Patellofemoral Biomechanics Considerations: Analysis of Factors Contributing to Patellofemoral Pain.

Patellofemoral pain syndrome is a common cause of anterior knee pain. It has a prevalence of 22.7% in the general population and tends to affect females more than males. Understanding the anatomy of the hip, knee, ankle, and foot helps to assess biomechanical risk factors that contribute to the development of patellofemoral pain syndrome. At the knee, decreased knee flexion angle, knee flexion and extension strength, and increased frontal plane projection angle have been shown to increase the risk of developing patellofemoral pain syndrome. Increased femoral internal rotation, weak hip external rotators, and an increased dynamic Q angle have been identified as hip biomechanical risk factors. Foot and ankle risk factors include excessive foot pronation, pes planus, pes cavus, and limited ankle dorsiflexion. Biopsychosocial factors, like kinesiophobia, also may contribute to patellofemoral pain syndrome. It is important to consider all these factors together when assessing and treating patients with anterior knee pain.