ASSEMBLY COMPRISING AN IMPLANTABLE PART DESIGNED TO BE FASTENED TO ONE OR MORE BONES OR BONE PORTIONS TO BE JOINED, AND AT LEAST ONE SCREW FOR FASTENING THE IMPLANTABLE PART TO SAID BONE(S)
An assembly including an implantable part designed to be fastened to at least one bone or bone portions to be joined and at least one screw for fastening the implantable part to the at least one bone or bone portions. The implantable part includes at least one tapped hole and the screw includes a head designed to be engaged in the tapped hole. The tapped hole is cylindrical and includes at least one radial notch emerging in a surface of the implantable part through which the screw is designed to be engaged in the tapped hole. The radial notch produces an interruption in the tapping included by the tapped hole. The head of the screw is conical, with an apical angle of between 15 and 25°.
1 . An assembly comprising:
an implantable part designed to be fastened to at least one bone or bone portions to be joined, and
at least one screw for fastening the implantable part to the at least one bone or bone portions, said implantable part includes at least one tapped hole, and said screw includes a head designed to be engaged in said tapped hole;
wherein:
the tapped hole is cylindrical and includes at least one radial notch emerging in a surface of said implantable part through which the screw is designed to be engaged in the tapped hole,;
said radial notch produces an interruption in the tapping comprised by the tapped hole;
the head of the screw is conical, with an apical angle comprised between 15 and 25°, and
the head is threaded and the pitch of the thread includes between one third and one half the pitch of the thread making up the tapping of the tapped hole, and the depth of the thread of the head includes between one half and two thirds of the depth of the pitch of the thread making up the tapping of the tapped hole.
2 . The assembly according to claim 1 , wherein said apical angle is 20°.
3 . The assembly according to claim 1 , wherein the pitch of the thread of the head of the screw is in the vicinity of one half the pitch of the thread of the tapping of the tapped hole.
4 . The assembly according to claim 1 , wherein said screw comprises a body and a bone screw thread extends along that body into the immediate vicinity of said head of said screw, below said head, such that the proximal end of said screw thread is situated, when the screw is in place on the implantable part, inside said tapped hole.
5 . The assembly according to claim 1 , wherein said notch extends over the entire height of said tapped hole.
6 . The assembly according to claim 1 , wherein said tapped hole comprises a plurality of said notches.
7 . The assembly according to claim 6 , wherein said notches are present over the entire circumference of said tapped hole, allowing an angulated orientation of said screw over the entire circumference.
8 . The assembly according to claim 6 , wherein said notches are regularly distributed on that circumference.
9 . The assembly according to claim 6 , wherein said notches are present on a first sector of the circumference of the tapped hole and absent on a second sector of the circumference of said tapped hole.
10 . The assembly according to claim 1 , wherein said implantable part is a fastening base for fastening part of a joint prosthesis to a bone.
11 . The assembly according to claim 10 , wherein said implantable part is a fastening base for fastening a glenoid to shoulder blade in a total shoulder prosthesis.
12 . The assembly according to claim 1 , wherein said implantable part is a cortical plate.
13 . The assembly according to claim 12 , wherein said implantable part is a superior humeral cortical plate.
14 . The assembly according to claim 12 , wherein said implantable part is an inferior radius cortical plate.