Fat Pad Impingement
UW Health's Sports Medicine doctors treat a wide range of common athletic injuries, including fat pad impingement, which can cause knee pain.
Fat Pad Anatomy
Generalized pain in the front of the knee, also known as anterior knee pain, can have many causes. One cause is impingement of the fat pad. The fat pad is a mass of fatty tissue that lies below the kneecap (patella) and behind the patellar tendon.
Fat Pad Impingement Signs and Symptoms
Fat pad impingement can occur when the fat pad becomes swollen and inflamed due to a direct blow, hyperextension injury or chronic irritation. As a result, the bottom tip (or inferior pole) of the patella can pinch the fat pad. A person who has excessive hyperextension of the knee may also be more prone to this condition.
Fat pad impingement can be easily confused with patellar tendonitis. However, patellar tendonitis tends to cause pain only at the patellar tendon, especially at the inferior pole of the patella. Fat pad impingement will cause pain on either side of the patellar tendon, where the fatty tissue sits. The pain may be worse with jumping, prolonged standing or any other position that causes the knees to hyperextend. Also, the area around the patellar tendon may be slightly swollen. Fat pad impingement is not associated with clicking, locking or instability.
Fat Pad Impingement Treatment
Treatment of fat pad impingement is not difficult, although it can take a long time to fully recover. Applying ice before and after activities can be helpful. Use an ice bag over the affected area for 15 minutes or an ice cup for eight to 10 minutes. Modifying or limiting positions and activities that increase pain is another key to recovery. Stretching the quadriceps and hip flexor muscles may help to lessen some of the downward pressure the patella applies to the fat pad.
Anti-inflammatory medicines are also frequently used. Much less often, injections of corticosteroids to reduce inflammation or surgery to trim the fat pad are required. Rarely surgery is required to remove the inflamed portion of the fat pad.