Ask Dr. C Episode 16: Is PRP+HA>PRP for Knee Arthritis?
Today I’ll cover an interesting issue. Does adding hyaluronic acid to PRP make the PRP more effective? This is an interesting one.
What Is PRP?
PRP stands for platelet-rich plasma. That’s when your blood is taken and the platelets are separated out, concentrated, and then delivered back to you. These platelets have healing growth factors so PRP can aid in tissue healing.Request a Regenexx Appointment
Does Adding HA to PRP Boost Pain Relief?
This is an interesting and great Ask Dr. C question. HA stands for hyaluronic acid. You may know this as the knee gel shots that doctors offer to help arthritis pain. This stuff is basically artificial joint fluid used to lubricate the joint, but also to improve the chemical make-up of the arthritic joint fluid which is often poisoned by too many inflammatory breakdown chemicals.
First, when we compare the efficacy of PRP to HA in treating knee arthritis, we have enough randomized controlled trials to show that PRP works better than HA (2). Basically, the effects generally last longer and there is better pain relief and function.
So is adding HA to PRP better than PRP alone? This is a reasonable question to ask. Each seems to work on its own to help knee arthritis in different ways, so would adding the two together work better?
A recent study out of Asia looked at 122 knees with osteoarthritis and found that the PRP+HA group did better on pain and function at 2 years after the injection than did the PRP or HA injection groups (1). In addition, there were fewer pro-inflammatory chemicals in the PRP+HA group.
Does this trend for PRP+HA being better than PRP alone hold across multiple studies? There is a meta-analysis, which means a study that aggregates data from multiple other studies to see if the combined data tells a story. In this case, the meta-analysis included 7 studies with 941 patients that compared PRP+HA vs. PRP to treat knee arthritis (3). The PRP+HA worked better than PRP alone.
So in conclusion, PRP+HA seems to work better than PRP alone when treating knee arthritis. This issue isn’t 100% settled yet. In addition, the meta-analysis is new this year, so this is a relatively recent finding.
One thing that readers should keep in mind is that all of these studies used what I call low or mid-dose PRP, which is a product concentrated at 2-7X over baseline. Meaning if the patient began with a platelet count in their blood of 300, then if the post concentrated platelet count is 600 that’s 2X and if it’s 900, that’s 3X. At Regenexx, for kee arthritis patients we use PRP that’s 10-20X. Our most common dose is 14X. Hence, it’s unknown how HA+PRP would compare to a much higher dose of PRP.
On a personal note, I have used PRP+HA in select patients. I’m still not personally sure if it’s dramatically more effective, but I will certainly take note of this new research.
The upshot? In answering this question for this reader, it turns out that there is new information out there about PRP+HA since the pandemic began. So I really appreciate this question! Will HA+PRP become the standard? I can certainly say that my next step is to use this combo in more patients and see if it works well enough in the real world to change our existing clinical practices!
(1) Xu Z, He Z, Shu L, Li X, Ma M, Ye C. Intra-Articular Platelet-Rich Plasma Combined With Hyaluronic Acid Injection for Knee Osteoarthritis Is Superior to Platelet-Rich Plasma or Hyaluronic Acid Alone in Inhibiting Inflammation and Improving Pain and Function. Arthroscopy. 2020 Oct 20:S0749-8063(20)30843-4. doi: 10.1016/j.arthro.2020.10.013. Epub ahead of print. PMID: 33091549.
(2) Tan J, Chen H, Zhao L, Huang W. Platelet-Rich Plasma Versus Hyaluronic Acid in the Treatment of Knee Osteoarthritis: A Meta-Analysis of 26 Randomized Controlled Trials. Arthroscopy. 2020 Jul 15:S0749-8063(20)30604-6. doi: 10.1016/j.arthro.2020.07.011. Epub ahead of print. PMID: 32679294.
(3) Zhao J, Huang H, Liang G, Zeng LF, Yang W, Liu J. Effects and safety of the combination of platelet-rich plasma (PRP) and hyaluronic acid (HA) in the treatment of knee osteoarthritis: a systematic review and meta-analysis. BMC Musculoskelet Disord. 2020 Apr 11;21(1):224. doi: 10.1186/s12891-020-03262-w. PMID: 32278352; PMCID: PMC7149899.