PLATELET-RICH PLASMA (PRP), HYALURONIC ACID (HA) AND COMBINATION THERAPY FOR KNEE OSTEOARTHRITIS (KOA)
Knee osteoarthritis (KOA) is a prevalent degenerative joint disease that affects millions worldwide, leading to pain, stiffness, and functional limitations. While traditional treatments like nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroid injections have been commonly used, they often provide only temporary relief and may have side effects with long-term use. As leaders in Orthobiologics therapies such as Platelet-Rich Plasma (PRP) and Hyaluronic Acid (HA) Viscosupplementation injections our PLYMOUTH MEDICAL team has seen them gain popularity as alternatives along our 14 year history. Some clinicians have also explored combining these treatments to enhance outcomes. This blog post delves into the efficacy of PRP, HA, and their combination in treating KOA, examining clinical evidence to determine the most effective approach. [1] [2]
Understanding the Treatments
PRP: PRP is derived from a patient's own blood, processed to concentrate platelets and growth factors. These components are then injected into the affected joint to promote tissue repair and reduce inflammation. PRP has been shown to stimulate collagen production and improve cartilage quality, offering potential long-term benefits for KOA patients.
HA: HA is a naturally occurring substance in the body that acts as a lubricant and shock absorber in joints, like the knee. [1] In a healthy joint, HA acts as a lubricant, allowing the joint to move smoothly. In OA, the amount of HA in the joint fluid decreases, leading to reduced lubrication and increased pain and stiffness. To replenish the lost natural HA, a synthetic form of HA is injected into the joint. Injections of HA into the knee joint aim to restore its viscosity, reduce friction, and alleviate pain [3] HA injections are commonly used for their immediate symptomatic relief, though their effects may be temporary.
Combination Therapy (PRP + HA): Combining PRP and HA involves administering both treatments into the joint, with the hypothesis that the regenerative properties of PRP can complement the lubricating effects of HA, leading to enhanced pain relief and functional improvement.
Comparative Efficacy
PRP vs. HA: Several studies have compared the efficacy of PRP and HA injections in treating KOA. A meta-analysis of 15 randomized controlled trials involving 1,314 patients found that PRP injections resulted in more significant pain reduction and functional improvement than HA injections at 6 and 12 months follow-up. [4] The study concluded that PRP might be more effective than HA for long-term pain relief and functional enhancement in KOA patients .
Combination Therapy: Research on the combination of PRP and HA injections has yielded promising results. A systematic review and meta-analysis of 10 studies involving 983 patients indicated that dual therapy with PRP and HA led to significant reductions in pain and improvements in function compared to PRP alone, particularly at 4-6 weeks and 12 months post-treatment. [5] Another study involving 943 patients reported that combination therapy resulted in more pronounced pain and functional improvement than HA monotherapy, with a lower incidence of adverse events compared to PRP alone. [6]
Despite these encouraging findings, some studies have reported mixed results regarding the added benefit of combining PRP with HA, particularly when compared to PRP alone in the short term (up to 12 months). A meta-analysis of 13 articles including 1,118 patients found no clinically meaningful difference between combination therapy and PRP alone in VAS, WOMAC, KOOS, and IKDC scores at 1, 3, 6, and 12 months, and concluded that PRP + HA therapy does not offer superior pain relief or functional improvement over PRP monotherapy in patients with knee osteoarthritis. [7] Similarly, a systematic review of 6 studies, consisting of 544 participants, concluded that PRP + HA therapy yields outcomes similar to PRP alone in the short term (up to 12 months), but may offer superior results at longer-term follow-up, particularly at 24 months. [8]
Safety Considerations
All three treatment modalities - PRP, HA, and their combination - are generally well-tolerated. Adverse events are typically mild and transient, including swelling, redness, or temporary pain at the injection site. Notably, combination therapy has been associated with a lower incidence of adverse events compared to HA or PRP monotherapy. [6,7]
Cost and Accessibility
The cost of these treatments can vary based on geographic location, healthcare provider, and the number of injections required. PRP therapy tends to be more expensive due to the preparation process and the use of autologous blood. Many HA injections, such as GENVISC® 850 and TRIVISC® are generally more affordable and sometimes covered by insurance. Combination therapy may incur additional costs but could potentially offer more cost-effective long-term outcomes by reducing the need for repeated treatments. At $97 per injection direct to the patient, PLYMOUTH MEDICAL’s HA is often times more affordable than their deductible and copays.
Conclusion
For patients with knee osteoarthritis seeking effective, minimally invasive treatment options, PRP injections offer superior long-term pain relief and functional improvement compared to HA injections. [4] While combination therapy with PRP and HA was generally associated with a lower incidence of adverse events, it was not consistently superior to PRP alone in terms of pain relief and functional improvement in the short term (up to 12 months). However, several studies suggest that combination therapy may offer superior outcomes in the longer term, particularly at 24-month follow-up. Taken together, the evidence suggests that combination therapy provides the best balance of safety and efficacy, but if a single treatment must be selected, PRP should be prioritized. It is important to note, however, that the meta-analyses referenced include a wide range of PRP preparations and HA formulations, varying in platelet concentration, molecular weight, and origin—highlighting the need for further research that standardizes and evaluates these variables to better guide clinical decision-making.
Ultimately, the choice between these treatments should be individualized, considering factors such as disease severity, patient preferences, and cost considerations. Consultation with a healthcare provider specializing in musculoskeletal disorders is essential to determine the most appropriate treatment plan.
Citations
05/25/2025