EMPLOYEE WAS USING A 24 INCH PIPE WRENCH TO FREEA STUCK SHAFT. WRENCH SLIPPED THEN CAUGHT AGAIN. HIS HAND WAS BETWEEN THE PIPE WRENCH & HIS BODY & HE HEARD SOMETHING SNAP. HE WORKED THE NEXT 2 DAYS THEN DECIDED TO TELL HIS SUPERVISOR & WAS SENT FOR X-RAYS. IT WAS FOUND HE BROKE A BONE ABOVE HIS LEFT HAND LITTLE FINGER.