Pain in the front of the knee, often termed patellofemoral pain, is one of the most common causes of knee pain in patients, especially younger athletic patients that participate in activities such as running and biking. There are several areas in the front of the knee that can be the cause of pain:
The patella, or kneecap, has a thick cartilage surface that allows it to glide smoothly in the knee. The cartilage can become injured, either by altered alignment or increased pressure, resulting in pain.
The patellar tendon connects the patella to the tibia in the front of the knee. The patellar tendon can become inflamed with activities such as running and jumping. This is commonly termed ‘Jumpers’ knee’.
the retinaculum is a thin band of tissue that runs on either side of the patella and connects it to the femur (thighbone). Patients with pain from the retinaculum often have pain on both sides of the patella that increases with activities.
Symptoms and Diagnosis
In patients who have persistent pain in the front of their knee, an evaluation by an orthopaedic surgeon is warranted. The diagnosis of patellofemoral pain can be made with a combination of history, physical exam, and imaging studies.
Patients often complain of pain in the front of the knee, especially with running or sporting activities. The pain can feel deep, under the kneecap, and sometimes is associated with mild swelling.
On physical exam, the surgeon evaluates the knee for swelling, any instability, and tenderness around the patella. Radiographs help determine if the patella is normally aligned within its groove (trochlea) in the knee. If cartilage injury is suspected, an MRI is usually obtained.
The treatment of patellofemoral pain depends on the specific problems that is causing the pain. In most cases, the soft tissue (retinaculum and patellar tendon) are the source of the pain and can be treated with a program of rest, ice, activity modification, stretching, and strengthening of the knee. Stretching of the hamstring can be particularly helpful in alleviating patellofemoral pain.
An evaluation of patellofemoral pain by a physical therapist can be particularly valuable. Physical therapists can help evaluate the tracking of the patella and do treatments such as patella taping, massage, and ultrasound to improve symptoms. A brace can be worn as well to help the patella track correctly during athletic activities.
In some cases, surgery is necessary to correct malalignment or damage to the cartilage under the kneecap. In cases where the cartilage if frayed under the patella, an arthroscopic procedure can be performed to clean up the frayed cartilage. If the patella is badly aligned a surgical procedure may be needed in order to realign the patella.