PATELLAR PAIN SYNDROME

Patellofemoral pain syndrome is an overuse (not traumatic) condition that produces pain under the kneecap (patella).  Patellofemoral pain syndrome is often termed chondromalacia patella, runner’s knee or moviegoer’s knee.

On examination, the kneecap is often tender at the lower and outer margins— underneath the patella and at the outside of the knee. In more severe cases, patients may also experience pain around the entire joint and even in the back of the knee.

Patients who suffer from patellofemoral pain syndrome have an uneven distribution of load across their kneecap that produces the pain/discomfort.  Occasionally, this is due to tilting of the kneecap as it sits in the groove, but more often it occurs in patients with completely normal x-rays.  It is often the result of an imbalance in strength and or flexibility.

The main muscle groups that ‘unload’ or protect the patella are the abductors (gluteal muscles) and quadriceps (thigh muscles) and when patients experience pain, the pain itself inhibits these muscles from firing and from getting stronger.

Patellofemoral pain syndrome is more common in women than in men. Women ’s normal standing alignment produces more of a pull outward on the kneecap and this places increased pressure on this part of the knee and increases the risk of this ‘uneven’ loading of the joint.

Patellofemoral pain is evaluated with a thorough history, physical exam,  including assessment of any imbalances in strength and flexibility that may be present from the core (abdominal muscles) to the floor (the position of the feet).   Patellar pain can be exacerbated by other factors that place uneven stress across the joint, including flat feet, abnormal rotation of the hips and tightness of the IT band and hip flexors. Plain x-rays and MRI are often used to assess the bones, alignment, and cartilage surfaces of the kneecap and trochlea.

Often the pain begins with sports or running but may become present during everyday activities. Patients often notice pain with:

• Ascending or descending stairs
• Prolonged sitting or going from a sit to a standing position
• squatting, kneeling and lunging
• Wearing high heels

Patients with patellofemoral pain syndrome often find walking on the flat/level ground to be an easier activity for their knees to tolerate.

Non-Surgical Treatment

The first step in the treatment of patellofemoral pain syndrome is to quiet the knee with a combination of anti-inflammatory medications, frequent application of ice, and resting the knee from aggravating activities. Temporary activity modification is critical to allow the knee to begin strengthening in a pain-free state.  This most often means stopping participation in high impact sports and high-intensity workouts, squats, and lunges. If the patient has flat feet, orthotics might be needed. In some cases, a cortisone injection is given to decrease inflammation in the knee so that the patient can tolerate a stretching and strengthening program. Other injections such as lubricating injections (called viscosupplementation or hyaluronic acid) can be useful to decrease pain.

Physical therapy is critical to loosen any tight tissues and to improve functional strength throughout the leg and hip. Taping may also be useful during physical therapy to minimize discomfort and allow patients to participate in more advanced strengthening exercises without pain.  In some cases, if physical therapy doesn’t produce the expected improvement, an MRI may be performed to detect early cartilage changes.

Often we see patients experiencing continued pain after having undergone lateral release surgery, with other providers.  A lateral release opens the retinaculum, a tissue that acts as an envelope around the knee and runs around the joint, Continued pain after this procedure often indicates that other contributing factors to patellofemoral pain have not been addressed.

A lateral release can be helpful when performed with a larger surgery, as part of the soft tissue balancing, to address a dislocating or arthritic patella (combined with a tibial tubercle transfer or MPFL reconstruction). As a sole or isolated procedure, however, it is rarely an appropriate treatment and then only for those who have not responded to extensive physical therapy.

Surgical Treatment