The main compartments of the knee are where many of the serious knee injuries occur such as meniscus (cartilage) tear, ligament damage etc. However a high percentage of knee pain comes from the anterior structures of the knee including the patella (kneecap), the patella tendon and various other structures. Anterior knee pain is usually worse on stairs (especially descending) and bad for squatting or kneeling.
Adolescent knee pain
In children and teenagers, especially sporty ones, there are some common problems of the anterior knee. So called patellofemoral pain syndrome is pain associated with abnormal stresses on the knee. Often there is no obvious structural damage seen on MRI. Causes may include misalignment of the patella, flat feet, hypermobility and lack of muscle strength. In cases where there is softening of the cartilage at the back of the patella this is known as chondromalacia patellae. Another common problem in the young is Osgood-Schlatter disease in which the pull of the quadriceps muscle causes multiple small fractures where the tendon attaches to the bone. It is self-limiting but often leaves the patient with life long bony lumps just below the knee caps.
Adult anterior knee pain
A common problem in middle and older age is osteoarthritis at the back of the kneecap. The pain is often hard to localise and may be accompanied by crepitus, clicking and swelling. Bursitis is also common. A bursa is a fluid filled sac which can become inflamed in conditions with antiquated names such as house maid’s knee and parson’s knee. Tendinopathy of the patella tendon is another overuse syndrome which is also known as jumper’s knee. More recently, new pain syndromes have been identified. Fat pad impingement occurs when this highly pain sensitive structure gets pinched between kneecap and thigh bone. Plica syndrome is when an extension of the synovial membrane of the knee becomes pinched in a similar way.
Diagnosis and Treatment
Anterior knee pain is a complex subject and the experienced practitioner will still often require the back up of MRI scanning to support a clinical examination. The majority of the problems described will respond to careful management, hands-on treatment, exercises and correction of misalignment. More severe cases may involve referral to podiatrists, surgeons etc.