This procedure is used to treat lower back pain and leg pain. Initially a trial will be scheduled to test the effectiveness of spinal cord stimulation before implanting the device. During the procedure a pacemaker-sized stimulator device is surgically implanted under the skin. It electrically activates a pain-inhibiting process and causes a tingling sensaton that masks pain. The stimulator sends pulsed elecrical signals to the spinal cord to control chronic pain. If the trial is successful then a permanent implant will be scheduled.