Direct Answer: PRP (Platelet-Rich Plasma) is one of the most extensively studied orthobiologic treatments for knee osteoarthritis, with a growing body of clinical research suggesting it may reduce pain and improve function for some patients, particularly in mild-to-moderate cases. It is not a cure for arthritis, and results vary by patient — a personalized evaluation is the only way to know if it's a reasonable option for your knee.
How PRP Is Thought to Help Knee Osteoarthritis
PRP is prepared from a small sample of a patient's own blood, concentrated to increase platelet content, then injected directly into the knee joint. The theory is that the growth factors and signaling proteins released by concentrated platelets may help modulate inflammation and support the joint's own repair processes — though the exact mechanisms and how consistently they translate into lasting symptom relief are still active areas of research.
What the Evidence Shows
Knee osteoarthritis is the most heavily studied application of PRP in orthopedics. A substantial number of clinical trials have compared PRP to alternatives like hyaluronic acid and corticosteroid injections, with many (though not all) showing meaningful improvements in pain and function, particularly in mild-to-moderate osteoarthritis. As discussed in our earlier piece on why PRP concentration and preparation method matter, study results vary partly because different trials use different PRP systems and concentrations — which makes it difficult to generalize "PRP works" or "PRP doesn't work" without specifying which PRP. Evidence for advanced, bone-on-bone arthritis is considerably weaker than for early-to-moderate disease.
Who May Be a Candidate
Patients with mild-to-moderate knee osteoarthritis who want to explore options before or instead of surgery, who have not had adequate relief from more conservative measures (weight management, physical therapy, activity modification), and who understand PRP is not guaranteed to eliminate symptoms may be reasonable candidates for a consultation.
Who May Not Be a Good Candidate
Patients with severe, bone-on-bone osteoarthritis, significant joint deformity, active infection, certain blood disorders, or those who have not yet tried more conservative measures are generally less likely to be good candidates, and should discuss alternatives with their physician.
When Surgery May Be More Appropriate
For patients with advanced structural damage, significant deformity, or symptoms that have failed to respond to a full range of conservative and orthobiologic options, joint replacement or another surgical approach may offer more predictable relief. This is a decision best made collaboratively, weighing severity, goals, and overall health.
Dr. Tortland's Perspective
I think PRP has a real, evidence-supported role for the right knee osteoarthritis patient — but I'm careful not to oversell it. It is not a substitute for a thorough evaluation, and I don't think every patient with knee arthritis is a good candidate. What I try to do is walk through the evidence honestly, including its limitations, and help each patient understand where they fall on that spectrum before we decide together whether it's worth trying.