Abstract: The fusion device for fusing a synovial joint of a human or animal patient, in particular a human facet joint, finger joint or toe joint, includes two pin-shaped anchorage portions and arranged therebetween a stabilization portion. The anchorage portions include a thermoplastic material which is liquefiable by mechanical vibration. The stabilization portion preferably has a surface which is equipped for enhancing osseointegration. The anchorage portions have a greater thickness and a greater depth than the stabilization portion. Then the fusion device is pushed between the articular surfaces and mechanical vibration, in particular ultrasonic vibration, is applied to the proximal face of the fusion device. Thereby the liquefiable material is liquefied where in contact with the bone tissue and penetrates into the bone tissue, where after re-solidification it constitutes a positive fit connection between the fusion device and the bone tissue.

Abstract: The fusion device for fusing a synovial joint of a human or animal patient, in particular a human facet joint, finger joint or toe joint, includes two pin-shaped anchorage portions and arranged therebetween a stabilization portion. The anchorage portions include a thermoplastic material which is liquefiable by mechanical vibration. The stabilization portion preferably has a surface which is equipped for enhancing osseointegration. The anchorage portions have a greater thickness and a greater depth than the stabilization portion. Then the fusion device is pushed between the articular surfaces and mechanical vibration, in particular ultrasonic vibration, is applied to the proximal face of the fusion device. Thereby the liquefiable material is liquefied where in contact with the bone tissue and penetrates into the bone tissue, where after re-solidification it constitutes a positive fit connection between the fusion device and the bone tissue.

Abstract: The fusion device for fusing a synovial joint of a human or animal patient, in particular a human facet joint, finger joint or toe joint, includes two pin-shaped anchorage portions (1) and arranged therebetween a stabilization portion (2). The anchorage portions (1) include a thermoplastic material which is liquefiable by mechanical vibration. The stabilization portion (2) preferably has a surface which is equipped for enhancing osseointegration. The anchorage portions (1) have a greater thickness (T1) and a greater depth (D) than the stabilization portion (2). Then the fusion device is pushed between the articular surfaces and mechanical vibration, in particular ultrasonic vibration, is applied to the proximal face (4) of the fusion device. Thereby the liquefiable material is liquefied where in contact with the bone tissue and penetrates into the bone tissue, where after re-solidification it constitutes a positive fit connection between the fusion device and the bone tissue.

Abstract: A method of anchoring an implant in hard tissue, and/or hard tissue replacement material, includes the steps of providing an initial opening in the hard tissue, providing a thermoplastic augmentation element, a tool and a counter element, compressing the augmentation element between the tool and the counter element while energy is coupled into the tool and while a periphery of a liquefaction interface of the tool and the augmentation element and/or of a liquefaction interface of the augmentation element and the counter element is in the opening, thereby liquefying material of the augmentation element at the liquefaction interface(s) to yield liquefied material, causing portions of the liquefied material to penetrate into structures of the hard tissue, allowing the liquefied material to harden and to thereby become augmentation material, removing the tool and the counter element, and anchoring the implant in the opening including at least some of the augmentation material.