Patellofemoral Pain (Runner's Knee)

Symptoms

• Aching around or behind the kneecap
• Pain going down stairs, squatting, kneeling, or running downhill
• Pain after sitting for a long time with the knees bent
• Occasional grinding or clicking without much swelling

Causes and who gets it

It usually comes from doing too much, too soon: increases in running mileage, hills, or jumping. Weak hip and thigh muscles and changes in training or footwear contribute.

How it is diagnosed

Diagnosis is clinical, based on the pattern of pain and an exam that rules out other problems. Imaging is usually not needed unless there was an injury, swelling, or symptoms are not improving.

Treatment

• Reduce the aggravating load for a while (mileage, hills, deep squats) rather than stopping all activity
• Exercise therapy combining hip and knee strengthening is the most effective treatment
• Patellar taping or a knee brace may help short term
• Foot orthoses may help some people in the short term
• Return to running gradually, increasing volume slowly

Recovery time

Many people improve over 6 to 12 weeks of consistent exercise, although symptoms can recur. Staying with the strengthening program helps prevent flare-ups.

When to see a doctor

• Knee swelling, locking, or giving way
• Pain after a fall or a twist
• Pain at night or at rest
• In children and teens, knee pain with a limp (hip problems can cause knee pain)

Clinical pearls

• Pain with squatting is the most consistent exam finding; patellar grind is not specific
• Combined hip and knee exercise therapy is first-line per international consensus
• Evaluate for patellar instability (apprehension, J-sign), patellar tendinopathy, and fat pad irritation
• In adolescents with knee pain and a limp, examine the hip to exclude slipped capital femoral epiphysis
• Imaging is generally unnecessary for typical presentations