Running Injury Series: Runner’s Knee (Patellofemoral Pain Syndrome)

Patellofemoral pain syndrome is a common condition in the running population. Patellofemoral pain syndrome (PFPS) is also commonly called runner’s knee or a patella tracking dysfunction. 

Symptoms 

Patellofemoral pain syndrome symptoms include pain, which is usually vague, that is located around the patella (knee cap). The most common activities that cause pain are running, squatting, or stair climbing and may also be felt with prolonged sitting. 

Cause

Although it has been difficult to determine the exact cause of PFPS, there have been several theories on the mechanism. A previous theory was an imbalance between the inside quadricep muscle (vastus medialis) and the outside quadricep muscle (vastus laterialis). This would cause the patella to shift to the outside because of a weak inside quad (the VMO muscle was at fault). 

More recent research into PFPS suggests that it is actually internal rotation of the femur that causes irritation and pain. The patella normally sits in a V-like groove in the femur. If the location of the patella in the groove is altered, it can cause irritation and pain. When the femur is internally rotated, it causes the patella to shift to the outside resulting in patellofemoral pain. 

Patellofemoral pain syndrome is sometimes confused with chondromalacia patella. Chondromalacia patella is actually degeneration of the cartilage in the groove that the patella sits in. This is typically the result of repetitive dysfunction in the patellofemoral joint. 

Prevention 

Foam rolling the quads is a good place to start. Lying prone with the foam roller placed just above the knee cap, roll the foam roller up your leg. If you need to add more pressure, stack one leg on top of the other. If you don’t have a foam roller (which you should), the couch stretch made famous by Kelly Starrett is another great exercise (stretch starts at about 1:30. Just a warning, this video is pretty intense). 

Strengthening the external rotators of the hip can also help prevent patellofemoral pain syndrome. If the stabilizers of the hip fatigue during your run, you will use the passive structures to support you (ligaments and bone). A beginner’s exercise for the external rotators of the hip is the clam shell exercise. Lying on your side with your knees bent. Place a band around your knees. Slowly rotate your top leg, keeping your pelvis stationary. You may need to use a wall to make sure your pelvis doesn’t move. 

Treatment

Conservative treatment options, such as chiropractic care, manual therapy, and kinesiology tape, are usually successful in the treatment of patellofemoral pain syndrome. 

Chiropractic care can aid in correcting joint dysfunctions effecting the knee. Altered movements in the hip and sacro-iliac joint are common culprits in patellofemoral dysfunction. 

Manual therapy can be used to decrease tension in the quadriceps and other muscles that are contributing to the pain syndrome. 

Kinesiology tape is beneficial in helping the patella move properly. The tape can be used to help the patella track in the groove, relieving the pain.