EE WAS SHAKING SILICA BAGS TRYING TO GET ALL THE SILICA OUT WHEN HE FELT A PAIN BETWEEN HIS SHOULDER BLADES. PAIN RADIATED DOWN RIGHT ARM INTO THE FOREARM. HE INITIALLY RECEIVED FIRST AID (ON 8/21/03) TREATMENT UNTIL 9/3/03 WHEN HE WAS PLACED ON LIGHT DUTY & PRESCRIBED PHYSICAL THERAPY.