Anterior knee pain is a characterized by a chronic pain over the front and centre of the knee joint. It is common in athletes, active adolescents (especially girls) and overweight individuals. Anterior knee pain refers to a variety of conditions which include runner’s knee or patellar tendinitis and chondromalacia of the patella. There is an inter-individual variation in the duration and presentation of pain.
The knee joint is a large, complex joint in the body comprising of three bones, i.e. the lower end of the thigh bone or femur, upper end of the shinbone or tibia, and the kneecap or patella. The patella moves over the joint and allows bending of the knee and straightening of the leg. There are a few major ligaments situated around the knee joint which hold the joint firmly in position and contribute to the stability of the knee.
Anterior knee pain usually develops due to improper movement of the knee cap causing it to rub against the lower end of the femur bone. This may occur secondary to an imbalance or poor flexibility of the thigh muscles that stabilize the knee joint, problems with alignment of the knee joint, flat foot, tightness or weakness of the front and back muscles of the thigh, excessive sports activities, improper sports training techniques or improper use of equipment. Other possible causes for anterior knee pain include arthritis, cartilage injury and dislocation or fracture of the patella or knee cap.
Pain is the predominant symptom and is usually gradual in onset. Patients may experience a dull aching pain around the sides, below or behind the knee cap. Sometimes, climbing stairs and standing up or walking after prolonged sitting may produce a popping or cracking sound in the knee. The pain may also be present at night and be exaggerated by any repetitive knee bending activity such as jumping, squatting, running or weight lifting. Any changes in the activity level, playing surface or equipment may also result in pain.
Diagnosis of anterior knee pain includes a medical history and physical examination along with imaging tests such as X-ray and MRI scan. Physical examination determines the cause of pain and other related problems while X-rays and MRI scan aid in confirming the condition by providing visualization of the internal structures.
A majority of patients respond to conservative treatment which includes application of ice, rest and well programmed rehabilitation exercises. Ice helps to relieve the swelling and inflammation, rest protects the joint from repetitive injury while stretching and mobilization exercises improve muscle strength, flexibility and range of motion. Sometimes, if needed, pain relieving medication and anti-inflammatory drugs may also be used. Surgical treatment is rarely indicated.
Chronic persistent pain needs to be reported to the doctor immediately. Once the pain has been treated, a recurrence can be prevented by following a few simple measures which include: