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Regenerative Medicine · Autologous Orthobiologic

Platelet-Rich Plasma (PRP)

PRP uses a concentrated portion of your own blood as an orthopedic treatment for selected joints, tendons and ligaments. The important question is not simply whether something is called “PRP” — it is what formulation and platelet dose were prepared, for what diagnosis, and where it was placed.

Am I a Candidate? → Call (808) 439-6201

Not a cure; usually not covered by insurance. Evidence varies by diagnosis and PRP formulation. Not everyone is a candidate.

Common orthopedic uses

  • Knee osteoarthritis
  • Tendon injuries
  • Selected ligament, joint and sports injuries

How It Works

Your own blood, processed for a specific target

01

Blood draw

Blood is drawn from your arm. The starting volume and your baseline platelet count influence the final product.

02

Separate & concentrate

Centrifugation separates blood components and creates a platelet-rich fraction. Different systems can produce very different platelet and white-cell concentrations.

03

Image-guided placement

The prepared PRP is placed at the intended joint or soft-tissue target with ultrasound guidance when appropriate.

Laboratory centrifuges used to prepare platelet-rich plasma
Preparation matters: the starting blood volume, centrifugation protocol and collection method influence the final PRP.
Gloved hand holding a syringe of concentrated autologous biologic
The final syringe volume alone does not tell you the platelet dose or biologic composition.

Why Formulation Matters

“PRP” is a category, not a single drug

Two syringes can both be labeled PRP while containing very different total platelet doses and white-cell profiles. That variability is one reason clinical studies do not all produce the same result.

Total platelet dose

The number of platelets delivered may matter more than simply the concentration multiple or syringe volume. Recent knee-OA reviews show a dose-response signal.

Leukocyte profile

Leukocyte-poor and leukocyte-rich PRP are biologically different. The preferred formulation depends on the joint, tendon and clinical goal.

Target & diagnosis

A knee joint with osteoarthritis, an irritated tendon and an injured ligament are not the same biologic problem and should not automatically receive the same protocol.

Accurate placement

Ultrasound guidance allows real-time targeting rather than relying on surface landmarks alone, especially around tendons and smaller structures.

An honest note: PRP is not a miracle injection. It can improve pain and function in selected musculoskeletal conditions, but outcomes vary by diagnosis and preparation. It does not reverse advanced mechanical deformity, reliably regrow an arthritic joint surface, or replace surgery when surgery is the more predictable option.

Research & Evidence

Why PRP studies can disagree

Preparation is heterogeneous

Clinical trials use different kits, blood-draw volumes, platelet doses, leukocyte profiles and injection schedules. Pooling them under one label can hide meaningful differences.

Dose matters in knee OA

A 2024 systematic review found a possible dose-response relationship in knee osteoarthritis and identified better outcomes when total platelet dose exceeded roughly 10 billion. A separate meta-analysis found high-platelet preparations produced more durable benefit than low-platelet preparations.

Not every trial is positive

Some high-quality trials, including RESTORE, found no superiority over placebo. That is why we discuss PRP by diagnosis and formulation rather than claiming that all PRP works for everyone.

Selected references: Berrigan WA, et al. Curr Rev Musculoskelet Med. 2024;17:482–497 (platelet-dose systematic review); Bansal H, et al. Am J Sports Med. 2025 (meta-analysis of randomized trials by platelet concentration); Bennell KL, et al. JAMA. 2021;326:2021–2030 (RESTORE trial). Evidence and optimal formulations continue to evolve.

PRP: What Matters More Than the Label

A useful PRP discussion should include the actual biologic formulation, not only the fact that a syringe contains plasma and platelets.

>10B
Platelet-Dose Signal in Knee OA
A 2024 systematic review identified better knee-OA outcomes above roughly 10 billion platelets; this is not a universal threshold for every condition
Variable
Leukocyte Content
PRP can be leukocyte-poor or leukocyte-rich, and the preferred formulation may depend on the tissue being treated
Real-time
Ultrasound Guidance
Imaging lets the clinician visualize the target and needle during placement
100%
Autologous
Prepared from your own blood during the treatment visit

Explore Related Care

Related care

2-Minute Check

Am I a candidate for PRP treatment?

Answer a few quick questions. This is educational and is not a diagnosis — only an evaluation can tell for sure.

Do you have early arthritis or a tendon injury?

Would you like to explore non-surgical options before considering surgery?

Have you either not yet tried, or not responded to, other conservative care?

Answer all 3 questions to see your result.

Questions, Answered

Frequently asked questions

What is PRP?+

Platelet-rich plasma is prepared from your own blood. A centrifuge separates and concentrates platelets into a smaller volume that is then delivered to the treatment target. Platelets release signaling proteins and growth factors involved in inflammation and tissue repair.

Is all PRP the same?+

No. PRP is a category, not one standardized product. The total platelet dose, platelet concentration, leukocyte content, final volume, preparation system and the patient’s baseline blood count can all change what ends up in the syringe. The diagnosis and accuracy of injection placement matter too.

Does the number of platelets matter?+

For knee osteoarthritis, recent systematic reviews suggest a dose-response relationship, with higher platelet doses associated with better outcomes in several studies. One 2024 review identified a signal above roughly 10 billion platelets for knee OA, but that threshold should not be assumed to apply to every tendon, joint or diagnosis.

What is leukocyte-poor versus leukocyte-rich PRP?+

Some PRP preparations contain relatively few white blood cells and others contain more. The preferred formulation may depend on the tissue being treated. For example, leukocyte-poor PRP is commonly studied for intra-articular knee osteoarthritis, while the ideal formulation for tendon disorders is less settled.

Does PRP cure arthritis or regrow cartilage?+

No. PRP may reduce pain and improve function in selected patients, but it should not be marketed as a cure or as a proven way to regrow an arthritic joint surface.

Is PRP covered by insurance?+

Usually not. We'll explain the cost clearly before any treatment.

How many injections will I need?+

It depends on the diagnosis, formulation, dose and response. Some protocols use a single injection while others use a short series. We individualize the plan rather than assuming every PRP treatment should be identical.

Why use ultrasound guidance?+

Live ultrasound lets the clinician identify the target and watch the needle reach it in real time. This is particularly useful around tendons, small joints and other structures where millimeters matter.

Wondering whether PRP fits your diagnosis?

We evaluate the tissue problem, imaging, treatment history and whether an orthobiologic is likely to add value — not simply whether an injection can be offered.

Am I a Candidate? → Call (808) 439-6201
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