EMPLOYEE STEPPED ONTO AN OUTRIGGER OF A CRANE, HIS LEFT FOOT SLIPPED AND HE FELL APPROX. 4' TO THE GROUND. EMPLOYEE LANDED ON HIS BACK, HE COMPLAINED OF PAIN TO LOWER BACK, AND RIGHT WRIST. EM PLOYEE SENT TO ARH FOR EXAM, X-RAYS NEG. FOR ANY FRACTURES, EMPLOYEE MISSED 4 DAYS OF WORK.