Employee notified of fault on conveyor, utilized LOTO, opened gates to return rollers. While opening gate, it struck left wrist. Did not break skin or swell. Ice provided, he continued to work. Saw doctor 9/4/09, original diagnosis was sprain. Employee returned to work 9/4/09. Follow up appointments for pain in Nov, Dec. MRI on 1/22/10 revealed tear. Surgery on 2/1/2010.