CHICAGO — New research casts doubt on increasingly popular blood-based injections reportedly used by Tiger Woods and other athletes to speed recovery after orthopedic surgery.
In a small study at a hospital in The Netherlands, the treatment worked no better than salt water injections in patients with Achilles tendon overuse injuries.
The Achilles is the body’s largest tendon, connecting calf muscles in the lower leg to the heel bone and it’s prone to overuse injury from sports, including running.
The treatment studied involves injections of platelet-rich plasma, or PRP, extracted from patients’ own blood. Platelets help blood clot and they release growth-promoting substances that help repair damaged tissue.
Tiger Woods is reported to have had these injections after June 2008 knee surgery.
In the study, 27 adult patients got PRP injections and 27 got injections of salt water. A week after the injections, both groups gradually began three months of exercise therapy including stretching.
Six months after treatment, both groups reported the same amount of improvement in pain and activity levels.
The results appear in Wednesday’s Journal of the American Medical Association.
Patients were treated at The Hague Medical Center. The study authors called the results disappointing but also called for more research and said it’s possible the platelet treatment works for other types of injuries.
I’ve seen proof that it works as well for bone/tendon/muscle injections - and i’m perplex regarding the method used : “treatment worked no better than salt water injections in patients with Achilles tendon overuse injuries.” Was it necessary to inject anything for the control group? Also, Achilles tendon injury might not be the best one for this kind of studies - the largest tendon as they say - and one with many grades of injury. Furthermore, after the tissue is repaired, the rehab to get the founction back is very long, regardless the method used to repair.
Yes, it is necessary to inject the control group, as you may otherwise be looking at non-specific effects of inflammation caused by an injection of any substance. Prolotherapy, for example, works by injecting an irritant that causes inflammation which results in formation of collagen (scarring) thus strengthening weakened tendons and ligaments.
Another very important issue, of course, is the placebo effect. A person not receiving an injection would know that they are not being treated and thus not expect to get better.
I can’t comment on differences in protocol and skill levels between different practitioners, but it is possible that the anecdotal evidence of effectiveness Charlie and you describe may have been due to such a placebo effect.
Alternatively, the improvement observed may also have been due to other treatment modalities used concurrently. All these factors need to be controlled for in a good study, which seems to have been the case with this one.
Having looked at the actual study, it seems to have been quite well designed. The patients were suffering from chronic tendinopathy (so may have had symptoms for longer than the athletes you and Charlie are referring to). The last assessment took place 24 weeks after intervention, so long-term follow-up was done. The treated patients did report slightly more improvement (score of 21.7 vs 20.5), but this difference was not significant. The injections were conducted by a sports medicine physician and “the PRP preparation and injection was performed as the usual generally accepted procedure in daily clinical practice.”
For all the sportsmen/women (including athletes) i’m talking about, this was chronic as the other treatment failed (none of them were Achilles injury). PRP injections are not used in “first intention” in my coutry. I don’t know if it’s the case in Netherland, but what makes me perplex is that they would give salt water (placebo) to professional athletes having chronic syndrome where first treatment failed, for the sake of science.
