Theoretical and methodological issues in paleopathology • 7 



Both bacterial (e.g. . Mycobacterium iitherculosis and Sio- 

 phylococciis aureus) and mycotic (lungai) infection should 

 be considered in differential diagnosis. Almost certainly the 

 proliferative lesions apparent on the vertebral arches would 

 not be seen in an x-ray film of a living patient. They thus 

 might not be part of the clinical understanding of skeletal 

 involvement in any of the diseases that could have produced 

 the lesions seen in this case. In view of this possibility one 

 needs to exercise caution in rejecting tuberculosis as a diag- 

 nostic option simply because of atypical, reactive bone for- 

 mation on some of the arches. This is particularly true in view 

 of diagnostic probabilities suggested by the high prevalence 

 of tuberculosis in England from the latter part of the medieval 

 period until the dramatic decline in this century. 



It is possible, of course, that the lesions were caused by 

 another bacterium such as Staphylococcus or by fungi, al- 

 though the latter disease is rare in recent medical history. The 

 crucial point is that the skeletal paleopathologist often sees 

 details of bone involvement in paleopathological cases that 

 include features not normally associated with modem clini- 

 cal cases. The existence of such lesions requires careful 

 thought and evaluation with the limitations of clinical experi- 

 ence being given appropriate consideration. 



The high prevalence of periosteal lesions on the tibia is 

 another example of a common observation in North Ameri- 

 can archeological skeletons that is rarely seen or noted in a 

 clinical context. Paleopathologists have difficulty in inter- 

 preting the significance of this condition, particularly in 

 cases where there are no additional lesions in other parts of 

 the skeleton. Trauma and infection are likely to be the most 

 common causes of such lesions. We are, however, unlikely to 

 differentiate a specific cause for many, if not most, cases of 

 this condition without further anatomical/histological stud- 

 ies in modem clinical cases. 



Close cooperation between paleopathology and clinical 

 medicine is an obvious and critical need in paleopathological 

 research. Research in skeletal paleopathology is now explor- 

 ing the diagnostic boundaries of clinical orthopedic disease. 

 We are starting to ask questions for which there is no obvious 

 clinical knowledge. Many of these questions are significant 

 for both research in paleopathology and an improved under- 

 standing of orthopedic pathology. Collaboration between the 

 paleopathologist and various medical specialists is likely to 

 provide a more complete picture of skeletal responses to 

 disease. 



Dr. Bruce Ragsdale, a pathologist with a specialty in 

 orthopedic diseases, and I are collaborating in studies of joint 

 disease, in an attempt to answer some of the questions raised 

 in paleopathological research (Figure 3). One important 

 question is, what are the soft tissues associated with some of 

 the lesions seen in joint diseases? Such research can be con- 

 ducted in some situations once the problem is defined, but 

 may be very difficult to do in conditions that rarely, if ever, 

 are brought to the attention of the clinician. 



Figure 3. Macerated proximal tibia from a modem case of 

 joint disease with a section through a lesion of the joint 

 surface removed before maceration. Clinical history, ante- 

 mortem and specimen x-ray films, and histological prepara- 

 tions of the section are being studied. 



Another illustration of the potentially productive relation- 

 ship that can exist between paleopathology and clinical medi- 

 cine is seen in the skeletal changes associated with the vari- 

 ous syndromes of inflammatory erosive joint disease. Ortner 

 and Utermohle (1981) published a case of polyarticular ero- 

 sive joint disease in a pre-Columbian female skeleton from 

 Kodiak Island, Alaska. The authors suggested that the most 

 likely syndrome for this case was rheumatoid arthritis. The 

 pattems of most lesions, as well as the distribution of os- 

 teoporosis, were major features supporting this opinion. The 

 problem with this diagnostic option is the extensive and se- 

 vere involvement of sacroiliac and spinal joints in the disease 

 process. 



Clinically, spinal and sacroiliac joint destmction is thought 

 to be rare in rheumatoid arthritis. The questions posed by this 

 case include: ( t ) how often is the spine and sacroiliac joint 

 involved in clinical cases of rheumatoid arthritis and (2) to 

 what extent is the failure to observe spinal and sacroiliac joint 

 involvement in rheumatoid arthritis an artifact of the limita- 

 tions of radiology? The answer to both of these questions is 

 important to both clinical medicine and paleopathology. 

 Since raising these questions, colleagues in rheumatology 

 have showed me two cases of rheumatoid arthritis that have 

 clear evidence of erosive changes in the sacroiliac joint. I 

 suspect that other parts of the spine are involved as well, but 

 such changes are not well known clinically because of the 

 limitations of radiological imaging. The significance is that a 

 paleopathological case raised diagnostic questions which re- 

 quired a second and more careful look at clinical cases. This 

 process has been a valuable experience for both the pal- 

 eopathologist and the clinician. 



Zagreb Paleopathology Symp. l9fiH 



