PRP Treatment – Platelet Injections for Osteoarthritis and Tendinopathy

PRP stands for Platelet Rich Plasma. It's a treatment that uses your body's own platelets and growth factors, drawn from a small blood sample, to try to stimulate healing in damaged or worn tissue.

How is PRP made?

The treatment starts with an ordinary blood draw, similar to any other blood test you might have at your GP's office. The blood is then spun in a centrifuge, which separates it into layers by weight. The layer with a high concentration of platelets and growth factors is drawn off, and this is the PRP.

Platelets are known for their role in wound healing and regulating inflammation. The idea behind PRP is to concentrate these growth factors and place them exactly where they're needed, to support the body's own healing processes.

How is the injection given?

PRP is injected under direct ultrasound guidance. This means the needle is tracked on the screen the whole time, so the substance can be placed precisely in the relevant tissue – whether that's a tendon, a joint space, or another target area. This makes the treatment more precise than an injection given "blind".

What conditions is PRP used for?

• Knee osteoarthritis, as an alternative or supplement to hyaluronic acid
• Tendinopathies that haven't improved with other treatment, such as jumper's knee or tennis elbow
• Certain partial tendon injuries

The treatment is usually used after more basic treatment – such as targeted exercise and load management – has been tried without sufficient effect.

What does the research say?

Research on PRP is still evolving, and results vary somewhat between studies and conditions – partly because there are different ways of preparing PRP. The evidence is currently strongest for knee osteoarthritis and certain tendon conditions, while the effect for other conditions is less certain. PRP is considered a safe treatment, since it uses the patient's own blood, but it's important to have realistic expectations and discuss whether the treatment is suitable for your specific case.

What can you expect afterwards?

Some increased tenderness in the area for the first few days after treatment is common, since PRP actually triggers a mild local inflammatory response as part of its mechanism of action. The effect usually builds gradually over weeks, not immediately, and treatment is often combined with tailored exercise afterwards for the best result.

Sources

1. Mishra AK, Skrepnik NV, Edwards SG, et al. "Efficacy of platelet-rich plasma for chronic tennis elbow: a double-blind, prospective, multicenter, randomized controlled trial of 230 patients." Am J Sports Med 2014;42(2):463–471.
2. Bennell KL, Paterson KL, Metcalf BR, et al. "Effect of Intra-articular Platelet-Rich Plasma vs Placebo Injection on Pain and Medial Tibial Cartilage Volume in Patients With Knee Osteoarthritis: The RESTORE Randomized Clinical Trial." JAMA 2021;326(20):2021–2030.