Does PRP Actually Work?

Why this article exists

PRP is marketed aggressively, priced highly, and rarely covered by insurance. That combination should make anyone skeptical, and it is a fair question to ask whether it is worth it.

I offer PRP. I also think it is oversold. Both of those can be true, and you deserve a straight answer about which situations fall into which category.

What PRP is

Platelet-rich plasma is made from your own blood. We draw a sample, spin it in a centrifuge to concentrate the platelets, and inject that concentrate into the injured tissue under ultrasound guidance.

The rationale is that platelets carry growth factors — the signaling molecules involved in tissue repair. Concentrating them at a site that has failed to heal is intended to restart a stalled repair process.

The biological rationale is sound. That is not the same as proof that it works for a given condition, and the gap between mechanism and outcome is where a lot of medicine goes wrong.

The problem with reading the PRP literature

"PRP" does not describe one thing. Preparations vary enormously between studies and between clinics:

Leukocyte-rich versus leukocyte-poor. Whether white blood cells are included changes the inflammatory profile substantially, and the two appear to behave differently — leukocyte-poor is generally favored for intra-articular joint injection, leukocyte-rich possibly better for tendon.

Platelet concentration. Varies several-fold across systems. Some commercial kits produce concentrations barely above baseline blood.

Activation, volume, injection technique, number of sessions, and whether ultrasound guidance was used all differ.

The result is a literature comparing things that share a name but not a composition. When a meta-analysis pools these, the averaging can obscure real effects and manufacture apparent ones. Read any confident claim about PRP with that in mind.

Where the evidence is reasonably supportive

Knee osteoarthritis. This is the strongest indication. Multiple randomized trials and meta-analyses suggest PRP outperforms hyaluronic acid and saline for pain and function, with benefit that can persist six to twelve months. The effect is meaningful but not dramatic, and it works best in mild to moderate arthritis. In a bone-on-bone knee, expectations should be low.

Lateral epicondylitis (tennis elbow). Reasonable evidence, particularly compared against corticosteroid injection at longer follow-up, where PRP tends to do better past three months while cortisone does better early and then loses ground.

Chronic tendinopathy with structural change on ultrasound. Where I see the best responses in practice is a tendon with visible degeneration or partial tearing that has genuinely failed a proper loading program.

Where the evidence is weak or negative

Achilles tendinopathy. Several well-conducted randomized trials found no benefit over placebo injection, including at long-term follow-up. This is one where I am straightforward with patients: the evidence does not support it, and the money is better spent elsewhere.

Rotator cuff tears. Inconsistent. Some signal for augmenting surgical repair, much less for injecting a full-thickness tear and expecting it to heal.

Plantar fasciitis. Mixed. Some trials favor PRP over corticosteroid at longer follow-up, others show no difference. Shockwave has a more consistent record here and costs less.

Advanced arthritis of any joint. PRP does not regrow cartilage. Any clinic implying otherwise is describing something that has not been demonstrated in humans.

Spine and disc conditions. Early and unproven. Be cautious with anyone offering intradiscal PRP as an established treatment.

The honest summary

PRP is a reasonable option for specific conditions, in specific tissue states, after appropriate conservative care has been tried properly. It is not a regenerative cure, it does not reverse structural disease, and it is not the right first move for most people.

If you have been offered PRP for a problem you have not yet attempted a real loading program for, the loading program is the better investment. If you have been offered a package of six injections up front, be skeptical.

What it actually involves

A blood draw, roughly 30 to 60 minutes total. The injection itself is often more uncomfortable than a cortisone shot, and a flare of increased pain for several days afterward is normal and expected — it is an inflammatory treatment by design.

You avoid anti-inflammatories around the procedure, since blunting the inflammatory response works against the mechanism. Improvement is gradual over weeks to a few months, not immediate. Many protocols involve one to three injections spaced a few weeks apart.

Because it is your own blood, allergic reaction and rejection are not concerns. Infection risk is very low with sterile technique.

What I will tell you in the room

I will tell you whether your specific condition is one where the evidence supports this, what response I would realistically expect, what it costs before you commit, and what the alternatives are — including doing nothing, and including the less glamorous option of a properly structured strengthening program.

If PRP is not a good bet for your problem, I will say so. There are enough places willing to sell it to you regardless.