Patellofemoral pain: Where does it originate and how to get rid of it
Pain in the front of the knee is usually called patellofemoral pain, but may originate in any of innervated structure around this part of the knee, or be referred from the hip or back. Anterior knee pain walking down stairs or running is a fairly common cause of time lost from sports and vigorous activity. Irritation of structures around the patella – retinaculum and synovium – from overuse or imbalances also can cause pain.
Such anterior knee pain will usually get better with rest and other nonoperative treatment, which may include ice, weight loss, bracing, taping, anti-inflammatory medicine, stretching and strengthening. A good physical therapist can be extremely helpful when home exercises, weight loss and rest fail to restore normal function. In patients who have lower extremity imbalances, strengthening of “core stabilizers” with the help of a therapist will help reduce abnormal pressures on and around the patella. Some patients also benefit from management of depression and anxiety.
Surgery is rarely needed for patellofemoral pain. One reason for surgical intervention is intractable pain in the peripatellar retinaculum from chronic imbalance, particularly lateral tilting of the patella, or injury. Releasing the painful retinaculum in a limited way may relieve this type of pain when injection or therapy directed to it fails. Other patients may require removal of a chronically tender synovial band of tissue or plica.
John P. Fulkerson
In some people, the distal or lateral patella cartilage may soften and become chronically painful such that descending stairs is difficult. This is typically a result of abnormal patella entry into the femoral groove recurrently. With vigorous activity, cartilage may break down yielding a deficient weight bearing surface that then transmits excessive stress to the underlying, innervated bone. This underlying bone then becomes irritated and causes pain.
We can see and probe such areas with an arthroscope, but treatment is difficult. Drilling such areas to create a healing response followed by prolonged rest, and even unloading of the damaged area by anteriorization or anteromedial tibial tubercle transfer may be necessary in resistant cases with a chronically painful articular defect and subchondral pain. After severe articular cartilage impact (dashboard knee) causing chronic pain, cartilage transplantation or resurfacing may be appropriate in rare cases. However, many patients can be managed with rest and modification of activity, as well as bracing and weight loss.
In summary, the person with persistent anterior knee pain should seek the advice of a skilled health care professional and exhaust nonsurgical methods of treatment. Surgery should be considered only for resistant, well-documented, painful lesions amenable to a specific targeted intervention when all nonoperative alternatives have failed. Determining appropriate treatment is based on correct identification of the source of pain.