Knee Injections for Arthritis: Comparing Your Options in London

Arthritis occurs when the cartilage in a joint wears away, exposing the bones beneath. This leads to pain, swelling, and reduced function. Simple treatments — exercise, weight loss, and medication — work best and come first. When there are not enough knee injections for arthritis, offer the next step. Dr Masci performs every type of knee injection at his London clinics, all under ultrasound guidance, all as one-stop appointments. This guide compares the five main options — cortisone, hyaluronic acid, Durolane, Arthrex ACP Max PRP, and Arthrosamid — so you can understand which knee shot suits your knee, your goals, and your budget.

Knee injections for arthritis compared at a glance 

Cortisone injections for knee arthritis 

Cortisone is the most commonly used injection for the knee. It is a potent anti-inflammatory that quickly reduces inflammation, swelling, and pain.

Studies show short-term improvement in knee pain after cortisone. The effect is better in milder knee arthritis and lasts up to 3 months. However, cortisone shows no difference from placebo at six months.

Cortisone also carries real concerns. A recent study found a twice-as-high rate of cartilage damage after cortisone injections compared with other injections. Repeated cortisone may bring a knee replacement forward. And if you plan to have a knee replacement, avoid cortisone for at least 3 months before surgery.

Our view: use cortisone for a hot, swollen, acutely painful knee — and use it sparingly. For longer-term control, the options below work better.

Gel injections (hyaluronic acid) for knee arthritis

Hyaluronic acid occurs naturally in joints. Injecting it into the knee lubricates the joint and reduces inflammation. Studies show a moderate effect on arthritis pain lasting 6–12 months.

Product choice matters. High-molecular-weight, cross-linked hyaluronic acid works significantly better — one analysis found it outperformed most other injections and medications for knee arthritis. Durolane meets these criteria, needs only one injection, and is our preferred first long-term option at £490. A single Durolane injection lasts over 400 days on average, and repeat injections stay effective.

PRP injections for knee arthritis

Platelet-rich plasma (PRP) comes from your own blood. We spin the blood in a centrifuge to concentrate the platelets, which carry growth factors, and inject the plasma into the knee. Twenty-three randomised trials show a positive effect of PRP on knee arthritis, and head-to-head studies suggest PRP slightly outperforms hyaluronic acid at 6 and 12 months.

The catch with standard PRP is that it requires up to three injections. The solution is Arthrex ACP Max, a second-generation system delivering 5–12 billion platelets — a far higher dose — in a single injection. Dr Masci offers ACP Max for £1,350, which often undercuts the total cost of a standard multi-injection PRP course.

Arthrosamid injection for knee arthritis

Arthrosamid is a non-degradable polyacrylamide hydrogel — not a hyaluronic acid. The body cannot break it down. The gel integrates into the joint lining, reducing inflammation and providing lasting lubrication.

The results stand out. Recent studies show pain improvement lasting at least 5 years from one injection. In trial data, 73% of patients responded overall, rising to 80–95% in patients under 70. Arthrosamid suits patients with stubborn arthritis who have failed other injections — and patients determined to avoid or delay a knee replacement. Dr Masci offers Arthrosamid at £2,500, significantly less than most other UK centres.

Stem cell injections for knee arthritis

Stem cell therapy attracts attention and big fees. The evidence does not support either. High-level studies show no difference between stem cells and sterile water, and a recent trial found no difference between stem cells and cortisone at one year. Stem cells also do not rebuild cartilage, whatever the marketing says.

Our advice: don’t spend up to £7,000 on stem cells until better evidence arrives. Every option above has stronger data at a lower price.

Which knee injection should you choose?

Our approach follows a simple ladder:

• Acute, hot, swollen knee → cortisone settles it fast. Use sparingly.

• First long-term injection → Durolane (£490). One injection, 12+ months of relief for most, 65–70% effectiveness.

• Durolane failed or wore off — or you want the regenerative option → ACP Max PRP (£1,350). One high-dose injection, 65–70% effectiveness.

• Stubborn arthritis, other injections failed, or you want to avoid surgery → Arthrosamid (£2,500). 75–90% effectiveness, lasts 5+ years.

Combinations also work: hyaluronic acid plus PRP beats PRP alone in recent studies. Dr Masci examines your knee, scans it with ultrasound, reviews your X-rays, and recommends the right rung of the ladder at a single consultation — he will also tell you honestly if an injection is not your best option.

Why have your knee injection with Dr Masci?

Accuracy decides outcomes. Ultrasound-guided knee injections are far more accurate than blind injections, and ultrasound-guided hyaluronic acid produces measurably better results — including fewer subsequent knee replacements. Dr Masci performs over a thousand ultrasound-guided injections every year and teaches injection techniques to doctors across the UK and Europe. Every appointment is one-stop: consultation, diagnostic ultrasound, and injection in a single visit at his London clinics. Read about his injection expertise here.

Frequently asked questions about knee shots for arthritis

What is the best injection for knee arthritis?

It depends on your knee and your goals. For severe acute pain and swelling, cortisone works fastest. For lasting control, the published effectiveness rates are: Durolane 65–70%, PRP 65–70%, and Arthrosamid 75–90% (rising to 80–95% in patients under 70). Arthrosamid is the most expensive; Durolane offers the best value as a first option.

How much do knee injections for arthritis cost in London?

At Dr Masci’s Chelsea clinic: Durolane £490, Arthrex ACP Max PRP £1,350, and Arthrosamid £2,500 — each as a one-stop appointment including consultation and ultrasound. Other clinic locations cost more. Full fees here.

Do knee injections work for bone-on-bone arthritis?

Yes, but all injectables work better in milder arthritis. In bone-on-bone knees, response rates drop. Arthrosamid retains the best results in more advanced disease, and even patients awaiting knee replacement can gain relief.

Should knee injections be done with ultrasound?

Always. Ultrasound-guided injections are far more precise than blind injections. For gel injections in particular, fluid injected outside the joint can cause severe reactions.

Can knee injections rebuild cartilage?

No. No injection — including stem cells — regenerates cartilage. Injections treat pain and inflammation, and they do this well. Beware of any clinic claiming otherwise.

How soon before a knee replacement must I stop injections?

For cortisone, most surgeons require a gap of at least 3 months before surgery — some prefer 6. Tell your surgeon about any recent injections. Arthrosamid does not prevent the need for future knee replacement: studies of knees replaced after Arthrosamid report no problems during or after surgery.

Final word from Sport Doctor London about knee injections for arthritis in London

We use knee injections when exercise, weight loss, and medication are not enough. Use cortisone sparingly for a sore, swollen knee. For lasting relief, follow the ladder: Durolane first, then ACP Max PRP or Arthrosamid for stubborn knees. Always insist on ultrasound guidance, and choose a doctor with genuine injection expertise.

To book a one-stop knee injection in London, contact Dr Masci’s team here or call +44 (0) 203 488 0350.

Related pages on knee injections for arthritis in London:

• Durolane injection for knee arthritis — £490
• Arthrex ACP Max: one-shot high-dose PRP — £1,350
• Arthrosamid injection for knee arthritis — £2,500
• Hyaluronic acid injections: an expert guide
• Combined hyaluronic acid and PRP injection
• Cortisone shot London: a low-cost injection service
• PRP recovery time: what to do before and after PRP
• Fees for ultrasound-guided injections