Patent ID: 8114140

Claim:
Implantable orthopedic device comprising: a support structure ( 2 ) delimited by an upper face ( 2 ′) and a lower face ( 2 ″), said lower face adapted to rest against a receiving bone material, said support structure ( 2 ) being provided with at least one housing ( 5 ) and at least one orifice ( 3 ) passing through said housing ( 5 ), said housing ( 5 ) and said orifice ( 3 ) having the same axis ( 5 ′), at least one nut ( 6 ) provided with an internal thread ( 14 ), said nut ( 6 ) being shaped so as to be caught within one of said housings ( 5 ), and at least one fixing screw ( 4 ) consisting of a screw head ( 15 ) and a screw body ( 16 ), said screw head ( 15 ) being provided with a thread ( 17 ) configured to cooperate with said nut thread ( 14 ), and said screw body ( 16 ) being provided with a thread ( 18 ) configured to cooperate with the receiving bone material, said nut ( 6 ) being locked against rotation within said receiving housing ( 5 ) so as to prevent said nut from rotating around its axis ( 6 ′), and said nut ( 6 ) having at least one degree of freedom within said receiving housing ( 5 ), according to a predetermined acceptable tilting domain, so as to enable a tilting of its axis ( 6 ′) relative to the axis ( 5 ′) of said receiving housing ( 5 ), said fixing screw ( 4 ) being intended to be screwed within one of said orifices ( 3 ) and the associated nut ( 6 ) thereof, according to a selected angle in the acceptable tilting domain, said housing ( 5 ) further comprising an upper part ( 5 a ) located on the upper face ( 2 ′) side of the support structure ( 2 ) and a lower part ( 5 b ) located on the lower face ( 2 ″) side of said support structure ( 2 ), both parts being generally truncated sphere shaped and concentric to each other, and said nut ( 6 ) having a truncated sphere shaped peripheral contour ( 11 ) mating with said truncated sphere shaped upper part ( 5 a ) of the receiving housing ( 5 ), said screw head ( 15 ) having an upper part ( 15 a ) provided with said thread ( 17 ) and a lower part ( 15 b ) whose contour has a generally truncated sphere shape mating with said truncated sphere shaped lower part ( 5 b ) of the receiving housing ( 5 ), said upper ( 15 a ) and lower ( 15 b ) parts of said screw head ( 15 ) configured to cooperate, during the final screwing step of said screw ( 4 ), with the thread ( 14 ) of said nut ( 6 ) through the mating thread ( 17 ) thereof and with said lower part ( 5 b ) of the receiving housing ( 5 ), respectively, so as to tend to separate said nut ( 6 ) from said lower part ( 5 b ) of the receiving housing ( 5 ), and then impart a forced rest of the peripheral contour ( 11 ) of said nut ( 6 ) against said mating upper part ( 5 a ) of the receiving housing ( 5 ) and a forced rest of the lower part ( 15 b ) of said screw head ( 15 ) against said mating lower part ( 5 b ) of the receiving housing ( 5 ), in order to obtain the locking of said screw ( 4 ) during the final screwing step.