Comparison of foot pronation and lower extremity rotation in persons with and without patellofemoral pain.

Abnormal foot pronation and subsequent rotation of the lower extremity has been hypothesized as being contributory to patellofemoral pain (PFP). The purpose of this study was to test the hypothesis that subjects with PFP would exhibit larger degrees of foot pronation, tibia internal rotation, and femoral internal rotation compared to individuals without PFP. Twenty-four female subjects with a diagnosis of PFP and 17 female subjects without PFP participated. Three-dimensional kinematics of the foot, tibia, and femur segments were recorded during self-selected free-walking trials using a six-camera motion analysis system (VICON). No group differences were found with respect to the magnitude and timing of peak foot pronation and tibia rotation. However, the PFP group demonstrated significantly less femur internal rotation compared the comparison group. These results do not support the hypothesis that individuals with PFP demonstrate excessive foot pronation or tibial internal rotation compared to nonpainful individuals. The finding of decreased internal rotation in the PFP group suggests that this motion may be a compensatory strategy to reduce the quadriceps angle.