Platelet Rich Plasma (PRP) is a treatment option for sports injuries or joint pain, most commonly for tendonitis or ligament strains, but also for recent broken bones and cartilage damage. Although the use of PRP is becoming de rigueur for professional athletes and well-accepted by sports physicians, most people are unaware of what it is and how it is used.
Traditional care for joint injuries starts with resting and rehabilitating the injury. For many people this is all that is needed, but those with more severe injuries or injuries that refuse to heal properly, the next step is surgery - and that's a pretty big step.
Ideally we'd like to stimulate the body to repair the injury on its own without having to resort to cutting the joint open and mechanically repairing it - surgeries typically come with long down times and significant risk of complications, including increased risk of blood clots, infection and arthritis in the years following the surgery.
The tendons, ligaments and cartilage found in joints all have poor blood supplies and thus, heal slowly. The theory behind PRP is that after an injection of concentrated platelets into the area of injury, the platelets will secrete regenerative factors and hormones that hasten the body's healing processes, much in the way that they stimulate repair after you cut your skin.
PRP is very natural and gentle process compared to a pharmaceutical or surgical based procedure. The physician starts by collecting about two tablespoons of blood; the blood is centrifuged to extract as many platelets and growth factors as possible while discarding the red blood cells and, depending on the physician's methods and aims, the white blood cells as well. The platelets are suspended in a small volume of the patients own blood plasma and injected into the affected area. Other than the patient's blood, the only chemical required by the procedure is a tiny amount of anticoagulant citrate, without which the blood would clot before processing could be completed.
Commonly, lidocaine is used to make joint injection more comfortable. Usually it is not mixed into the PRP, but is injected into the tissues to numb them just before the PRP injection. Some physicians will infuse the PRP with other drugs or hormones before injection, but this is an adjunct to the PRP therapy and not mandatory for all patients. PRP is also commonly used as a carrier for autologous stem cells derived from the patient's own adipose tissue (fat) or bone marrow.
There are a number of methods used for extracting PRP from whole blood. The biggest difference is that some include the white blood cells (WBCs) and some discard them. This is important because joints that have been injected with PRP including WBCs usually feel stiff and painful for weeks after the injection. Proponents of including the WBCs say an inflammatory response, with the resultant pain, is necessary to achieve maximum healing. Others, including Dr. Gelber, haven't seen better results from including WBCs and prefer not to include them.
There has been a lot of good research on PRP at the lab level, but large controlled studies haven't been completed yet. Doing so will be a complicated task - there are many different types and gradations of joint injury, and pain does not always correlate with the extent of the damage. As a result, any study of PRP will have to be very large (read, expensive) to achieve statistical significance. Unfortunately, since any regenerative effect will not be attributable to a patentable (profitable) pharmaceutical or device there is little incentive for a company or person to carry out such a study.
Until these studies are completed, insurance companies are unlikely to reimburse PRP therapy and it will continue to be a medical procedure available only to professional athletes and those who can afford to pay out-of-pocket for the chance at improved healing and pain without the downtime and risks of surgery.