Runners Knee is one of the most common causes of pain at the front of the knee and accounts for approximately 25% of all knee injuries seen in sports injury clinics.
It is also known as "Patellofemoral Pain Syndrome" or "Anterior Knee Pain" and refers to pain under and around the kneecap.
Despite the name, it affects both active and sedentary people eg office workers. It is not the only cause of knee pain from running and is commonly misdiagnosed as Chondromalacia patella, Iliotibial Band Syndrome or Patellar tendonitis.
Here we will look at the symptoms of Runners Knee, what causes it, what activities aggravate it, how to treat it and the recovery process.
Runners Knee usually comes on gradually – it is not triggered by a
specific incident. People usually describe it as an ill-defined ache
around the kneecap, particularly underneath and at the sides of the
There may also be a grinding/grating sounds associated with
leg movement in patella femoral syndrome – this is known as crepitus and is caused by friction. Sometimes, there can also be some mild swelling.
The pain tends to come and go but is usually worse with:
1) Prolonged Activity eg running long distances, sports, skiing especially when going downhill
2) Stairs: especially coming downstairs
3) Sitting for long periods eg at the cinema, office workers, driving long distance.
The exact cause of Runners Knee is unknown but it is thought that a problem in the way the patella (kneecap) moves is the main cause. The kneecap sits in a groove on the femur (thigh bone) at the front of the knee. It can glide, tilt and rotate, upwards, downwards and sideways in this groove.
There are a number of factors that stop the patella from moving properly in the groove, all of which increase the forces and friction going through the kneecap, causing patella femoral syndrome:
1) 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
2) Muscle Tightness: If the muscles around the kneecap are tight, they will pull the kneecap up slightly, and possibly slightly to the side, increasing knee cap pain and friction
3) 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
4) Q Angle: This refers to the angle of the thigh bone. An increase in the Q angle puts more strain on the kneecap.
5) 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.
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 patella femoral syndrome are:
People with Runners knee often have weak Glutes (buttocks) and Quads muscles. Strengthening these muscles will reduce the weight going through the knee. Visit the knee strengthening section for exercises that can help.
Also, exercises that specifically target the muscles that control the kneecap make a big difference, improving the way the kneecap glides in the patellar groove- see the kneecap exercises section for more information.
Reducing any muscle tightness will also improve how the knee cap glides in the patellar groove reducing the friction on the kneecap. Visit the knee stretches section for simple tests to see if muscle tightness is causing your pain
Braces can help to improve the support around the knee and the position of the patella reducing the pain associated with patella femoral syndrome. Visit the Knee Brace Guide to find the right brace for you
There 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
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
Using ice for 10 minutes after activity may help to reduce runners knee pain. Visit the Ice section for advice on how to safely and effectively use Ice therapy and the ice wrap section for the best ways to apply ice.
If your 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 30 minutes or so or if that’s not possible, gently move your leg backwards and forwards a few times. This keeps the joint loose and lubricated which can help reduce patella femoral syndrome pain.
Over the counter painkillers and non-steroidal anti-inflammatories eg Advil/Ibuprofen can be useful to reduce the pain associated with Runners Knee
It is very rare that Runners Knee requires surgery, but if the above treatments do not work, sometimes surgery is indicated to release tight structures around the knee or to remove bits of bone that are irritating the knee cap.
The correct treatment will depend on the cause of your patella femoral syndrome, so it is always advisable to see your Health Professional who can accurately assess what is causing your problem.
It can take anywhere from 6 weeks to 6 months to recover from Runners Knee. 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.
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.
There are a number of other conditions that cause front knee pain and Runners Knee is often incorrectly diagnosed as:
1) Chondromalacia Patella: where there are actually changes in the cartilage lining the kneecap
2) Jumpers Knee: irritation of the patellar tendon just below the knee
3) Iliotibial Band Syndrome: irritation of the ITB on the outer side of the leg
Whilst these conditions may have similar presentations, there are important subtle differences to patella femoral syndrome so do check out these other sections.
If you want help working out what is wrong with your knee and why you have pain, visit the diagnose your pain section