BONE FIXATION SYSTEM Russian patent published in 2018 - IPC A61B17/80 A61B17/86 

FIELD: medicine.

SUBSTANCE: group of inventions relates to medicine. Bone fixation system contains a bone implant and a bone fixation element. Bone implant comprises implant body that defines upper surface and a surface facing the bone opposite the upper surface, and hole for fixing the bone that passes through the implant body from the upper surface to the surface facing the bone. Hole for fixing the bone is at least partially formed by a threaded inner wall. Bone implant comprises first and second wire portions, which define respectively the first and second threaded inner walls that face each other so as to form said threaded inner wall. Bone fixation member comprises a head and a stem which extends with respect to the head in the distal direction and is configured to be inserted into the fixation site, wherein the bone fixing member further defines a stop surface and the head forms at least one thread that is spaced from the stop surface in the distal direction. At least one thread is threadably engaged with the threaded inner wall when the bone fixing member is rotated to move the head distally in the hole, when at least one thread is threaded into the threaded inner wall of the bone implant, at least a portion of the threaded inner wall is caught between the stop surface and the at least one thread. Bone fixation element, elongated along the central axis, contains a head and a stem. Stem is positioned with respect to the head in the distal direction and is configured to be inserted into the fixation site. Head forms a apex and at least one thread which is distal from the apex in the distal direction. Apex defines outer cross-sectional dimension in a direction intersecting the central axis and perpendicular to the central axis and at least one thread defines the largest diameter in the indicated direction, and the largest diameter of the at least one thread is smaller than the outer cross-sectional dimension of apex. Apex defines a conical stop surface which is configured to clamp the threaded inner wall of the bone implant between the apex and at least one thread of the head, when the head is screwed by thread in the distal direction into the bone fixing hole, which is at least partially formed by a threaded inner wall. Method of securing a bone fixation member to implant that includes first and second wire portions forming first and second threaded inner walls that define opening. Method comprises the steps of: inserting a core of a bone fixation member into the hole; at least one thread of the head of the bone fixing member is brought into contact with a corresponding at least one thread on the threaded inner wall; bone fixation member is rotated so that the head is threaded into the hole in the distal direction until the locking surface of the bone fixing member comes into contact with the implant; and after the locking surface has come into contact with the implant, the rotation of the bone fixation member continues so that the threaded inner walls are clamped between the stop surface and the at least one thread of the head.

EFFECT: inventors ensure that the bone implant is retained in the desired position on the proper tissue region.

19 cl, 6 dwg