Knee osteoarthritis: staying active and managing pain

What knee osteoarthritis is

Osteoarthritis (OA) affects the whole joint: the cartilage covering the ends of the bones, the bone underneath, the joint lining and the ligaments and muscles around it. Joints are constantly repairing themselves. In osteoarthritis, that repair process becomes less efficient, leading to changes such as thinning cartilage, bony outgrowths and some swelling.

Wear and tear is a misleading phrase. It suggests the joint is gradually being ground away with use and that activity makes it worse. In fact, well-dosed activity and strength training help the joint, and many people with changes on an X-ray have little or no pain, while others with small changes have a lot. The amount of pain does not simply reflect the amount of damage.

Who gets it

Knee OA becomes more common from about 45 onwards and is more common in women. Other risk factors include a previous knee injury such as a ligament or meniscus tear, higher body weight, family history, and jobs involving a lot of kneeling or heavy lifting.

Recreational running is not generally linked with a higher risk of knee OA, and many runners with knee OA can keep running with sensible adjustments. What matters most is matching load to what the knee currently tolerates.

A common story is someone in their 50s who has always been active, notices their knees aching after a long walk or a gym session, and starts to worry they should stop. In most cases the opposite is true: the right kind of activity is part of the treatment.

Typical symptoms

• Pain with activity, such as walking, stairs, squatting or kneeling
• Morning stiffness that usually eases within 30 minutes
• Stiffness after sitting, easing as you get going
• Grinding or crackling sounds, which are common and not a problem on their own
• Swelling after more activity than usual
• Reduced range of movement or a feeling of weakness

Symptoms often fluctuate, with good weeks and flare-ups. Flares commonly settle over a few days to a couple of weeks and do not usually mean the joint has been damaged further.

What a physio assessment looks at

UK guidance allows osteoarthritis to be diagnosed without an X-ray in people aged 45 or over who have activity-related joint pain and morning stiffness lasting no longer than about 30 minutes. Your physio will ask about your symptoms, general health, activity and goals, then assess movement, swelling, strength, balance and how you walk, squat and use stairs.

They will look for other causes of knee pain, check your hip, and discuss what matters most to you, whether that is walking the dog, playing with grandchildren, getting back to the gym or continuing to train for events.

What usually helps

UK guidance recommends exercise as a core treatment for everyone with osteoarthritis, including local muscle strengthening and general aerobic fitness, alongside education and weight management where needed. Research consistently shows that exercise reduces pain and improves function in knee OA, with benefits often noticeable within 6 to 12 weeks.

Strength training for the quads, hips and calves is particularly useful. Exercises like the leg press, sit to stand, step-ups and squats to a comfortable depth can all be part of a plan. Our guide to strength training over 50 covers getting started safely. Manual therapy can be used alongside exercise for some people.

For people carrying extra weight, even modest weight loss reduces load on the knee and can make a noticeable difference to pain. Our guide to losing weight with knee pain covers exercise options that go easy on the joints. Pain relief options, including topical anti-inflammatory gels, are worth discussing with a pharmacist or GP. Keyhole washout surgery is not recommended for knee OA, and knee replacement is considered when symptoms remain severe despite good non-surgical care.

What you can start with at home

1. Sit to stand from a chair, 3 sets of 10, lowering the chair height over time.
2. Straight leg raises, 3 sets of 10 to 15 each side.
3. Step-ups onto a low step, 3 sets of 8 to 10 each side.
4. Calf raises holding a worktop, 3 sets of 15.
5. Walking or cycling most days, starting with what is comfortable and adding a few minutes each week.

Aim for strengthening two or three times a week and some form of aerobic activity on most days, in line with the UK Chief Medical Officers' guidelines of 150 minutes of moderate activity a week plus strength work on two days. Build up gradually.

If a session flares your knee, it is a signal to adjust the dose rather than stop exercising. Reduce the range, load or number of sets for a few days, then build back more gradually.

Long-term outlook and when to get help

OA is a long-term condition, but it does not inevitably get worse, and many people improve their symptoms significantly with exercise and weight management. The on-site physio at Lycan Strength can build a plan around your goals, with 20% off for members; book a physio appointment online.

• Go to A&E if the knee becomes hot, red, very swollen and painful, especially with a fever.
• Go to A&E if you cannot bear weight after a fall or injury.
• See a GP or physio promptly if the knee locks, keeps giving way or swells suddenly.
• Call NHS 111 or see a GP urgently for a swollen, warm, painful calf. Call 999 with chest pain or breathlessness.
• See your GP if you have unexplained weight loss, severe night pain or feel generally unwell.

Questions