Knee Injection Comparison
Arthrosamid® vs
Steroid Injection
Corticosteroid injections have a short-term anti-inflammatory role; Arthrosamid® is a non-absorbable hydrogel intended for adult knee osteoarthritis symptom management. Here is the honest comparison, including when either may be inappropriate.
Reviewed byProfessor Paul YF Lee MBBch, FRCS (Tr & Orth), PhDCartilage and joint preservation expertiseQuick Answer
Corticosteroid injections reduce inflammation and generally have a short-term role, with response and duration varying. Arthrosamid® is a non-resorbable hydrogel with published observational group outcomes reported through 24 months. Steroid injections remain useful for selected short-term aims; Arthrosamid is not proved to delay surgery and neither option guarantees a response or duration.
The Headline Difference
Arthrosamid® vs Steroid Injection — the key difference
The core difference is mechanism and intended role. Steroid injections work pharmacologically to reduce inflammation and are generally used for selected short-term aims. Arthrosamid® is a non-absorbable material intended for symptomatic adult knee osteoarthritis. Neither mechanism supplies an individual response or duration guarantee.
Mechanism of Action
How each treatment works
Arthrosamid® is a polyacrylamide hydrogel injected into the knee joint under ultrasound guidance. The gel integrates into the synovial membrane and is intended to remain in the joint. It is not regenerative.
Mechanism is mechanical — physical cushioning and lubrication.
Corticosteroid injections deliver a potent anti-inflammatory (typically methylprednisolone or triamcinolone) directly into the joint. The injection rapidly damps the inflammatory response and the symptoms it produces — pain, swelling and stiffness.
The drug is gradually metabolised over weeks to months, after which the effect tapers off.
How Long Results May Last
Duration and number of injections
Observed to 24 months
Weeks to months
Repeated steroid injections in the same joint require consideration of cumulative concerns, including cartilage and tendon health. That does not make Arthrosamid automatically better.
Treatment Course
Number of injections
One injection is the standard treatment course in suitable patients. Most cases are treated with a single box per joint, delivered as an outpatient appointment.
A steroid injection can sometimes be repeated, but frequency is decided individually after reviewing diagnosis, previous response, medical history and cumulative risks.
Safety and Infection
Safety considerations
Both treatments are delivered under ultrasound guidance at London Cartilage Clinic. The most serious shared risk includes joint infection. Beyond infection, each treatment has its own risk profile. Ultrasound guidance and sterile technique do not eliminate risk.
Corticosteroid injections carry small risks of post-injection flare in the days after the injection, fat-pad atrophy at the injection site, transient blood-sugar rise (relevant for diabetic patients), and concerns about cumulative cartilage and tendon effects from repeated use in the same joint.
Arthrosamid® is non-absorbable and intended to remain in the joint, so a serious infection may be harder to manage than for steroid. This is why we use routine IV antibiotic cover for Arthrosamid® specifically. See Arthrosamid® infection risk and prevention and Arthrosamid® side effects and safety.
Patient Selection
Who each treatment may suit
Steroid injections suit patients with short-term flares of knee osteoarthritis, those who need symptom relief ahead of a specific event (a planned holiday, a wedding, a return to activity), and those for whom a longer-acting injection is not appropriate.
Arthrosamid® may be discussed with patients who have established knee osteoarthritis and are willing to consider a non-absorbable single-injection option, while understanding it is not proved to delay surgery. Neither treatment is a substitute for knee replacement where replacement is clinically appropriate. See who is suitable for Arthrosamid?.
Cost and Value
What each treatment costs
At London Cartilage Clinic, Arthrosamid® costs from £3,000 for one box, inclusive of consultation, ultrasound, the product, the fifteen-step injection protocol and the six-week follow-up. See the Arthrosamid® cost guide for full pricing.
Steroid injections generally have a lower price per dose. Compare the actual recommended treatment, inclusions, expected role and cumulative clinical concerns rather than assuming repeat timing or a particular Arthrosamid duration.
Our Honest Take
When we may recommend each
You have established knee osteoarthritis with mild-to-moderate cartilage wear.
You want to discuss a non-absorbable single-injection option rather than assuming a repeat steroid schedule.
You understand that symptom management is not proved to delay surgery and accept the product-specific safety protocol.
Short-term flare control for symptomatic knee osteoarthritis.
Symptom relief ahead of a specific event (a planned trip, a procedure, return to a specific activity).
As a diagnostic tool, where the response to a single steroid injection helps clarify the source of pain before committing to a longer-acting option.
When Each Is The Wrong Answer
When we would not recommend each
End-stage bone-on-bone arthritis where Arthrosamid® is unlikely to deliver meaningful benefit.
Active infection or unwillingness to accept the conservative safety protocol.
Unrealistic expectation of cure, regeneration or guaranteed permanent relief.
Patients already repeating steroid need a review of diagnosis, benefit and cumulative risk; this does not automatically make Arthrosamid the better answer.
Poorly controlled diabetes, where the blood-sugar effect is a meaningful concern.
Where prior steroid injections have not delivered useful benefit, repeating is unlikely to be the right next step.
The Bottom Line
In summary
Steroid injection and Arthrosamid® are tools for different jobs. Steroid is for selected short-term aims; Arthrosamid® is a non-absorbable single-injection option. Where a patient is on a pattern of repeating steroid, the diagnosis, prior response, cumulative steroid concerns and Arthrosamid evidence limits all need review. Neither is automatically better. The choice is made at consultation with imaging review.
Arthrosamid® vs Steroid Injection
Frequently asked questions
Is Arthrosamid® better than a cortisone injection?
Not automatically. Arthrosamid has observational outcomes reported through 24 months; steroid has a different, often shorter-term role. Evidence, risks, previous response and the clinical aim decide which is appropriate. They are tools for different jobs.
Can I have Arthrosamid® after a steroid injection?
Prior steroid is not automatically a contraindication, but the interval and suitability depend on the diagnosis, injection date, response, current symptoms and infection risk. Timing is agreed at consultation rather than using a universal rule.
How many steroid injections can I have in the same knee?
There is no safe universal number for this page to prescribe. Frequency should be agreed with the treating clinician after considering the diagnosis, previous response, timing, diabetes and cumulative cartilage and tendon concerns.
Is steroid safer than Arthrosamid®?
The treatments have different risk profiles. Steroid carries corticosteroid-specific risks (post-injection flare, fat-pad atrophy, blood-sugar rise, cumulative concerns with repeated use). Arthrosamid® is non-absorbable and intended to remain in the joint, so infection management is more complex if it does occur — which is why we use routine IV antibiotic cover for Arthrosamid® specifically.
Are steroid injections available on the NHS?
Steroid injections may be available through NHS pathways where clinically appropriate; local access varies. Arthrosamid® is not routinely funded by the NHS. See the Arthrosamid® funding and insurance page for detail.
Book an Arthrosamid® Assessment – London
Long-lasting relief starts with the right decision — not just an injection.