Symptoms of patellofemoral pain syndrome include an aching or sharp pain in the knee joint, usually located at the front of the knee, or under or around the knee cap. Patients will usually complain of tenderness along the border of the kneecap and swelling will sometimes occur after running or exercise. Pain is often worse when jumping, walking or running up and down hills, climbing stairs or after sitting for prolonged periods of time. Some patients may complain of tight muscles around the knee joint and a clicking, grinding or cracking sound may occur when bending the knee(s). In more severe cases, patients may walk with a limp and will sometimes experience episodes of the knee giving way or collapsing, due to pain. In chronic cases, there may be evidence of quadriceps muscle atrophy, inflammation and softening of the underside of the knee cartilage. (chondromalacia patella) It often affects individuals who participate in vigorous exercise and adolescents during a time of increased growth and typically affects girls more than boys. In older patients, patellofemoral pain syndrome is often associated with degenerative joint changes.
Patellofemoral pain syndrome is often caused by excessively tight joints, genetic variations (knock knees and inwardly rotated thigh bones), tight muscles, a knee cap that is not properly aligned, loss of muscle strength and/or changes under the kneecap and leg injuries. In the majority of patellofemoral pain syndrome cases, there is a muscle imbalance which results in the knee cap being pulled towards the outside of the leg. This may result in abnormal movement of the knee cap when bending and straightening the knee. When the bones in the lower leg are not lined up ideally, it can cause the gliding between the knee cap and thigh bone to become abnormal. This “misalignment” can lead to overloading the movement between the knee cap and thigh bone. There are numerous factors which can cause this muscle irregularity, such as abnormal lower limb biomechanics, pain inhibition and faulty movement patterns.
Diagnosis of patellofemoral pain syndrome is determined through medical history and an examination by a medical professional. Investigation, such as an X-ray or MRI, may be used to assist with the diagnosis.
Treatment for patellofemoral pain syndrome usually involves a combination of activity modification, chiropractic adjustments, kinesiotape, weight loss and a comprehensive stretching and strengthening program. Orthotics, to correct flat feet, and soft braces, with knee cap cut-out, may be indicated. These can provide modest symptomatic relief in many cases. Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, can help reduce swelling and relieve pain, but should not be taken for an extended amount of time. Surgical intervention is rarely necessary and is generally reserved for cases of instability or severe cases that do not respond to conservative treatment.
There are additional steps that you can take to prevent recurrence of patellofemoral knee pain.
1. Wearing shoes appropriate to your activities 2. Warming up thoroughly before physical activity. 3. Incorporating stretching and flexibility exercises for the quadriceps and hamstrings into your warm-up routine, and stretching after physical activity 4. Increasing training gradually 5. Maintaining a healthy body weight to avoid overstressing your knees.
A research article in 2013 stated, “Heavy adults, with knee osteoarthritis, who lose 10% of their starting weight can significantly reduce their knee pain, walk faster and improve their mobility. Another article found a weight reduction of ~10 lbs over a 10 year period decreased risk for symptomatic osteoarthritis by 50% in women.