Sacral Neuromodulation (SNM) With InterStimTM for Bowel Dysfunction Following Surgery for Rectal Cancers With Sphincter Preservation

The purpose of this study is to evaluate whether a medical device/implant (InterStimTM) will help patients to have more normal bowel movements. The InterStimTM device is a neuromodulating device. Neuromodulation is a way of changing the activity of the nervous system by using electrical stimulation. InterStimTM is FDA approved to help people who have a hard time controlling their bowl movements. This is called fecal incontinence.The device is placed near a nerve root in the lower back. It works in a manner similar to a pacemaker by releasing electrical stimulation that triggers the S3 nerve root. When being placed, it is initially tested to make sure it will work using a temporary wire and then, if successful, the device is permanently implanted.