Key facts
- What it is: a concentrated preparation of the patient's own platelets, injected into a joint or soft tissue to support healing and reduce inflammation.
- How it's delivered: under ultrasound or fluoroscopic image guidance, so the injection reaches the exact target rather than relying on surface landmarks.
- Strongest evidence: mild-to-moderate knee osteoarthritis — leukocyte-poor PRP has outperformed hyaluronic acid and corticosteroid injections in several recent meta-analyses.
- Mixed evidence: some tendon conditions show more modest or inconsistent benefit — this is discussed honestly during consultation, not oversold.
Platelet-rich plasma (PRP) therapy uses a concentrated preparation of a patient's own platelets — drawn from a blood sample and processed in a centrifuge — to deliver a high concentration of growth factors directly to an injured or arthritic joint or tendon. Because it's prepared from the patient's own blood, the risk of allergic reaction is minimal.
How image-guided PRP injection works
A blood sample is taken and processed to separate and concentrate the platelet-rich portion of the plasma. This is then injected into the target joint or tissue under real-time image guidance — ultrasound for most soft-tissue and joint targets, or fluoroscopy where deeper or more precise placement is needed. Image guidance means the injection is confirmed to be exactly where it needs to be, rather than relying on anatomical landmarks alone, which matters for both effectiveness and safety.
What PRP is used for
PRP is most established as a treatment for mild-to-moderate knee osteoarthritis, where it's used as an alternative or adjunct to corticosteroid or hyaluronic acid injections. It's also used for select tendon conditions — such as tennis elbow (lateral epicondylitis) and some rotator cuff presentations — though the evidence here is more variable and the benefit less consistent than for knee OA.
What the evidence shows
The evidence for PRP varies meaningfully by condition, which is worth being upfront about rather than treating PRP as a single blanket therapy.
Knee osteoarthritis — strongest evidence: multiple 2025 systematic reviews and meta-analyses, alongside a 2025 AAPM&R consensus guidance statement, support leukocyte-poor PRP as providing superior pain relief and functional improvement compared with hyaluronic acid and corticosteroid injections in patients with mild-to-moderate knee OA (Kellgren-Lawrence grades I–III).
Rotator cuff tendinopathy — moderate, mostly short-term evidence: a 2025 systematic review and meta-analysis of around 2,000 patients found PRP produced significant short-term pain relief and functional improvement in the first three to six months compared with controls.
Achilles tendinopathy — weaker evidence: a 2025 umbrella review of systematic reviews found no statistically or clinically significant difference between PRP and control treatments for chronic Achilles tendinopathy, with any short-term benefit not sustained longer-term.
This is why patient selection and setting realistic expectations matter — PRP for knee osteoarthritis has a genuinely strong and growing evidence base, while PRP for some tendon conditions is better framed as a reasonable option among several, not a guaranteed fix.
Common questions
What conditions is PRP used for?
PRP is most commonly used for mild-to-moderate knee osteoarthritis, and is also used for some tendon conditions such as tennis elbow, though the evidence for tendon indications is more mixed than for knee osteoarthritis.
Does PRP work better than cortisone or hyaluronic acid?
For mild-to-moderate knee osteoarthritis, several recent systematic reviews and meta-analyses suggest leukocyte-poor PRP provides better pain relief and functional improvement than hyaluronic acid or corticosteroid injections. Results vary by condition and PRP preparation, so this isn't universal across every use of PRP.
Is PRP therapy safe?
Yes — because PRP is prepared from the patient's own blood, the risk of allergic reaction or disease transmission is minimal. The main risks are the same as any injection: discomfort, bruising, and a small infection risk.
How is PRP injected under image guidance?
Ultrasound or fluoroscopy is used to confirm the needle tip is placed precisely within the target joint or tissue before the PRP is injected, rather than relying on external landmarks alone.
Next step
Wondering if PRP applies to you?
Ask your GP about a referral, or get in touch directly to discuss suitability.
Get in touch