We know that hyaluronic acid injections and PRP therapy can help reduce symptoms related to hip osteoarthritis. But is one better than the other OR do you get even better results by mixing the two together? This recently published clinical trial compared the effects of PRP injection alone vs hyaluronic acid injection alone vs the two combined together. And they wanted to know which group had the best results for treating hip osteoarthritis. Let’s look at what they found.
Hyaluronic acid injections and PRP injections work through different mechanisms. So it’s theorized that combining the two together will give us synergistic effects and better outcomes. That’s why many physicians recommend when you get a PRP injection, that you also add in hyaluronic acid. But is there any evidence to support this practice?
That’s what this new clinical trial tried to answer. They had a final enrollment of 92 patients that were randomized to one of three groups: PRP alone, hyaluronic acid alone, or the two combined together. These patients all had mild to moderate hip osteoarthritis and were given two injections spaced two weeks apart. All injections were administered ultrasound guided.
For the PRP group, patients had 35 cc’s of blood drawn which were then concentrated down to a total volume of 5 cc’s of PRP. This gave an average of 7 billion platelets per injection. No activating agents were used in their PRP.
For the hyaluronic acid group, a high molecular weight HA preparation was used. And for the combined group, the subjects first got the 5 cc of PRP followed immediately by the HA injection. The authors followed these patients and measured outcomes at 2 months and 6 months following the second injection.
So what did they find? The first thing to note is that all three groups had meaningful improvements at 2 months and at 6 months compared to baseline. This of course is NOT surprising as we already knew that HA and PRP injections work well to control symptoms related to hip osteoarthritis. The question we want to answer is how do they compare to each other?
So the authors found that the PRP group and the PRP plus HA group had better outcomes when compared to the HA alone. This means that PRP injections provide better symptoms and better functional improvements than HA injections. And what about combining the two together? The authors report that when they compared the PRP group to the PRP PLUS HA group, they found that there were no differences in outcome measures between the two groups.
The authors went on to conclude that PRP is SUPERIOR to HA for improving function and disability related to hip osteoarthritis. They also conclude that adding HA to PRP had no additional benefits to outcomes.
So we now have multiple randomized controlled trials as well as systematic reviews and meta-analysis that all conclude that PRP injections are superior to hyaluronic acid injections when it comes to reducing symptoms related to hip osteoarthritis.
This is why in a previous video where I go over my most recommended treatments for hip osteoarthritis, PRP has a higher ranking than hyaluronic acid injections. Now that’s not to say that HA injections don’t work, remember, in the study, all three groups showed improvements. It’s just that HA injections are not as good as PRP injections. With that said, they are still much much better than cortisone injections.
Previous studies have shown that even one cortisone injection into the hip can significantly increase the risk of developing worse arthritis and rapidly destructive hip disease. So even though HA injections are not as good as PRP injections, it’s still better than corticosteroid injections, especially if it’s covered by insurance.
And what about combining PRP and HA? Well we now have a clinical trial that says combining the two at the time of injection does not change outcomes. So does this mean that if you get PRP injections you should not get any more HA injections?
Well, maybe. If you can afford to get multiple PRP injections throughout the year if you need them, then yes, you may not need to get HA injections anymore. Just get the PRP.
But, for many other people, especially if their insurance will cover HA injections, it makes sense to take advantage of a covered benefit. But instead of administering the HA and the PRP at the same time, I would space them out.
For example, if you are getting PRP injections once a year or once every 6 months. Then you may want to add HA injections at months 3 and months 9 regardless of whether you are having symptoms or not. The HA injections here are meant to be maintenance therapy. And the purpose of doing this is to try to keep the microenvironment of the arthritic joint as healthy and as neutral as possible.
Remember, one of the reasons that osteoarthritis progressively gets worse is because of the release of toxic enzymes and proteins as well as inflammatory cytokines into the joint. This creates an incredibly inflammatory environment that leads to cartilage damage and pain. So by staggering the PRP and the HA, the goal is to reduce the levels of inflammation in the joint and try to protect the cartilage. This will not only reduce symptoms, but hopefully decrease the progression of arthritis.