The effects of orthopedic pathological conditions and systemic diseases on the prevalence of hip osteoarthritis in Modern African- and European-Americans.

Osteoarthritis (OA) is a leading cause of disability among aging adults. In the U.S., many individuals living with total hip replacements attribute OA as the cause. However, the majority of anthropological OA research excludes pathological individuals (i.e., individuals with systemic disease, traumatic injuries, or orthopedic devices). Thus, little is known about how implants and pathological conditions impact OA beyond a general acceptance that they likely increase OA risk. This study adds to the skeletal research surrounding OA by directly investigating its relationship with age, disease, and implants. The proximal femora of 186 African- and European-American individuals (21-95 years old) from the Edmonds Orthopedic Pathology Collection (National Museum of Health and Medicine; Armed Forces Institute of Pathology) were analyzed. The individuals were grouped into three cohorts: disease; non-disease; and previous injury/implant. Jurmain's (1990) ordinal scoring method was used to categorize OA changes as: none/slight; moderate; severe; and ankylosis. Intra-rater reliability for the scoring of OA was perfect, while inter-rater reliability was moderate. Results from Chi-square tests, exploratory data analysis, and ordinal logistic regression showed that there was a statistically significant relationship (p < 0.001) between degree of OA, age, recorded disease (e.g., cancer), and evidence of previous injury (i.e., healed fractures, fracture fixation devices). In contrast with the expectation that different populations exhibit different patterns of OA, no significant sex or ancestry effects were observed. These results help researchers better understand the etiology and contemporary risk factors of OA as well as identifying an additional subset of the population who may be at greater risk for developing OA - i.e., individuals with fractures, implants, and systemic disease, especially those in older age cohorts (60+ years).