At 37, New York Yankees pitcher Bartolo Colon looked like he was at the end of his 13-year Major League Baseball career. After damaging his rotator cuff and a ligament in his arm—the sort of injury that frequently ends a player's career—he underwent complex surgery in April 2010.
The surgery gave Colon's career a boost. His fastball speed returned, clocking in at 93 miles per hour, and the Yankees put Colon into their starting rotation. Yet the renewed success has come at a price. Colon is being investigated by Major League Baseball for using a surgical treatment involving stem cells. Baseball authorities are inquiring into whether this qualifies as an "enhancement," which would violate league rules.
Colon's treatment was overseen by Joseph Purita, the founder of the Institute of Regenerative and Molecular Orthopedics in Boca Raton, Florida. Purita injected stem cells extracted from Bartolo's own fat and bone marrow into the affected arm. Although the treatment is medically unproven among human beings, peer-reviewed studies suggest that it works well in horses, and Purita told The New York Times he has successfully treated at least 24 professional athletes during the last two years.