A vibration transmitter can include a straight portion, a curved portion, a first curved surface provided on an external surface of the curved portion, a second curved surface facing a side opposite to the first curved surface and a first portion provided on the first curved surface. The first portion can extend towards a side opposite to the side toward which the curved portion is curved and a distance between the first portion and an imaginary curved surface can increase from the proximal side toward the distal side, and the imaginary curved surface being parallel with the second curved surface.