Stem Cells vs PRP: What Is the Difference and Which Fits You?

Are stem cells and PRP the same thing? No. Platelet-rich plasma (PRP) is a concentrate of platelets made from your own blood in a few minutes; it contains growth factors but no living stem cells. Stem cell therapy uses mesenchymal stem cells, which are living cells that release signaling molecules. Both are injected to ease pain and improve function, the evidence for each is still mixed, and neither is a guaranteed fix for a worn-out joint.

PRP vs stem cells at a glance

	PRP (platelet-rich plasma)	Mesenchymal stem cell therapy
What it is	Your own blood, spun down to concentrate platelets and their growth factors	Living mesenchymal stem cells (MSCs), which act mainly through the signals they release
Living stem cells?	No; platelets are cell fragments	Yes
Preparation	Blood draw and centrifuge, same visit	Cells processed in a laboratory; ask where, and for the lab’s certification
Best-studied use	Knee osteoarthritis and certain chronic tendon problems	Knee osteoarthritis; small, early trials in other joints and tendons
Cost and coverage in the US	Rarely covered by insurance	Not FDA-approved for joint or tendon conditions; paid out of pocket

For the step-by-step of a PRP session, our guide to how a PRP injection works covers it. For the cell side, see what mesenchymal stem cell therapy is and how it is studied.

Does platelet-rich plasma work for knees?

The honest answer is that studies disagree. The American Academy of Orthopaedic Surgeons says PRP appears to be effective for certain chronic tendon injuries and for low- to moderate-grade knee osteoarthritis, while noting that more evidence is needed and that few insurance plans pay for it (AAOS OrthoInfo).

On the other side, the RESTORE trial in JAMA randomized 288 people aged 50 or older with mild to moderate knee osteoarthritis to three PRP injections or three saline injections. After 12 months, pain had dropped by 2.1 points with PRP and 1.8 points with saline, a difference that was not statistically significant, and cartilage volume on MRI did not differ (Bennell, JAMA 2021). A network meta-analysis of 35 trials and 3,104 participants reached a more favorable conclusion, ranking PRP and PRP plus hyaluronic acid as the most effective of the injections compared for pain and function at 3, 6 and 12 months, with no increase in treatment-related side effects (Qiao, 2023).

In practice: some people with early to moderate knee arthritis feel better after PRP, part of that is the same placebo response seen with saline, and PRP has not been shown to rebuild cartilage.

What the evidence says about stem cell injections for the knee

A 2025 Cochrane review pooled 25 randomized trials with 1,341 participants. Compared with placebo injections, stem cell injections may slightly improve pain and function for up to six months: average pain was 1.2 points lower on a 0 to 10 scale. The reviewers rated that evidence as low certainty, noted that the cell source, preparation and dose varied widely, and said the effect on joint structure is still unknown (Whittle, Cochrane 2025).

Head-to-head data are scarce. In one randomized trial of 58 patients, a single injection of PRP and a single injection of microfragmented fat tissue (which contains MSCs among other cells) both produced meaningful improvement at six months, with no difference between them (Baria, 2022). So “stem cells are always stronger than PRP” is not something the current research supports. Our guide to stem cell therapy for knees covers candidacy in more detail.

Why some protocols combine stem cells with PRP

Combining the two is common. The idea is that PRP adds growth factors to the environment the cells are placed in. At our clinic, PRP is part of the anti-aging protocol, together with mesenchymal stem cells and exosomes. To be clear about the evidence: the combination arms in the network meta-analysis above paired PRP with hyaluronic acid, not with stem cells, and there is no high-quality trial showing that adding PRP to MSCs gives better joint results than either alone.

PRP for hip bursitis (lateral hip pain)

Much of what gets called trochanteric bursitis is gluteal tendon irritation. In a double-blind trial of 80 patients with chronic gluteal tendinopathy, 82% of those given one PRP injection reached a clinically meaningful improvement at 12 weeks, compared with 56.7% of those given one corticosteroid injection (Fitzpatrick, 2018). The trial excluded full-thickness tendon tears, and exercise-based rehab remains the foundation. See our hip pain program.

When surgery or another treatment is the better choice

• Advanced, bone-on-bone arthritis with deformity, or a joint that no longer gets you through daily life: a knee or hip replacement usually helps more than any injection.
• A knee that locks, gives way or has a loose fragment: that is a mechanical problem, and injections do not fix mechanics.
• A complete tendon tear that has pulled away from the bone, or a torn ligament causing instability: get a surgical opinion first.
• Pain that comes from the back or a nerve and is felt in the knee or hip: the injection would be aimed at the wrong target.

Where stem cell therapy fits

Stem cell therapy may be worth discussing if you have mild to moderate knee or hip arthritis or a chronic tendon problem, you have given exercise therapy and standard care a fair trial, you want to delay or avoid surgery, and you accept that results vary. It is not a fit if you need a joint replacement now, have an active infection or cancer, or expect a guaranteed result. Stem cell therapy for joint conditions is not FDA-approved, which is one reason US patients travel for it.

Pricing is per dose of cells: a 10-million-cell dose is USD 2,362 and a 25-million-cell dose is USD 3,402, converted from Colombian pesos every Monday. Flights and lodging are separate. See knee pain therapy in Medellín for what a knee protocol involves.

Next step

Send your history and recent X-ray or MRI for a free case review. Dr. Catalina Henao, a medical doctor and surgeon from Universidad CES with ISSCA certification in point-of-care regenerative medicine, reviews it and tells you whether PRP, stem cells, both or neither makes sense, with a written quote before you buy flights. Request your free case review.

Frequently asked questions

Is PRP the same as stem cell therapy?

No. PRP is a platelet concentrate made from your own blood and contains growth factors but no stem cells. Stem cell therapy uses living mesenchymal stem cells. The two are sometimes combined in the same protocol.

Does platelet-rich plasma work for knees?

The evidence is mixed. AAOS says PRP appears effective for low- to moderate-grade knee osteoarthritis and a network meta-analysis of 35 trials ranked it among the better injections, but the RESTORE trial found no significant difference from saline at 12 months.

Are stem cells better than PRP for knee arthritis?

Not proven. In a randomized trial of 58 patients, PRP and microfragmented fat tissue containing stem cells gave similar improvement at six months. Stem cell injections show a small benefit over placebo, with low-certainty evidence.

Why combine stem cells with PRP?

PRP adds growth factors to the area where the cells are placed. Our anti-aging protocol uses mesenchymal stem cells, exosomes and PRP together, but no high-quality trial has shown the combination beats either one alone for joints.

Does PRP help hip bursitis?

For chronic gluteal tendinopathy, the usual cause of lateral hip pain, one randomized trial found more patients improved meaningfully at 12 weeks with PRP (82%) than with a corticosteroid injection (56.7%).

Sources

• AAOS OrthoInfo: Platelet-Rich Plasma (PRP)
• Bennell KL et al. Effect of intra-articular PRP vs placebo injection on pain and medial tibial cartilage volume in knee osteoarthritis: the RESTORE randomized clinical trial. JAMA, 2021
• Qiao X et al. Efficacy and safety of corticosteroids, hyaluronic acid, PRP and combination therapy for knee osteoarthritis: systematic review and network meta-analysis. BMC Musculoskeletal Disorders, 2023
• Whittle SL et al. Stem cell injections for osteoarthritis of the knee. Cochrane Database of Systematic Reviews, 2025
• Baria M et al. Platelet-rich plasma versus microfragmented adipose tissue for knee osteoarthritis: a randomized controlled trial. Orthopaedic Journal of Sports Medicine, 2022
• Fitzpatrick J et al. The effectiveness of PRP injections in gluteal tendinopathy: a randomized, double-blind trial comparing a single PRP injection with a single corticosteroid injection. American Journal of Sports Medicine, 2018