Medical treatment tool

A medical treatment tool comprising:

• a forceps that treats an affected area;
• an operating section comprising a handle and a dial, and configured to operate the forceps;
• a guide sheath arranged between the forceps and the operating section;
• a first bending section and a second bending section arranged between the operating section and the forceps in a manner spaced apart from each other in a longitudinal direction, the first bending section and the second bending section bending the guide sheath;
• at least two treatment tool wires that pass through the first bending section and the second bending section of the guide sheath and that transmit, to the forceps, a force applied to the operating section;
• a bending sheath that allows the guide sheath to pass therethrough;
• and
• at least two bending wires that pass through the bending sheath and that are fixed to a distal end and a proximal end of bending sheath, the bending wires causing the guide sheath to be bent by operating the operating section,
• wherein the bending sheath is bent by bending the second bending section by operating the operating section, and the first bending section is bent according to bending of the bending sheath,
• the guide sheath comprises a multi-lumen tube with a plurality of lumens that allow the treatment tool wires to pass therethrough,
• the forceps and the guide sheath are arranged so as to be movable back and forth in the longitudinal direction relative to the bending sheath,
• twist of the lumens of the guide sheath is arranged to be kept between the first bending section and the second bending section, and
• the first bending section and the second bending section are bent in directions in which changes in path lengths of the treatment tool wires in the guide sheath caused by bending of the first bending section are offset by changes in the path lengths of the treatment tool wires in the guide sheath caused by bending of the second bending section.