Device and method as disclosed are suitable for fixating soft tissue to hard tissue with the aid of a suture anchor (2) and a suture (4) or with the aid of a headed anchor, wherein the anchor (2) is forced into the hard tissue (forcing step) and then anchored therein (anchoring step) by in situ liquefaction of a material having thermoplastic properties. The device comprises a vibration tool (1) and the anchor (2) and possibly a support element (80), wherein the anchor (2) comprises an anchor foot (22) and a thermoplastic sleeve (23). The thermoplastic sleeve (23) comprises the material having thermoplastic properties. The anchor foot (22) has a distal end suitable for being forced into hard tissue and it is connected to the distal end of the vibration tool (1) and the thermoplastic sleeve (23) sits on a proximal face of the anchor foot (22), the vibration tool and/or a proximal portion of the anchor foot extending into or through the thermoplastic sleeve. The connection between the tool (1) and the anchor foot (22) is equipped for not only transmitting vibration from the tool to the anchor foot but also for transmitting a compressive and a tensile force. Through this measure the anchor (2) can be forced into the hard tissue by applying the compressive force and vibration to the tool (1) and can be anchored in the hard tissue by liquefaction of the sleeve material by applying the tensile force and vibration to the tool (1), i.e. the two steps of the fixation process is carried out using the same tool and without displacing the tool between the two steps.Linvention concerne un dispositif et un procédé pour fixer des tissus mous à des tissus durs à laide dun élément dancrage de suture (2) et dune suture (4) ou à laide dun élément dancrage à tête, lélément dancrage (2) étant forcé dans les tissus durs (étape de forçage) puis ancré dans ceux-ci (étape dancrage) par liquéfaction in situ dun matériau ayant des propriétés thermoplastiques. Le dispositif comporte un outil vi
