Anterior Knee Pain-Patella Femoral Syndrome

Anterior knee pain (patella femoral syndrome) is very common in athletes. Typically, pain is increased during activities involving stair climbing, squatting or kneeling. Patella femoral syndrome is caused by an irritation on the undersurface of the patella or knee cap, which can lead to softening and eventual loss of the cartilage lining the bone of the joint. There are many causes for patella femoral syndrome including malalignment of the lower extremity expressed as flat feet, knock knees, or internally rotated hips. The patella glides up and down in a shallow groove at the front of the femur or thigh bone. Patella femoral syndrome is generally caused by an imbalance of the muscle forces around the knee cap causing it to pull laterally and produce abnormal stresses on the undersurface of the knee cap. This is similar to having the front tire of your car slightly out of alignment leading to abnormal wear on the tire. 

Other causes for patella femoral syndrome include weak quadriceps muscles, injury to the knee, obesity and overuse. Initial treatment involves reducing inflammation and re-establishing the proper alignment between the knee cap and its groove. Rest is used for the painful swollen knee until symptoms improve. Stair climbing and squatting are avoided. Ice and anti-inflammatory medications are also used to decrease inflammation. Treatment is directed at strengthening the thigh muscles of the inside of the knee and stretching of the tight muscles and connective tissues of the outside of the knee. Malalignments of the flat feet are corrected with shoes with good medial arch support or through the use of orthotics. Hip rotation is improved through stretching exercises.

Most athletes will respond to this regimen return to sports. Rarely surgery may be indicated in cases of gross malalignment or unresponsiveness to appropriate activity modification, stretching, icing, and strengthening.