An employee was repairing a damaged load cover on a triaxle dump truck in which the right side of the load cover assembly was not raising up. The employee manually pushed up on the cylinder arm of the assembly, but the roller bar was stuck against two screws at the top of the tailgate. While standing on an 8-foot step ladder, the employee released the roller bar, causing it to rapidly spin due to spring tension inside the bar. The roller bar struck the employee's hand, crushing and lacerating his right index, middle, and ring fingers.