EE WAS USING A 20# SLEDGEHAMMER & KNOCKER WRENCH TO TIGHTEN JAW BOLTS; THE HAMMER WAS DEFLECTED CAUSING IT TO MISS THE WRENCH STRIKING FINGER CAUSING A FRACTURE & LACERATION TO L-INDEX FINGER. EE WENT TO SEE COMPANY DR ON 3/13/02 & WAS PLACED ON RESTRICTED DUTY.