Method of fastening a tissue or a corresponding prosthetic element in an opening provided in a human or animal bone and fastener suitable for the method

A method for fastening tissue or a corresponding prosthetic element in an opening in a human or animal bone comprising the steps of:

• providing a fastener and at least one anchoring element comprising a liquefiable material, wherein the fastener comprises at least one groove which extends from a proximal fastener face towards a distal fastener end;
• providing the opening in the human or animal bone, the opening comprising at least one mouth in a bone surface and an inside wall and being dimensioned for the fastener to fit into the opening;
• press-fitting the tissue or prosthetic element in the opening by positioning the tissue or prosthetic element in the opening and pressing the tissue or prosthetic element against a first wall portion of the inside wall by forcing the fastener into the opening or by expanding the fastener in the opening;
• pushing the at least one anchoring element into the groove of the fastener;
• liquefying at least part of the liquefiable material in a vicinity an immediate vicinity of and in contact with a second wall portion different from the first wall portion of the inside wall and making the liquefiable material contact said second wall portion by simultaneously transmitting energy to the liquefiable material of the anchoring element and advancing the anchoring element relative to the fastener;
• and
• letting the liquefied material re-solidify in contact with the second wall portion.