Anthropology

Allysha Winburn Dissertation Defense
Thursday, 6 July, 9:30am
Turlington 1208

Title:

Skeletal Age Estimation in Modern European-American Adults:  The Effects of Activity, Obesity, and Osteoarthritis on Age-Related Changes in the Acetabulum

Committee:

Chair:  Michael Warren
Members:  David Daegling and Ken Sassaman
External member:  Todd Manini (Institute on Aging)

Abstract:

In this dissertation, I investigated the nature of the progressive skeletal changes observed in the acetabulum (the pelvic component of the hip) to determine whether they are metamorphic or degenerative and ascertain whether they are useful for the estimation of age at death.
Changes in the acetabulum are poorly understood.  They may constitute skeletal metamorphoses, generally believed to be tightly linked with age.  Alternately, acetabular changes may represent skeletal degeneration (osteoarthritis or OA), generally believed to be affected by other factors in addition to age (e.g., obesity, physical activity).
I analyzed a sample of 409 female and male European-American skeletal individuals from the W.M. Bass Donated Skeletal Collection (University of Tennessee).  I observed and scored acetabular changes and OA, and I compared these data with documented demographic data (age, sex, body mass index, and habitual/occupational activities) for the 409 individuals.  I then tested for associations between acetabular changes and age, OA, activity, and obesity data.
Acetabular changes correlated strongly positively with both OA and age.  This indicates that the changes occurring in the joint are degenerative rather than metamorphic, but that they are still useful for age estimation.  Acetabular changes were relatively resistant to the effects of obesity and physical activity, also arguing for their relevance to studies of age.  In other joints, OA also showed strong positive correlations with age, weaker positive correlations with obesity, and no relationship with activity.  The disease likely has both biomechanical and systemic components.
In conclusion, the degenerative changes of the acetabulum are valid skeletal indicators of age.  The etiology of OA is multifactorial, but age is a major contributing factor.  The impact of physical activity is less straightforward than once thought, and it can even improve joint health.  Thus, anthropological assumptions about the correlation between activity and OA should be reevaluated, and weight loss and exercise should be considered palliative for both OA and obesity in a clinical context.  These findings have implications not only for the study and identification of the dead, but also for the improvement of health outcomes and interventions for the living.