Written and reviewed by the BPR clinical team. Last reviewed: 30 July 2026. This article is for education and is not a substitute for individual assessment, diagnosis or treatment by a qualified healthcare professional.
It's a dull ache right at the front of the knee, around or behind the kneecap. It grumbles going down stairs, flares when you squat, and nags after a long car journey or a film — the so-called “theatre sign.” This is patellofemoral pain, one of the most common knee complaints in active people and runners. It has a reputation for being frustratingly persistent, but the reassuring truth is that it's usually not a sign of damage, and it responds well to the right exercise.
What is patellofemoral pain?
Patellofemoral pain is pain arising from the joint between your kneecap (patella) and the thigh bone behind it. Rather than any single structure being injured, it's best understood as the kneecap area being loaded more than it can currently tolerate. That distinction matters: the problem is usually about load and capacity, not lasting harm to the joint (Willy et al., 2019).
Why does it happen?
The most common trigger is a change in load — a spike in running, a new training programme, more hills or stairs than usual. Underlying that, the strength and control of your hip and thigh muscles often play a big role: when the hip doesn't control the leg well, the kneecap is loaded less evenly. Foot mechanics can contribute too. As with most overuse problems, it's rarely one thing — more often a busy few weeks landing on a knee that wasn't quite prepared for it.
What does it feel like?
The pain is usually a diffuse ache around the front of the knee — harder to pinpoint with one finger than, say, patellar tendon pain. It's typically worse going downstairs, squatting, kneeling and after prolonged sitting with the knee bent. Some people notice a grinding or clicking, which on its own isn't a cause for concern.
How it's assessed
We'll take your history, then reproduce your pain with movements like squatting or step-downs, and assess the strength and control of your hip and thigh. We'll also check how you move on a single leg. Part of the job is telling it apart from other front-of-knee problems — patellar tendinopathy (pain at the tendon just below the kneecap) or early osteoarthritis — because the plans differ.
What the evidence says
- Exercise is the most effective treatment. A Cochrane systematic review found that exercise therapy reduces pain and improves function in patellofemoral pain (van der Heijden et al., 2015).
- It's not just about the knee. The same review found that combining hip and knee exercises gives greater pain relief than knee exercises alone — which is why we target the hip and pelvis, not only the thigh (van der Heijden et al., 2015; Collins et al., 2018).
- Guidelines back exercise first. The clinical practice guideline recommends exercise therapy, particularly combined hip- and knee-targeted exercise, as the core treatment, with taping or foot orthoses as short-term adjuncts (Willy et al., 2019).
How it's treated
The cornerstone is exercise therapy, and the evidence is strong and consistent. Strengthening the hip and knee muscles — particularly those that control the thigh and pelvis — reduces pain and improves function, usually over a matter of weeks to a few months. Alongside that, managing your training load stops you feeding the problem while you build capacity.
Short-term add-ons such as taping or foot orthoses can settle symptoms enough to let you exercise and stay active, but they work best as supports rather than stand-alone fixes. Just as important is the message that this pain isn't damaging your knee — understanding that makes it far easier to keep moving and loading sensibly, which is exactly what recovery requires.
What you can do yourself
Focus on hip and thigh strengthening, and temporarily pull back the activities that spike your pain — particularly downhill running, deep squats and lots of stairs — while you build up. Use the 24-hour rule: some discomfort with exercise is fine as long as it settles by the next day. Reintroduce your sport gradually.
When to seek help
When to seek help. Seek prompt review if your knee swells significantly, locks, gives way, or the pain followed a specific injury — these suggest something other than simple patellofemoral pain. Otherwise, see a clinician if the pain keeps returning, limits your activity, or isn't improving with your own efforts.
Frequently asked questions
Is it safe to keep exercising with kneecap pain?
Usually yes. Complete rest tends to make it worse. The aim is to modify load — easing the activities that spike pain while you strengthen — rather than stopping altogether.
Will patellofemoral pain lead to arthritis?
There's no good evidence that it directly causes arthritis. It's a load-related pain, not a sign of a joint wearing out.
How long does it take to get better?
Many people improve within 6–12 weeks of consistent strengthening, though more stubborn cases take longer. Consistency matters more than intensity.
Do I need a scan?
Usually not. The diagnosis is made from your history and examination; scans rarely change the plan.
Should I stretch or strengthen?
Strengthening — especially of the hip and thigh — is the priority and has the strongest evidence. Some stretching can help alongside it.
How BPR can help
At BPR we'll confirm what's driving your knee pain, test the hip and thigh strength that usually sits behind it, and build a strengthening plan that gets you back to stairs, squats and running comfortably. You can book an assessment at bpr.rehab.
References
- van der Heijden, R.A., Lankhorst, N.E., van Linschoten, R., Bierma-Zeinstra, S.M.A. and van Middelkoop, M. (2015) 'Exercise for treating patellofemoral pain syndrome', Cochrane Database of Systematic Reviews, 1, CD010387. doi:10.1002/14651858.CD010387.pub2.
- Collins, N.J., Barton, C.J., van Middelkoop, M. et al. (2018) '2018 Consensus statement on exercise therapy and physical interventions for patellofemoral pain', British Journal of Sports Medicine, 52(18), pp. 1170–1178. doi:10.1136/bjsports-2018-099397.
- Willy, R.W., Hoglund, L.T., Barton, C.J. et al. (2019) 'Patellofemoral pain: clinical practice guidelines', Journal of Orthopaedic & Sports Physical Therapy, 49(9), pp. CPG1–CPG95. doi:10.2519/jospt.2019.0302.