EMPLOYEE WAS OPERATING T37 HOT CHANGE VEHICLE AT S29. THE SHOVEL OPERATOR BLEW THE HORN CAUSING EE TO SPIKE THE BRAKES. WHEN SHE DID THIS, SHE HIT HER ELBOW ON THE BOTTOM OF THE STEERING WHEEL . SHE WAS EVALUATED BY A PHYSICIAN AND PHYSICAL THERAPY STARTED ON 10-16-01.