An improved surgical instrument having an end effector mounted on the end of an elongate shaft extending from a handle is described, the shaft and hence end effector being rotatable with respect to the housing, to allow different rotational orientations of the end effector to be attained without having to rotate the whole instrument. In order to provide for control over the degree of rotation of the shaft with respect to the handle, for example to prevent excess strain on any internal wiring due to excessive rotation in the same direction, shaft rotation control elements are provided to give rotation or torsion control over the shaft. The shaftrotation control elements may be located at one of, or plural of, several different longitudinal positions along the shaft. For example, shaft rotation control elements in the form of respectively co-operating stops may be provided on or about a thumbwheel at the proximal end of the housing to the user, the thumbwheel being used to rotate the elongate shaft. Alternatively, rotation control elements in the form of mutually co-operating stops may be provided elsewhere, such as for example, in a rotatable shaft support member provided at the distal end of the handle from the user, and which is provided nominally to support the shaft in transition from positions in the interior of the handle to the exterior of the handle along the length of the shaft. In other embodiments rotation control stops are provided on both elements, thus providing for very effective rotation control, which has a very positive and high quality feel to the user. <；Figure 15a>；
