Patellofemoral Pain (Runner’s Knee)

Diffuse aching around or behind the kneecap rather than a sharp point of pain. Worse going down stairs, squatting, kneeling, and after prolonged sitting. Pain after sitting supports the diagnosis but does not make it: the defining feature is pain around or behind the kneecap brought on by loading the bent knee, and pain on squatting is the most useful single test 6.

It is one of the most common knee problems in active people, accounting for 25–40% of knee problems seen in sports injury clinics 3, and it frequently has no structural finding on a scan. That is not a failure of diagnosis; it reflects that the problem is load distribution rather than damage.

Weakness of the hip abductors and external rotators allows the thigh to rotate inwards under load, which changes how the kneecap tracks. Exercise reduces pain whether it targets the hip or the knee, and head-to-head trials have not settled which of the two is better 3.

Programmes that combine hip and knee exercises reduce pain and improve function more than knee exercises alone 3 4, which is why an assessment looks above the knee before prescribing.

Progressive hip and quadriceps strengthening, movement retraining for the tasks that hurt — stairs, squats, landing — and load management to reduce the volume that provoked it without stopping activity.

Taping and orthoses can reduce symptoms enough to allow the exercise in the short term. They do not substitute for it, and the evidence for them alone is weak.

Recovery is often slower than hoped: in two trials with 310 participants, 55% still reported an unfavourable recovery at three months and 40% at twelve months, whatever treatment they received 5. Symptoms can recur and persist for years 1, which is why the strengthening should not stop the moment the pain settles.

Imaging is not routinely needed. It is indicated where there was a specific injury, where the knee locks or gives way, or where symptoms do not fit the pattern.

Scans in this condition are usually normal or show findings unrelated to the pain, including cartilage changes present in people without symptoms. It is a diagnosis made from the history and the examination.

That matters because a normal scan is frequently taken as meaning nothing is wrong, when the problem is a load and control issue that imaging was never going to show.

Usually, if the running is adjusted rather than stopped. In a randomised trial of 69 runners, an 8-week programme of education on managing symptoms and training load improved pain and function as much as the same education combined with exercises or with gait retraining 7. Technique still changes the load on the joint: in a laboratory study of 30 healthy adults, raising step rate by 10% lowered peak patellofemoral force by 14% 8. The trial was small and exercise remains the treatment with the strongest support overall 3, but it puts training-load management at the centre of care for runners 7.