PLATELET-RICH PLASMA (PRP)

01 / Understand

What is it?

PRP is prepared from a patient's own blood to produce a platelet-rich fraction. Platelet concentration, white-cell content, processing and treatment schedules vary, so two procedures called PRP may differ materially.

02 / Understand

How is it supposed to work?

Platelets release signaling proteins involved in repair and inflammation. This provides a proposed biological rationale, not proof that injecting PRP rebuilds cartilage or repairs a torn ACL.

03 / Understand

What does the human evidence show?

Knee osteoarthritis has randomized human studies. The AAOS 2021 guideline describes limited-strength evidence for PRP symptom and function benefits, with variation between studies.

In the 2021 RESTORE placebo-controlled trial, PRP did not significantly improve the primary pain outcome or reduce cartilage-volume loss at 12 months. This result concerns the patients and preparation studied, not every PRP product or diagnosis.

04 / Understand

What outcomes matter?

Pain, function, structural healing, mechanical stability, return to sport, reinjury and long-term outcomes are different measures. Feeling better does not necessarily mean a ligament has reattached or that a knee is ready for cutting and pivoting.

Ask how each relevant outcome will be measured, how long follow-up lasts, and what would count as a meaningful improvement for your activity goals.

05 / Understand

Safety, limitations & regulatory context

Using your own blood does not remove injection-related risks. Ask how the preparation is characterized and what benefit is expected for your condition.

Regulatory context depends on the device, product, indication and jurisdiction. A device clearance is not proof of cartilage restoration or approval of every advertised clinical claim.

Evidence, in context.

These assessments apply only to the named condition and outcome. Evidence strength is not a treatment safety score.

Questions to ask your clinician.

1. Which PRP preparation is proposed, and what studies used a comparable preparation?
2. Are we targeting symptoms or structural healing, and how will we measure that?
3. What is my diagnosis, and which outcome are we trying to improve?
4. What alternatives—including rehabilitation or no procedure—are reasonable for me?
5. What complications should I understand, and how will we monitor progress?
6. What criteria would guide a return to sport, and who will assess them?

Research references.

• AAOS clinical practice guideline · 2021Management of Osteoarthritis of the Knee (Non-Arthroplasty)
• Randomized placebo-controlled human trial · 2021Effect 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

Evidence and experience are different.

Read the founder's account of improved knee function, encouraging imaging and persistent instability—without treating an individual experience as proof of efficacy.