EE WAS HAVING THE ROCK TRUCK HE WAS OPERATING LOADED WITH COAL BY A FRONT END LOADER. A ROCK FELL OUT OF THE LOADER BUCKET AND HIT THE ROCK TRUCK, JARRING THE ROCK TRUCK AND EE CONTACTED THE FOREMAN AND INFORMED HIM THAT HIS BACK WAS HURTING AND THE FOREMAN TOOK EE TO E.R. TO HAVE HIS BACK EXAMINED.