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Pain in the Front of the Knee

(Runner's Knee)


Paul L. Liebert

, MD, Tomah Memorial Hospital, Tomah, WI

Last full review/revision Feb 2020| Content last modified Feb 2020
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Topic Resources
  • Factors such as weak thigh muscles, excessive pronation, and tight leg muscles and tendons can cause pain in the front part of the knee.

  • People may feel pain when running downhill but eventually may have pain during walking.

  • Magnetic resonance imaging (MRI) and arthroscopy may be needed for diagnosis.

  • People should stop running until there is no pain and then use exercise to strengthen and balance muscles around the knee.

  • If excessive pronation causes pain, shoe inserts can help.

The kneecap (patella) is a circular bone that is attached to ligaments and tendons around the knee and normally moves up and down the thighbone during running.

When the Front of the Knee Hurts

Normally, the kneecap (patella) moves up and down the thigh bone during running. People may feel pain in the kneecap because thigh muscles are weak or the feet roll in too much (pronation). As a result, the kneecap rubs abnormally against the thigh bone, causing increased wear and tear.

When the Front of the Knee Hurts

Pain in the front of the knee (anterior knee pain) may be caused by

  • A kneecap located too high or too low in the front of the knee joint

  • Off-center insertion of the muscles around the knee cap

  • Tight, shortened hamstring muscles

  • Tight Achilles tendon

  • Weak thigh muscles—which normally help stabilize the knee

Runner’s knee

Weak thigh muscles are a common cause of runner’s knee, a treatable cause of anterior knee pain. Weak thigh muscles allow the kneecap to move sideways and rub abnormally against the thighbone. Runner’s knee usually starts out with knee pain when running downhill. Later, any running or walking, especially down steps, is painful.

Excessive pronation

Excessive pronation of the foot (rolling of the foot inward) when walking or running can cause knee pain. Pronation forces the thigh muscles (quadriceps) to pull the kneecap outward and rub abnormally against the end of the thighbone.

Diagnosis of Knee Pain

  • A doctor's evaluation

Doctors ask about symptoms and examine the person. Sometimes magnetic resonance imaging (MRI), arthroscopy (looking inside the joint with a flexible viewing tube), or both are needed.

Treatment of Knee Pain

  • Rest

  • Rehabilitation

Running is avoided until it can be done without pain. Ice applied to the affected area, nonsteroidal anti-inflammatory drugs (NSAIDs), and temporary use of a knee sleeve or elastic support also help. Other exercises, such as riding an exercise bike (with high seat position, low repetition, and low resistance) or swimming, can be done to protect the knee and maintain physical fitness during recovery. Exercises to strengthen and balance the muscles in the back (hamstrings) and front (quadriceps) of the thigh are helpful.

In runner’s knee, stretching before exercise can help balance the abnormal forces caused by tight muscles and reduce injury.

A shoe insert can help correct excessive pronation.

Exercises to Balance and Strengthen the Quadriceps and Hamstrings
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