Bartolo Colón active players as of June 11, 2008. Colón did not pitch in 2010 due to ongoing right shoulder and elbow pain and damage to the rotator cuff, ligaments and tendons. In March 2010, he received a transplant of stem cells to repair the damaged tissues in his right shoulder. The orthopedic surgeon who performed the surgery said he had used human growth hormone in previous surgeries of the same type but not with Colón. The surgery was scrutinized by MLB but no wrongdoing was found. Colón then played in the Pre-World Championship in Puerto Rico, winter ball with the Aguilas
Giant-cell tumor of the tendon sheath Giant-cell tumor of the tendon sheath Giant-cell tumor of the tendon sheath, also known as giant-cell synovioma and localized nodular tenosynovitis, is a firm lesion, measuring 1 to 3 cm in diameter, and is most commonly attached to the tendons of the fingers, hands, and wrists, with a predilection for the flexor surfaces. Giant-cell tumor of tendon sheaths most often affect the wrist and fingers of males and females from the ages of 20-50 . These tumors are typically painless and can cause cortical erosion. Surgery to remove the tumor is a common treatment, though the tumors tend to recur.