INJURED WAS ASSIGNED TO INSTALL SIGNS & METAL POSTS USING A 20 LB SLEDGE HAMMER TO DRIVE IN METAL POSTS INTO THE GROUND. DURING THIS PROCESS THE INJURED MISSED THE POST AND STRUCK HIS LEFT HAN D ON TOP EDGE OF SIGN POST. THE INJURED WAS HOLDING THE HANDLE TOO CLOSE TO THE HEAD OF THE HAMMER RESULTING IN A CUT TO BACK OF HAND BETWEEN INDEX FINGER AND THUMB AREA. 14 STITCHES