Physical Therapy in Asheville for Exercise
Haven't heard of platelet-rich plasma (PRP) to treat sports injuries? Listen up! You're not alone. Patients calling their doctors asking about this treatment for tennis elbow or other muscle or tendon injuries may be surprised when their physician has never heard of it. That's because it is relatively new, and it hasn't been tested fully to prove its effectiveness. So, there aren't many studies being published just yet. Most of the studies presented so far have been with animals or small numbers of people.
That's why orthopedic surgeons from the New York University Hospital for Joint Diseases wrote this article offering general information on the technique. First of all, what is platelet-rich plasma? Platelets are part of the blood that circulate around the body ready to help with blood clotting should you have a cut, broken bone, injury that bleeds internally, or any other type of injury. Besides containing clotting factors, the platelets release growth factors that help start the healing sequence. Plasma is the clear portion of the blood in which all the other blood particles such as platelets, red blood cells, and white blood cells travel.
So platelet-rich plasma refers to a sample of plasma that has more than the normal amount of platelets. To get this substance, a portion of the blood is removed from a patient and placed in a machine called a centrifuge. The centrifuge spins the blood fast enough to separate it into layers based on weight. Heavier parts (e.g., red blood cells) stay on the bottom. Platelets and white blood cells spin out just above the red blood cell layer. Lighter particles (plasma without platelets or blood cells) make up the top layer in the test tube.
The platelet-rich portion of the plasma is then injected into the damaged area (e.g., tendon, joint). This treatment technique isn't entirely new -- just new to the realm of sports medicine. It's been used for years after plastic surgery and surgery on the mouth, jaw, and neck. It seems to promote bone graft healing and wound healing. Researchers have found a way to combine this substance with other chemicals to make it into a putty or gel that can be painted on a surgical site to speed up healing.
The benefits of this treatment have brought it to the attention of others who have tried it for spinal fusions, bone fractures, and chronic conditions like tennis elbow. Platelet-rich plasma has also been used with positive results for patients with degenerative conditions such as osteoarthritis that result in joint damage from wear and tear.
As with any new treatment, the usual questions arise. For example, how much is needed to get a positive healing response? How many injections are needed and over what period of time? One week? One month? What's the optimal ratio of plasma to platelets for the desired accelerated healing? At first, surgeons used a mixture that contained four times the normal amount of platelets. But over time, scientists have found that less can be used with the same good results. Patients considering this treatment may wonder about the cost. New treatment techniques are often expensive and this is no different. Each injection costs about $150.00 out-of-pocket (insurance doesn't cover treatments considered experimental).
What's the evidence so far that this treatment works? Studies have been done both on animals and on humans. After using the platelet-rich plasma (PRP), tendon cells (called tenocytes) removed from the treated area have been examined. Growth factors that help build new blood supply to the area have been found along with an increased number of type I collagen fibers. Type I collagen makes up the base structure of tendon tissue. Some studies have shown increased strength of the new tissue while others show no difference in tendon strength between those who got the PRP treatment and those who didn't.
There is no clear direction on when, how, or why PRP should be used. In this experimental phase, surgeons have used it for patients who failed conservative (nonoperative) care for chronic tennis elbow and chronic patellar tendinosis (knee tendon damage). There was one study where it was used for acute (recent) muscle injuries in professional athletes. The results of that study really made the rounds: these high-level athletes recovered in half the expected time and with no bad side effects and no scar tissue or adhesions.
Similar findings have been observed when PRP was used during surgery to repair ruptured Achilles tendons and rotator cuff tears in a small number of patients participating in a pilot study. Once again, wound healing was much faster with fewer problems and less scar tissue. And the list of improvements with this treatment continues: patients use less pain medication, patients gain greater joint motion over a shorter period of time, patients get back to regular daily activities with greater speed and ease, and so on.
A larger study of more than 100 patients using PRP for anterior cruciate ligament (ACL) reconstruction didn't find that the use of PRP enhanced tendon graft healing despite early signs that the maturation process was faster at first. Six months later, MRIs showed no significant effects of this treatment.
Despite these early results, there are more questions than answers about platelet-rich plasma treatment of musculoskeletal problems. But you can expect to see an increase in studies reporting results over the next months to years. Right now, there are clinical trials being carried out in a number of places with a wide range of conditions. While that's being sorted out, Physical Therapists are turning their attention to the proper rehab protocol to follow for these patients. Developing optimal tendon healing and muscle strength, especially in high-level professional athletes who are eager to get back into the game will be a priority.
Reference: Michael P. Hall, MD, et al. Platelet-rich Plasma: Current Concepts and Application in Sports Medicine. In Journal of the American Academy of Orthopaedic Surgeons. October 2009. Vol. 17. No. 10. Pp. 602-608.
