. In 1965, Ellis Kerley pioneered the use of histomorphometry as an age at death estimator. Using transverse sections from the midshafts of the femur, tibia and fibula, Kerley quantified the number of osteons, number of fragmented old osteons, percent of circumferential lamellar bone (primary bone) and number of nonHaversian canals within each section at four fields situated at the anterior, posterior, medial and lateral portions of the section. For each thin section the quantities identified in each of the regions was summed across the four regions. Kerley’s results indicate that 87.3 % were within 5 years of their actual chronological age and that all of his specimens were within 10 years of their actual age. There are problems with this technique, including the fact that you cannot use it if you have no pelvic limb bones or if you have fragmentary bones since you must have a complete transverse section from the midshaft. Additionally, the definitions of the microstructures defined are imperative since Kerley defines intact osteons as being be 80% complete without remodeling evidence. This is different than the definition later suggested by Stout (1992). Another methodological issue is that the original article did not address field size which is important since structures are counted even if they are only partially in the field. 27 Kerley and Ubelaker (1978) tried to standardize this shortcoming of Kerley (1965) with an estimation of the original field size as 2.06mm2 and added a correction factor for field size in case the field size differed from this value. Stout and Gehlert (1982) suggest that in using this method one should use field size as close to 2.06mm2 since the structures are not randomly distributed throughout the section and may skew results. In 1969, Ahlqvist and Damsten published a modification to the Kerley method. To simplify the method as well as avoid the linea aspera, which may skew results given muscle attachment and mechanical stress. To avoid the linea aspera they used quadrants equi-distant between the Kerley quadrants. They also employed a counting reticle at the level of the section which consisted of a one hundred square grid to gather the percentage of the grid was covered by Haversian bone and then they averaged counts across the four fields. The problems with this technique include the fact that their study only looked at the femur and again requires a complete transverse section. Stout and Stanley (1992) suggested that the percentage of Haversian bone had a non-significant relationship with age but osteon counts had a significant relationship with age. This would indicate that this characteristic should not be used, or at least not alone as it is in this study. Stout and Gehlert (1982) compared the two methods and determined that Kerley’s original method, however, was better at age determination than the Ahlqvist and Damsten method. In 1992, Stout and Paine published a method of age determination based on the middle third of 6th rib and clavicle midshaft. These bones were used for a number 28 of reasons including that anthropologists don’t generally like to section long bones and rib and clavicle are not needed intact for any osteological measurements. Additionally, the sternal rib end aging technique is not affected since the section is taken within the rib shaft. Not to mention the fact that ribs are easy to extract at autopsy for the purpose of study. This technique is also able to be used on a fragmentary skeleton. From the two sections, the number of intact and fragmentary osteons per unit area were identified using a counting reticle. As mentioned above, they define intact osteon as 90% complete while everything else is considered a fragment. Stout and Paine (1992) suggest that at least two sections of each bone should be used in order to minimize sampling error that can exist even in serial sections (Frost 1969). The total osteon density is then determined by the sum of the intact and fragmentary osteons and then put into a regression equation. This technique seems to have minimal methodological and practical problems other than the fact that it only works on clavicle and rib and requires a complete cross sections. There are a few methods that do not require a complete transverse section of bone. One example is Singh and Gunberg’s (1970) method which uses small sections taken from the anterior femur and tibia and the posterior mandible. They look at two fields at the periosteal portion of the bone looking for three variables. Their study claims to give age estimation in males within 6 years of the actual age. The study does not examine females and suggests that there are no sex differences in females according to a small comparative study. Besides the lack of females in this sample, 29 the male sample is skewed to the older age ranges with a mean age of approximately 64 years old. Thompson (1979) describes a method of age assessment that uses tiny cores of bone taken from the femur, tibia, humerus and ulna. This study uses over 100 individuals, including females. It looks at 19 different variables including macroscopic (cortical thickness) and microscopic (secondary osteon populations) details. Thompson suggests, by testing the method on 8 forensic cases that an age range as low as ± 3years from the known age. In another article, Thompson et al (1981) test the method against 28 forensic cases and come up with a mean age range of ±7.6 years and refer to an equation that is not in the 1979 article. Stout (1992) suggests that he has no idea what equation is being used to come up with these ranges. Ericksen (1991) used a sample of over 300 individuals with a broad age range to examine her method of histological aging. She used a wedge of bone from anterior femur at midshaft. Using pictures and the microscope simultaneously, she counted up the secondary osteons, osteon fragments, non-Haversian canals and percentage of unremodeled bone. Once again, the weakness of this technique is that it has only been used for the femur and you must have most of the femur (at least the anterior midshaft) to use it. Samson and Branigan (1987) developed a method of histological age estimation using highly fragmentary or weathered bone. They examined characteristics like mean cortical thickness and number of Haversian canals. This gives an age range for males of ±8 years, though it’s utilization in the forensic setting 30 may be minimal as there is an error rate of +/- 16 years for females. If it is difficult to identify which bone it came from how can one assess whether it is male or female. An initial attempt by Benedix (2004) to rectify these shortcomings in sorting fragmentary remains explored the differentiation between the human and non-human species at the microscopic level, with his main focus on the animal species found is Southeast Asia whose fragmentary remains are often commingled with or mistaken for those of missing servicemen from past military conflicts. Benedix discovered that while some animal bones can be distinguished from human at the microscopic level, it may be very difficult to distinguish between some fragmentary animal remains and the remains of humans when there are no macroscopic morphologies available to make the distinction as their histological structure is very similar. According to Robling and Stout (2000) there are many problems with aging of humans according to their microstructure. In this article they present a figure that organizes different bone microstructure characteristics against whether they increase, decrease or stay the same with age. They list the different publications that indicate these findings and they looked at some of the most commonly measured microstructure characteristics such as osteon size and Haversian canal size. Using Haversian canal size as an example, there are publications that say that Haversian canal size increases with age, others that say it decreases with age and still others that say there is no change in the size associated with age. This discrepancy in different bones of the skeleton and by different researchers could create quite a problem when trying to discern problems with techniques or identify new techniques. 31 Another key issue with histological aging of human bone is that most methods utilize only the midshaft. In a cursory look at the numerous methods, the human skeleton is well represented: femur (Samson and Branigan 1987; Narasaki 1990; Drusini 1987; Eriksen 1991; Thompson 1979; Singh and Gunberg 1970; Ahlqvist and Damsten 1969; Kerley 1965; Kerley and Ubelaker 1978), tibia (Kerley 1965; Kerely and Ubelaker 1978; Singh and Gunberg 1970; Thompson and Galvin 1983), fibula (Kerley 1965; Kerely and Ubelaker 1978), ulna (Thompson 1979), clavicle (Stout et al 1996), 4th rib ( Stout et al 1994) and 6th rib ( Stout and Paine 1992), 2nd metacarpal( Kimura 1992), occipital (Cool et al 1995), mandible (Singh and Gunberg 1970), and humerus (Thompson 1979; and Yoshino et al 1994) . The majority of the long bone methods for histological aging require sectioning at midshaft, regardless of whether the technique requires transverse sections or cores. Obviously, this begs the following questions: What happens when you do not have a midshaft or when the bone is fragmentary? Are these methods applicable to every part of the shaft? After a thorough literature review on the subject, this author can find no previous research dealing with the osteon population throughout the shaft, whether it is static through the length of the shaft or whether the population differs depending upon muscle attachment sites or proximity to articular surfaces and therefore trabecular bone. It makes intuitive sense that the areas of bone that are subjected to more mechanical stress throughout life would show more osteonal turnover than other areas. That is to say, that the pulling of muscles directly on the bone at muscle attachment sites must cause more bone remodeling than occurs at non-attachments sites simply due to the strain placed on the bone at that site. Moreover, areas of the 32 shaft where the cortical bone surrounds trabecular bone, near proximal and distal articulating surfaces, may have a lower osteon population simply due to the thin the cortical bone. There are metabolic and mechanical processes which can affect osteonal remodeling and thus affect the accuracy of histological aging techniques. Some of these have been enumerated by Frost (1985) which include hormonal response, regional trauma, usage or non-usage (disuse atrophy), paralysis, and metabolic diseases. Additionally Regional Accelerating Phenomenon (RAP) (as discussed earlier) can be produced by fracture, modification to the bone via surgery or by the inflammatory process (Frost 1983). These areas modified by the RAP can definitely affect the accuracy of the aging techniques. As discussed in the next section, other metabolic and systemic disorders can affect the bone microstructure and thus affect the ability to accurately age using bone histology. Bioarchaeological and Paleopathological Uses of Bone Histology The use of bone histology has tremendously affected paleopathology and for that matter, bioarcheology, as a whole. The microscopic analysis of human bone has allowed for a more complete analysis of skeletal remains. That is, the use of bone histology has allowed for the identification of diseases on an individual basis, the identification of disease distribution and the history of disease within a population (Schultz 2001). Bone histology can also help to identify disease loads, living conditions and general lifeways of ancient populations. According to Larsen (1997), 33 histological morphology can indicate stress within a population since remodeling rates of human bone are affected by disease and nutrition. Stout (1989) suggested that based on the differing histological signatures maize agriculturalists have greater remodeling rates than hunters and gatherers. He suggests that this reflects effects of overproductivity of parathyroid hormone resulting in low calcium and high phosphorous concentrations, thus (as described earlier) osteoclasts are over stimulated to break down bone (increasing remodeling). Larsen (1997) even discusses that the mineralization period (Stage 5 of the osteons lifecycle) can be influenced by stress. He also gives an example using bone histology as a means of determining modes of subsistence and compares the osteon structures of Eskimos (primarily meat eaters), Arikara (foraging and farming), and Pueblo (primarily maize based subsistence). This research suggests that Eskimos have a higher rate of type II osteons (secondary (smaller) remodeling sequences) than the other two groups because of their increased calcium intake from meat consumption. Schultz has furthered the study of bone histology in paleopathology with the diagnoses of diseases of the skeleton using histology. This prolific writer has pushed the differential diagnoses of pathological conditions to new heights through his use of microstructure analysis of ancient populations. In fact, his contributions are so important to paleopathology that in Ortner’s 2003 volume on the identification of pathological diseases (the most extensive descriptive analysis of bone disorders and the newest bible in human paleopathology) there is an entire chapter devoted to the differential diagnoses of bone disease by histological analysis. In addition to the normal uses of bone histology including the identification of fragmentary remains as 34 human or non-human and microscopic aging techniques, Schultz’s research in bone histology has identified the bony signatures of metabolic diseases as well as physical /mechanical infirmities (such as atrophy) that cannot necessarily be identified macroscopically. Schultz (2001, 2003) indicates that bone histology can also be used for the identification of preservation state of remains. This can be helpful in the determination of whether or not further chemical/genetic analysis of these remains could be successfully undertaken. This can save the needless waste of money on the analysis of poorly preserved bone. Schultz (2003) nearly mandates the use of microscopic techniques for differential diagnosis of disease by paleopathologists. He suggests that the histological signature could identify bone tumors, lesions, specific and non-specific bone inflammations, metabolic disorders, age associated changes, and early stages of bone disease that are not macroscopically identifiable. This is evidenced by his discussion of a population that was examined twice, first macroscopically then microscopically. The initial diagnosis concluded that there was high prevalence of osteomyelitis and anemia and low incidence of meningeal irritation within this population. The microscopic analysis revealed that the anemia and osteomyelitis frequency were actually significantly less than originally thought and that the meningeal irritation frequency increased. Additionally, microscopic analysis identified rickets in bones that were macroscopically identified as osteomyelitis. Schultz (2001) argues that the microscopic determination of bone disease is more reliable than any macroscopic evaluation. In short, any disorder that can cause a 35 bony response can be identified with the use of histology. He indicates that treponemal diseases, rickets, scurvy, meningitis and leprosy can usually only be diagnosed with histology and the microscopic changes and stages of bony destruction cause by venereal syphilis and yaws. According to Schultz (2001, 2003), the value of bone histology in bioarchaeology and paleopathology is use as an epidemiological tool to assess disease effects on ancient populations. In many ways his research may well help to alleviate one of the major theoretical problems in bioarchaeology today: the osteological paradox as described in Wood et al (1992). This deals with the hidden heterogeneity within populations. The individuals in a population are an unknown mixture of people who each had differing frailty or susceptibility to disease. This article gives an example of the paradox in a fictitious population with three subgroups. They describe a major stressor (disease) that differentially affects these three subgroups. The first subgroup does not encounter the stressor. The second subgroup is moderately affected by the stressor and it produces bony lesions within the population. The third subgroup is affected significantly by the stressor, to an end that most of its members die quickly even before lesions can form. Wood and coworkers conclude that just looking at the skeletal series (which is all bioarcheologists have to look at) one could probably only identify two groups of skeletons macroscopically (lesions and no lesions). From two groups one could not glean the fact that there were three groups experiencing varying risks of disease and death. It is possible however, that with the use of histological analysis early bony changes (prior to death) could be identified, thus splitting the population back into three groups. 36 The Future of Bone Histology in Anthropology Even given the sanctions preventing wholesale, systematic destruction of bone from paleontological, bioarchaeological, historical and forensic sites for histological assessment, there is much to be learned about the microscopic variables that vary with age, sex, and within and between bones of the same individual. Continued research will provide the necessary insights and results that enable us to accurately diagnose disease using clinical exemplars, in addition to identifying victims from fragmentary remains and bring closure to cold case files that deal with highly fragmented human remains. 37 Chapter 4: Materials and Methods This research was performed in the Mineralized Tissue Histology Laboratory in the Department of Anthropology at the University of Tennessee. This laboratory houses equipment for thin sectioning, epoxy resin embedding and microscopic evaluation bone and dental thin sections and this study made full use of these thin sectioning, embedding, and microscopy materials. Three sample sets of bone from three individuals were utilized for this blind study to enumerate intra and inter-skeletal differences. The bone sectioned in this study was from three sources: 1) processed elements from amputated limbs donated to the osteological teaching collection in the Department of Anthropology at the University of Tennessee, 2) an historic burial from upper east Tennessee from the Tennessee Bureau of Investigation and 3) two forensic cases through the Regional Forensic Center at the University of Tennessee Medical Center. None of the demographic information on these individuals was known to this researcher, although the data does exist within a database. Each sample consisted of the following complete elements: humerus, radius, ulna, femur, tibia and fibula (Figure 15). Each bone of the sample was measured using all standard osteometry established by Chicago Standards (see Buikstra and Ubelaker, 1994). The results of all measurements are presented in Appendix A. The midshaft of each bone was marked on the bone and 1 centimeter increments were marked moving proximally and distally from midshaft. Each midshaft segment was denoted with an “M”. Distal sections were denoted D1, D2, D3….Dn, where D1 was the first section taken moving 1 38 Figure 15: Elements of each sample. Digital image of the six appendicular elements used in each of the three sample sets. From left: Humerus, Ulna, Radius, Femur, Tibia and Fibula. centimeter distal from midshaft. Proximal sections were denoted P1, P2, P3….Pn, where P1 was the first section moving 1 centimeter proximal from midshaft (Figure 16). Each specimen was given a catalog name such as, HS-B-2-D3, where the first element was the genus and species abbreviation (HS-Homo sapiens), followed by the specimen letter (A-C), followed by the element type abbreviation (1-Humerus, 2Radius, 3-Ulna, 4-Femur, 5-Tibia, 6-Fibula) and ending with the section letter and number combination (D3- 3rd distal segment-3 centimeters from midshaft). The method of analysis required a series of thin sections produced from each of the shaft sections. To facilitate sectioning, the bones were cut in half using a Dremel multi tool. Each element is cut halfway between the midshaft marker and 39 Figure 16: Scoring of the bones for sectioning. A digital image of two sample sets of bones after each element had been scored at each one centimeter increment from midshaft. Note that at this point the epiphyseal ends have already been removed and the long bones have been halved near midshaft. either the P1 or D1 marker, but never exactly at midshaft, in order to preserve the actual midshaft for thin sectioning (Figure 16). The most proximal and distal portions (epiphyses) of the bone were removed near the metaphyses. Thin sectioning began at midshaft for each skeletal element and moved in 1cm increments proximal and distal down the shaft of specimen A, while moving at 3 cm increments proximal and distal down the shaft for specimen B, and C. The change in the increments of sectioning was directed by microscopic review of the first specimen noting little or no change in histostructural populations within the 3 cm increments (further corroborated by statistical analyses of the differentiation within the 3cm increments, see discussion below), as well as the facilitation of completing the three specimen in a timely manner. Three consecutive 0.8 millimeter sections were removed at each increment to ensure that one of the three specimens would be appropriate for microscopic analysis. So, although there are 25 sections for femur A, 75 thin sections were made 40 (Figure 17). The thin sections were made using a Buehler Isomet 1000 saw with a 15 HC diamond-edged blade at the speed of 200 (Figure 18). Each thin section then attached to a labeled glass slide (which included catalog number; then anterior, posterior, medial and lateral orientation arrows; and element side and name) using Permount mounting media and covered with a glass cover slip (Figure 19). After the Permount cured by air drying (this can take at least two weeks) they were viewed using a Leica DMRX research light microscope at 16X, 50X and 100X magnification. From each 1centimeter segment, the clearest slide was used for this analysis. This histostructural analysis employs the protocol adapted from Kerley (1965) which used transverse sections from the midshafts of the femur, tibia and fibula. Kerley quantified the number of osteons, number of fragments of old osteons, percent of circumferential lamellar bone (primary bone) and number of non-Haversian canals within each section at four fields situated at the anterior, posterior, medial and lateral portions of the section (Figure 20). An image of each field was examined for quantification of structures and digitally captured using the Leica DMRX research microscope equipped with a Sony digital camera link to a Sony mixer with digital image capture and color manipulation capabilities (Figure 21). From there, a field size identical to Kerley’s (2.06 mm2) was superimposed onto the section so that the cutoff area was clear using Image-Pro Express software on 41 Figure 17: Macroscopic Cross Sectional Variation of Femur. A digital image representing the proximal sections (P1-P12, midshaft (M), and distal sections (D1-D12) taken from femur A. 42 Figure 18: Buehler Isomet 1000 thin- sectioning saw slicing a cross section of fibula. Figure 19: Microscopic Slide of Sample A. A digital image representing a microscopic slide of the fifth proximal section (P5) taken from femur A. Note the catalogue number (HS-A-4-P5), the bone side and name and the orientation grid (top left). 43 50x 100x 50x Figure 20: Features measured in the Kerley method of histological age estimation. There are four categories of microscopic structures quantified in Kerley’s aging method. First, the number of osteons within the field are quantified. This image (top left) has several (not all) intact osteons circled in red. The next image (top right) depicts Kerley’s second category of fragmentary osteons (arrow points to fragment). The bottom image depicts the final two categories in Kerley’s method: number of non-Haversian canals (elipse) and percentage of the bone in their field covered by circumferential lamellae (arrows). Figure 21: Capturing four microscopic fields. This digital image shows the four microscopic images captured from one segment of this femur. One image is captured from the anterior, medial, posterior and lateral segments of the thin section of bone. 44 Each of the four categories of the Kerley method was quantified for every thin section (approximately 130 slides) of the humerus, radius, ulna, femur, tibia and fibula. Each osteon, fragment and non-Haversian canal was labeled to facilitate counting (Figure 23). The percent of non-Haversian bone was estimated using a Dell Optiplex GX270 desktop computer (Figure 22). Morphometric analysis of the four Kerley quantification categories was conducted. quartered grid within the field. All four categories were quantified for the anterior, medial, posterior and lateral fields for each of the thin sections and were recorded in Microsoft Office Excel 2003. Additionally, the femur, tibia and fibula quantifications were used to estimate age after Kerley and Ubelaker (1978), as these are the skeletal elements that are used for age estimation. These equations include: Femur Osteons Y= 2.278+0.187x+ 0.0026x2 +/- 9.19 years Fragments Y= 5.241+0.509x+0.017x2-0.00015x3 +/- 6.98 years Lamellar Y= 75.017-1.790x+0.0114x2 +/- 12.52 years Non-Haversian Y= 58.390-3.184x+0.0628x2-0.00036x3 +/- 12.12 years Tibia Osteons Y= -13.4218+0.660x +/- 10.53 years Fragments Y= -26.997+2.501x-0.014x2 +/- 8.42 years Lamellar Y= 80.934-2.281x+0.019x2 +/- 14.28 years Non-Haversian Y= 67.872-9.070x+0.440x2-0.0062x3 +/- 10.19 years Fibula Osteons Y= -23.59+0.74511x +/- 8.33 years Fragments Y= -9.89+1.064x +/- 3.66 years Lamellar Y= 125.09-10.92x+0.3723x2-0.00412x3 +/- 10.74 years Non-Haversian Y= 62.33-9.776x+0.5502x-0.00704x3 +/- 14.62 years The associated age estimates were compared within and between bones of the same individual. That is, each section (i.e. D3, P6, M) taken from femur A will have 45 Figure 22: Superimposition of 2.06mm2 field size on captured image. A digital image captured from the femur of Specimen B at segment P3. The circle is the exact 2.06 mm2 field superimposed onto the image to ensure that only the microstructures within this area are counted. Figure 23: Labeling of the microstructures within the field. A digital image of an enlargement of the field size depicted in Figure 22 with the osteons and fragments digitally labeled using Image Pro Express 4.5 software. The osteons are marked with a dot and a corresponding number preceded by an “O” while the fragments are marked with a line and corresponding number with a preceding “F”. 46 separate age estimations calculated for that section. These estimations were compared within the femur and also compared to the tibia and fibula of specimen A. A factorial ANOVA analysis was run on the twenty-five segments of Femur A to determine if there were significant differences between mean osteon count, mean fragment number and mean percentage of non-Haversian bone within the 3 cm segments. This analysis would determine if sectioning could be reduced to every third centimeter, or whether there was enough differentiation within a three centimeter segment to warrant sectioning at every centimeter. The means for osteon number, fragment number and the percentage of nonHaversian bone were statistically compared over the four fields (anterior, medial, posterior and lateral) at across the common segments for the population (samples A,B, and C combined) using repeated measures ANOVA in SPSS. Only the common segments could be compared, that is, only segments that all three samples had in common could be used to compute a variance for the population. The number of nonHaversian canals was not considered in this analysis since a majority of the sections did not exhibit non-Haversian canals. The repeated measures design was utilized to remove individual variation and specifically look at the differences between the population for mean osteon number, mean fragment number and mean percentage of circumferential lamellar bone across the four fields (anterior, medial, posterior, and lateral). The ANOVA repeated measures model used was the mixed model, which allows for the use of both fixed effects (examples include gender or in this case bone type) and random effects (which include location within the bone, as there are an infinite number of places on the bone 47 that could have been selected). Within the mixed model design, the random effects would then be analyzed to determine their effect on the variance, while taking into account the fixed effects and their contribution (if any) to variance (Madrigal, 1998 and Bailey, 1995). The means for each quantification category (osteon number, fragment number and percentage of circumferential lamellae) were examined independently across the four fields using the entire population. The criterion of α=0.05 was used in these analyses to determine significance of difference. When significant differences were found for the means at individual orientation areas, a post hoc test was performed to determine which segment(s) in particular were contributing to the overall significant differences for that field. The tests selected for this additional analysis was the Least Significant Difference (LSD) test, as it can control for constant alphas (in this case, α=0.05) across a number of multiple tests. This ensures that the p-value given for each test is a true p-value and not skewed due to the number of machinations that the LSD test goes through. 48 Chapter 5: Results The complete osteometric values for the uncut long bones of individuals A, B and C are listed in appendix A. The raw osteon, fragment, percent non-Haversian bone, and non-Haversian canal data collected after Kerley (1965) is presented by anterior, medial, posterior and lateral field size and is additionally grouped by segment (i.e., P1, M, D3) then bone (i.e., femur or tibia) and finally by individual (A, B or C) in spreadsheet format in Appendix B. The following figures illustrate the key results of the raw data. The raw data from each of the four Kerley fields for femur A is plotted for osteon count, fragment count and percent non-Haversian bone across individual A’s 25 shaft segments (P1-P12, M, D1-D12) in figures 24-26. Non-Haversian canals were not used in any of the figures as these were very rare throughout all three individuals, and thus were not a good indication of age differentiation throughout any of the long bones in this study. The graphs show an overlapping of values across the four fields, but when the anterior and posterior fields are removed from the plots (Figures 27-29), a very different picture arises. Figure 27 shows that the medial and lateral osteon values only overlap at one segment out of the 25 segments (P12). Figure 28 identifies only a minimal overlap of values for fragment number at D6 and D7. Figure 29 shows no overlap of values for percentage of non-Haverisan bone across the medial and lateral fields. In fact, the plot shows severe differences between the medial values (between 40% and 60%) and lateral values (between 2% and 5%). 49 70 60 Raw Osteon Counts 50 40 Anterior Medial Posterior Lateral 30 20 10 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 Segments Figure 24 : Raw Osteon Counts for Femur "A" Across Kerley's Four Fields 30 25 Raw Fragment Count 20 Anterior Medial Posterior Lateral 15 10 5 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 Segments Figure 25: Raw Fragment Counts for Femur "A" Across Kerley's Four Fields 50 70 60 Percent Non-Lamellar Bone 50 40 Anterior Medial Posterior Lateral 30 20 10 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 Segments Figure 26: Percentage of Non-Lamellar Bone for Femur "A" Across Kerley's Four Fields 60 50 Osteon Number 40 Medial Lateral 30 20 10 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 Segment Figure 27: Raw Osteon Counts for Femur "A" Across Medial and Lateral Fields 51 30 25 Fragment Number 20 Medial Lateral 15 10 5 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 Segment Figure 28: Raw Fragment Number for Femur "A" Across Medial and Lateral Fields 70 60 Percent Non-Haversian Bone 50 40 Medial Lateral 30 20 10 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 Segment Figure 29: Percent Non-Haversian Bone for Femur "A" Across Medial and Lateral Fields 52 This severe difference in values throughout two of the four positional fields within one segment is most likely the reason for using a sum of the values across the four Kerley fields to estimate age. The summed values across the four fields at each segment for osteon number, fragment number and percent non-Haversian bone were placed into the appropriate regression equations for femur, tibia and fibula. A mean value was obtained as well as, an age range which included the addition and subtraction of the standard error for the estimate. The mean values (square) and age range (bar) was plotted for each segment based on summed osteon number, summed fragment number and average percent non-Haversian bone for each femur, tibia and fibula (Figures 30-56). Figures 30-38 represent age estimates for individual A. This individual was actually 50 years old at the time of death. Figures 39-47 display age estimates for individual B, with an actual age at death of 17 years old. Figures 48-56 enumerate the age estimates for individual C, who was 60 years old at the time of death. Figure 57 shows the summed value of osteon number at each segment of femur A, plotted against the summed value of fragment number at each segment of femur A as well as the average of these two sums at each segment of femur A. Since it has been determined that the age estimates from the summed osteon number and the summed fragment number most closely estimate age when using the Kerley method (Stout and Gelhert 1982), the osteon ages and the fragment ages were averaged at each section and estimates for each of the three pelvic limb elements. These estimates were then plotted on one graph for each individual (Figures 58-60). 53 160 140 120 Age (Years) 100 80 60 40 20 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 P7 P8 P9 P10 P11 P12 Sections Figure 30: Age Estimates (Osteons) for Femur (A) 100 90 80 70 Age (Years) 60 50 40 30 20 10 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 Sections Figure 31: Age Estimates (Fragments) for Femur (A) 54 90 80 70 Age (Years) 60 50 40 30 20 10 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 Sections Figure 32: Age Estimates (% Non-Haversian) for Femur (A) 160 140 120 Age (Years) 100 80 60 40 20 0 D9 D6 D3 M P3 Sections Figure 33: Age Estimates (Osteons) for Tibia (A) 55 P6 P9 90 80 70 Age (Years) 60 50 40 30 20 10 0 D9 D6 D3 M P3 P6 P9 Sections Figure 34: Age Estimates (Fragments) for Tibia (A) 90 80 70 Age (Years) 60 50 40 30 20 10 0 D9 D6 D3 M P3 P6 Sections Figure 35: Age Estimates (% Non-Haversian) for Tibia (A) 56 P9 160 140 120 Age (Years) 100 80 60 40 20 0 D12 D9 D6 D3 M P3 P6 P9 P6 P9 Sections Figure 36: Age Estimates (Osteons) for Fibula (A) 80 70 60 Age (Years) 50 40 30 20 10 0 D12 D9 D6 D3 M P3 Sections Figure 37: Age Estimates (Fragments) for Fibula (A) 57 140 120 100 80 60 40 20 0 D12 D9 D6 D3 M P3 P6 P9 Figure 38: Age Estimates (% Non-Haversian) for Fibula (A) 100 90 80 70 Age (Years) 60 50 40 30 20 10 0 D9 D6 D3 M P3 Sections Figure 39: Age Estimates (Osteons) for Femur (B) 58 P6 P9 40 35 30 Age (Years) 25 20 15 10 5 0 D9 D6 D3 M P3 P6 P9 Sections Figure 40: Age Estimates (Fragments) for Femur (B) 80 70 60 Age (Years) 50 40 30 20 10 0 D9 D6 D3 M P3 P6 Sections Figure 41: Age Estimates (% Non-Haversian) for Femur (B) 59 P9 90 80 70 Age (Years) 60 50 40 30 20 10 0 D9 D6 D3 M P3 P6 P9 P6 P9 Sections Figure 42: Age Estimates (Osteons) for Tibia (B) 30 20 Age (Years) 10 0 D9 D6 D3 M P3 -10 -20 -30 Sections Figure 43: Age Estimates (Fragments) for Tibia (B) 60 70 60 Age (Years) 50 40 30 20 10 0 D9 D6 D3 M P3 P6 P9 Sections Figure 44: Age Estimates (% Non-Haversian) for Tibia (B) 70 60 Age (Years) 50 40 30 20 10 0 D12 D9 D6 D3 M P3 P6 Sections Figure 45: Age Estimates (Osteons) for Fibula (B) 61 P9 P12 35 30 25 Age (Years) 20 15 10 5 0 D12 D9 D6 D3 M P3 P6 P9 P12 -5 -10 Sections Figure 46: Age Estimates (Fragments) for Fibula (B) 140 120 Age (Years) 100 80 60 40 20 0 D12 D9 D6 D3 M P3 P6 Sections Figure 47: Age Estimates (% Non-Haversian) for Fibula (B) 62 P9 P12 180 160 140 Age (Years) 120 100 80 60 40 20 0 P12 P9 P6 P3 M D3 D6 D9 Sections Figure 48: Age Estimates (Osteons) for Femur (C) 80 70 60 Age (Years) 50 40 30 20 10 0 P12 P9 P6 P3 M D3 Sections Figure 49: Age Estimates (Fragments) for Femur (C) 63 D6 D9 90 80 70 Age (Years) 60 50 40 30 20 10 0 P12 P9 P6 P3 M D3 D6 D9 Sections Figure 50: Age Estimates (% Non-Haversian) For Femur (C) 140 120 Age (Years) 100 80 60 40 20 0 P9 P6 P3 M D3 Sections Figure 51: Age Estimates (Osteons) for Tibia (C) 64 D6 D9 80 70 60 Age (Years) 50 40 30 20 10 0 P9 P6 P3 M D3 D6 D9 Sections Figure 52: Age Estimates (Fragments) for Tibia (C) 100 90 80 70 Age (Years) 60 50 40 30 20 10 0 P9 P6 P3 M D3 D6 Sections Figure 53: Age Estimates (% Non-Haversian) for Tibia (C) 65 D9 100 90 80 70 Age (Years) 60 50 40 30 20 10 0 P9 P6 P3 M D3 D6 D9 D6 D9 Sections Figure 54: Age Estimates (Osteons) for Fibula (C) 50 45 40 35 Age (Years) 30 25 20 15 10 5 0 P9 P6 P3 M D3 Sections Figure 55: Age Estimates (Fragments) for Fibula (C) 66 90 80 70 Age (Years) 60 50 40 30 20 10 0 P9 P6 P3 M D3 D6 D9 Sections Figure 56: Age Estimates (% Non-Haversian) for Fibula (C) 140 120 Age (Years) 100 80 Average Osteon Fragment 60 40 20 0 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 Sections Figure 57: Mean Age Predictions For Femur (A) 67 120 100 Age (Years) 80 Femur Tibia Fibula 60 40 20 0 D9 D6 D3 M P3 P6 P9 Segments Figure 58: Average Age Estimations (Individual A) 60 50 Age (Years) 40 Femur TIbia Fibula 30 20 10 0 D9 D6 D3 M Sections P3 P6 Figure 59: Average Age Estimations (Individual B) 68 P9 100 90 80 70 Age (Years) 60 Femur Tibia Fibula 50 40 30 20 10 0 P9 P6 P3 M D3 D6 D9 Sections Figure 60: Average Age Estimations (Individual C) A factorial ANOVA was performed on femur A to determine whether the summed osteon number, summed fragment number and average percent of nonHaversian bone were significantly different from segment to segment. The summary data is presented in Table 1. The results indicate that osteon number and fragment number are not significantly different from segment to segment in Femur A, suggesting that it is not necessary to sample at one centimeter increments. Hence, three centimeter increments account for enough of the variation throughout the shaft. Percentage of non-Haversian bone, however, does differ significantly from segment to segment of femur A. Further post hoc statistics were run to determine where this significant difference was located throughout the shaft. These statistics are presented in Table 2. 69 Table 1: Factorial ANOVA Summary for Femur A Comparison F-Value p-Value Osteon Count by Segment 1.10 0.3628 Fragment Number by Segment 1.04 0.4296 % Non-Haversian Bone by Segment 1.75 0.0350* Table 2: Post Hoc Summary for Percent Non-Haversian Bone Segment Comparison t-Value p-Value D1-D11 -2.69 0.0089 D1-D12 -1.86 0.0674 D3-P6 -2.10 0.0391 D9-P6 -2.30 0.0245 D9-P12 -2.15 0.0349 D10-D11 -2.93 0.0045 D10-D12 -2.10 0.0391 D11-D2 3.57 0.0006 D11-D3 3.71 0.0004 D11-D4 3.57 0.0006 D11-D5 2.59 0.0116 D11-D6 3.32 0.0014 D11-D7 3.22 0.0019 D11-D8 3.32 0.0014 D11-D9 3.91 0.0002 D11-M 3.57 0.0006 D11-P1 2.93 0.0045 D11-P2 2.83 0.0059 D11-P3 3.17 0.0022 D11-P5 3.32 0.0014 D11-P7 2.74 0.0078 D11-P8 3.47 0.0009 D11-P10 2.34 0.0217 D11-P11 2.54 0.0132 D12-D2 2.74 0.0078 D12-D3 2.88 0.0052 70 Table 2 (Continued) Segment Comparison t-Value p-Value D12-D4 2.74 0.0078 D12-D6 2.49 0.0150 D12-D7 2.39 0.0192 D12-D8 2.49 0.0150 D12-D9 3.08 0.0029 D12-M 2.74 0.0078 D12-P1 2.10 0.0391 D12-P2 2.00 0.0488 D12-P3 2.34 0.0217 D12-P4 2.10 0.0391 D12-P5 2.49 0.0150 D12-P8 2.64 0.0101 Repeated measures ANOVA analysis tested the significance of osteon number (Table 3), fragment number (Table 4) and percent non-Haversian bone (Table 5) across all segments of each long bone at a specific directional position (anterior, medial, posterior and lateral). Significance was based on an alpha of 0.05. Only the posterior and lateral radius, anterior ulna, lateral femur and lateral tibia showed a significant difference for osteon count. The ulna and fibula showed a significant differences for fragment count. There were significant differences seen in humerus, ulna and fibula for percent of non-Haversian bone. If a value was found to be significant at the 0.05 level, a series of post hoc evaluations including least squared means model was used to identify the contributing factors to significance. The post hoc statistics are summarized in Tables 6-15. 71 Table 3: Repeated Measures ANOVA Summary for Osteon Count Bone/Position F-Value p-Value Humerus/ Anterior 0.68 0.6719 Humerus/ Medial 1.75 0.1999 Humerus/ Posterior 0.23 0.9595 Humerus/Lateral 0.55 0.7631 Radius/Anterior 0.56 0.7309 Radius/Medial 1.45 0.3709 Radius/Posterior 9.76 0.0232* Radius/Lateral 8.95 0.0271* Ulna/Anterior 5.76 0.0225* Ulna/Medial 1.26 0.3689 Ulna/Posterior 1.21 0.3871 Ulna/Lateral 0.88 0.5216 Femur/Anterior 0.42 0.8510 Femur/Medial 0.35 0.8949 Femur/Posterior 0.41 0.8569 Femur/Lateral 3.08 0.0462* Tibia/Anterior 1.61 0.2263 Tibia/Medial 1.36 0.3060 Tibia/Posterior 1.28 0.3362 Tibia/Lateral 5.42 0.0064* Fibula/Anterior 0.49 0.8039 Fibula/Medial 1.85 0.1716 Fibula/Posterior 1.10 0.4184 Fibula/Lateral 1.41 0.2869 72 Table 4: Repeated Measures ANOVA Summary for Fragment Count Bone/Position F-Value p-Value Humerus 1.99 0.0779 Radius 1.36 0.2615 Ulna 5.35 0.0012* Femur 0.41 0.8691 Tibia 0.16 0.9873 Fibula 2.34 0.0398* Table 5: Repeated Measures ANOVA Summary for Percent Non-Haversian Bone Bone/Position F-Value p-Value Humerus 2.49 0.0302* Radius 1.42 0.2387 Ulna 6.40 0.0003* Femur 1.10 0.3729 Tibia 0.43 0.8547 Fibula 5.66 <0.001* Table 6: Differences of Least Square Means for Posterior Radius (Osteon Count) Segment Comparison t-Value p-Value D3-P3 2.65 0.0572 D3-P6 6.43 0.0030 D3-P9 3.01 0.0397 D6-P6 4.91 0.0080 M-P6 4.91 0.0080 P3-P6 3.78 0.0194 73 Table 7: Differences of Least Square Means for Lateral Radius (Osteon Count) Segment Comparison t-Value p-Value D3-D6 5.20 0.0065 D3-M 4.29 0.0127 D3-P3 4.29 0.0127 D3-P6 6.10 0.0037 Table 8: Differences of Least Square Means for Anterior Ulna (Osteon Count) Segment Comparison t-Value p-Value D3-P3 -2.74 0.0289 D6-P3 -4.76 0.0021 M-P3 -2.60 0.0356 P3-P6 2.60 0.0353 Table 9: Differences of Least Square Means for Lateral Femur(Osteon Count) Segment Comparison t-Value p-Value D3-M -2.30 0.0400 D3-P3 -2.37 0.0351 D3-P6 -2.95 0.0121 D3-P9 -3.02 0.0106 D9-P6 -2.66 0.0207 D9-P9 -2.73 0.0181 74 Table 10: Differences of Least Square Means for Lateral Tibia (Osteon Count) Segment Comparison t-Value p-Value D3-P6 -2.39 0.0343 D3-M 2.73 0.0183 D6-D9 3.58 0.0038 D6-M 5.12 0.0003 D6-P3 3.58 0.0038 D6-P6 2.90 0.0133 D6-P9 4.35 0.0009 M-P6 -2.22 0.0466 Table 11: Differences of Least Square Means for Ulna (Fragment Count) Segment Comparison t-Value p-Value D3-M -2.79 0.0075 D3-P3 -3.72 0.0005 D6-M -2.19 0.0333 D6-P3 -3.12 0.0030 M-P6 2.28 0.0272 P3-P6 3.09 0.0033 Table 12: Differences of Least Square Means for Fibula (Fragment Count) Segment Comparison t-Value p-Value D6-P9 -2.03 0.0460 D9-P6 -2.77 0.0071 D9-P9 -3.01 0.0035 M-P6 -2.03 0.0460 M-P9 -2.28 0.0258 75 Table 13: Differences of Least Square Means for Humerus (Percent Non-Haversian) Segment Comparison t-Value p-Value D3-M 1.77 0.0804 D6-M 2.47 0.0160 D6-P3 2.28 0.0258 D9-M 2.20 0.0310 D9-P3 2.03 0.0457 D9-P6 2.37 0.0203 Table 14: Differences of Least Square Means for Ulna (Percent Non-Haversian) Segment Comparison t-Value p-Value D3-P3 2.92 0.0053 D3-P6 2.84 0.0065 D6-M 2.40 0.0204 D6-P3 4.14 0.0001 D6-P6 3.94 0.0003 Table 15: Differences of Least Square Means for Fibula (Percent Non-Haversian) Segment Comparison t-Value p-Value D3-D6 -2.56 0.0124 D3-D9 -2.04 0.0452 D6-P3 2.94 0.0043 D6-P6 3.80 0.0003 D6-P9 4.50 <0.0001 D9-P3 2.42 0.0180 D9-P6 3.27 0.0016 D9-P9 3.97 0.0002 M-P6 2.52 0.0140 M-P9 3.21 0.0019 76 Chapter 6: Discussion The results of this research present a number of specific conclusions about the ability to utilize any part of the shaft of a specific long bone with specific aging methods. Based on the picture painted by plotting raw counts of osteon number, fragment number and percent of non-Haversian bone, it is obvious that these values differ greatly from anterior, medial, posterior and lateral positions within the same bone (see Figures 24-29). Actually, the difference between medial and lateral values at the same segment of the same bone is so great that their corresponding lines on the graph rarely overlap, if they overlap at all. Given this, fragmentary remains will be very hard to age even within the same bones. To adjust for this severe difference the Kerley method uses sums of values across the four fields. This “averaging” can reduce the effect that the differentiation between positions has on the age estimate, but it may also give a false picture of the lack of significant difference throughout the shaft (see Table 1). This is what is noted in the factorial ANOVA which indicates the lack of significance in summed or averaged values of the four fields across each segment throughout the shaft. When looking at the age estimates derived from the specific regression equations (see Figures 30-56), there is much more differentiation shown throughout the shaft for each age estimate. This suggests that if the age estimate is made on areas other than the midshaft there is a higher probability that age estimate will be significantly different than the estimate at midshaft. The accuracy of these estimates differs according to bone and quatification category. For example, individual A was 77 50 years old at the time of death, yet very few of the prediction equations gave an age of 50 years within the range of the estimation. None of the segments of femur A included the age of 50 in the age range based solely on osteon number. Ten of the twenty-five segments of femur A included 50 in the age range for fragments. The best quatification category for femur A was the percent non-Haversian bone, where 22 of 25 segments included 50 years in the age range. The tibia for individual A showed a similar pattern. None of the 7 segments of tibia A included 50 years in the age range using only osteon number. Only 2 of 7 segments (D9 and D6) included 50 years in the age range based on fragments, while 5 of 7 segments included 50 years in the age range based on percent non-Haversian bone. Individual B was a much younger individual (17 years old at death). This was evident by the difficulty the regression equations had isolating the age of this individual. None of the femoral and tibial osteon estimations included 17 years in the range. Only one of the fibular osteon estimations included 17 years old and that was the most distal segment of the bone (D12). Tibial and fibular fragment estimates each had only two segments that included the correct age. In fact, each of the other estimates given for the tibial segments based on fragments included negative ages in the range of the estimate. Six of seven femoral fragments included 17 years in the age estimate. The percentage of non-Haversian bone provided little help for femur and tibia which each had only one segment that included the appropriate age. Five of the nine fibular segments included 17 years in the age estimates for percent of nonHaversian bone (all distal segments). 78 Individual C was another older individual (60 years of age at death) which again posed a problem for the Kerley equations. None of the femoral or fibular segments included 60 years of age in the estimate based on osteons and only one of the tibial segments gave an appropriate age range. In fact, all of the femoral and fibular estimates severely overaged this individual by as much as double the original age. None of the tibial and fibular segments included 60 years in the age range based on fragment number, while half of the femoral segments included the appropriate age in the range. All of the fibular segments underaged this individual based on fragment number. Age estimates based on percentage of non-Haversian bone seemed to better estimate the age of this individual, as all of the femoral segments and 7 of 8 tibial segments included the appropriate age. Only two of the seven fibular segments estimated the age of this individual correctly based on the percent of non-Haversian bone, all other segments underaged this individual. Taking into account this summary of the results as well as the information presented in the age estimate graphs (Figures 57-60), it is clear that the Kerley method was hard pressed to accurately estimate the age of the individuals in this research even when averaging the osteon and fragment age estimates as suggested by Stout and Gehlert (1982). This may be due to the fact that these three individuals represent the absolute ends of the age spectrum and beyond what Kerley’s method is based on. Since most of his data was derived from military casualties between 20 and 40 years of age, his method is from a much different aged population than the individuals aged in this study. This said, it does not imply that this method should not 79 have been used for this study, instead it reiterates that these are merely estimates and that one must know the limitations of the aging methods before they are used. The statistical analysis shows the differentiation within and between the elements of the skeleton more clearly based on each quantification category (Tables 3-5). It indicates that based on osteon count, the humerus and the fibula have no significant differences throughout the shaft. Each of the other long bones has at least one position which shows a significant difference in the ostoen number throughout the segments. The posterior and lateral radius show significant differences between the proximal and distal portions of the bone. This may well be an effect of the functional morphology of the bone at these locations. The proximal end of the posterior and lateral radius is the site of the supinator and pronator teres muscle attachements, that rotate and flex the hand, while the distal end of the radius has no such attachments acting upon it. Similarly the anterior and medial radius are completely covered (proximal to distal) by muscle attachments (flexor pollicis longus, that flexes the thumb, and the pronator quadratus, which turns the wrist) which are equally pulling on these surface of the bone. The anterior ulna is completely covered by the flexor digitorum profundus, which flex the digits, which may account for its significiance. The lateral tibia shows severe significant differences between the proximal and distal end. Morphologically, this may be explained simply by the attachment of the tibialis anterior and tibialis posterior muscles that both elevate the foot separated by the interosseous membrane and ligament that attaches proximally. No such muscle attachment is found at the distal portion of the lateral tibia. These muscle attachment sites may account for a great deal 80 of the micromorpholoigcal differentiation throughout the bone due to the mechanical stress and strain placed on the bone by the action of the muscle. The more a muscle pulls and modifies on a section of bone, the more that area is susceptible to acute or chronic microfractures and thus would be in need of bone repair and remodeling. Areas that do not have such a high stress load may not undergo remodeling at the same rate. The main caveat of thinking about these functional demands should heavily caution anyone looking to apply a blanket aging method for any portion of the shaft of a long bone, not to mention, disable the notion that all of the long bones are similar in terms of micromorphology. Given the results of this research, it is imperative that future research take the following into consideration: 1.) While much attention has been paid to the pelvic limb, very little is understood about the pectoral limb and the change in these elements as the skeleton ages. Biomechanically, less stressed bones will remodel less and may give a more clear look at actual microstructural changes due to age of the bone as opposed to repair of the bone due to stress. Since the pectoral limb elements do not undergo the same mechanical stress as the pelvic limb elements do, it is possible that the humerus, radius and ulna may give better age estimations than the highly stressed femur, tibia and fibula. 2). The data from this research indicates that the humerus and fibula are best at age estimation of the individuals in this research. More focus should be placed on older and younger individuals in future studies to identify if these less mechanically 81 stressed bones are more accurate at aging across the age spectrum as well as the old and the young. 3) Biomechanical stress and strain are often reviewed at the macroscopic level in anthropology, though little has been done at the microscopic level. It is imperative that we understand what effect stress and strain caused by habitual action, obesity, biomechanical loading, and other mechanical stresses have on human bone at the microscopic level. It seems that our focus is at the macromorphological level and only when the bone fails under stress. What happens before the bone fails and how does the micromorphology accommodate these pressures? What effect do specific cultural and social practices and habits have on the bone at the microscopic level? 4) From the differentiation found within one segment between the anterior, medial, posterior and lateral positions it is clear that it may be very difficult to age fragmentary remains when no gross anatomical landmarks are available. This begs the question: Is there a way to take any fragment of bone and give a reasonable age estimate? While the current methodology may not allow us to answer this question there must be micro and macroscopic evidence of age even on small fragments of bone as it is a living entity which grows and changes throughout the human life cycle. Other avenues of inquiry must be identified to establish a method of age estimation of fragmentary human remains. These avenues may include but are not limited to biochemical signatures of bone, microstructural metrics (measurement of the microstructures like osteons, fragments, Haversian canals or lacunae), micromorphological population quantification and natural diagenic process of bone. 82 A plethora of questions still exist about human bone at the microscopic level. It is clear that if one were to focus on nothing other than bone micromorphology for an entire career one would still be left with more questions than s/he started with. This is the nature of an ever changing facet of humankind that we only understand on a cursory level. 83 Chapter 7: Conclusions For any histological evaluation of bone to be successful, we must understand cortical variation throughout the skeleton. Concomitantly, we must understand all current methods of histological analysis, including the specific variables and criterion which are required to use the method. Until we ascend to these heights, it must not be assumed that fragments contain similar histomorphology throughout the bones of the skeleton, let alone within one bone. This research has demonstrated that the Kerley Method should only be used to age a femur, tibia or fibula at midshaft as the variation throughout the shaft of these structures will introduce error into the age estimate. In developing new methods to analyze fragments, the results of this study must be taken into account. It demonstrates that the femur exhibits the greatest microstructural variation, based on Kerley’s four quantification categories, followed closely by the tibia and radius. The humerus, ulna and fibula have less within-bone variation for each of Kerley’s criteria. This incongruent nature of this histological design of the long bones within the skeleton suggest that with the criterion used for this study it may be impossible to come up with a all encompassing fragmentary aging technique. This does not suggest however that one or more of these criteria could not be used in conjunction with other variables to identify a method for the age estimation of highly fragmentary remains. At present, sanctions against destructive analysis prohibit even a fundamental understanding of intra- and inter-bone and intra-skeletal variation. This is unfortunate. Even though this sample is small, one major goal of this study was to histologically 84 demonstrate diaphyseal variation in both inter- and intra-skeletal elements. Using current histological aging techniques requires knowledge of the fragment’s origin as well as a detailed knowledge of the technique itself. It would not be prudent to employ a stature regression equation from a population not represented the specific victim to estimate his/her stature. Similarly, one would not age a female pubis using male standards. In light of this research, it is equally erroneous to apply midshaft aging techniques and equations carte blanche to each and every long bone fragment. Because of the impracticality of DNA examination for each fragment due to economic prohibitions, fragment size or risk of specimen loss due to the total destructive nature of this analysis, there is a promising future for the continued development of mineralized tissue techniques in forensic anthropology. To this end there are three long term goals within physical anthropology that must be achieved: First, it is necessary for educators to dispel the notion that an expertise is mineralized tissue histology (whether dental or osseous) is worthless and/or impossible to obtain. Moreover, there should be training readily available (or at least a knowledge of how to acquire specific training) for students with an interest in this growing subspecialty. Second, we need to obliterate the notion that destructive analysis destroys information. The histological perspective gained here and in future analyses provides far more information about human skeletal variation than poorly curated, underused, or fractured bones and teeth from teaching collections. 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Forensic Sci Int 22:203-211. Warwick R and Williams P (1973) Gray’s Anatomy. Philadelphia, WB Saunders. Wood J Milner G, Harpending H, and Weiss K (1992) The osteological paradox.. Current Anthropology 33:343-370. Yang YJ and Damron T (2002) Histology of Bone. e-Medicine. 19 August, 2002. eMedicine.com. 1 March 2005 http://www.emedicine.com/orthoped/ topic403.htm 91 Yoshino M, Imaizumi K, Miyasaka S, and Seta S (1994) Histological estimation of age at death using microradiographs of humeral compact bone. Forensic Sci Int 64:191-198 92 Appendices 93 Appendix A: Osteometric Measurements of Individuals A, B, and C 94 Individual A Humerus: Max. Length Epi. Breadth Max. V. Head Dia. Max. Dia. Mdsht. Min. Dia. Mdsht. Radius: Max. Length Sag. Dia. Mdsht. Trans. Dia. Mdsht. Ulna: Max. Length Dorsovolar Dia. Trans. Dia. Physiological Len. Min. Circum. Femur: Max. Length Bicond. Length Epicond. Length Max. Dia. of Head AP Subtroch. Dia. Tran. Subtroch. Dia. AP Dia. Mdsht. Trans. Dia. Mdsht. Circum. at Mdsht. Tibia: Cond-Mall. Length Max. Prox. Epi. Br. Max. Dist. Epi. Br. Max. Dia. Nutr. For. Tran. Dia. Nutr. For. Circ. at Nutr. For. Fibula: Max. Length Max. Dia. Mdsht. Individual B Individual C 306 60 46 21 15 312 66 45 23 19 330 67 48 23 22 239 11 12 238 12 15 256 12 15 254 15 11 226 35 254 15 14 228 40 275 18 12 240 36 446 444 77 47 26 30 425 422 88 43 22 32 470 468 89 46 27 33 29 23 89 24 26 85 29 28 95 353 74 51 35 369 80 56 32 391 83 54 37 22 28 23 95 101 100 342 10 360 14 391 16 95 Appendix B: Raw Data for Kerley’s Four Quantification Categories Key: A= Anterior M= Medial P=Posterior L=Lateral O=Osteon F=Fragment %=Percent Non-Haversian Bone NH=Non-Haversian Canals 96 Catalogue Number HS-A-1-D6 HS-A-1-D3 HS-A-1-M HS-A-1-P3 HS-A-1-P6 HS-A-1-P9 HS-A-3-D6 HS-A-3-D3 HS-A-3-M HS-A-3-P3 HS-A-4-D12 HS-A-4-D11 HS-A-4-D10 HS-A-4-D9 HS-A-4-D8 HS-A-4-D7 HS-A-4-D6 HS-A-4-D5 HS-A-4-D4 HS-A-4-D3 HS-A-4-D2 HS-A-4-D1 HS-A-4-M HS-A-4-P1 HS-A-4-P2 HS-A-4-P3 HS-A-4-P4 HS-A-4-P5 HS-A-4-P6 HS-A-4-P7 HS-A-4-P8 HS-A-4-P9 HS-A-4-P10 HS-A-4-P11 HS-A-4-P12 HS-A-5-D9 HS-A-5-D6 HS-A-5-D3 HS-A-5-M HS-A-5-P3 HS-A-5-P6 HS-A-5-P9 Letter A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Bone L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Ulna L. Ulna L. Ulna L. Ulna L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia AO 52 52 50 52 49 35 22 39 44 55 35 31 38 51 53 42 47 43 40 48 50 41 41 55 49 44 59 50 50 46 54 39 46 43 38 45 55 45 62 46 46 20 Seg D6 D3 M P3 P6 P9 D6 D3 M P3 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12 D9 D6 D3 M P3 P6 P9 97 AF 13 23 7 11 9 6 11 13 16 15 8 7 18 21 27 10 18 14 21 13 11 13 28 18 23 17 7 15 13 15 19 14 9 15 16 15 13 14 7 11 9 18 A% 15 5 2 5 5 2 30 40 15 10 25 40 15 2 10 15 2 2 5 2 5 15 2 10 2 5 10 10 5 2 5 20 15 20 10 2 2 25 40 10 10 10 ANH 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 MO 50 59 57 48 33 37 30 46 44 48 35 32 24 38 36 31 38 33 34 33 38 44 44 41 37 34 41 28 31 42 44 31 38 44 48 44 60 58 41 60 47 49 MF 6 16 17 13 12 6 7 9 9 19 13 11 13 15 11 10 12 10 14 12 12 12 7 5 11 6 7 6 8 4 11 2 9 7 12 10 7 11 14 16 19 11 M% 20 5 2 15 5 10 60 30 20 2 15 25 15 20 40 25 40 40 40 40 40 25 40 40 40 40 40 50 50 50 50 60 50 30 10 5 40 5 30 2 20 5 MNH 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 Catalogue Number HS-A-6-D12 HS-A-6-D9 HS-A-6-D6 HS-A-6-D3 HS-A-6-M HS-A-6-P3 HS-A-6-P6 HS-A-6-P9 HS-B-1-P9 HS-B-1-P6 HS-B-1-P3 HS-B-1-M HS-B-1-D3 HS-B-1-D6 HS-B-1-D9 HS-B-2-P9 HS-B-2-P6 HS-B-2-P3 HS-B-2-M HS-B-2-D3 HS-B-2-D6 HS-B-3-P6 HS-B-3-P3 HS-B-3-M HS-B-3-D3 HS-B-3-D6 HS-B-4-D9 HS-B-4-D6 HS-B-4-D3 HS-B-4-M HS-B-4-P3 HS-B-4-P6 HS-B-4-P9 HS-B-5-D9 HS-B-5-D6 HS-B-5-D3 HS-B-5-M HS-B-5-P3 HS-B-5-P6 HS-B-5-P9 HS-B-6-D12 HS-B-6-D9 HS-B-6-D6 Letter A A A A A A A A B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B Bone L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Radius L. Radius L. Radius L. Radius L. Radius L. Radius L. Ulna L. Ulna L. Ulna L. Ulna L. Ulna L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Fibula L. Fibula L. Fibula AO 1 53 51 51 47 43 40 46 30 31 26 44 32 40 34 30 21 28 33 30 24 25 35 17 23 22 21 27 12 24 26 30 27 30 33 24 34 29 30 32 19 27 19 Seg D12 D9 D6 D3 M P3 P6 P9 P9 P6 P3 M D3 D6 D9 P9 P6 P3 M D3 D6 P6 P3 M D3 D6 D9 D6 D3 M P3 P6 P9 D9 D6 D3 M P3 P6 P9 D12 D9 D6 98 AF 10 10 12 20 10 13 15 15 9 3 5 4 4 4 7 3 0 2 5 6 4 7 6 6 6 5 4 0 2 2 3 5 7 5 3 3 2 4 6 5 2 5 4 A% 2 15 2 2 15 2 2 2 20 2 5 2 2 5 5 2 2 5 10 10 5 2 20 25 10 20 30 50 60 10 10 10 2 15 5 2 2 2 5 2 40 5 10 ANH 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 7 0 0 0 0 0 0 0 0 0 0 0 0 0 0 MO 35 53 48 47 51 31 47 54 35 33 28 27 39 36 35 21 20 31 29 32 26 21 18 26 21 19 28 28 31 24 26 35 35 23 25 23 18 24 27 23 21 14 25 MF 9 13 12 15 11 12 19 20 6 4 3 3 2 4 6 2 5 4 4 6 8 4 9 6 3 2 5 4 4 3 6 7 2 8 0 0 0 0 0 4 4 9 6 M% 2 25 10 10 15 2 5 2 5 5 40 10 5 10 2 2 2 2 10 10 10 2 2 10 10 30 25 20 40 5 10 10 20 15 30 50 60 50 40 20 2 40 10 MNH 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 2 0 0 0 0 0 1 0 0 0 0 0 0 0 0 Catalogue Number HS-B-6-D3 HS-B-6-M HS-B-6-P3 HS-B-6-P6 HS-B-6-P9 HS-B-6-P12 HS-C-1-P9 HS-C-1-P6 HS-C-1-P3 HS-C-1-M HS-C-1-D3 HS-C-1-D6 HS-C-1-D9 HS-C-2-P6 HS-C-2-P3 HS-C-2-M HS-C-2-D3 HS-C-2-D6 HS-C-3-P6 HS-C-3-P3 HS-C-3-M HS-C-3-D3 HS-C-3-D6 HS-C-4-P12 HS-C-4-P9 HS-C-4-P6 HS-C-4-P3 HS-C-4-M HS-C-4-D3 HS-C-4-D6 HS-C-4-D9 HS-C-5-P9 HS-C-5-P6 HS-C-5-P3 HS-C-5-M HS-C-5-D3 HS-C-5-D6 HS-C-5-D9 Letter B B B B B B C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C Bone L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Radius L. Radius L. Radius L. Radius L. Radius L. Ulna L. Ulna L. Ulna L. Ulna L. Ulna L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia AO 23 24 26 31 29 23 39 49 43 28 36 42 50 37 35 39 35 43 26 39 32 29 19 43 41 37 38 41 36 28 31 46 27 45 57 48 47 39 Seg D3 M P3 P6 P9 P12 P9 P6 P3 M D3 D6 D9 P6 P3 M D3 D6 P6 P3 M D3 D6 P12 P9 P6 P3 M D3 D6 D9 P9 P6 P3 M D3 D6 D9 99 AF 7 4 5 5 6 7 9 9 9 7 9 9 15 9 12 13 9 12 1 12 13 8 8 17 12 15 13 12 13 5 4 10 9 10 9 11 14 9 A% 10 10 2 2 2 10 2 10 2 2 2 2 5 5 2 2 2 10 20 2 10 10 15 2 2 2 10 2 15 30 25 2 2 0 2 2 5 0 ANH 0 2 0 0 1 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 MO 19 16 21 25 31 25 29 39 42 32 46 47 43 32 26 42 48 44 30 37 31 41 34 57 48 45 47 54 49 42 44 35 28 33 47 52 49 37 MF 5 2 3 7 11 6 6 13 11 11 14 5 13 12 11 12 13 11 10 15 7 9 12 13 15 8 15 16 12 9 11 5 5 4 8 9 11 11 M% 10 40 10 2 2 25 5 2 5 2 2 2 2 2 2 2 2 5 2 5 20 25 10 2 2 2 2 2 2 5 2 10 10 25 2 2 5 2 MNH 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Catalogue Number HS-C-6-P9 HS-C-6-P6 HS-C-6-P3 HS-C-6-M HS-C-6-D3 HS-C-6-D6 HS-C-6-D9 Catalogue Number HS-A-1-D6 HS-A-1-D3 HS-A-1-M HS-A-1-P3 HS-A-1-P6 HS-A-1-P9 HS-A-3-D6 HS-A-3-D3 HS-A-3-M HS-A-3-P3 HS-A-4-D12 HS-A-4-D11 HS-A-4-D10 HS-A-4-D9 HS-A-4-D8 HS-A-4-D7 HS-A-4-D6 HS-A-4-D5 HS-A-4-D4 HS-A-4-D3 HS-A-4-D2 HS-A-4-D1 HS-A-4-M HS-A-4-P1 HS-A-4-P2 HS-A-4-P3 HS-A-4-P4 HS-A-4-P5 HS-A-4-P6 HS-A-4-P7 HS-A-4-P8 HS-A-4-P9 Letter C C C C C C C Letter A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Bone L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula Bone L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Ulna L. Ulna L. Ulna L. Ulna L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur Seg P9 P6 P3 M D3 D6 D9 Seg D6 D3 M P3 P6 P9 D6 D3 M P3 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 M P1 P2 P3 P4 P5 P6 P7 P8 P9 100 AO 50 46 43 36 27 33 28 AF 11 11 15 12 5 8 6 A% 2 2 2 10 15 30 15 ANH 0 0 0 0 0 0 3 MO 44 36 37 36 33 38 36 MF 12 10 16 9 10 15 7 M% 2 15 10 15 5 10 5 MNH 0 0 0 0 0 0 0 PO 51 50 46 49 54 41 42 52 57 50 35 37 31 39 34 40 32 31 47 52 52 47 43 47 50 45 45 39 32 41 34 29 PF 7 6 13 3 7 8 13 7 22 23 5 8 16 13 21 9 10 15 15 11 13 8 15 17 12 9 11 5 10 11 16 7 P% 10 10 10 5 2 2 30 5 2 2 40 40 10 2 2 2 10 25 2 2 2 10 5 10 20 10 10 2 40 20 2 20 PNH 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 LO 65 57 54 42 50 45 49 38 52 45 50 46 52 41 46 38 45 47 47 52 56 46 52 50 53 47 49 49 51 55 51 51 LF 7 13 20 9 10 8 14 12 21 18 20 19 20 26 24 8 11 14 21 18 15 18 21 20 20 25 20 17 21 24 19 21 L% 10 20 5 5 5 10 20 2 2 5 5 5 2 2 2 2 2 2 2 2 2 5 2 2 2 2 2 0 2 2 2 2 LNH 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Catalogue Number HS-A-4-P10 HS-A-4-P11 HS-A-4-P12 HS-A-5-D9 HS-A-5-D6 HS-A-5-D3 HS-A-5-M HS-A-5-P3 HS-A-5-P6 HS-A-5-P9 HS-A-6-D12 HS-A-6-D9 HS-A-6-D6 HS-A-6-D3 HS-A-6-M HS-A-6-P3 HS-A-6-P6 HS-A-6-P9 HS-B-1-P9 HS-B-1-P6 HS-B-1-P3 HS-B-1-M HS-B-1-D3 HS-B-1-D6 HS-B-1-D9 HS-B-2-P9 HS-B-2-P6 HS-B-2-P3 HS-B-2-M HS-B-2-D3 HS-B-2-D6 HS-B-3-P6 HS-B-3-P3 HS-B-3-M HS-B-3-D3 HS-B-3-D6 HS-B-4-D9 HS-B-4-D6 HS-B-4-D3 HS-B-4-M HS-B-4-P3 HS-B-4-P6 HS-B-4-P9 HS-B-5-D9 Letter A A A A A A A A A A A A A A A A A A B B B B B B B B B B B B B B B B B B B B B B B B B B Bone L. Femur L. Femur L. Femur L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Radius L. Radius L. Radius L. Radius L. Radius L. Radius L. Ulna L. Ulna L. Ulna L. Ulna L. Ulna L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Tibia Seg PO 50 49 36 47 37 61 62 57 49 47 26 41 54 51 57 49 57 43 38 26 32 32 25 18 22 25 21 28 28 30 27 16 22 20 18 25 33 26 26 33 31 40 34 30 P10 P11 P12 D9 D6 D3 M P3 P6 P9 D12 D9 D6 D3 M P3 P6 P9 P9 P6 P3 M D3 D6 D9 P9 P6 P3 M D3 D6 P6 P3 M D3 D6 D9 D6 D3 M P3 P6 P9 D9 101 PF 13 14 10 5 9 9 17 17 16 22 6 12 10 16 20 16 19 17 2 3 3 3 4 3 4 1 2 4 0 3 0 5 4 9 6 5 8 7 2 3 5 9 6 1 P% 15 10 40 40 50 25 2 5 2 5 20 10 2 2 2 5 2 2 5 2 2 10 20 40 50 40 50 2 30 10 30 2 5 2 2 10 10 20 30 50 20 5 10 40 PNH 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 0 LO 52 52 45 49 69 57 42 60 55 52 35 53 53 56 54 44 46 47 30 30 47 38 30 26 39 24 23 26 26 34 21 17 22 29 26 22 22 29 28 36 34 44 40 31 LF 16 12 27 14 11 16 17 14 18 9 10 7 13 9 17 15 20 13 3 3 2 3 4 4 5 4 4 6 8 7 4 3 5 7 4 4 4 9 4 5 4 6 5 3 L% 2 2 2 20 25 10 10 20 40 5 10 2 2 5 2 2 2 2 5 2 2 2 15 15 2 5 5 2 2 15 15 5 10 20 40 30 40 5 20 15 2 2 2 15 LNH 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 Catalogue Number HS-B-5-D3 HS-B-5-M HS-B-5-P3 HS-B-5-P6 HS-B-5-P9 HS-B-6-D12 HS-B-6-D9 HS-B-6-D6 HS-B-6-D3 HS-B-6-M HS-B-6-P3 HS-B-6-P6 HS-B-6-P9 HS-B-6-P12 HS-C-1-P9 HS-C-1-P6 HS-C-1-P3 HS-C-1-M HS-C-1-D3 HS-C-1-D6 HS-C-1-D9 HS-C-2-P6 HS-C-2-P3 HS-C-2-M HS-C-2-D3 HS-C-2-D6 HS-C-3-P6 HS-C-3-P3 HS-C-3-M HS-C-3-D3 HS-C-3-D6 HS-C-4-P12 HS-C-4-P9 HS-C-4-P6 HS-C-4-P3 HS-C-4-M HS-C-4-D3 HS-C-4-D6 HS-C-4-D9 HS-C-5-P9 HS-C-5-P6 HS-C-5-P3 HS-C-5-M HS-C-5-D3 Letter B B B B B B B B B B B B B B C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C Bone L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Fibula L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Hum L. Radius L. Radius L. Radius L. Radius L. Radius L. Ulna L. Ulna L. Ulna L. Ulna L. Ulna L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Femur L. Tibia L. Tibia L. Tibia L. Tibia L. Tibia Seg PO 30 28 31 24 20 4 17 15 22 16 22 12 25 22 44 35 34 35 39 39 54 34 37 40 42 41 34 37 42 30 33 53 46 41 34 45 42 41 34 31 25 36 34 39 D3 M P3 P6 P9 D12 D9 D6 D3 M P3 P6 P9 P12 P9 P6 P3 M D3 D6 D9 P6 P3 M D3 D6 P6 P3 M D3 D6 P12 P9 P6 P3 M D3 D6 D9 P9 P6 P3 M D3 102 PF 3 8 5 5 8 0 3 0 2 4 4 5 3 6 10 16 9 9 12 7 8 12 12 10 15 11 9 15 10 10 9 9 13 11 10 12 9 7 6 9 8 4 11 11 P% 10 2 2 10 20 70 20 40 25 25 25 5 2 25 2 2 5 2 2 2 2 2 2 2 2 20 2 2 25 30 20 2 2 2 2 10 5 10 2 5 10 2 2 5 PNH 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 LO 30 16 25 31 22 7 29 15 20 20 25 21 25 37 34 35 34 39 40 31 44 30 35 35 46 36 38 40 37 40 38 60 50 45 51 43 46 42 40 31 36 29 38 41 LF 0 0 0 2 3 0 7 5 13 3 3 5 16 9 4 15 8 10 5 5 7 12 14 12 14 14 11 11 12 9 15 15 16 14 22 11 14 15 4 4 8 10 9 9 L% 50 70 40 20 30 60 30 50 20 10 5 10 2 2 2 2 2 2 10 2 5 2 2 2 2 10 2 2 10 10 10 2 2 2 0 2 0 5 5 20 15 2 2 2 LNH 2 2 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Catalogue Number HS-C-5-D6 HS-C-5-D9 HS-C-6-P9 HS-C-6-P6 HS-C-6-P3 HS-C-6-M Letter C C C C C C Bone L. Tibia L. Tibia L. Fibula L. Fibula L. Fibula L. Fibula Seg PO 44 43 36 47 37 42 D6 D9 P9 P6 P3 M 103 PF 15 8 13 14 9 7 P% 2 15 5 2 10 20 PNH 0 0 0 0 0 0 LO 47 34 21 19 26 29 LF 15 11 5 8 5 6 L% 2 2 15 25 25 25 LNH 0 0 0 0 0 0 Vita Mariateresa Anne Tersigni was born on July 27, 1978 to Anthony and Flora Tersigni. She is the granddaughter of Andrea and Benedetta Tersigni and Mario and Maria Pelino. She is the sister of John and Andrea. She graduated from Regina High School in Harper Woods, Michigan in 1996. She attended Michigan State University, where she received a Bachelor of Science in Anthropology and a Bachelor of Science in Microbiology in May 2000. She was accepted to the Master’s program in the department of Anthropology at The University of Tennessee-Knoxville where she received her Masters of Arts in August 2002. She became a PhD student in physical Anthropology at The University of Tennessee-Knoxville in August 2002, and advanced to candidacy in December of 2003. She received her Doctorate of Philosophy in May of 2005. 104
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