In the discipline of medieval archaeology, particularly with respect to the understanding of the daily lives of the people, rather than the castles, cathedrals and monasteries which they have built, very little is as important as the detrimental biological forces they face. Although, certainly, life is not defined entirely by its hardships, comprehension of a discipline which focuses on a specifically detrimental variable in the lives of these people, such as the diseases they encounter most often, particularly those which can be analyzed through the work of an archaeologist, is invaluable to an accurate reconstruction of the lives of the people being studied. The supplementary knowledge provided by such a discipline by way of intricate scientific understanding of the diseases present, as well as how those diseases manifest themselves over gradations of sex, age, and cline, is integral, I contend, to the work of the medieval archaeologist. Following intricate description and analysis of the function of such diseases I will go into detail regarding the ways in which they have been found to manifest themselves in a medieval context along these axes of gradation, and will conclude with the more general patterns that can be teased from the great mess of variation inevitably present in all large-scale paleopathological studies. Prior to such discussion, however, a description and understanding of what the discipline of paleopathology is, and what it aims to understand, is in order.

The term ‘paleopathology’ has been used as far back as the 19th century to describe the general study of disease in the past. The major function it serves as a discipline is to analyze and describe the occurrence of particular diseases throughout time from the study of, primarily, human remains. It provides invaluable evidence regarding the ways in which these occurrences were distributed, expressed, and the frequency in which they occurred (Rogers & Dieppe, 1990; Brandt et al., 2003). Because it is so often the case that soft tissues are not adequately preserved, and in most instances not preserved at all, the paleopathologist has a distinct disadvantage in comparison to the modern physician. In spite of this limitation, however, the paleopathologist is also in a position of advantage over the physician; if an archaeological site possesses a complete abnormal skeleton the paleopathologist, unlike the physician with her living patient, is able to examine it in its entirety (Ortner, 2003). For the medieval archaeologist a thorough knowledge of paleopathology, or at the least hiring a paleopathologist to aid in analysis, is invaluable. For the latter, this information contributes to a more complete understanding of disease distribution over time; for the former, knowledge of the diseases with which the medieval people faced in their lifetimes aids in a more accurate reconstruction of the lives of these individuals. There are certainly many limitations to the research of these centuries-old skeletons with respect to diagnosis, both in material and methodology, however. What information the medieval archaeologist is able to tease out has a three-fold effect, it provides a more complete archaeological understanding of the lives of the individuals in the population, it contributes to the growing knowledge of the evolution of disease, and finally, via these last two effects, it enhances and complements current medical research as to the effects and possible origins of these diseases (Ortner, 2003).

With respect to the many abnormalities encountered by the paleopathologist in the archaeological environment, joint disease is that which is most frequently observed (Rogers & Dieppe, 1990; Brandt et al., 2003). As the material is entirely skeletal in most cases, this is not surprising. The research, therefore, of patterns of joint disease throughout the medieval period is the most extensive, and in many ways acts as a point of both comparison and transition for the modern paleopathologist and medieval archaeologist, respectively. As there is certainly no dearth of paleopathological and archaeological analysis regarding joint disease in medieval populations it is possible to gather a comprehensive understanding of the disease conditions with which the medieval people of Europe faced on a daily basis. These diseases are both debilitating and survivable, and as such analysis of the extent to which these diseases have effected the populations in question may reflect in a way the level of social care present. In order to gather a complete comprehension of the medieval environment in this respect, however, the form and function of these joint diseases must be understood. As such, what will follow is a discussion of the various joint diseases for which there are medieval cases: osteoarthritis, rheumatoid arthritis, and the not exclusively joint related bone disease, osteoporosis. From forming a basic understanding of how these diseases effect the human skeleton flows the foundation on which it is possible to accurately analyze and describe the relationship between joint and bone disease and the lives of the medieval persons effected.

Osteoarthritis (OA), also known as degenerative joint disease, is the most common form of arthritis in modern populations (Scott & Hochberg, 1998; Reginster, 1999). As a disorder of diverse etiologies, affecting both small and large joints, singly or in combination, OA diseases involve all of the tissues of the diarthroidal joint (e.g., temporomandibular joint): articular cartilage, subchondral bone, ligaments, joint capsule, synovial membrane, and periarticular muscles. Of these, three are major components of skeletal involvement in the pathology of osteoarthritis as outlined by Ortner (2003):

(1) breakdown of articular cartilage, which may result in bone on bone contact and abnormal abrasion of the subchondral bone, (2) reactive bone formation (sclerosis) both in the subchondral compact bone (eburnation) and in the trabeculae underlying the affected subchondral compact bone and possibly associated with cyst formation, and (3) new growth of cartilage and bone at the joint margins (osteophytes).

Figure 1: Articular cartilage, or hyaline cartilage as it is most often called, covers the joint surfaces in synovial joints.

Ultimately the articular cartilage (Figure 1), that which is most impacted by this disease, degenerates and there is full thickness loss of the joint surface, resulting in destabilization of the joint (Brandt et al., 2003). These components in most cases progress slowly over the life of the individual, and the diagnostic changes with respect to the archaeological record come as a direct result of the alterations of the articular cartilage (Ortner, 2003). Complete attrition of the articular cartilage leads to mechanical degradation and polishing of the exposed articular surface, known as eburnation, resembling that of porcelain, and is the most diagnostic means by which the archaeologist and paleopathologist may diagnose severe osteoarthritis in skeletal remains (Ortner, 2003). To accurately diagnose these medieval remains, however, the archaeologist must use all of the resources available. Radiographs are the standard criteria by which osteoarthritis is diagnosed, and as such many archaeologists take advantage of radiograph technology in the analysis of bioarchaeological assemblages.

In the medieval period, as is the case now, there are two general types of osteoarthritis (Figure 2) recognized: (1) primary osteoarthritis occurs later in life and is a result of the biomechanical stress and trauma incurred over the life of the individual, and (2) secondary arthritis, which develops early in life as a result of congenital abnormalities, such as a slipped femoral epiphysis (Ortner, 2003; Brandt et al., 2003). With respect to modern peoples, research demonstrates that in individuals over 15 years old the earliest and most often involved joint in the condition of osteoarthritis is the knee. As will be demonstrated, the case is not necessarily the same for peoples broadly, or within clinal gradation, in the medieval period. Overall, the distribution and severity of osteoarthritis varies between societies, with different gender and economic roles determining likelihood of severity (Ortner, 1968). Perhaps the biggest problem in the analysis and diagnosis of osteoarthritis in skeletal assemblages, however, is not these confounding variables but the methodology for quantifying the observed osteoarthritic degeneration (Ortner, 2003). Such analysis is beyond the scope of this paper, and as such it will be trusted that the archaeologists and paleopathologists cited herein utilized standard methods by which to formulate their conclusions.

Figure 2: This is marked OA of the left knee. Note the absence of space in the joint, the direct bone-bone contact.