Understanding your knee cap pain

In this section, you can learn more about knee cap pain by scrolling down the page.

You can also click on the links to the left to quickly access answers to common questions about your knee cap pain.

If you are a runner, we have a specific section for you here.

Diagnosis of your knee cap pain will most likely be termed patellofemoral pain, and should be provided by a suitably qualified health professional. Other common terms include chondromalacia patellae and runners knee.

This infographic does not replace consultation with a physiotherapist or doctor, but it might help you to understand if you have knee cap pain (patellofemoral pain).



Imaging (Scans)

Some people believe that changes in structure (e.g. cartilage) of the knee joint is the cause of knee cap pain. However, research suggests no difference between people with knee cap pain and people without pain on MRI and X-ray. Therefore, imaging is not likely to help with knee cap pain diagnosis, or in determining appropriate treatments.

Supporting articles

Crossley 2016. Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 1: Terminology, definitions, clinical examination, natural history, patellofemoral osteoarthritis and patient-reported outcome measures.

Drew 2016. Which patellofemoral joint imaging features are associated with patellofemoral pain? Systematic review and meta-analysis.

van der Heijden 2017. Structural Abnormalities on Magnetic Resonance Imaging in Patients With Patellofemoral Pain: A Cross-sectional Case-Control Study.

It is common for you to have knee cap pain at the beginning of your treatment. However, your pain should not achieve high levels in any physical activity you perform. That’s why we are providing 5 tips for you manage your knee cap pain during physical activities.

Use this infographic to guide acceptable pain levels:


Fear of movement may exist in patients with knee cap pain. However, the most recommended intervention for knee cap pain is exercise, passive treatments are not likely to help.

Despite being quite common for patients with knee cap pain to be fearful of some movements (e.g. running, jumping and walking on stairs). Some studies report that reductions in fear of movement are related with reductions in the level of knee pain. Therefore, it is highly recommended for patients to keep doing all daily activities alongside the exercise program.

If you are not so confident to walking on stairs at the moment, you may find the following infographic helpful.


Supporting articles

Domenech 2014. Changes in catastrophizing and kinesiophobia are predictive of changes in disability and painafter treatment in patients with anterior knee pain.

Priore 2019. Influence of kinesiophobia and pain catastrophism on objective function in women with patellofemoral pain.


Knee crepitus or noisy knee is a common complain/concern of people with knee cap pain. We don’t know what causes the noise on the knees. But, recent data show that people with knee cap pain who have noisy knees have similar levels of pain, function, fear of movement and knee strength compared to those who don’t have noisy knees. In other words, if you have knee cap pain and a noisy knee, it doesn’t mean your condition is worse than those who have knee cap pain and no noisy knee.

Additionally, a previous study investigated 250 asymptomatic knees (knees with no pain) and found that 99% of people had knee crepitus.

Supporting articles

De Oliveira Silva 2018A. Implications of knee crepitus to the overall clinical presentation of women with and without patellofemoral pain.

De Oliveira Silva 2018B. Knee crepitus is prevalent in women with patellofemoral pain, but is not related with function, physical activity and pain.

Pazzinatto 2019A. What are the clinical implications of knee crepitus to individuals with knee osteoarthritis? An observational study with data from the Osteoarthritis Initiative.

Pazzinatto 2019B. Knee crepitus is not associated with the occurrence of total knee replacement in knee osteoarthritis – A longitudinal study with data from the Osteoarthritis Initiative.

McCoy et al. (1987) Vibration arthrography as a diagnostic aid in diseases of the knee. Journal of Bone Joint Surgery (69), 288-293.

Robertson et al. (2017) People’s beliefs about the meaning of crepitus in patellofemoral pain and the impact of these beliefs on their behaviour: A qualitative study. Musculoskeletal Science & Practice. (28), 59-64. doi: 10.1016/j.msksp.2017.01.012

Physical activity is excellent, but, do you know that doing ‘too much, too soon’ may be a key reason you develop or continue to have knee cap pain?

If you are not sensible, other things may not help to manage your pain. That’s why managing load is very important.

Take a look at the short video below to get some tips on how you can manage your physical activity load (it’s less than two mins)!


Why do I need to be sensible with how much exercise I do?

The exact reason why people develop knee cap pain is unclear. However, experts around the world tend agree that doing ‘too much, too soon’ in relation to exercise may be a key reason.

There seems to be a spike in the number of people with knee cap pain following rapid increases to how much exercise you do – e.g. basic military training or ‘start to run’ programs (e.g. couch to 5KTM).

The number of people developing knee cap pain when completing basic military training has been reported to be as high as 32%.

In ‘start to run’ programs it can be as high as 17%.

There are no specific rules on how much exercise you should complete in order to avoid developing knee cap pain. It is also not clear exactly how quickly to increase exercise when returning to sports and other activities if you are recovering from knee cap pain.

The most sensible option is to monitor your pain levels during and after exercise. Experts frequently recommend that if you have a large increase in pain, or pain stays increased for more than 24 hours after exercise, you may be doing ‘too much, too soon’.

Further guidance on how much exercise you should do and how quickly to increase it can be provided by your physiotherapist.

The following graphs taken from the education leaflet titled ‘Managing My Patellofemoral Pain’  provide a great visualisation to guide you on returning to exercise.

Varied and rapid increases to exercise which can lead to development of, or ongoing knee cap pain.
Gradual and safe build up to exercise. The time to reach 100% of your goals will vary depending on each your characteristics including how long you have had pain for.

Supporting articles

Barton 2016. ‘Managing My Patellofemoral Pain’: the creation of an education leaflet for patients.

Thijs 2008. Gait-related intrinsic risk factors for patellofemoral pain in novice recreational runners.

Van Tigglen 2009. Delayed vastus medialis obliquus to vastus lateralis onset timing contributes to the development of patellofemoral pain in previously healthy men: a prospective study.



Try out this quiz to test your knowledge about knee cap pain!