Knee Osteoarthritis
The most common arthritis: knee cartilage and bone change over time, causing pain and stiffness. Not simple “wear and tear”: joints are living tissue, and moving usually makes them feel better.
The knee osteoarthritis ladder
Start at the bottom, climb only if you need to. Steps 1 and 2 are the real treatment at every stage, even if you also need the others.
- Step 1 · Self-careExercise and strengtheningLeg strengthening plus walking, cycling or water exercise, most days.
- Works
- Pain down about 13 points out of 100 vs no exercise; about as much as anti-inflammatory tablets, without the side effects
- Cost
- Free, or about $5–20 a session for a pool or gym
- How long
- 6–12 weeks to feel it; keep going for life
- Watch for
- Some soreness is normal. Fine if it settles within 24 hours.
Resting a sore knee feels logical. Unfortunately, knees prefer movement.
- Step 2 · Self-careWeight loss, if above a healthy weightEvery kilo off is several kilos less load on the knee with each step.
- Works
- Losing about 10% roughly halved pain in an 18-month trial (diet plus exercise); 5% noticeably eases pain
- Cost
- Free; weight-loss medicines such as semaglutide are private scripts, often several hundred dollars a month
- How long
- Months
- Watch for
- Weight-loss medicines: nausea, constipation; not in pregnancy.
Your knees do the maths on every staircase.
- Step 3 · PharmacyAnti-inflammatory gel (diclofenac or ibuprofen)Rubbed on the knee, up to 3 or 4 times a day.
- Works
- about 1 in 10 more people get good relief than with a dummy gel; far fewer side effects than tablets
- Cost
- About $15–30 a tube
- How long
- 2 weeks to judge; use as needed
- Watch for
- Skin redness or itch.
Best first painkiller for knees. Paracetamol does very little.
- Step 4 · PharmacyAnti-inflammatory tablets, short termIbuprofen or naproxen, or celecoxib on prescription, at the lowest dose for the shortest time.
- Works
- Pain down about 1 point out of 10 more than a dummy treatment, short term; useful for flares
- Cost
- Pharmacy about $5–15; celecoxib under the $25 PBS co-payment
- How long
- Days to a couple of weeks
- Watch for
- Stomach bleeds, kidney and heart risks. Not safe for many people: check with your GP or pharmacist.
A flare tool, not a lifestyle.
- Step 5 · Allied healthPhysio, exercise physiology or a GLA:D programA tailored strengthening plan, or a structured group program (about 6 weeks, run by trained physios) that builds skills and confidence.
- Works
- Moderate drop in pain at 3 months, mostly kept at 12 months (GLA:D Australia data, no comparison group); better function
- Cost
- About $90–130 a session; Medicare rebates with a GP care plan. GLA:D about $400–700 for the program
- How long
- 6–8 weeks of sessions, then keep going at home
- Watch for
- Choose someone who gets you moving, not just massaged.
Paying someone to make you do squats is surprisingly good value.
- Step 6 · ProcedureSteroid injectionAn injection into the knee for a bad flare.
- Works
- Pain down about 1 point out of 10 vs a dummy treatment; fades over 6 weeks, gone by 6 months
- Cost
- From bulk-billed to a few hundred dollars, depending on the clinic
- How long
- Relief for weeks
- Watch for
- Not a long-term fix. Repeated injections may harm the joint. Rare infection.
A pause button, not a fix.
- Step 7 · SpecialistKnee replacementFor severe pain and disability despite at least 3 months of good non-surgical care.
- Works
- About 85 in 100 improve meaningfully at 1 year (vs 68 in 100 with exercise program alone); about 1 in 5 have ongoing pain
- Cost
- Free in the public system (expect a wait); private out-of-pocket costs vary from hundreds to several thousand dollars
- How long
- Months of rehab
- Watch for
- Clots, infection, stiffness. Being fitter beforehand helps recovery.
The top rung. The exercises on rung 1 still come with you.
Save your money
Popular, heavily marketed or often asked about, but the evidence is weak or says no.
- Glucosamine and chondroitinNo better than a dummy treatment in good-quality studies. A pricey monthly habit with nothing to show for it.
- Hyaluronic acid (“gel”) injectionsNo better than a dummy treatment in good-quality studies, and often hundreds of dollars a course.
- PRP and stem cell injectionsSmall, low-quality studies; a large good trial of PRP found no benefit over a dummy treatment. Stem cells can cost thousands with no good evidence at all.
- Arthroscopy (“clean-out”)No better than exercise or sham surgery for arthritic knees, with all the risks of an operation.
- OpioidsLittle extra pain relief over anti-inflammatories, with more side effects and a real risk of dependence.
- MRI scansRarely needed. Most knees over 50 show “damage” on MRI, painful or not, and the scan rarely changes treatment.
What you can do
- Aim for 150 minutes of activity a week. On bad days, do less rather than stopping.
- Supportive shoes; a walking stick in the opposite hand takes load off the knee.
- Follow our knee exercise handout: one printable page with sets and progressions.
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.
Common questions
Is exercise safe with knee arthritis?
Yes. It is the most effective treatment at every stage, easing pain about as much as anti-inflammatory tablets. Some soreness is normal, and pain that settles within 24 hours is OK.
Do knee injections work for osteoarthritis?
Hyaluronic acid (“gel”) and PRP injections are no better than a dummy treatment in good-quality studies. A steroid injection can ease a bad flare for a few weeks, but isn’t a long-term fix.
Does glucosamine help knee arthritis?
No. Glucosamine and chondroitin are no better than a dummy treatment in good-quality studies.
When should I consider a knee replacement?
When pain and disability are severe despite at least 3 months of good non-surgical care. Most people have much less pain afterwards, but about 1 in 5 still have some ongoing pain.
What does knee arthritis feel like?
An ache in the knee that’s worse with walking, stairs or kneeling, stiffness after sitting, and sometimes swelling, creaking or the knee giving way. Morning stiffness usually lasts less than half an hour.
Is walking good for knee arthritis?
Yes. Walking and strength exercises reduce pain and improve function about as much as anti-inflammatory tablets, without harming the joint. Some aching during or after exercise is fine if it settles within a day.
How long does a knee replacement last?
Large studies show about 9 in 10 knee replacements are still working after 15 years, and about 8 in 10 after 25 years.
Helpful resources
- Knee osteoarthritis exercise handoutPrintable, one page, with sets and progressions. Free, from us.
- GLA:D AustraliaStructured 6-week education and exercise program for knee and hip arthritis, run by trained physios. Paid; check your health fund. Australia.
- MyOA (Arthritis Australia)Trusted information, symptom tracking and goal-setting tools for osteoarthritis. Free, Australia.
- Arthritis UK: Knee pain exercise sheetPrintable stretches and strengthening exercises for sore knees. Free, UK.
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)
- Cochrane: Exercise for knee osteoarthritis (2024)
- JAMA: IDEA trial of diet and exercise for knee osteoarthritis (2013)
- Cochrane: Topical NSAIDs for chronic musculoskeletal pain (2016)
- BMJ: Short-term NSAIDs for knee osteoarthritis pain, meta-analysis (2004)
- Osteoarthritis and Cartilage Open: GLA:D Australia program evaluation (2021)
- Cochrane: Steroid injections for knee osteoarthritis (2015)
- NEJM: Knee replacement vs non-surgical treatment (2015)
maladywise.com/knee-oa/