Kinematics of Runners with and without Patellofemoral Pain during Prolonged Treadmill Running

INTRODUCTION It has been suggested that abnormal lower extremity kinematics during running are related to patellofemoral pain (PFP). Specifically, during the first half of stance when the knee is loaded, excessive internal rotation of the femur may result in lateral patellae maltracking [1,2]. Similarly, the patellofemoral joint may also be influenced by excessive knee valgus, which may be partly due to increased femoral adduction [1]. Also, it has been reported that PFP is associated with weak hip abductors and external rotators [3]. Therefore, these abnormal femoral motions may become more exaggerated in an exerted state, such as at the end of a prolonged run. Conversely, PFP has also been associated with decreased knee flexion during functional activities, which is thought to reduce the loads on the patellofemoral joint [1]. Further, the coupling that occurs between the knee and the foot may result in a decrease in rearfoot eversion as well [2].