What it is
Platelet-rich plasma, or PRP, is a preparation made from a person's own blood. A small blood sample is drawn and spun in a device called a centrifuge, which concentrates platelets in a small amount of plasma. Platelets are blood components involved in the body's normal clotting and healing processes.
In the context of knee arthritis, PRP is sometimes discussed as an injection into the knee joint. Knee arthritis, often osteoarthritis, involves changes to the joint's cartilage and surrounding tissues over time, and it can cause pain, stiffness and swelling.
Regulatory status matters here. In the U.S., the PRP preparation devices are generally cleared by the FDA for preparing the concentrate, but using PRP for knee arthritis is generally considered an off-label or investigational use rather than an FDA-approved treatment for that condition. Evidence is still developing and is described as limited or mixed. PRP is also different from stem cell products. The only FDA-approved stem-cell products in the U.S. are cord-blood-derived hematopoietic progenitor cell (HPC) products for certain blood and immune disorders, used in specialist transplant settings. The FDA has warned the public about unapproved stem cell and exosome products, and no exosome product is FDA-approved.
How it’s traditionally been approached
Knee arthritis has traditionally been approached with a range of conventional options. These often include activity modification, weight management, physical therapy, strengthening and stretching, and supportive devices such as braces or canes.
Clinicians may also discuss over-the-counter or prescription medications, and injections of other kinds, as part of a wider conversation. When symptoms are significant, some people talk with an orthopedic surgeon about surgical options, including joint replacement.
PRP and other orthobiologic approaches have been added to these conversations by some clinicians in recent years. Whether any option is appropriate depends on the person, and only a licensed clinician can decide that after an evaluation. Holistic or alternative framing of a product never changes its FDA status.
How the right provider may help
The right provider, such as a sports medicine, orthopedic or regenerative medicine clinician, may help you make sense of your knee symptoms. A visit generally begins with a conversation about your history, daily activities and goals, followed by a physical exam and, often, a review of imaging.
A good provider may explain the range of options, including conventional care, and be candid about what is known and unknown regarding PRP. They may describe the possible risks, the limits of the evidence, and the alternatives, rather than promising any result.
Helpful questions to ask: Is this use FDA-approved or off-label? Is any study registered on ClinicalTrials.gov with IRB oversight? Is my license check with the state medical board confirmed? Will I receive written informed consent covering risks and alternatives? What are my other options, including not treating? Be cautious of cure-all or 'treats everything' claims, paying to join a 'clinical trial', testimonials in place of evidence, and pressure to travel abroad or across states for treatment.
The whole-person view
Living with a painful knee can affect more than movement. Body, mind and stress influence each other, so ongoing pain may affect sleep, mood and motivation, and stress or worry can in turn change how pain is felt. Looking at the whole person, including movement, rest, relationships and daily stress, is a reasonable part of any care conversation.
Some people find body-based support helpful, such as the approaches offered through Somatic Experiences. Others value talking with a licensed professional about coping with chronic pain and uncertainty, such as through Therapists.plus. These are complementary ways of supporting wellbeing and do not replace a medical evaluation.
Somatic Experiences: embodiment and movement →Somatic Experiences: nervous system regulation →Therapists.plus: mind body connection →
Keep in mind
- PRP for knee arthritis is generally not FDA-approved for that use, and evidence is limited or still developing, so ask any provider about regulatory status.
- Only a licensed clinician can decide what is appropriate for you after an evaluation, and licensed professionals should guide care for serious conditions.
- Verify the clinician's license with your state medical board, confirm any study on ClinicalTrials.gov, and get written informed consent covering risks and alternatives.
- For emergencies call 911; in a crisis call or text 988. This page is educational only and is not medical advice.
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Frequently asked questions
What is PRP for knee arthritis?
PRP for knee arthritis is an injection of platelet-rich plasma, made from your own blood, into the knee joint. It is used by some clinicians in discussions of osteoarthritis care, but it is generally an off-label or investigational use. A licensed clinician can explain whether it fits your situation.
Is PRP for knee arthritis FDA-approved?
No, PRP is generally not FDA-approved as a treatment for knee arthritis. The devices used to prepare PRP may be FDA-cleared for preparing the concentrate, but that is different from approval for treating a condition. Ask your provider to explain the regulatory status in plain terms.
Does PRP work for knee arthritis?
The evidence is limited and mixed, and no outcome can be promised. Researchers continue to study it, and results may vary between people and preparations. A licensed clinician can describe what is and is not known.
Is PRP the same as stem cell therapy?
No, PRP is not stem cell therapy. PRP concentrates platelets from your blood, while stem cell products involve different types of cells. In the U.S., the only FDA-approved stem-cell products are cord-blood-derived hematopoietic progenitor cell products for certain blood and immune disorders, and the FDA has warned about unapproved stem cell and exosome products.
What should I ask before considering PRP for my knee?
Start by asking about the product's FDA status, the provider's license, and the risks and alternatives. Ask whether any study is registered on ClinicalTrials.gov with IRB oversight, and request written informed consent. Be wary of cure-all claims, paying to join a 'clinical trial', and pressure to travel for treatment.
Who provides PRP for knee arthritis?
PRP for knee arthritis is offered by some sports medicine, orthopedic and regenerative medicine clinicians. Providers.plus lists licensed providers you can explore. Always confirm credentials with your state medical board and have an evaluation first.
Educational resource. StemCell.biz shares general information and connects people with independent providers. It is not medical advice, diagnosis or treatment. Talk with a licensed professional about your health.