Can PRP Injection (Platelet-Rich Plasma) Effectively Treat Chronic Running Injuries?
Guest blog by John Davis (RunnersConnect)
In the past decade, several emerging treatments for chronic overuse injuries have been getting a lot of attention in the running community. Chief among these is platelet-rich plasma injections or PRP, a procedure that attempts to use cells from your own blood to restart the healing process.
Platelet-rich plasma injections promise a new avenue of treatment for runners with longstanding recalcitrant injuries, which have failed standard treatment protocols like long periods of rest, custom orthotics, or rehab exercises prescribed by a physical therapist. Although PRP is very new and is still considered an experimental treatment by most doctors, it is nevertheless being touted by less-cautious providers and has gained something of a following in the running community.
To get a better understanding of what PRP can and cannot do, we’ll turn to the scientific literature for some answers.
Platelet-rich plasma as healing aid
Platelet-rich plasma has been studied as a healing aid in several fields of medicine; its initial uses were in orthopedic surgery, where doctors found it boosted healing and decreased blood loss after invasive surgeries like total knee replacements.
By “spinning” samples of a patient’s own blood in a centrifuge, doctors could separate the red blood cells from the platelets, small cells which boost healing and help form clots. A second centrifuging concentrates the separated platelets and plasma, creating the platelet-rich plasma solution.
This liquid contains growth factors and proteins that are thought to jump-start the healing process in injured or degenerated tissue, and given the success of PRP in orthopedic surgery, it was investigated as a treatment for chronic overuse injuries in athletes.
As PRP is a fairly new treatment, there are only a handful of studies on using it to treat specific injuries. Additionally, only a few of them have any of the features of a strong clinical trial: control groups, reasonably large sample sizes, and good experimental design. As an example, we’ll look at a study carried out by Joost Peerbooms and colleagues at HAGA Hospital in the Netherlands.
PRP injection for running injuries
Though Peerbooms et al. looked at using PRP to treat lateral epicondylitis (tennis elbow) in this study, similar papers have examined using PRP to treat Achilles tendonitis, plantar fasciitis, and patellar tendonitis, all injuries of interest to runners. Peerbooms et al. split a group of 100 patients with chronic tendon pain at their elbow into an experimental group and a control group.
The experimental group received a PRP injection into the painful tendon, while the control group received a similar injection of a corticosteroid anti-inflammatory drug. After the injection, the patients received four weeks of physical therapy before being allowed to return to sport.
When the researchers checked in with the patients one year after the treatment, they found that 49% of the control group had made a successful recovery, compared to 73% of the group which received the PRP injection.
While similar studies—albeit mostly smaller and sometimes without a control group—have found PRP useful in the treatment of chronic Achilles tendonitis, patellar tendonitis, and plantar fasciitis as well, not all studies have had success. One well-designed study by Robert de Vos and others at Erasmus University in the Netherlands assessed a group of 54 patients with Achilles tendonitis; half were treated with a PRP injection, while the other half got a placebo injection of saline solution.
While both groups had significant improvements in their Achilles tendon over the course of the 24-week study, there was no significant difference between the groups.
Administration and side effects
In the coming years, it is likely that we’ll see more large studies on PRP. The amount of them which will show a benefit is unclear, but given the research done to date, it’s likely that platelet- rich plasma therapy will gain a place as a treatment protocol with at least some chance of success at rehabilitating chronic overuse injuries.
The biggest questions about PRP surround the specifics of how and when to administer the treatment, as well as how much it can be expected to help. As discussed in a review article by Timothy Foster and other doctors at a range of hospitals across the United States, platelet-rich plasma injections show much promise as a future treatment for a range of injuries, but a lot more research is needed.
Foster et al. criticize a “rampant lack of standardization” of treatment protocols, meaning that different providers often won’t employ the same methods and dosages when injecting platelet-rich plasma!
They also caution that a PRP injection causes fairly dramatic inflammation at the site of the injection, and often causes the patient “discomfort”—though to what extent, they do not say. The authors encourage liberal icing after a PRP injection, and note that most studies recommend a 6-8 week rehabilitation period before returning to sport.
PRP treatment’s reliability
To be clear, platelet-rich plasma injections are a promising but very much still experimental treatment.
- To date, the only running injuries that have shown some response to PRP treatment are Achilles tendonitis, patellar tendonitis, and plantar fasciitis.
- Though PRP is generally regarded as a safe treatment (as it involves injecting an extract of your own blood), it can still cause significant pain and enough trauma to warrant a 6-8 week recovery period, and there are no studies possible long-term effects.
Because of this, and because of the limited number of high-quality studies demonstrating successful treatment of overuse injuries with PRP, it should be thought of as an intermediate step between conservative treatments like extended periods of rest, orthotics, and rehabilitation with stretching and strengthening exercises and more invasive treatments like surgery.
It’s highly unlikely that insurance will cover a PRP injection, and unfortunately the treatment protocol has not yet been standardized: there’s no guarantee that a local PRP injection provider that you find will employ the same method of treatment that is used in the most advanced scientific studies.
Runners with longstanding, recalcitrant overuse injuries in their plantar fascia, Achilles tendon, or patellar tendon which have not responded to eccentric exercise, rest, and other conservative treatments might consider getting a PRP injection, but you should be aware that even the most promising studies indicate that some patients do not respond to platelet-rich plasma injections.