What is knee arthritis?

Knee arthritis is joint damage in the knee — most often osteoarthritis — causing pain when standing, walking or climbing stairs, stiffness after rest, and swelling. NICE recommends exercise and weight loss as first-line treatment; every 5 kg lost cuts knee load by roughly 20 kg.

Last updated 2026-07-01. This is general information, not a substitute for personalised medical advice.

Frequently asked questions

What's the best exercise for knee arthritis?

Quadriceps strengthening (straight-leg raises, wall sits) plus low-impact aerobic (cycling, swimming). 3-5 sessions a week for 8+ weeks shows meaningful pain reduction.

Should I use a walking stick?

Use it in the opposite hand to the painful knee — this reduces load by up to 25%.

Sources and further reading

  • NHS: Arthritis overview
  • NICE NG226: Osteoarthritis in over 16s