Of all the parts of your body, your knee joint is one of the most vulnerable to damage and pain. And no wonder. Your knees have to support the full weight of your body as well as any extra force created by movements such as running and jumping. So it should be no surprise that many people experience knee pain, particularly those who are overweight and those who do a lot of sports. Knee pain, says the NHS, also becomes more likely as you get older.
One of the most common causes of aching pain around the knee is patello-fermoral pain syndrome – also called anterior knee pain or, as many people know it, runner’s knee. As its name suggests, runner’s knee is common among athletes and sports people. But it can also affect anyone who spends a lot of time bending their knees. According to private health care provider Bupa, one in four people who are seen at sports medicine clinics have runner’s knee (i). It also seems to be more common in women.
You know you may have runner’s knee when you’re affected by pain and sometimes also swelling behind or around the kneecap. The pain – which can be sharp and sudden or dull and long lasting – can become worse when you walk downhill or downstairs, and you may also experience unpleasant popping, clicking or grinding sensations in your knee. You may even have pain while sitting too, and occasionally your knee may suddenly give way or buckle when you put your weight on it.
What causes runner’s knee?
The patello-fermoral joint is the joint that connects the knee cap (patella) and thigh bone (femur). The knee cap sits in a groove on the end of the thigh bone, and muscles connected to the knee cap help stabilise it and keep it running smoothly within the groove. But when the knee cap doesn’t run smoothly within the groove – a problem known as patella mal-tracking – the result is pain, particularly while you’re doing things such as walking, climbing, running, kneeling, squatting or jumping.
There are several reasons why this mal-tracking may happen:
If you injure your knee in a fall, for instance, or you have surgery that affects any of the structures that stabilise the knee cap, it can cause patella mal-tracking.
Repeated bending of the knee can stress and irritate the nerves of the kneecap, and may also stretch the tendons in the knee too much (tendons connect your muscles to your bones). Both of these things can cause runner’s knee
Suddenly increasing the load on your knee is also linked to runner’s knee. For instance, this may happen when you start exercising too vigorously when you’re not used to being very active, or when you increase the amount of time you spend exercising or the intensity at which you exercise. Some fitness experts also think not spending enough time recovering from a training session could increase your risk of knee pain.
The natural position of your hip, knee and feet bones can cause patella mal-tracking if any of these bones are slightly misaligned (out of their correct position). This means your weight won’t be evenly distributed, which can put too much pressure on certain joints, including the kneecap, and force the kneecap to sit incorrectly within the femoral groove. Other body issues that can increase your risk of runner’s knee include:
Worn cartilage in the knee joint (as this reduces shock absorption)
Tight hamstring muscles (the muscles at the back of your thigh)
Weak quadriceps muscles (the muscles in the front of your thigh) or weak hip muscles
Poor lower leg movement (biomechanics)
Hypermobile feet (when the joints in and around the feet are hyper flexible, which can make them unstable)
Flat feet (fallen arches)
Overpronation (when your foot rolls inwards excessively)
Some physiotherapists also believe wearing the wrong type of trainers can lead to runner’s knee. When you’re working out you need the right type of footwear to support the way you move naturally. This is why experts often recommend having an assessment of the way you walk and run at a specialist runner’s store. This can help you identify which type of trainer would support you best. Not replacing your trainers as often as you need to can also lead to problems, as trainers don’t last forever and can lose their support and shock absorption capabilities over time. How often you should replace them will depend on how much you use them – most experts say you should get a new pair every 300 - 500 miles.
How is runner’s knee treated?
According to the NHS, runner’s knee can normally be treated easily using ordinary painkillers, an ice pack and rest. An ice pack can help ease pain and swelling – ice your knee for 20 minutes every three to four hours for a couple of days or until the pain has subsided. If your knee has any swelling, an anti-inflammatory may be the best type of painkiller to take, plus you could try natural supplements that have an anti-inflammatory action, such as turmeric or a high-strength fish oil supplement.
If you’re a runner, cut down on your mileage at the first sign of any knee pain, don’t use routes where you have to run downhill or down steps, and avoid excessive bending of your knees whenever possible. Also try to avoid sitting and/or standing for extended periods.
However, if you’re training for an event, you could consider doing an alternative type of activity that doesn’t aggravate your symptoms, at least until the irritation has subsided – swimming laps, for instance, can help you to maintain your cardiovascular fitness while at the same time supporting your knee joints. Also, when you’ve recovered sufficiently to start doing some light running, try to avoid running on hard surfaces such as concrete.
Compressing the knee joint by strapping it with an elastic bandage or using a sports wrap or knee brace may give the joint extra support while it’s healing. You may also want to consider seeing a sports medicine professional such as a physiotherapist, who can advise you about stretching and strengthening exercises that could help get your knee back to normal. A physiotherapist can also assess any biomechanical problems you may have developed. Any remedy may include improving the strength of certain muscles – glutes (the muscles in your hips) or quadriceps, for instance – to help prevent the problem happening again.
If your problem is in your feet, and wearing the right type of trainers doesn’t go far enough to address it, you may need orthotics. These are special insoles that are placed inside your shoes to help support your arches – you can buy them over the counter or get them custom made by a podiatrist.
As a last resort, you may be advised to have surgery, especially if you’ve tried everything else without much success. This can help correct imbalances in the muscles, bones and joints that cause mal-tracking of the knee cap. However, surgical success rates are relatively low.
How long will recovery take?
There’s no hard and fast rule as to how soon you’ll recover from runner’s knee. Most people are thought to get better with simple treatments such as physiotherapy (according to the NHS most people see up to 80 percent improvement if they have physio). But it can take up to six months before you’re fully recovered – and during that time you won’t be able to train as much as you used to.
You’ll know you’ve recovered sufficiently when you can fully bend and straighten you knee without pain, when you can jump or spring without feeling pain and when your injured knee is as strong as your uninjured knee.
The bad news, however, is that experts believe the symptoms of runner’s knee persist in 25 percent of people for up to 20 years (ii). If you’re among them, you may experience sudden and occasional flare-ups of knee pain. When this happens, use ice or heat and take painkillers if necessary, until you can get back to your normal activities again.
Keri Filtness has worked in the Nutrition Industry for 19 years. She is regularly called upon for her professional comments on health and nutrition related news. Her opinions have been featured by BBC3, Prima, Vitality, The Mirror, Woman’s Own and Cycling Weekly, amongst others. She has also worked one to one with journalists, analysing their diets and health concerns and recommending changes and additions, where appropriate.