A Concealed "Natural Orifice": Umbilicus Anatomy for Minimally Invasive Surgery.

With the widespread use of MIS, umbilical incision is commonly used to reduce pain and improve cosmetic results. This study consistently revealed a natural defect of fascia in the center of the umbilicus. Therefore, the umbilicus can be called a concealed "natural orifice." It is important to recognize and utilize this defect effectively to minimize unnecessary tissue trauma during MIS.