Platelet-rich plasma, or regenerative injection therapy, treats common musculoskeletal conditions, including knee arthritis. We produce PRP from whole blood taken from your arm. The blood is spun, separating the heavier red and white cells from the lighter platelets and plasma. This plasma, containing a higher concentration of platelets and growth factors, is injected into the joint. Recent evidence suggests that PRP improves pain and function in knee arthritis. However, usually more than one injection is required. Also, the effects last only 6-12 months and rarely go beyond a year. Recently, a new type of regenerative injection therapy called Nstride claims to give longer-lasting pain relief of up to 3 years with only one injection. Could Nstride be the new regenerative injection therapy?

How is Nstride different from normal PRP? 

N stride

Like normal PRP, Nstride PRP is taken from whole blood and spun in a centrifuge. First, we separate the plasma containing platelets and white cells from the heavier red cells. The plasma is then turned again in a separate unique tube. This second spin super concentrates the growth factors (or good proteins) and removes the ‘bad’ proteins. This dual-spin tips the balance toward a more significant and longer-lasting effect on pain and swelling.

Although Nstride is just one injection, the cost is considerably more than normal PRP. Generally, the cost of one Nstride injection is £2000 compared to a normal PRP of £480. 

How much blood do we need for a Nstride treatment? 

We take about 55 MLS of whole blood. This is so we can concentrate the platelets to 8x normal and white cells to 4x normal. In comparison, normal PRP has concentrates of 2-3x normal.

Are there side effects?

Generally, people tolerate a PRP injection well. However, you may experience a short-term increase in pain and swelling for about two weeks after the injection. We advise people not to exercise if they develop a flare. Other side effects include a slightly increased risk of infection – although the risk is lower than any additional injection.

What are the advantages of Nstride PRP? 

A supposed advantage of Nstride over PRP systems is that the concentration of platelet and white cells is much higher. Given the higher concentration, some practitioners say the effect is so much higher, meaning that only one injection is needed and lasts up to 3 years.

If we only need one injection, this significantly changes from current PRP treatments (which need 2-3 injections). Also, the claims that Nstride provides three years of pain relief are much better than current PRP systems, which offer only 6-12 months of relief.

What is the evidence for Nstride? Is what we read all true?

Unfortunately, the evidence is still a little underwhelming.

A recent higher-level study compared the injection of Nstride PRP with a placebo. So one half of the group received the trustworthy PRP, and another group received sterile water. The doctors and subjects did not know the substance injected, a process called blinding. Surprisingly, there was no difference between the two groups until 12 months. There was a difference in some pain scores but no difference in overall functional scores.

More recently, doctors followed subjects with knee arthritis and had a Nstride injection. At the end of the study, 75% of subjects had pain relief three years after only one injection.

Although three years of pain relief after just one injection is exciting news, we need to see more evidence that N Stride is better and more cost-effective than normal PRP.

So should you consider Nstride PRP? 

Based on what we currently know, we do not suggest you pay extra for Nstride However, a higher concentration of platelets and white cells doesn’t necessarily mean that Nstride is better or lasts longer.

In the meantime, normal PRP is a good option for knee arthritis combined with exercise and other treatments. You can review the evidence for PRP here.

Also, high-molecular weight hyaluronic acid such as Durolane shows a great response with one single injection but without the high price tag.

Platelet-rich plasma injections - alternative to cortisone injection in shoulder

Final word from Sportdoctorlondon about Nstride prp 

To date, the evidence suggests that Nstride PRP is no better than normal PRP for knee arthritis.  Does the evidence justify the extra cost? Probably not until more evidence comes to hand. We look forward to seeing a randomised control trial on the use of Nstride in knee arthritis – which we believe will be published shortly. Stay tuned.

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Dr Masci is a specialist sports doctor in London. 

He specialises in muscle, tendon and joint injuries.