Patellofemoral syndrome is the most common cause of anterior knee pain. The pain worsens with stair climbing, squatting, running or even walking and may improve with rest. Patients may complain of a “grinding or popping” sensation that may be worse upon standing up after prolonged sitting (known as the theatre sign).
The knee often may feel “full” and look somewhat swollen.
The exact cause of this syndrome is still debated on, but it is associated with poor tracking of the patella (knee cap) on the femur. Instead of gliding smoothly through the middle of the knee, the patella is positioned laterally (to the outside) during knee flexion and extension. Overuse in this misaligned position is believed to cause microscopic trauma of the patellar cartilage leading to degeneration and synovitis (internal inflammation and swelling of the knee joint).
More debate exists on the reason why the patella is misaligned laterally, but most sports physicians and physical therapists agree that weakness of the hip abductor muscles (muscles that move the leg to the side away from the other leg), weakness of the knee extensor muscles and overpronation of the foot contribute to this phenomenon. This allows the knee to “buckle” medially (inward) and the thigh muscles and tendons to pull the patella laterally (outward). Other findings associated with and contributing to patellofemoral syndrome are a tightness of the iliotibial (IT) band, hip flexors, hamstrings and calf muscles.
The common approach to treating patellofemoral syndrome includes relative rest, taping or bracing and physical therapy exercises. Avoiding activities that cause pain will allow the patellar cartilage to heal without further injury. Taping or bracing may be used to prevent the patella from being pulled laterally during activities. Physical therapy exercises are the most important part of treatment. Strengthening exercises are focused on the hip abductors (mainly the gluetus medius muscles), the hip external rotators (mainly the piriformis muscle) and the knee extensors (all quadriceps muscles). Closed chain exercises are often used early on as they are thought to produce less stress on the joint and provide a more functional recovery. Flexibility exercises focus on stretching of the tensor fascia lata muscle, IT band, hamstrings, hip flexors and the calf muscles.
Other physical therapy exercises that should be included in the regimen are core strengthening and balance training. A strong core provides a foundation for all other muscles to function properly. Doing one leg balance exercises is a great way to functionally incorporate all the muscles involved (including the core) and sharpen up your nervous system’s awareness of your body. Such a comprehensive therapy approach usually yields the best recovery.