An implant deployment device (10) includes a pusher member (30), inner catheter (24), dilator tip (20) upon which an implant (18) is supported during deployment into a lumen of a patient. A sheath (32) substantially surrounds the pusher member (30), the inner catheter (24), the dilator tip (20), covering the implant (18) and containing the implant (18) therewithin. The pusher member (30), inner catheter (24), dilator tip (20) has at least one longitudinal groove formed in its outer surface. This engages with at least one tooth (112) formed in an inner surface of the sheath (32) or an inner surface of a component of the device that is attached to the sheath (32), such as a clamping collar (90) or a locking unit (100). The tooth (112) engages with a longitudinal groove (80) and is able to move along the groove (80) in a longitudinal direction. The engagement of the tooth (112) within the groove (80), however, prevents relative rotation between the sheath (32) and the pusher member (30), inner catheter (24), dilator tip (20). Twisting of an implant (18) supported on the inner catheter (24) is thus avoided.
