PROBLEM TO BE SOLVED: To provide not only a medical treatment instrument easily reduced in diameter but also a manipulator easy to reduce the diameter of the part where manipulation is performed in the body cavity.SOLUTION: The medical treatment instrument 1 includes a treatment part 10 having first and second forceps pieces 11 and 12 mutually connected in a relatively revolvable manner by a forceps revolving shaft 13, an operation member 20 having flexibility at least at a part thereof and connected to the base end part of the treatment part at the leading end part thereof and a sheath part 30 which has flexibility and in which the operation member is inserted so as to advance and retreat longitudinally. The operation member is formed into a hard part 20A having higher rigidity than another region over a predetermined length range from the leading end thereof and the connection region with the treatment part and the operation member is set so as to be positioned on the outside of the sheath part in a state that the operation member is allowed to most retreat and the length of the hard part is set so that another region is not exposed to the outside of the sheath part in the state that the operation member is most advanced.COPYRIGHT: (C)2012,JPO&INPIT【課題】小径化が容易な医療用処置具を提供する。【解決手段】医療用処置具1は、鉗子回動軸13で互いに相対回動可能に連結された第一鉗子片11および第二鉗子片12を有する処置部10と、少なくとも一部が可撓性を有し、処置部の基端部に自身の先端部が接続された操作部材20と、可撓性を有し、操作部材が長手方向に進退可能に挿通されたシース部30とを備え、操作部材は、先端から所定の長さの範囲が他の部位よりも高い剛性を有する硬質部20Aとされており、処置部と操作部材との接続部位は、操作部材が最も後退された状態においてシース部の外に位置するように設定され、硬質部の長さは、操作部材が最も前進された状態において他の部位がシース部の外に露出しないように設定されていることを特徴とする。【選択図】図3
