Patellofemoral Pain Syndrome – Runner’s Knee

What is patellofemoral pain syndrome or runner’s knee?

The knee joint is one of the more complex joints in the human body and is involved in several major motions such as running, jumping, and squatting. The patella (kneecap) is a small triangular bone cushioned by soft articular cartilage that provides an attachment point for both the quadriceps tendon, which connects to the femur (thigh bone), and the patellar tendon, which connects to the tibia (shin bone). When the knee is in a bent position, the patella should lie comfortably in the trochlear groove at the distal end of the femur. However, most commonly in athletes but also occurring in patients at any activity level, the articular cartilage that cushions the patella can become frayed, causing anterior knee pain in a condition called patellofemoral pain syndrome or runner’s knee. Doctor Benedict Nwachukwu, orthopedic knee specialist, can successfully treat patients in Manhattan, New York City and the surrounding New York boroughs who are experiencing symptoms of runner’s knee or patellofemoral pain syndrome.

What causes runner’s knee or patellofemoral pain syndrome?

Repetitive motions, overuse, and muscular imbalances are the most common causes for the development of patellofemoral pain syndrome. Normally, the vastus medialis oblique (VMO) pulls the tendons inward while the vastus lateralis and iliotibial band (IT band) pull the tendons outward, keeping the patella within the trochlear groove. With patellofemoral pain syndrome, the VMO, or the quadriceps muscle that sits on the medial side of the femur (inside of the thigh), tends to be weaker than the vastus lateralis and the IT band, or the quadriceps muscles that sit on the lateral side of the femur (outside of the thigh). The tighter vastus lateralis and IT band pull the tendons outward while the weakened VMO does not provide the resistance necessary to prevent the patella from tracking laterally outside of the trochlear groove, which then causes friction and pain due to the breakdown of the patella’s protective articular cartilage.

What are the symptoms of patellofemoral pain syndrome?

Most commonly with patellofemoral pain syndrome, patients will experience pain after resting periods, especially while the knee is bent. For example, a patient may experience patellofemoral pain after watching a long movie. Patients may also experience pain accompanied by swelling and/or pain accompanied by a “clicking” or “grinding” sensation due to extreme wear in the cartilage. This sensation may also indicate a more serious tear in the cartilage.

How is patellofemoral pain syndrome diagnosed?

After obtaining a comprehensive medical history and summary of regular physical activities, Dr. Nwachukwu will perform an extensive examination of the knee joint and its range of motion. Usually, patellofemoral pain syndrome is diagnosed via physical examination, but further diagnostic imaging may be deemed necessary in some cases to rule out other conditions that may be causing pain in the knee joint.

How is patellofemoral pain syndrome treated?

Non-Surgical Treatment:

Most often, patients with patellofemoral pain syndrome will recover with non-surgical therapies such as RICE (rest, ice, compression, elevation), NSAIDs (non-steroidal anti-inflammatory drugs) for pain relief, and taping the knee to help correct the patella from tracking outside of the trochlear groove. After the pain and inflammation are managed, Dr. Nwachukwu will recommend a physical therapy regimen to strengthen the VMO while stretching the tight vastus lateralis and IT band.

Surgical Treatment:

In the rare cases where patellofemoral pain syndrome is resistant to non-surgical treatment and pain or inflammation persists, arthroscopic surgery may be performed to alleviate the condition. Dr. Nwachukwu will insert a small surgical camera (arthroscope) into the knee joint to visualize the articular cartilage underneath the patella, and assess one or more of several courses of action to relieve the pain:

• Debridement: An arthroscopic shaver is used to remove (debride) fibrillation (eroded areas of cartilage).
• Lateral Retinaculum Release: If the lateral retinaculum (a fibrous tissue that supports the outer side of the patella) is found to be tight enough to pull the patella laterally outside of the trochlear groove, a lateral release procedure can loosen the tissue and allow the patella to settle inside the groove once again.
• Tibial Tubercle Transfer: This procedure is most commonly used to treat patellofemoral instability, where the patella persistently tracks out of the trochlear groove. This is done through a midline incision over the knee, through which Dr. Nwachukwu will reposition the tibial tubercle (bony attachment at the top of the shin) and attached patellar tendon to a new insertion point on the tibia.

For more information on patellofemoral pain syndrome or runner’s knee, and the excellent treatment options available for your knee pain, please contact the office of Benedict Nwachukwu, MD, orthopedic shoulder specialist serving Manhattan, New York City, and surrounding New York boroughs.