EE AND COWORKER WERE INSTALLING 65 LB WEAR LINERS IN A UNIVERSAL IMPACTOR. EE TWISTED BODY WITH THE LOAD FOR PLACEMENT. DURING TWISTING MOVEMENT, HE EXPERIENCED PULL TO LOW BACK. INCIDENT REPORTED TO SUPERVISOR ON MONDAY, 4-8-02. AFTER DISCUSSION, THEY ELECTED TO RECEIVE TREATMENT FROM CHIROPRACTOR.