EMPLOYEE WAS ROLLING A LARGE BLOCK OF WOOD END OVER END. EMPLOYEE SAID HIS SHOULDER POPPED OUT AND BACK INTO PLACE. HE WENT TO THE CLINIC 4/18;THE DOCTOR DIAGNOSED A STRAINED SHOULDER. NO X- RAYS WERE TAKEN. EMPLOYEE SAID IT HAD GOTTEN WORSE. HE WENT BACK ON 8/16. THE DOCTOR NOW THINKS HE HAS A ROTATOR CUFF TEAR. A MRI IS SCHEDULED. NO MODIFIED DUTY WAS REQUESTED.