An impactor (100) for transferring an impaction force to a prosthesis (4) coupled to a prepared distal end of a bone (6). The impactor (100) comprises a connector (154) arranged to couple to a prosthesis (4) and an impactor handle (134). The impactor handle (134) defines an impaction axis (110) extending into the prosthesis (4) such that an impaction force applied to the impactor handle (134) is transferred to the prosthesis (4) along the impaction axis (110). When the connector (154) is coupled to a prosthesis (4) the point at which the impaction axis (110) extends into the prosthesis (4) is spaced apart from the coupling between the connector (154) and the prosthesis (4).
