Platelet-rich plasma (PRP) is also known as blood injection therapy. PRP refers to a sample of serum (blood) plasma taken from the patient being treated. The plasma is then injected into the symptomatic (painful or tender) area.
Platelet-rich plasma has as much as four times more than the normal amount of platelets. Platelets contain growth factors that act to promote tendon repair. These growth factors send signals to the body that increase blood flow to the area and transport cellular debris and waste from cellular metabolism away from the tissue.
This treatment enhances the body’s natural ability to heal itself. It is used to improve healing and shorten recovery time from acute and chronic soft tissue injuries. Most of the work done and studies reported have been on acute injuries, especially tennis elbow. But results from research into the use of platelet-rich plasma with chronic problems is slowly starting to trickle in.
There is a recent study from The Netherlands that may have some answers for you. In this study, orthopedic surgeons used platelet-rich plasma (PRP) to treat chronic Achilles tendinopathy. The study included a second (control) group of patients who received an injection of saline instead of PRP. Results were reported six months after the single injection and again now at the end of a full year.
They used the standard tests of joint motion, recording the presence and intensity of pain, and assessing function to report on outcomes of treatment. But they also went a step further in actually looking at the tendon fibers.
They used a recently validated technique called ultrasonographic tissue characterization (UTC). This is an imaging technique that allows for assessing the condition of individual tendons. It gives a three-dimensional view of the tendon structure. The ultrasonic view of the tendon also made it possible to measure the quality of blood vessels and blood supply to the area (referred to as neovascularization of the tendon).
In addition to asking patients about their level of satisfaction with the treatment, ultrasound measurements were taken before and after treatment. What did they find? There wasn’t a measurable difference between the two groups (one treated with platelet-rich plasma and the other with saline).
Both groups were equally satisfied with the results. Both groups had an equal amount of tendon healing and blood flow as shown by the ultrasound testing. The only measurable difference was in terms of return-to-sports. There were more patients in the platelet-rich plasma group (56.5 per cent) who went back to their previous sport compared with the saline (control) group (41.7 per cent).
These results were pretty much the same as the results reported six months after the injection. There are two possible reasons why the two groups had similar results. The first is the fact that both groups had an injection and it might not be the contents of the needle (plasma versus saline) as much as it is the effects of the needle entering the area. And secondly, patients in both groups performed an exercise program for three months. It is possible the exercise program had as much to do with the results as anything else.
The results of this study did not support the use of platelet-rich plasma for chronic Achilles tendon problems. More study is needed before this treatment will be approved for all tendon problems. For example, it may be necessary to compare PRP injections alone with exercise alone to see the true effects of each individual treatment. For now, the exercise program seems to have the best results and remains a standard part of treatment for this problem.