RU2234278C2 - Device for carrying out frontal vertebrae fixation - Google Patents

Abstract

FIELD: medical engineering.

SUBSTANCE: device has two overlay members adapted to anterolateral surfaces of vertebral bodies. The overlay members have two or three conic central and through threaded holes, bone screws having conic heads, plate with two through end holes and fixing screws. The bone screws are introduced into the through holes in the overlay members. Rectangular slots are produced in the overlay members, one of them having a dead slot and the other one having through slot, both matching the end parts of the plates in size. One of through holes in the end part of plate is oval. Parallel teeth arranged in perpendicular to lateral walls are produced on the plate end part surface and on through slot surface of one of the overlay members.

EFFECT: enhanced effectiveness in fixing anchoring vertebral bodies with different diastasis value and retained correction angle.

8 dwg

Description

The invention relates to medicine, namely to traumatology and orthopedics.

A device for fixing the thoracolumbar spine, containing a plate with holes having a conical and threaded cylindrical parts, fixing screws in the form of threaded rods with conical heads connected by threaded necks.

The disadvantages of this device is that the end parts of the plate are not adapted to the anterolateral curvature of the bodies of the supporting vertebrae, after installing the plate, it is impossible to adjust the degree of compression of the interbody graft. In addition, plates of different sizes are needed for more accurate adaptation with different values of diastasis between the supporting vertebrae.

A device for fixing the spine, containing two pads with through threaded and through holes located perpendicular to the threaded, bone screws with conical heads connected by threaded necks inserted into through threaded holes in the pads, axial rods inserted into the through holes of the pads, axial rod stopper in the form of screws inserted into additional threaded holes of the pads and blocking axial rods in the through holes.

A disadvantage of the known device is that it is difficult to adapt the axial rods in the through holes of the linings when they are not parallel, which in turn requires bending and fitting, the locking screws do not provide reliable fixation of the rods in the through holes of the linings under axial load.

Closest to the claimed is a device for anterior fixation of the thoracolumbar spine, containing two plates adapted to the anterolateral surfaces of the vertebral bodies with two or three conical shaped through and central threaded holes, bone screws with conical shaped heads inserted into the through holes in the lining, a plate with two through holes at the ends and fixing screws.

The disadvantages of the known device is that it is difficult to adapt the end elements of the plates with radial teeth to the plates with intermediate angles of rotation relative to the Central threaded holes and different lengths of the diastasis between the plates. Their forced fixation leads to excessive kyphotic or lordotic deformation of the operated segment of the spine. In this case, either excessive compression of the interbody graft occurs, or its instability between the vertebral bodies, which leads to a redistribution of loads between the graft and bone screws. In addition, during cyclic loading in the postoperative period, it is possible to weaken the fixation of the end sections of the plates relative to the central threaded holes of the plates with their subsequent angular displacement.

The aim of the present invention is to ensure the reliability of the fixation of the bodies of the supporting vertebrae at various diastases between them while maintaining a given angle of correction of the spine.

This goal is achieved by the fact that in the known device containing two plates adapted to the anterolateral surfaces of the vertebral bodies with two or three conical shaped through and central threaded holes, bone screws with conical shaped heads inserted into the through holes in the overlays, a plate with two through holes at the ends and fixing screws, in the overlays are grooves of rectangular cross section, blind on one and through to the other, corresponding in size to the end parts of the plates, one of the through holes tures in an end portion of the plate formed oval, and on the surface of the end portion of the plate from the oval hole and on surface of the through groove of one of the pads formed parallel tines, perpendicular side walls.

In FIG. 1 shows a device for anterior fixation of the vertebrae assembly;

in FIG. 2 - plate, rear view;

in FIG. 3 - plate, side view;

in FIG. 4 - pad with a through groove, side view;

in FIG. 5 - overlay with a through groove, front view;

in FIG. 6 - pad with a blind groove, side view;

in FIG. 7 - pad with a blind groove - front view;

in FIG. 8 is a section AA in FIG. 1.

A device for anterior vertebral fixation consists of pads 1 and 2 with an adapted surface 3 to the anterolateral parts of the vertebral bodies, a blind groove 4 of rectangular section on the pad 1 and a through groove 5 on the pad 2, with parallel teeth 6 on the surface of the through groove 5, perpendicular to the side walls 7, through-conical holes 8 and a central threaded hole 9 in the lining 1 and 2, bone screws 10 inserted into the through-hole 8 in the lining 1 and 2, the plate 11 with a through hole 12 in one part and a through oval th 13 in another, parallel teeth 14 on the surface side through the oval hole 13 perpendicular to the side walls 15, locking screws 16, introduced into the through hole 12 and through the oval hole 13 of the plate 11 and the threaded central hole 9 overlays 1 and 2.

The proposed device for anterior fixation of the vertebrae is used as follows.

Under general anesthesia, surgical access is made to the anterolateral surface of the bodies of the affected segment of the spine, the vertebra is localized, and its complete or partial removal is performed. Anterior corporodesis is performed with an auto- or allograft with restoration of the physiological curvature of the spine. The device for fixing the vertebrae is pre-assembled without bone screws with an installation size corresponding to the distance between the bodies of the supporting vertebrae. The end part of the plate 11 is inserted into the blind groove 4 of the lining 1 and fixed with a screw 16 through the through hole 12 to the lining 1 in the central threaded hole 7, the other end of the plate 11 with the through oval hole 13 and parallel teeth 14, perpendicular to the side walls 15, is inserted into the through groove 5 and, moving along parallel teeth 6, perpendicular to the side walls 7, to the installation size, fix with a screw 16 in the central threaded hole 7 of the lining 2. Apply the device to the anterolateral sections of the vertebral bodies adapt surface 3, choosing the position of the best adaptation of the pads, mark their position with a marker, then unscrew the fixing screws 16, remove the plate 11 from the grooves 4 and 5 of the pads 1 and 2. According to the marked positions, the pads are fixed to the vertebral bodies using a template guide through the conical the shape of the hole 8 with bone screws 10. Re-insert the plate 11 into the grooves 4 and 5 of the lining 1 and 2, respectively, the initial position and after compression of the vertebral bodies are fixed with screws 16 in the central threaded holes 9 Adok 1 and 2. After confirming the rigidity fixation device assembled vertebral bodies reference postoperative wound is sutured.

The use of this device will ensure reliable fixation of the bodies of the supporting vertebrae with different values of diastasis between them while maintaining the specified angle of correction of the spine.

Claims (1)

A device for anterior fixation of the vertebrae containing two plates, adapted to the anterolateral surfaces of the vertebral bodies, with two or three conical through and central threaded holes, bone screws with conical heads inserted into the through holes in the overlays, a plate with two through holes at the ends and fixing screws, characterized in that the overlays are made of grooves of rectangular cross section, blind on one and through to the other, corresponding in size to the end parts of the plates, one of kvoznyh holes in the end portion of the plate formed oval, and on the surface of the end portion of the plate from the oval hole and on surface of the through groove of one of the pads formed parallel tines, perpendicular side walls.

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