Platelet-rich plasma (PRP) is prepared from a person’s blood and studied for several musculoskeletal conditions. The term regenerative does not prove that an injection regrows cartilage or repairs a damaged joint. Benefit depends on the condition and preparation, and research and guideline recommendations remain mixed. The evidence should be discussed for the specific condition being treated. [1] [2] [3] [4]
What is PRP?
Blood is collected and processed to produce a preparation with a higher concentration of platelets. Platelets contain proteins involved in healing, which provides a biological rationale for research. A plausible mechanism is different from demonstrated improvement in pain, function or joint structure in patients. Preparations and injection protocols vary. [1]
What does the evidence show for knee osteoarthritis?
Guidelines disagree. The American Academy of Orthopaedic Surgeons states that PRP may help symptoms in knee osteoarthritis, but rates the supporting recommendation as limited. The American College of Rheumatology’s 2026 guideline summary strongly recommends against PRP for knee and hip osteoarthritis. [2] [3]
NICE identifies limitations in the quality of evidence and recommends additional arrangements for consent, monitoring and audit or research. In the RESTORE trial, 288 people with mild-to-moderate knee osteoarthritis received PRP or saline injections. At one year, the trial did not find a significant difference in pain or cartilage-volume outcomes. That is a reason to avoid claims of proven cartilage regeneration. [4] [5]
Can results be applied to other conditions?
Evidence for one joint, tendon or preparation should not be assumed to apply to another. Before considering an injection, ask for studies that match the actual diagnosis, body area, product and intended outcome. Terms such as biological or natural do not answer these questions.
Ask whether the treatment being discussed is the same preparation used in the cited studies. A broad treatment category does not establish the expected benefit for a specific person.
What established options should be discussed?
For knee or hip osteoarthritis, exercise, appropriate weight management and other individualised treatments remain important. The 2026 ACR guidance supports these foundations and recommends tailoring medicines and other care to symptoms, health conditions and treatment risks. [3]
Ask whether rehabilitation has been sufficiently tailored and supported, whether the diagnosis is secure and whether another opinion would change the plan. When symptoms remain substantial, compare all reasonable options rather than choosing an injection because its name suggests tissue repair.
Risks, costs and expectations
Using your own blood does not make an injection risk free. Pain can increase after treatment, and infection, tissue injury or nerve injury are possible. Benefit is not assured. Ask about preparation, number of injections, expected recovery and how adverse effects will be handled. [1]
Request a written estimate covering the proposed course and follow-up. Confirm any insurance arrangements directly rather than assuming coverage. Decide in advance what result would justify further treatment and when to stop if that result is not achieved.
Questions patients often ask
Can PRP regrow my knee cartilage?
It should not be offered with that promise. The RESTORE trial did not show a significant cartilage-volume benefit over saline at one year. [5]
Why do doctors give different advice?
Studies vary in patient selection and preparation, and guideline panels interpret uncertain findings differently. Ask which evidence supports the recommendation for your case. [2] [3] [4]
Does PRP replace physiotherapy?
It should not be treated as a substitute for an appropriate rehabilitation plan. Ask how the proposed intervention fits with the other care needed to improve function. [3]
What would make the decision clearer?
Ask: What is the diagnosis? What benefit matters to me? How likely is no benefit? What are the alternatives? What will the full course cost? A clear answer to those questions is more useful than a broad success claim.
Related information
Evidence and further reading
- Platelet-rich plasma (PRP). American Academy of Orthopaedic Surgeons, OrthoInfo; Accessed 10 November 2026.
- Management of osteoarthritis of the knee (non-arthroplasty), third edition. American Academy of Orthopaedic Surgeons; 31 August 2021.
- 2026 update of recommendations for management of osteoarthritis of the knee, hip and hand — guideline summary. American College of Rheumatology; Posted 14 September 2026; approved 8 September 2026.
- Platelet-rich plasma injections for knee osteoarthritis: evidence statement. NICE, formerly IPG637; January 2019.
- Effect of intra-articular PRP vs placebo injection on pain and medial tibial cartilage volume: the RESTORE randomised clinical trial. JAMA; 23 November 2021.
Evidence sources checked: 10 November 2026.
This information supports discussion with a healthcare professional and does not replace an individual assessment.