EE WAS ATTEMPTING TO REPOSITION THE TRAILING CABLE WITH AN INSULATED CABLE HOOK. THE CABLE WAS DAMP AND AS HE STARTED TO PULL ON THE HANDLE, THE HOOK SLID ALONG THE CABLE. HE LOST HIS BALANCE AND FELL BACKWARDS STRIKING THE BACK OF HIS HEAD ON THE D-RING OF THE CABLE TRACTOR PARKED NEARBY. THE BLOW CAUSED A LACERATION WHICH REQUIRED 9 STITCHES TO CLOSE.