U.S. Defense Secretary Donald Rumsfeld underwent elective surgery to repair a shoulder injury described as "an old athletic injury" at a military hospital on Tuesday, the Pentagon said, according to Reuters. Rumsfeld, 74, underwent surgery lasting less than two hours to fix a torn rotator cuff, a relatively common sports injury, said Pentagon press secretary Eric Ruff. Ruff said Rumsfeld might be kept overnight at Walter Reed Army Medical Center in Washington.