Platelet-rich plasma (PRP), also known as regenerative injection therapy, is used to treat common musculoskeletal conditions, including knee arthritis. We make PRP from whole blood taken from your arm, spin it to concentrate the platelets and growth factors, and inject it into the joint. Evidence suggests PRP may improve pain and function in knee arthritis — though it usually needs more than one injection, and the effect typically lasts 6–12 months. nStride is a newer, more concentrated variant that claims to give longer-lasting relief — up to three years — from a single injection. It’s an appealing promise. But based on the current evidence, we don’t offer nStride at Sport Doctor London because it’s far more expensive than standard PRP and there’s no good evidence it works better. This page explains why, and what we recommend instead.

What is nStride, and how does it differ from standard PRP?

N stride

nStride (an “autologous protein solution”, or APS) starts like normal PRP — whole blood, spun in a centrifuge to separate the plasma and platelets from the heavier red cells. nStride then adds a second spin, which super-concentrates the growth factors and anti-inflammatory proteins. This dual-spin is meant to tip the balance towards a bigger, longer-lasting effect on pain and swelling.

From about 55 ml of blood, nStride concentrates the platelets to around 8 times normal and the white cells to around 4 times normal, compared with 2–3 times for standard PRP.

The catch is the price: one nStride injection costs around £2,000, compared with about £500 for a standard PRP injection. 

What are the claimed advantages of nStride?

The pitch rests on that higher concentration. Because nStride concentrates platelets and white cells so much, some practitioners claim the effect is stronger, so you need only one injection, and it lasts up to three years. If true, that would be a real step up from standard PRP, which typically needs a course of injections and gives 6–12 months of relief.

The question is whether the evidence supports those claims.

What is the evidence for nStride?

Unfortunately, the evidence is underwhelming.

A higher-quality blinded study compared nStride against a placebo — half the patients received nStride, half received sterile water, with neither the doctors nor the patients knowing which group received which. There was no difference between the groups until 12 months; even then, only some pain scores differed, with no difference in overall function.

A separate follow-up study reported that 75% of patients still had pain relief three years after a single injection, which sounds impressive. Still, it wasn’t a controlled comparison, so we can’t be sure the injection was responsible.

So while three years of relief from one injection is an exciting claim, we need stronger evidence that nStride genuinely beats standard PRP — and justifies four times the cost — before recommending it.

So, should you pay extra for nStride? Is nStride worth it? 

Based on what we currently know, we don’t recommend paying extra for nStride. A higher concentration of platelets and white cells doesn’t automatically mean better or longer-lasting results, and the best available trial didn’t show a convincing functional advantage over placebo.

What we recommend instead of nStride

There are well-evidenced, more cost-effective options we do offer:

  • Standard PRP — a viable, evidence-backed option for knee arthritis, used alongside exercise, at a fraction of the cost of nStride.
  • Arthrex ACP Max — our preferred second-generation, one-shot PRP. It uses a dual-syringe system to deliver a high platelet dose (around 5–12 billion platelets) in a single injection, and it’s available in Dr Masci’s clinic.

If you’re weighing up regenerative injections for knee arthritis, these are the options we’d discuss first.

Frequently asked questions about nStride

Is nStride better than standard PRP? Is nStride worth it? 

The current evidence doesn’t show a convincing advantage. The best blinded trial found no functional difference over placebo until 12 months, so despite the higher concentration and price, there’s no good evidence that nStride outperforms standard PRP for knee arthritis.

Does nStride really last three years?

One uncontrolled follow-up reported relief at three years in 75% of patients, but without a comparison group, we can’t be sure the injection caused it. The three-year claim isn’t yet supported by high-quality controlled evidence.

How much does nStride cost?

Around £2,000 per injection — roughly four times the cost of a standard PRP injection (about £500). The lack of a clear added benefit is the main reason we don’t currently recommend it.

Is nStride the same as PRP?

Not exactly. nStride is an autologous protein solution (APS) — it starts as PRP but adds a second spin to super-concentrate the anti-inflammatory proteins. So it’s a more concentrated variant rather than standard PRP.

What does Dr Masci offer instead of nStride?

Standard PRP, and his preferred one-shot PRP option, Arthrex ACP Max, plus hyaluronic acid options such as Durolane. These are well-evidenced and more cost-effective than nStride.

Would you ever offer nStride in future?

Possibly — if a well-designed randomised controlled trial shows it genuinely outperforms standard PRP and justifies the cost. We keep our injection options under review as the evidence develops.

Final word from Sport Doctor London about nStride PRP: Is nStride PRP worth it? 

To date, the evidence suggests that nStride is no more effective than standard PRP for knee arthritis and costs considerably more. Does that justify the extra expense? Based on what we currently know, no. For now, Dr Masci recommends standard PRP or his preferred one-shot option, Arthrex ACP Max, alongside exercise and other proven treatments.

To discuss the right injection for your knee arthritis, contact the team here or call +44 (0) 203 488 0350.

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