The underside of the patella sits in a groove within the femur called the patellofemoral groove. Within this groove, the patella moves largely lengthwise, but it has some side-to-side movement and can tilt and rotate as well.
Misalignment or repetitive contact of the joint surfaces may lead to patellofemoral pain syndrome. The result is joint irritation, inflammation, knee pain and limited range of motion in the knee.
Irritation of this joint is generally caused by the following factors:
- Acute injury to the patella
- Misalignment of the joint
- Overuse from excessive running, particularly if there is an associated weakness of knee muscles
- Chronic wear and tear of the knee joint
- Poor foot mechanics