Doctors used platelet-rich plasma therapy on a partially torn ligament in the throwing elbow of Takashi Saito, a pitcher.

By ALAN SCHWARZ


Professional athletes in football, soccer and baseball have used their own blood in an innovative treatment to heal injured tendons, muscles and ligaments. And hundreds of recreational athletes have also undergone the procedure, commonly called platelet-rich plasma therapy.

Experts in sports medicine say that if the technique¡¯s early promise is fulfilled, it could eventually improve the treatment of stubborn injuries like tennis elbow and knee tendinitis for athletes of all types.

The method, which is strikingly straightforward and easy to perform, centers on injecting portions of a patient¡¯s blood directly into the injured area, which catalyzes the body¡¯s instincts to repair muscle, bone and other tissue. Most enticing, many doctors said, is that the technique appears to help regenerate ligament and tendon fibers, which could shorten rehabilitation time and possibly obviate surgery.

Research into the effects of plateletrich plasma therapy has accelerated in recent months, with most doctors cautioning that more rigorous studies are necessary before the therapy can emerge as scientifically proven. But many researchers suspect that the procedure could become an increasingly attractive course of treatment for reasons medical and financial.

¡°It¡¯s a better option for problems that don¡¯t have a great solution - it¡¯s nonsurgical and uses the body¡¯s own cells to help it heal,¡±said Dr.Allan Mishra, an assistant professor of orthopedics at Stanford University Medical Center in Palo Alto, California, and one of the primary researchers in the field.¡°I think it¡¯s fair to say that platelet-rich plasma has the potential to revolutionize not just sports medicine but all of orthopedics. It needs a lot more study, but we are obligated to pursue this.¡±

Dr.Neal ElAttrache, the team physician for the Los Angeles Dodgers baseball team, used platelet-rich plasma therapy in July on a partially torn ulnar collateral ligament in the throwing elbow of Takashi Saito, a pitcher. Surgery would have ended Mr.Saito¡¯s season and put him out of action for about 10 to 14 months; he instead returned to pitch before the season ended in September without pain.

Dr.ElAttrache said he could not be certain that the procedure caused the pitcher¡¯s recovery - about 25 percent of such cases heal on their own, he said - but it was another encouraging sign for the nascent technique.

Platelet-rich plasma is derived by placing a small amount of the patient¡¯s blood in a filtration system or centrifuge that rotates at high speed, separating red blood cells from the platelets that release proteins and other particles involved in the body¡¯s self-healing process, doctors said. A teaspoon or two of the remaining substance is then injected into the damaged area.

The high concentration of platelets - from 3 to 10 times that of normal blood - often catalyzes the growth of new soft-tissue or bone cells. Because the substance is injected where blood would rarely go otherwise, it can deliver the healing instincts of platelets without triggering the clotting response for which platelets are typically known.

¡°This could be a method to stimulate wound healing in areas that are not well-vascularized, like ligaments and tendons,¡±said Dr.Gerjo van Osch, a researcher in the department of orthopedics at Erasmus University Medical Center in the Netherlands.¡°I call it a growth-factor cocktail - that¡¯s how I explain it.¡±

Dr.van Osch and several other experts said they had used the procedure as a first option before surgery for reasons beyond its early results. There is little chance for rejection or allergic reaction because the substance is autologous, meaning it comes from the patient¡¯s own body; the injection carries far less chance for infection than an incision and leaves no scar, and it takes only about 20 minutes, with a considerably shorter recovery time than after surgery.

Because of those apparent benefits, the consensus among doctors is that the procedure is worth pursuing. However, several doctors emphasized that platelet-rich plasma therapy as it stands now appeared ineffective in about 20 to 40 percent of cases, depending on the injury.

Dr.Mishra said that he was particularly encouraged by PRP therapy¡¯s effectiveness on chronic elbow tendinitis, or tennis elbow.

¡°The guy who plays softball on weekends, the woman who runs a 5K race every now and then, they suffer very common injuries,¡±said Samir Mehta, the chief of the orthopedic trauma service at the Hospital of the University of Pennsylvania, who has performed PRP therapy on nine patients.¡°It¡¯s for those people that we hope that this therapy¡¯s uses can be more apparent.¡±