Knee Osteoarthritis
The most common type of arthritis. The cartilage and bone in the knee change over time, causing pain and stiffness, often worse after rest or with activity. It isn’t simply "wear and tear": joints are living tissue, and staying active usually makes them feel better, not worse. Scans are rarely needed to diagnose it.
Treatment options
Ratings show how strong the research is.
- Strong evidenceExercise and strengtheningThe most effective treatment at every stage. Leg-strengthening plus walking, cycling or water exercise reduce pain and improve function. Some soreness is normal and not harmful. A physio or exercise physiologist can tailor a program.
- Strong evidenceWeight loss, if above a healthy weightLosing 5 to 10% of your body weight noticeably reduces knee pain, and more loss helps more. GLP-1 medicines (such as semaglutide) can help if suitable: ask your GP.
- Strong evidenceAnti-inflammatory gelSuch as diclofenac or ibuprofen gel rubbed on the knee. The first medicine to try, with far fewer side effects than tablets.
- Moderate evidenceEducation and exercise programsStructured programs such as GLA:D (about 6 weeks, run by trained physios) teach you how to manage your knee and build confidence to stay active.
- Moderate evidenceAnti-inflammatory tablets, short termSuch as ibuprofen, naproxen or celecoxib. Use the lowest dose for the shortest time. Not safe for many people with kidney, heart or stomach problems: check with your GP or pharmacist.
- Moderate evidenceDuloxetineA prescription medicine that can modestly ease long-term pain.
- Moderate evidenceKnee replacementFor severe pain and disability despite at least 3 months of good non-surgical care. Most people have much less pain afterwards, but some still have ongoing pain.
- Limited evidenceParacetamolOnly a small benefit. May suit people who can’t take anti-inflammatories.
- Limited evidenceSteroid injectionCan ease a bad flare for a few weeks. Not a long-term fix, and repeated injections may harm the joint.
- Not recommendedHyaluronic acid ("gel") or PRP injections, glucosamine, chondroitinNo better than placebo in good-quality studies, and costly.
- Not recommendedArthroscopy ("knee washout" or "clean-out")No lasting benefit, and carries surgical risks.
- Not recommendedOpioidsSuch as oxycodone or tramadol. Harms outweigh the benefits.
What you can do
- Keep moving: aim for 150 minutes of activity a week. Pain that settles within 24 hours is OK. On bad days, do less rather than stopping.
- Wear comfortable, supportive shoes. A walking stick in the opposite hand takes load off the knee.
- Ask your GP about a care plan for Medicare-subsidised physio visits.
See your GP if
- Pain stops you sleeping, working or doing what you enjoy
- Your knee locks, gives way or keeps swelling
- You need anti-inflammatory tablets most days
- Pain keeps getting worse despite 3 months of exercise and weight management
See a doctor the same day for a hot, red, swollen knee, especially with fever, or if you suddenly can’t put weight on your leg.
Evidence and more information
- ACSQHC: Osteoarthritis of the Knee Clinical Care Standard (2024)
- RACGP: Guideline for the management of knee and hip osteoarthritis
- NICE: Osteoarthritis diagnosis and management (2022)
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