Patellofemoral Joint

The stability of the patellofemoral joint is influenced by interaction of the bony anatomy, alignment, and soft tissue stabilizers. The patella and the trochlea have morphologic variations that can increase the risk of patellar instability. The bony alignment of the knee, measured clinically or radiographically, is a major factor that determines the lateralizing vector on the patella. The main soft tissue stabilizers are the medial and lateral patellofemoral complexes, which are parts of the medial and lateral retinacula. We discuss the interaction of these factors on contact areas of the patella throughout range of motion, as well as on the stability of the patella in relation to the femoral trochlea.