In accordance with an aspect of the invention, a medical device is provided, the device for example being implantable into a human or animal body or being an augmentation device for strengthening human or animal hard tissue for subsequent implantation of a separate implant. The device comprises a sheath element suitable of being brought into contact, during a surgical operation, with live hard tissue and/or with hard tissue replacement material, the sheath element having a longitudinal bore defining a longitudinal opening reaching from a proximal end of the sheath element into a distal direction, and a plurality of holes in a wall of the opening. It further comprises a liquefiable element that is insertable or inserted in the longitudinal opening and at least partly liquefiable by the impact of energy impinging from the proximal side so that liquefied material flows through the holes in the wall and out of the longitudinal opening into structures of the hard tissue and/or hard tissue replacement material. Further, the device comprises:- A first distal stop face against which a distal end of the liquefiable element is pressable for liquefaction, the first distal stop face being at a first position, and- An insert element (18) comprising a second distal stop face, the insert element insertable from a proximal side into the longitudinal opening and shaped to be stop at a position in which the second distal stop face is at a second position different from the first position.
