HIP JOINT ENDOPROSTHESIS Russian patent published in 2007 - IPC A61F2/36 

FIELD: medical engineering.

SUBSTANCE: device has head, neck member, pedicle and recess. The recess has two hemispherical cups concentrically arranged with free space between them to allow approaching each other and moving aside. Damping members are mounted between the cups in their radial recesses. Flexible ring-shaped washers are available between external cup end face and flange of the internal one and also between internal cup end face and external fastening ring. The internal cup is coupled with the external one by means of guide members available in its flange holes and fixed in the external cup end face. Cylindrical holes are available on mating surfaces of both cups in front of each other. The internal cup has dead holes and the external one has through holes. Dead holes diameters correspond to lower part diameters of the through holes. Damping members being spiral-shaped compression springs are mounted in the holes with diametrical free spaces left. Thrust thread is cut on middle portions of the through holes matching thread in lower stub parts. Stub end faces are used as supporting platforms for springs. Upper parts of the stubs have cylindrical shape with smooth walls and serve as the proper stubs of the through holes while matching their upper part shape and diameters. Splint members are mounted on pyramid-shaped ends of each stub, their sharp ends projecting above the external cup surface.

EFFECT: enhanced damping effectiveness under action of sign-variable loadings applied in different directions.

4 dwg