Intramedullar osteosynthetic device of two bone parts, in particular of the hand and/or foot

An intramedullary implant device for implantation between a pair of adjacent bone parts, the device being unitarily formed of flat cross section, the implant comprising:

• a central part having longitudinally opposite ends;
• a first fixation zone having a respective pair of first tabs projecting longitudinally away from one of the ends, the first tabs being displaceable between an outer position in which they are widely spaced and diverge from each other away from the central part and an inner position in which they are closely spaced, wherein the tabs of the first fixation zone are constructed of a shape-memory material and the tabs of the first fixation zone assume the outer position at body temperature through shape-memory action;
• and
• a second fixation zone projecting outward and away from the other end and having a second pair of tabs constructed of a shape-memory material and having outer ends that are joined unitarily together such that they form a throughgoing planar slot permitting transverse expansion by shape-memory action at body temperature.

An intramedullary implant for use between a pair of adjacent bone parts, the implant extending along an axis and being unitarily formed, the implant comprising:

• a generally triangular median zone having axially opposite ends one of which forms an outer face extending generally perpendicular to the axis to form an abutment having a width, the abutment being adapted to be positioned against a surface of one of the bone parts;
• two fixation zones made from a shape-memory material;
• each one of the fixation zones having a respective pair of tabs projecting longitudinally outward, each pair of tabs being displaceable between an outer position in which they are widely spaced and diverge from each other axially away from the median zone and an inner position in which they are closely spaced, wherein the pairs of tabs assume the outer position by shape-memory action at body temperature;
• and
• a connecting zone between the median zone and a fixation zone and extending over a predetermined length, wherein the connecting zone has a width that is less than the width of the abutment.