PRP Injections for Joint Pain: What the Research Actually Shows

Key Takeaways

• PRP injections use your own blood platelets to potentially reduce joint pain and promote healing
• Research shows mixed results - some studies show modest benefit, others show no advantage over placebo
• The FDA has not approved PRP for arthritis treatment, and quality standards vary widely between providers
• Medicare and most insurance plans don’t cover PRP, with costs ranging from $500 to $2,000+ per injection
• FDA-approved alternatives like hyaluronic acid injections offer more consistent results with insurance coverage

If you’ve been researching options for knee or joint pain, you’ve probably come across platelet-rich plasma (PRP) injections. They’re marketed as a cutting-edge “regenerative medicine” treatment that can heal damaged joints naturally.

But what does the actual research say? Let’s separate the marketing claims from the medical evidence.

What Are PRP Injections?

Platelet-rich plasma (PRP) is made from your own blood. Here’s how the process works:

1. A healthcare provider draws your blood (similar to a regular blood test)
2. The blood is placed in a centrifuge machine that spins at high speed
3. This spinning separates the blood into layers
4. The platelet-rich layer is extracted and concentrated
5. This concentrated plasma is injected into your painful joint

The entire process typically takes 30 to 60 minutes. Most providers recommend a series of 1 to 3 injections spaced weeks apart.

The Theory Behind PRP

Platelets are tiny blood cells best known for helping blood clot when you get a cut. But they also contain hundreds of proteins called growth factors.

The theory is that injecting a concentrated dose of these growth factors into an arthritic joint might:

• Reduce inflammation
• Stimulate cartilage repair
• Promote tissue healing
• Decrease pain signals

It sounds promising. But does it actually work?

What the Research Actually Shows

Here’s where things get complicated. The research on PRP for arthritis is mixed at best.

Studies Showing Modest Benefits

Some studies have found that PRP provides better pain relief than no treatment or saline injections. A 2021 review of multiple studies found that PRP may offer short-term pain relief for mild to moderate knee osteoarthritis.

The improvements, when they occur, are typically modest - not the dramatic “regeneration” some marketing materials suggest.

Studies Showing No Benefit

Other well-designed studies have found no significant difference between PRP and placebo injections. A 2022 clinical trial published in JAMA found that PRP was no better than saline injections for knee arthritis pain after one year.

A 2023 systematic review concluded that the evidence for PRP in knee osteoarthritis remains “inconclusive” due to inconsistent study results.

Why the Inconsistent Results?

Several factors make PRP research difficult to interpret:

No standardized preparation method - Different providers use different equipment and techniques to prepare PRP. This means the concentration of platelets and growth factors varies widely from clinic to clinic, and even from injection to injection.

Patient selection varies - Some studies include patients with mild arthritis, others include severe cases. PRP may work differently depending on the stage of joint damage.

Different study designs - Some studies are well-controlled with placebo groups, others are not. Many studies are small and funded by companies that sell PRP preparation kits.

Placebo effect is strong - Joint injections often produce temporary improvement regardless of what’s injected. This makes it hard to determine if PRP provides benefits beyond placebo.

FDA Status and Regulation

Here’s something important to know: the FDA has not approved PRP for treating arthritis or joint pain.

Because PRP is made from your own blood, it falls into a regulatory gray area. Providers can legally offer it, but it’s considered an experimental treatment.

This means:

• There are no FDA quality standards for how PRP should be prepared
• There’s no requirement for providers to prove it works
• Marketing claims don’t need to be backed by solid evidence
• The concentration and quality of PRP can vary dramatically

Some clinics use sophisticated equipment and follow research protocols. Others use basic centrifuges that may not produce consistent results. As a patient, it’s difficult to know what quality you’re getting.

Cost and Insurance Coverage

Because PRP is not FDA-approved for arthritis, Medicare does not cover it. Most private insurance plans don’t cover it either.

You can expect to pay out-of-pocket:

• $500 to $2,000+ per injection depending on your location and the clinic
• Most providers recommend 1 to 3 injections initially
• Some suggest repeat injections every 6 to 12 months

The total cost can easily reach several thousand dollars per year - with no guarantee of benefit.

Compare this to FDA-approved hyaluronic acid injections, which are typically covered by Medicare and insurance when medically appropriate. These “gel shots” have decades of research supporting their use and cost patients far less out-of-pocket.

Important Questions to Ask

If you’re considering PRP, ask your provider:

1. What equipment do you use to prepare PRP? There’s a wide range of quality in PRP preparation systems.

2. What concentration of platelets will my injection contain? If they can’t tell you, that’s a red flag.

3. What does the research show for my specific condition? Be skeptical of providers who promise “regeneration” or guaranteed results.

4. What are the FDA-approved alternatives? A good provider will discuss evidence-based options first.

5. What is your refund policy if it doesn’t work? Most clinics offering PRP have no refund policy.

Red Flags to Watch For

Be cautious of providers who:

• Guarantee results or promise to “regenerate cartilage”
• Pressure you to commit to multiple expensive treatments upfront
• Don’t discuss FDA-approved alternatives
• Use high-pressure sales tactics or time-limited “special offers”
• Claim PRP is superior to all other treatments without acknowledging the mixed research

FDA-Approved Alternatives Worth Considering

Before spending thousands on an unproven treatment, consider options with stronger evidence:

Hyaluronic acid injections (viscosupplementation) - FDA-approved for knee osteoarthritis with decades of research. Typically covered by Medicare and insurance. Studies show consistent pain relief lasting 6 months or longer.

Corticosteroid injections - FDA-approved and well-researched for reducing inflammation. Covered by insurance. Best for acute flare-ups rather than long-term management.

Physical therapy - Strong evidence for improving function and reducing pain. Often covered by insurance with a referral.

The Bottom Line

PRP injections might have a role in treating joint pain someday. But right now, the research is inconsistent, the treatment is unregulated, it’s expensive, and insurance doesn’t cover it.

For most people with knee or joint arthritis, especially those on Medicare, it makes more sense to start with evidence-based treatments that are proven to work and are covered by insurance.

If you do decide to try PRP:

• Consider it only after trying proven treatments first
• Choose a provider who is transparent about the limitations
• Be prepared for the possibility it won’t work
• Don’t let it delay more effective treatments

Your joint health is too important for guesswork. Stick with treatments backed by solid research and FDA approval whenever possible.

Frequently Asked Questions

Is PRP the same as stem cell therapy?

No. PRP uses the platelet-rich portion of your blood. Stem cell therapy uses stem cells, which are different cells that can potentially develop into various tissue types. Both are considered experimental for arthritis and lack FDA approval for joint treatment.

How long do PRP injections last if they work?

In studies that show benefit, pain relief typically lasts 6 to 12 months. However, many patients report shorter durations or no benefit at all. Results vary significantly between individuals.

Are PRP injections painful?

The injection itself is similar to other joint injections - brief discomfort that most people tolerate well. Some patients experience increased pain for a few days after the injection before any improvement occurs.

Can PRP regrow cartilage in arthritic joints?

Despite marketing claims, there is no solid evidence that PRP can regenerate cartilage in humans with arthritis. While it may reduce pain temporarily in some patients, it does not reverse arthritis or rebuild damaged cartilage.

Why doesn’t Medicare cover PRP if some studies show it works?

Medicare requires strong, consistent evidence of effectiveness before covering a treatment. The research on PRP is too mixed and inconsistent to meet their standards. Additionally, the lack of standardization means Medicare can’t ensure patients are receiving a consistent, quality treatment.

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This article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider about treatment options for your specific condition.

Last medically reviewed: March 2025