To have a trocar held in the fixed position in the body wall at the time of inserting and removing the trocar into and from the sleeve of an appliance under operation by providing the trocar with a stepped area between an operator side end and a terminal and determining the separate steps by step floors of a circumferential direction and step supporting bases tapered inward in a radial direction.
The trocar 10 has a plug assembly 11 and a trocar cannula 12. The stepped area 19 is integrally formed at the rubber sleeve of the trocar cannula 12 in order to facilitate the holding of the trocar cannula 12 in the abdominal wall under endoscopic treatment. The stepped area 19 has the plural discrete steps in order to impart holding of the trocar cannula 12 in the abdominal cavity. The discrete steps respectively have the step floors of the circumferential direction extending outward in the radial direction from the cannula sleeve and the step supporting bases in the circumferential direction supporting the step floors. The supporting bases extend inward in the radial direction toward the terminal to the adjacent step floors from the step floors and are thus tapered.
GUTIERREZ JORGE N
BLACK CHARLES S
SMITH RICHARD C
