Platelet-Rich Plasma (PRP)

What it is

Platelet-rich plasma is made from your own blood. We draw a small volume, spin it in a centrifuge, and separate the layers: red blood cells at the bottom, platelet-poor plasma at the top, and a concentrated platelet layer in between. That middle layer — 4 to 7 times your baseline platelet concentration — is the PRP.

Why does platelet concentration matter? Because platelets are not just clotting agents. They're repositories of growth factors that play a direct role in tissue repair. When we inject a concentrated dose into an injured tendon, joint, or ligament, we're delivering a high-signal biological message that tells the tissue to start healing.

Who it's for

PRP works best when the target tissue is in a state of chronic degeneration rather than acute inflammation. The conditions with the strongest clinical evidence include:

• Chronic tendinopathy — lateral epicondylitis (tennis elbow), Achilles tendinopathy, patellar tendinopathy, proximal hamstring tendinopathy
• Knee osteoarthritis — mild to moderate joint space narrowing where we're managing symptoms and slowing progression
• Partial-thickness rotator cuff tears — partial injuries not responding to conservative care
• Plantar fasciitis — particularly chronic cases that haven't responded to shockwave, orthotics, or physical therapy
• Ligament sprains — grade I and II injuries where accelerating repair is the goal

PRP is not appropriate for acute inflammatory conditions, active infection, or as a first-line treatment when simpler options haven't been tried.

The procedure

The entire appointment takes about 45 minutes. We draw 15 to 30 mL of blood from your arm and centrifuge it in the office. While the sample spins, I prepare the injection site with ultrasound.

Ultrasound guidance is not optional here. Injecting PRP into the wrong tissue plane wastes the treatment. For tendons, I use a fenestration technique — passing the needle through the degenerated area multiple times under ultrasound visualization to distribute the PRP evenly and stimulate a fresh healing response.

We numb the skin at the needle entry point with a small amount of local anesthetic. We do not mix anesthetic with the PRP itself — local anesthetics are cytotoxic to platelets and would undermine the entire treatment.

What to expect afterward

A post-injection flare — increased pain and swelling for 24 to 72 hours — is normal and expected. This is not a complication. It is the inflammatory response we intentionally triggered. Do not fight it with anti-inflammatory medications (NSAIDs like ibuprofen or naproxen). That would suppress the cascade we just initiated.

Ice for comfort. Rest the treated area for a few days. Then begin a gradual loading program — for tendons especially, progressive eccentric loading is what drives the actual remodeling. The injection creates the conditions for healing; the loading program does the work.

Full results take 8 to 12 weeks. PRP is not a quick fix. If you need significant pain relief in days rather than weeks, corticosteroid injection is a better tool for that specific goal.

A note on the evidence

PRP literature is notoriously heterogeneous. Studies use different centrifuge protocols, platelet concentrations, injection volumes, activation techniques, and target tissues — and then report conflicting results. When someone says "the evidence for PRP is mixed," they're often comparing apples to oranges across incompatible preparations.

The best-supported applications are lateral epicondylitis and knee osteoarthritis. For other indications, I discuss the strength of evidence honestly with each patient. Some people are appropriate candidates and some aren't, and the decision should be made together.