What is the evidence for using Platelet-rich plasma (PRP) therapy for knee pain?

From the Guidelines

Platelet-rich plasma (PRP) therapy for knee pain shows moderate evidence of effectiveness, particularly for osteoarthritis, and should be considered as part of a comprehensive treatment approach. PRP involves drawing a patient's blood, processing it to concentrate platelets, and injecting this concentration into the knee joint. Typical protocols include 1-3 injections spaced 1-4 weeks apart, with possible maintenance injections every 6-12 months. Most studies show PRP provides better pain relief and functional improvement compared to placebo and hyaluronic acid injections, with benefits lasting 6-12 months 1. The biological mechanism involves platelets releasing growth factors that reduce inflammation and potentially stimulate tissue healing.

Key Considerations

• Side effects are generally mild and include temporary pain at the injection site and swelling.
• PRP works best for mild to moderate osteoarthritis rather than severe joint damage, and results vary between patients.
• Insurance typically doesn't cover this treatment, with costs ranging from $500-$2,000 per injection.
• A comprehensive treatment approach should include physical therapy and appropriate activity modification, as suggested by the 2020 US Department of Veterans Affairs/US Department of Defense clinical practice guideline 1.
• The evidence supporting the use of physical therapy as a core treatment in the management of OA is substantial, and bracing with soft braces or either valgus or varus knee braces may improve pain and self-reported physical function in the knee 1.

Treatment Approach

• PRP therapy should be considered for patients with mild to moderate osteoarthritis who have not responded to other treatments, such as physical therapy, oral nonsteroidal anti-inflammatory drugs, and acetaminophen.
• Patients should be informed about the potential benefits and risks of PRP therapy, including the cost and lack of insurance coverage.
• A comprehensive treatment approach should be individualized to each patient's needs and should include a combination of non-pharmacological and pharmacological interventions.

From the Research

PRP for Knee Pain Evidence

There are no direct studies provided on the effectiveness of Platelet-Rich Plasma (PRP) for knee pain. However, the following information on knee pain management can be gathered from the available studies:

• The most common causes of knee pain are osteoarthritis (OA), patellofemoral pain, and meniscal tears 2.
• First-line management of OA comprises exercise therapy, weight loss (if overweight), education, and self-management programs 2, 3, 4.
• Conservative management, including exercise therapy, is also appropriate for most meniscal tears and patellofemoral pain 2, 5.
• Non-surgical treatment options for knee OA, such as non-steroidal anti-inflammatory drugs (NSAIDs), weight loss, intra-articular injections, physical therapy, and bracing, have been shown to be effective 3, 4, 5.
• The American Society of Pain and Neuroscience has presented guidelines on interventional therapies for knee pain, including physical therapy, pharmacologic agents, and interventional pain procedures 6.

Treatment Options for Knee Pain

Some key points to consider for knee pain management:

• Exercise-based therapy is the foundation for treating knee osteoarthritis and patellofemoral pain syndrome 2, 5.
• Weight loss should be encouraged for all patients with osteoarthritis and a body mass index greater than 25 kg per m2 2, 5.
• Corticosteroid injections are effective for short-term pain relief in patients with osteoarthritis 5.
• The benefit of hyaluronic acid injections is controversial, and recommendations vary 5.