EE WAS PICKING UP A 6"" X 6"" TIMBERS TO BE SET ON 2ND NORTH PANEL BELT, WHEN WHILE LIFTING THE TIMBER HE FELT HIS RIGHT SHOULDER POP. EE STATED HE THOUGHT HIS SHOULDER POPPED BACK INTO PLACE & CONTINUED TO WORK THE REMAINDER OF HIS SHIFT & FOR THE NEXT 2 WEEKS HE WAS STILL EXPERIENCING SOME PAIN IN HIS SHOULDER.