"The procedure that Alex Rodriguez had performed on his ailing right knee and left shoulder in Germany between Dec. 5-9 is called Orthokine therapy, which involves a healing activator used in the popular blood-spinning treatments known as platelet-rich plasma therapy or PRP. But while PRP is approved for use in the U.S., Orthokine therapy is not believed to be approved in either this country or Canada.

After A-Rod got a recommendation from Lakers star Kobe Bryant to get the Orthokine therapy, Major League Baseball and the Yankees gave the green light for the $275 million Yankee star to travel to Germany for the treatment, Yankee general manager Brian Cashman said on a conference call Wednesday. The treatment is not banned by the World Anti-Doping Agency (WADA) or Major League Baseball, but Cashman's claim that Orthokine therapy is performed in the U.S. was disputed by several medical professionals, including Dr. Lewis Maharam, a past president of the New York chapter of the American College of Sports Medicine and a proponent of the use of PRP."