Discriminating sex in South African blacks using patella dimensions

Abstract

The patella is the largest sesamoid bone that develops within the quadriceps femoris muscle tendon. Since the shape and size of the patella relies on the strength of the muscle mass, it is likely that stronger muscle masses could alter the shape and size of this bone. Given that females have a smaller build than males, it can be hypothesized that some measurements of the patella will display sexual dimorphism. A total of 120 (60 males and 60 females) patellae of South African Blacks were measured. The age range was between 18 and 70 years. Since it has been previously shown that there are no statistically significant intertribal differences in osteometric dimensions of the South African Black population group, data were collected from two large groups, the Zulu and Xhosa tribes. Only the left patellae were measured, and patellae that had any signs of pathology or abnormality were excluded from the study. Six features were measured for each patella. The Statistical Product and Service Solutions (SPSS) program was used to derive the equations. Stepwise and direct analyses were performed. The highest rate of classification was 85 percent, thereby making the patella useful for sex determination; however, the equations developed from this study should be used with caution in forensic cases and only when the patella is the only bone available with sexual dimorphic features. Also, the equations should only be applied to the South African Black population.