Runners Knee

Written By: Chloe Wilson, BSc(Hons) Physiotherapy
Reviewed by: KPE Medical Review Board

Runners Knee: Everything you need to know including causes, symptoms, diagnosis, treatment and prevention

Runners Knee is one of the most common causes of front knee pain and accounts for approximately 25% of all knee injuries seen in sports injury clinics. 

Runners Knee is also known as "Patellofemoral Syndrome" or "Anterior Knee Pain" and refers to pain under and around the kneecap.

It is caused by a problem with the way the knee cap moves resulting in friction on the back of the knee and is often linked with weak VMO muscles.

Symptoms tend to come on gradually and come and go depending on your activities. Runners Knee is not the only cause of knee pain from running and despite the name, it affects both active and sedentary people e.g. office workers. 

Here we will look at the causes, symptoms, treatment options and recovery process from Runners Knee, frequently asked questions such as can I run on runners knee, as well as other knee conditions commonly misdiagnosed as Patellofemoral Syndrome.

What Is Runners Knee?

Runners Knee Biomechanics: The patella rests in a small groove at the end of the femur "trochlear groove". As you bend and straighten your knee, the patella slides up and down within the groove.

In Runners Knee, there is a problem in the way the patella (kneecap) moves. This places extra stress on the cartilage, resulting in front knee pain.

The kneecap sits in a groove, known as the patella or trochlear groove, at the front of the knee on the femur, thigh bone

It can glide, tilt and rotate upwards, downwards and sideways in this groove.

The knee cap is lined with very thick cartilage to help protect it from the large forces that go through the bone.

There are a number of things that stop the patella from moving properly, all of which increase the forces and friction going through the kneecap, causing patella femoral syndrome. 

Causes Of Runners Knee

Common causes of runners knee include:

  • Muscle Weakness: Weakness in the muscles reduces the support around the knee causing more weight to go through the kneecap. Also, if the muscles on one side of the knee are weak while the muscles on the other side are too strong, the kneecap will shift slightly to one side in the groove, resulting in friction

  • Muscle Tightness: If the muscles around the kneecap are tight, they will pull it up slightly and possibly slightly to the side, increasing knee cap pain and friction

  • Abnormal Foot Position: An abnormal foot position, such as flat feet, causes the foot to roll inwards which alters the way the forces go through the knee, increasing pressure on the kneecap

  • Increased Q Angle: This refers to the angle of the thigh bone. An increase in the Q angle puts more strain on the kneecap

  • Anatomy: There can be a problem with the shape of the groove and/or kneecap which result in the two not lining up properly which can restrict the movement and cause friction, predisposing you to patellofemoral syndrome

Symptoms of Patellofemoral Syndrome

Runners Knee usually comes on gradually – it is not triggered by a specific incident. People describe it as an ill-defined ache around the kneecap, particularly underneath and at the sides of the patella.

This helpful video from ClearDoc explains what is going on with the patella in patellofemoral syndrome.

There may also be grinding/grating sounds associated with leg movement in patellofemoral syndrome – this is known as crepitus and is caused by friction on the kneecap. Sometimes, there can also be some front knee swelling.

Runners knee pain tends to come and go rather than being constant but is usually worse with:

  • Prolonged Activity: e.g. running long distances, sports, skiing especially when going downhill
  • Stairs: especially coming downstairs
  • After Sitting for Long Periods: e.g. at the cinema, office workers, driving long distance.  The knee tends to be sore when you first get up and then eases with movement

How To Treat Runners Knee

Treatment for Runners Knee aims to reduce the kneecap pain and swelling, and address any muscle imbalance in the leg. The most common treatments for patellofemoral syndrome are:

#CommissionsEarned from Amazon on qualifying purchases

1. Strengthening Exercises

Strengthening exercises are a great way to treat Runners Knee

Strengthening exercises are key with patellofemoral pain syndrome as people with Runners Knee often have weak glutes (buttocks) and quads muscles. Strengthening these muscles will reduce the weight going through the knee and thus reduce knee pain.

In the knee strengthening section you will find a whole range of exercises that can help improve strength and stability and thus reduce runners knee pain.

Also, exercises that specifically target the muscles that control the kneecap make a massive difference, improving the way the kneecap glides in the patellar groove- see the kneecap exercises section for more information.

2. Stretches

Another important part of runners knee treatment is stretches. Reducing any muscle tightness through simple stretching exercises will also improve how the knee cap glides in the patellar groove reducing the friction on the kneecap.

Any tightness around the kneecap muscles will pull it slightly out of place resulting in increased friction and pressure on the knee cap, leading to runners knee.

Visit the knee stretches section for simple tests to see if muscle tightness is causing your patellofemoral syndrome pain and exercises that can help.

3. Knee Braces

Knee braces can be helpful with patellofemoral pain syndrome

Another useful treatment tool with runners knee is a knee brace. Braces can help to improve the support around the knee and the position of the patella reducing the pain associated with patellofemoral syndrome.

There are a whole range of styles, but generally the best ones for Runners Knee have a hole at the front to prevent any extra pressure on the kneecap. 

In the Knee Brace Guide section you can find loads of advice on how to find the right brace for you.

4. Orthotics

If your runners knee is linked in part with alltered foot biomechanics, then using orthotics can really help. Orthotics are special insoles that can be worn on your shoes to correct your foot position and Q angle and therefore reduce the forces going through the kneecap.

Your doctor can refer you to an orthotist to get your feet assessed and provide appropriate insoles or check out our favorite orthotics on our sister site.

5. Rest and Pacing

Runners Knee often develops after an increase in activity levels. It may be advisable to rest for a few days to let your knee pain settle down, and then gradually build up the amount of exercise you do, or switch to non-impact exercise such as swimming.

Remember, pain doesn’t always come on during an activity, it often develops later that day or overnight, so start slowly and gradually increase.

6. Regular Ice 

Using ice after activity can really help to reduce patellofemoral syndrome pain and swelling. It helps to reduce any inflammation and bleeding in the joint which helps to reduce pain and speed up healing.

Visit the Ice Treatment section for advice on how to safely and effectively use ice, and the ice wrap section for our top tips on the best ways to apply ice.

7. Avoid Prolonged Postures

If your runners knee pain comes on after sitting for long periods, try to avoid keeping your leg still.

At work, get up and have a little walk around every thirty minutes or so or if that’s not possible, gently move your leg backwards and forwards a few times. Another thing that can help reduce runners knee symptoms is to use a standing desk so you're not sitting all day.

This keeps the joint loose and lubricated which can help reduce patellofemoral syndrome pain.

8. Painkillers

Over the counter painkillers e.g. paracetamol/acetaminophen and non-steroidal anti-inflammatories e.g. Advil/Ibuprofen can be useful to reduce the pain associated with Runners Knee. Always consult your doctor before taking medication.

9. Surgery

It is very rare that patellofemoral syndrome requires surgery. However, if the above treatments do not work surgery may be indicated to release tight structures around the knee or to remove bits of bone that are irritating the knee cap. This is known as lateral release surgery.

The correct treatment will depend on the cause of your patellofemoral syndrome, so it is always advisable to see your Health Professional who can accurately assess what is causing your problem.

Runners Knee Recovery

It can take anywhere from six weeks to six months to recover from Runners Knee depending on how quickly you start treatment and how diligent you are.

It usually takes a few weeks of doing strengthening and stretching exercises for muscle strength and length to improve, so don’t give up. Also, don’t be tempted to increase your activity levels too quickly. Pace yourself so as not to aggravate your knee - check out our top tips on exercising.

If you want to keep exercising, try lower impact work such as swimming and cycling. If you do want to run, make sure you have good running shoes and try to avoid running on concrete as the hard surface puts more strain through the knee.

Common Misdiagnosis

There are a number of other conditions that cause front knee pain and Runners Knee is often incorrectly diagnosed as:

Whilst these conditions may have similar presentations, there are important subtle differences to patellofemoral syndrome so do check out these other sections.

Want To Know More?

People often have a lot of questions about Runner's Knee. In the Patellofemoral Syndrome FAQ's section, you will find answers to the most commonly asked questions such as, How do I know if I've got it? Do braces really help? And can I still run?

If Runners Knee isn't sounding quite like your problem and you want help working out what is wrong with your knee and why you have pain, visit the knee pain diagnosis section.

You may also be interested in the following articles:

Page Last Updated: 06/02/24
Next Review Due: 06/02/26

Related Articles

Knee Pain From Running: How To Get Back To Doing What You Love

Knee Pain Running
July 7, 2023

Knee Symptoms: What Is Wrong With My Knee?

Knee Symptoms
February 2, 2023

Theraband exercises for legs

Resistance Band Exs
December 7, 2023