Which muscle is typically weakened in patients suffering from patellofemoral pain syndrome?

Patellofemoral pain syndrome is commonly associated with a weakening of the vastus medialis obliquus muscle. This muscle is part of the quadriceps group and plays a crucial role in stabilizing the patella (kneecap) during movement, particularly when the knee is loaded in activities such as walking, running, or climbing stairs.

In patients with patellofemoral pain syndrome, the vastus medialis obliquus may not be functioning effectively, leading to maltracking of the patella. This maltracking can contribute to pain and discomfort, as the patella does not move smoothly within its groove on the femur. The weakening or delayed activation of this muscle can lead to an imbalance in the forces acting on the patella, causing excessive lateral movement, which is often associated with pain and instability.

Strengthening the vastus medialis obliquus is a common therapeutic focus in rehabilitation programs aimed at alleviating symptoms of patellofemoral pain syndrome and ensuring proper patellar tracking during knee motion.