Joint injections in hip and knee osteoarthritis
The 60-second evidence answer on cortisone, gel injections, platelet-rich plasma and stem-cell injections — including the numbers, the costs and the 3-month rule before joint replacement.
Australian Knee Arthritis Clinical Care Standard 2024 aligned · Reviewed July 2026An injection may calm symptoms. It does not repair an arthritic joint.
All four verdicts, before you scroll
Costs are indicative only. Medicare eligibility, product prices and provider fees vary. Confirm before booking.
Cortisone, in full
Intra-articular corticosteroid
Celestone Chronodose · Kenacort-A40 · Depo-Medrol
“This may settle the pain quickly, but it is temporary — think weeks, not years. It will not repair the joint, and repeated injections are not a good long-term plan. If joint replacement may be close, tell your surgeon before having it.”
Yes — short term only.
Use as an adjunct for a painful flare when short-term relief may support movement, sleep or participation in an active management plan. It is not disease-modifying treatment.
- Onset may be within days.
- NICE describes short-term relief of about 2–10 weeks.
- The 2024 Australian Knee Arthritis Clinical Care Standard recognises intra-articular corticosteroid as a short-term add-on option.
- A Medicare-eligible image-guided service may be bulk billed at some Adelaide radiology sites — confirm eligibility and the site’s current policy.
- Serial-use cartilage signal: McAlindon (JAMA 2017), triamcinolone every 12 weeks for 2 years: cartilage change −0.21 mm vs −0.10 mm with saline, no significant pain advantage.
- Pre-arthroplasty infection: avoid injection into the operative joint within 3 months of hip or knee replacement — one meta-analysis reported OR 1.39 (95% CI 1.04–1.87) for periprosthetic joint infection inside this window.
- Septic arthritis: rare but serious.
- Post-injection flare may last 1–2 days.
- In diabetes, blood glucose may rise temporarily.
The 3-month rule
Document the drug, joint and date of every intra-articular injection. Avoid corticosteroid injection into the operative joint within 3 months of total hip or knee arthroplasty.
Gel injections, in full
Hyaluronic acid (“gel”) injections
Synvisc-One · Durolane · Monovisc · Euflexxa
“This is a laboratory-made version of one of the slippery substances in healthy joint fluid. It acts like a lubricant and cushion. It does not regrow cartilage. If it helps, the effect is usually slower than cortisone.”
Not recommended for routine knee arthritis care.
Average benefit in trials is not clinically useful, and treatment can be expensive. This is the current Australian position.
- In older trajectory literature, any reported response developed later than cortisone and could persist to about 24 weeks.
- It avoids corticosteroid exposure.
These points explain timing only; they do not override the current Australian recommendation.
- The 2024 Australian standard says do not offer gel injections routinely: average benefit is not clinically useful and treatment can be expensive.
- AAOS 2021 recommends against routine use; UK guidance also says do not offer.
- Some Adelaide providers bulk bill Euflexxa (medicine + image-guided procedure) for eligible Medicare patients; other brands or providers may charge privately.
- Jones Radiology’s Feb 2024 referrer sheet describes 3 CT-guided Euflexxa injections, 2 weeks apart, a separate referral each, bulk billed for Medicare card holders — confirm this remains current when booking.
- Light Radiology lists Euflexxa at Klemzig, Marion and Unley and states it bulk bills almost all procedures — confirm exact eligibility and out-of-pocket cost.
- Pseudoseptic inflammatory reactions are reported; true infection is rare.
When relief arrives — and how long it lasts
Text alternative: corticosteroid relief typically rises within days and declines over roughly 2–10 weeks. Any gel-injection response develops later and may persist to about 24 weeks. The vertical axis is qualitative — timing does not mean proven benefit, and gel injections are not recommended routinely for knee arthritis.
The expensive questions
PRP
“Platelet-rich plasma is made from your own blood. The best Australian trial found no meaningful improvement in pain or cartilage after 12 months, and the current Australian knee arthritis standard says not to offer it.”
- RESTORE (JAMA 2021, n=288): no significant difference in pain or medial tibial cartilage-volume loss at 12 months versus saline.
- Indicative cost $300–$800 per injection, no Medicare rebate.
- Preparation methods, platelet concentration and dosing vary, limiting generalisability. “Autologous” is not an efficacy claim.
Stem-cell / mesenchymal-cell injections
“This has not been shown to regrow cartilage in an arthritic joint. It is expensive and should not be used outside a properly registered clinical trial.”
- The 2024 Australian standard says do not offer adipocyte cell suspensions or mesenchymal stem cells for knee arthritis.
- The TGA states established stem-cell treatment in Australia is for specific blood and immune disorders — not arthritis.
- Unproven cell treatments carry infection, allergic, immunological and abnormal-tissue risks.
- Advertised courses may exceed $5,000 (indicative market figure).
Four things to keep on the record
Hot, red joint or fever
Infection is rare but serious; arrange urgent medical review.
Short-lived flare
Increased pain may settle within 1–2 days.
Diabetes check
Corticosteroid may temporarily raise blood glucose.
Replacement planned?
No corticosteroid in that joint within 3 months of planned arthroplasty.
The 3-month rule
Document the drug, joint and date of every intra-articular injection. Avoid corticosteroid injection into the operative joint within 3 months of total hip or knee arthroplasty.
What it costs here — without promising billing
| Injectable | Cost & access position |
|---|---|
| Corticosteroid | May be bulk billed when Medicare-eligible and referred; confirm when booking. |
| Euflexxa gel injection | Bulk billing is available from some Adelaide providers for eligible Medicare patients; confirm before booking. Jones Radiology referrer sheet (Feb 2024) · Light Radiology Euflexxa information |
| Other gel brands | A private medicine or procedure fee may apply. |
| Platelet-rich plasma | $300–$800 per injection indicative; no Medicare rebate. |
| Stem-cell products | $5,000+ advertised; not recommended outside a registered trial. |
When injections have stopped earning their keep
- Night pain or loss of function despite a well-delivered non-surgical program.
- Each injection gives less relief or a shorter response than the previous one.
- Advanced joint-space loss on a clinically indicated weight-bearing X-ray.
- True mechanical locking, recurrent giving way or diagnostic uncertainty.
- The patient wants a definitive opinion on non-surgical versus surgical options.
- A possible injection is being considered within 3 months of planned arthroplasty.
Referral acknowledged same day · privately referred patients usually seen within 1–2 weeks · correspondence within 48 hours
The patient handout
Joint injections — a plain-English guide for patients
The same four verdicts, written for the person in front of you. Hand it across the desk or send the link.
- Australian Commission on Safety and Quality in Health Care. Osteoarthritis of the Knee Clinical Care Standard — fact sheet for clinicians (2024). safetyandquality.gov.au
- American Academy of Orthopaedic Surgeons. Management of Osteoarthritis of the Knee (Non-Arthroplasty), 3rd ed (2021). aaos.org
- McAlindon TE et al. Intra-articular triamcinolone vs saline: knee cartilage volume and pain. JAMA. 2017;317(19):1967–1975. jamanetwork.com
- Bennell KL et al. Intra-articular PRP vs placebo: RESTORE. JAMA. 2021;326(20):2021–2030. jamanetwork.com
- NICE. Osteoarthritis in over 16s, NG226 (2022) — rationale and impact. nice.org.uk
- Bannuru RR et al. Therapeutic trajectory of hyaluronic acid vs corticosteroids in knee OA. Arthritis Rheum. 2009;61(12):1704–1711. doi.org
- Lai Q et al. Prior intra-articular corticosteroid injection within 3 months and deep-infection risk after arthroplasty. Clin Orthop Relat Res. 2022. pmc.ncbi.nlm.nih.gov
- Therapeutic Goods Administration. Stem cell treatments and regulation — a quick guide for consumers. tga.gov.au
- Adelaide MRI. Bulk-billing policy. adelaidemri.com
- Jones Radiology. Euflexxa referrer information (Feb 2024). jonesradiology.com.au
- Light Radiology. Euflexxa injections. lightradiology.com.au
Ortho Precision™ | © 2026
General clinical information for registered health professionals. It does not replace assessment of the individual patient. Evidence and fees change; reviewed July 2026. Ortho Precision™ and the Ortho Precision mark are trademarks of Ortho Precision. © 2026 Ortho Precision. All rights reserved.
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Dr Yas Edirisinghe MBChB, BHB, MSurg, FRACS, FAOrthA — specialist orthopaedic surgeon (hip & knee), Adelaide. AHPRA reg. MED0001219741. Rooms: 08 7081 4100 · admin@orthoprecision.com.au. Information on this page is for referring clinicians; it is general in nature and does not replace individual clinical assessment. All surgery carries risk, which is discussed at consultation.