After running approximately 1,600 feet of 8-5/8 inch casing a floorhand climbed onto the top of the casing and cementing head to make up a chicksan joint. After completing the task, the employee decided to remove the pick-up line from the joint while he was there. During this time, the Driller engaged the rig pump to break circulation and wash the casing to bottom. As a result, the casing began to push out of the hole and slid up through the elevators pinning the employee’s right leg and
knee between the cementing head and blocks. The employee sustained injuries to his knee and lower leg.