Patellofemoral Pain Syndrome

Overview

Patellofemoral Pain Syndrome (PFPS) is a common knee problem. It involves having pain under and around the kneecap. The condition, related to issues of alignment of the knee joint, can worsen with activity or when you sit for a long time. Pain can be experienced in one or both knees.

The kneecap (patella) is connected to the thigh bone (femur) by tendons and normally moves along a groove in concert with ligaments, bone and cartilage when a person participates in sports that involve explosive leg movement or quick changes of direction. PFPS occurs when the kneecap fails to remain aligned or the muscles or cartilage become unbalanced as the patella moves on the groove of the femur.

Symptoms

Symptoms of patellofemoral pain syndrome include the following:
  • An ache in and around the kneecap, frequently experienced with walking up and down stairs and when rising from a sitting position. It is sometimes referred to as “movie-goers pain.”
  • Swelling in the knee (may not be readily visible)
  • Clicking sound with movement, but not a sense of buckling or giving way
  • Needing to walk differently or limp to diminish load on the pained leg

Causes

The exact cause of patellofemoral pain is not known, but the condition can occur with trauma or overtraining when the muscles are injured or have become weak or lack flexibility.

Risk Factors

Patellofemoral pain is more common in females in their teens who have particular knee alignment issues, such as knock-knees (“genu valgum”), in which the knees angle in and touch when the legs are straightened. A higher incidence of PFPS exists in those with increased muscle tightness due to iliotibial (IT) band syndrome or with weakness in their quadriceps muscles.

Diagnosis

Patellofemoral pain syndrome can be diagnosed with a thorough physical exam by a qualified physician. The doctor will review and test the alignment and flexibility of the leg and hip to identify deficiencies that may contribute to the condition.

Diagnostic tests may include X-rays, though they typically do not reveal abnormalities. An X-ray may show tilting of the kneecap, but this is relatively rare. An MRI can more adequately identify wear on the kneecap and help the physician to rule out other causes of pain.

Complications

If not treated, PFPS is a benign condition that can worsen, causing pain that becomes less tolerable. The condition may lead to other problems due to the resulting altered body mechanics. A person in pain may alter his gait and may grow less able to do physical activities that involve much leg movement. Walking may be become increasingly difficult, which can strongly affect a person’s lifestyle and independence.

Recovery

Reducing participation in painful activities is the most important step in addressing patellofemoral pain. These actions also can help:
  • Ice to reduce inflammation.
  • Vigilantly monitor pain levels and associated activities.
  • Replace outdated equipment, such as running shoes. Wearing shoes with thick soles helps absorb shock and load to the hip joint. Add orthotic insoles to shoes, if needed.
  • If biomechanical issues are contributing to pain, learning proper mechanics.
  • Strengthen muscles around the injured bone and adequately stretch – particularly after exercise (yoga might be beneficial).
If the patient is an athlete resuming training, the initial duration and distance of training should be reduced to half that of pre-injury levels.

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