An employee was responding to a trouble call work order at the home of a customer. He was standing on and working from an extension ladder at an estimated working surface height of 15 ft. in order to remove and replace the drop (aerial cable) that was serving the customer's home. He cut the drop at the point where it was attached to the mid-span. The release of tension on the drop caused the mid-span to recoil, thereby throwing the employee from the ladder to the ground onto his right hip. He sustained a fracture to the lower portion of his back (spine) and was hospitalized.