Your urinary sphincter is the muscle that controls urine flow from your bladder. An artificial urinary sphincter (AUS) is a device that takes over the work of a non-functioning urinary sphincter. This ...

The esophageal sphincters are bands of muscles at the top and bottom of the esophagus — the muscular tube that passes food and drink from the mouth to the stomach. Esophageal sphincters open and close ...