ELBOW JOINT ENDOPROSTHESIS OF CEMENT-FREE FIXATION Russian patent published in 2017 - IPC A61F2/38 

FIELD: medicine.

SUBSTANCE: invention relates to medicine. Elbow joint endoprosthesis of cement-free fixation contains elbow component, shoulder component and lock screw. Shoulder component is made in form of rod for bone marrow canal, with rounded narrowing on one free end, and receiving unit on the other, adjacent end. Rod is made with bends, which imitate anatomical profile of bone marrow canal of shoulder bone, stepped in length, with smooth transitions, rectangular in transverse section, decreasing towards rounded narrowing. On at least two opposite sides of rod transverse prongs, sharp ends of which are directed towards adjacent end, are made. Receiving unit is made in form of rod thickening, which has on-bone base with fixing tongue on the edge, which lies on front surface of shoulder bone, and opposite to on-bone base, which has inclined area, inclination of which goes towards tongue. In medium part of inclined area, perpendicularly to is plane, made is elongated deepening, longitudinal walls of which are transverse relative to area inclination, on one of longitudinal sides, along and inside deepening, made rib-guide is made. From the side, opposite to tongue, in thickening, on curved lateral surface, adjoining the top of inclined area, thread hole for lock screw is made perpendicularly to deepening. Elbow component has nail for bone marrow canal and articulate unit. Nail is made with bends, which imitate bends of bone marrow canal of elbow bone, from one side with rounded narrowing, which starts from nail medium, and from the other side and from other side, starting from medium, in successively located areas with transverse prongs, sharp ends of which are directed from rounded narrowing, then on-bone steps and deflected fixing end. Nail is made rectangular in transverse section, which decreases towards rounded narrowing Articulate unit has body and spherical head on leg, with the latter being fastened on butt end of deflected fixing end of nail. Body is made cylindrical, spherical on one end, and on other - with elongated projection for placement in elongated deepening of receiving unit of shoulder component. Body also has cavity for spherical head and connected with this cavity slot for leg, which is located on spherical end of body with transition on cylindrical part. In body there is a stop to provide limitation of spherical head travel. Elongated projection is made with bevel on butt end and transverse blind thread-free channel for lock screw and groove for rib-guide. Channel axes, grooves and slots are located in one plane, which passes on longitudinal axis of body, with elongated projection being located across this plane. Lock screw has chamfer on one end, and butt end deepening for key on other end, from the side of chamfer made smooth for thread-free blind channel in elongated projection of elbow component, and from the side of deepening - threaded for screwing into threaded opening, with a stop on threaded part of lock screw.

EFFECT: invention ensures reduction of operation access trauma (without exposure of elbow nerve, without transection or sub-periosteal exposure of triceps brachii muscle), which contributes to reduction of operation time and reduction of rehabilitation period.

4 cl, 4 dwg