What your knee pain might be telling you

Last updated:
Our knees are under a lot of strain every day from carrying our body weight. As our knees are naturally more vulnerable to damage than other parts of our body, we’re all prone to a bit of wear and tear. Here are 7 common causes of knee pain.

Need to speak to a GP today?

Book appointment

Research shows that nearly half of people aged 50+ have had knee pain in the previous year, and out of these, a third had spoken to a GP about their symptoms in the same 12 months. Knee pain is very common in people of all ages.

Knee pain can be commonly caused from an injury like a ruptured ligament, torn cartilage or bleeding in the joint – especially if you play lots of high-impact sports like tennis or football. There are several different underlying causes of knee pain too, which can be harder to diagnose.

‘As you get older, you’re more likely to experience mild knee pain symptoms from daily wear and tear,’ says Dr Rhianna McClymont, Lead GP at Livi. ‘Usually this is nothing to worry about – but if you notice the pain is getting worse, affecting your daily activities or you have other persistent symptoms, speak to a doctor.’

What knee pain symptoms should I look out for?

On top of injuries and age-related conditions, there are many causes of knee pain and knee inflammation. The symptoms you experience will vary depending on the cause.

Here are some common symptoms to look out for, and reasons most people speak to a doctor about getting knee pain treatment.

  • Stiffness
  • Swelling
  • Redness or warm to touch
  • Knee clicking or popping
  • Unable to straighten your knee
  • Knee feeling unstable or giving way
  • Locking of the knee joint

What are the common causes of knee pain?

Sustaining an injury is by far the most common and often unavoidable reason for experiencing knee pain and swelling.

A meniscus tear is a typical knee injury, particularly for athletes or people who play contact sports. The meniscus is a piece of cartilage that cushions your femur (thighbone) and tibia (shinbone). There are two in each knee joint.

‘Whether your injury is a sprain, torn ligament or menisci, dislocation or broken bone, you’ll usually get some fairly instant knee pain, swelling and tenderness. And the knee pain will be more intense depending on how badly you’re injured,’ explains Dr Rhianna McClymont.

Underlying conditions usually cause knee pain to come on more gradually instead. While this list is by no means exhaustive, GPs tend to see the following conditions causing chronic knee pain.

1. Osteoarthritis

This is the most common form of arthritis, and one that usually develops with old age or overuse of joints. It causes damage to the articular cartilage, which you need to protect your knees. Osteoarthritis of the knee can cause swelling of the tissues around your joints too. Although there’s no cure, a doctor can recommend ways to reduce the strain on your knees which may improve your symptoms.

2. Rheumatoid arthritis

Rheumatoid arthritis can develop at any age and can affect almost every joint in your body. The autoimmune condition can cause knee pain and swelling over a long period of time. There may not always be an obvious trigger for this type of knee pain and you may experience flare ups even after resting.

3. Gout

Symptoms of gout include very sudden and severe pain in your joints, commonly affecting the big toe as well as the knee joint. On top of getting sharp pain, the affected area usually becomes swollen, red and tender to touch.

4. Infection (septic arthritis)

A common infection of the knee joint is septic arthritis. If you’re not sure what’s causing your knee pain, and your knee is very swollen and hot, it could be an infection.

Other symptoms of an infection include having a fever and feeling generally unwell. It’s important to go straight to A&E if you think this might be the case.

5. Tendonitis

Tendonitis in the knee happens when the tendons around your knee become inflamed. This kind of knee inflammation can be brought on by lots of intense exercise, especially jumping and squatting (common in sports like basketball and tennis). As with other conditions, symptoms may include a swollen knee that’s warm and tender to touch.

6. Bursitis

If you have particular knee pain on bending (that gets worse when you kneel or bend down), it could be bursitis. This knee inflammation is caused by repetitive movement in your knee, or kneeling for a long period of time and is sometimes referred to as ‘housemaid’s knee’. Bursitis can lead to fluid building up over the knee joint which causes further swelling.

7. Osgood-Schlatter’s disease

Unlike many knee conditions, this one is much more common in teenagers and young adults who play a lot of sports. The disease causes swelling and tenderness just underneath the knee (in the bony part).

Self help for knee pain

‘When knee pain is severe, limiting your activities or has persisted for a long time it’s best to speak to your own doctor for a diagnosis and for advice on the best knee pain treatment for your condition,’ says Dr Rhianna McClymont.

‘In the meantime, there’s a few simple ways you can look after your knees, prevent any further damage and help manage your symptoms.’

  • Rest your knee to reduce any repetitive strain and give yourself time to heal – a really important one if you’re getting knee pain from exercise, or knee pain from walking

  • Ice your knee to minimise swelling, which works well for acute and chronic knee conditions

  • Protect your knee from further trauma with knee padding or a splint, to help keep your knee straight and avoid knee pain when walking up stairs (if you can’t use a lift instead!)

  • Elevate your knee as much as you can to help reduce swelling and minimise knee pain from sitting

  • Compress your knee with a brace or wrap to reduce knee inflammation - speak to a doctor if you’re not sure how to apply correctly or whether this is suitable for your knee

When to speak to a doctor

For most people, minor knee problems should begin to settle within 6 weeks.

But it’s always best to speak to a GP if your knee pain gets worse, or your knee starts to lock or give way, and hurts when you’re not moving it. If you’re not able to extend or bend your knee at all, it needs to be checked out as soon as possible. Look out for any deformities or lumps around the knee joint too.

A GP can make a referral for you to see a specialist for further investigation or treatment.

Phone 111 if you have difficulty putting any weight on your sore leg or your knee becomes immediately swollen after an injury.

This article has been medically reviewed by Dr Rhianna McClymont, Lead GP at Livi.

Speak to a GP about knee pain

Don’t suffer with distressing knee pain and get medical advice from a GP today.

Book an appointment

Get expert advice and tips

Sign up to get the best of our health content delivered right to your inbox.