running problem athlete training outdoors tendons achilles
What sort of injections help Achilles tendonosis? (Warren Goldswain)

Are Prolotherapy or PRP Injections Worth It?

I’ve been having trouble with Achilles tendinosis, so a friend mentioned that I should look into prolotherapy. What’s the difference between that and PRP, and is it worth it?

running problem athlete training outdoors tendons achilles

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We posed your question to Dr. Mark Darrow, owner of the Prolotherapy Institute in Los Angeles and an assistant professor at the University of California, Los Angeles.

Both prolotherapy and PRP are injections of substances that are supposed to “give a quick burst of high inflammation that stimulates a healing cascade,” Darrow says. Tendinosis, in particular, is marked by a lack of inflammation, indicating the healing process in that area has slowed or halted, leaving behind unrepaired tissue. The inflammation created by the injected material is thought to hasten healing by encouraging the regeneration of new, healthy tissue, including collagen (what tendons are made of) and cartilage.

The difference between prolotherapy and PRP is what’s being injected. In prolotherapy, dextrose, or sugar water, is injected to create inflammation in the painful tendon, muscle, joint, or ligament. In PRP, your own plasma, the part of the blood containing growth factors thought to promote healing, is injected. The average prolotherapy treatment, Darrow says, takes four to six injections, while PRP works more quickly, typically taking only two to four injections.

But at about $295 a pop for prolotherapy and $800 for PRP, those injections are pricey, and most often not covered by insurance because researchers have yet to adequately prove the effectiveness of these therapies. One study, published in 2011, found that in the long term prolotherapy was no more effective at reducing symptoms of Achilles tendinosis than doing eccentric loading exercises like calf raises.

Whether these injection therapies are worth the expense and uncertainty is up to you. But it’s worth noting that more and more professional athletes, including Kobe Bryant, Tiger Woods, and Alex Rodriguez, have been turning to PRP to help with problems like knee pain, Fox Sports reports. Portland guard Brandon Roy, Fox says, credits PRP for a career comeback after chronic knee problems forced him into early retirement at 27 years old.

From Outside Magazine, April/May 2021 Lead Photo: Warren Goldswain