Date of Award
Master of Arts
Richard L. Jantz
Lee Meadows Jantz, Michael H. Logan, William Seaver
The purpose of this study was two-fold: to examine secular change in the size of the knee joint during the last century in White males and females, and to compare the prevalence of knee osteoarthritis over the same time frame. In addition, a specific effort was made to determine a relationship between the modern rise in obesity and knee osteoarthritis. The sample included 291 males and 140 females from both the Robert J. Terry Collection and the William M. Bass Donated Skeletal Collection.
The results indicate no consistent secular change in direction or location between White males and females. Although significant secular change was present in some of the size variables, it was generally not indicative of an increase in the area of the weight-bearing surface. The findings suggest that although there is a complex relationship between joint loading and joint area, the modern secular increase in weight, coupled with a more sedentary lifestyle, has not had a sizeable effect on knee joint size.
Clinical studies have noted an increase in the presence of knee osteoarthritis over the last century. Obesity and osteoarthritis have been shown to be associated in several studies utilizing radiological data. However, often the criteria relies heavily on joint space narrowing and not the osteological/dry bone impact. The William M. Bass Donated Skeletal Collection allowed for the possible detection of a relationship between obesity and osteoarthritis of the knee because it provides a modern skeletal sample where weight is known and obese subjects are present. Including the Terry collection, housing a skeletal sample that pre-dates those found in the Bass collection, allowed for a comparison of general prevalence rates over a longer period of time.
Results are fairly consistent with clinical and radiological research, with the exception that dry bone scoring of osteoarthritis tends to produce prevalence rates much higher than possible from radiological detection. Significant associations were found between the presence of osteoarthritis and the more recent Bass collection, as expected. Age and sex also provided some significant associations with knee osteoarthritis as well.
Based on individuals with known weight, a significant association was observed between the incidence and progression of OA. Obese individuals, in particular, appear to be at a higher risk of developing knee osteoarthritis, as well as having problems with severity. There did not, however, appear to be an association between obesity and osteoarthritis of the medial tibiofemoral compartment, as some reports have posited.
Finally, the nonrandom nature of the available data allows for a comparison between randomization methods and the more traditional standard statistical algorithms that must conform to assumptions of a normal random distribution. This study found only minimal differences between the two approaches illustrating the relevance of randomization methods, while suggesting reliability in the standard tests with regard to the two skeletal samples used for this research.
Huber, Jeffrey Reed, "A Comparison of Knee Joint Size, Obesity, and Osteoarthritis Involving Two Recent Skeletal Samples. " Master's Thesis, University of Tennessee, 2004.