CN201542728U - A Posterior Atlantoaxial Non-Fusion Internal Fixator - Google Patents

Abstract

The utility model relates to the technical field of medical instruments, and relates to a posterior atlantoaxial non-fusion internal fixator for orthopedic surgery. It consists of four pedicle universal screws (1), an atlas connecting rod (2), an axis connecting rod (3) and a universal fixing rod (4). The pedicle universal screws are respectively fixed on the left and right ends of the atlas connecting rod (2) and the axis connecting rod (3); the universal fixing rod (4) passes through the cylindrical hollow channel (413) of the head (41) respectively. ) and the square column hollow channel (421) of the body (42) connect the atlas connecting rod and the axis connecting rod as a whole. The utility model is simple in structure and easy to use. Because it only connects and fixes the atlas and axis, it retains the function of the atlas joint. Because the universal fixing rod limits the flexion and extension of the atlanto-axis, it achieves the purpose of reset and retains its function to the greatest extent. Normal physiological functions, but also reduce body damage and patient pain because no autologous bone graft is needed for fusion.

Description

A Posterior Atlantoaxial Non-Fusion Internal Fixator

technical field

The utility model relates to the technical field of medical instruments, and relates to a posterior atlantoaxial non-fusion internal fixator for orthopedic surgery.

Background technique

The atlas and axis are special vertebral segments in the cervical spine, and they are also important components of the occipital atlantoaxial complex. The atlantoaxial joint can perform axial rotation in a large range with the odontoid process as the axis, accounting for the entire cervical spine rotation. More than half of the range of motion, its rotational function is very important to the human body. However, the atlantoaxial and axial vertebrae are also prone to mechanical injuries, congenital deformities, tumors, tuberculosis, and rheumatoid diseases. The resulting instability of the atlantoaxial vertebrae and spinal cord compression is an important aspect of spinal surgery.

Posterior fusion is the main method to solve the instability of the atlantoaxial spine. Traditional fusion methods include: 1. Occipitocervical fusion: fix the upper cervical spine and occipital bone with nail rods (plates), and then use larger ilium bone grafts , this method is the earliest classical fusion, but it has a large trauma, a lot of bleeding, a high failure rate of internal fixation, and a low rate of bone graft fusion. At the expense of atlanto-occipital joints, atlanto-occipital joints and even more joints, the rotation function of the cervical spine is obviously limited after operation; 2. Atlantoaxial fusion: through various internal fixation methods (Gallie technique, Brooks technique, Mager1 technology, Harms technology, etc.) for internal fixation of the atlantoaxial vertebrae, and fusion of bone grafts between the atlantoaxial vertebrae to achieve long-term stability. With the improvement of internal fixation technology, its stability has been improved very well, and bone graft fusion has been added. This method can avoid long-term internal fixation of occipital-cervical fusion and preserve the function of the atlanto-occipital joint. It is currently the main method. However, autologous bone grafting is still required for fusion to cause certain trauma, and at the expense of the atlantoaxial joint function, the postoperative cervical rotation function is significantly limited.

Contents of the invention

The purpose of the utility model is to provide an atlantoaxial non-fusion internal fixator which can not only maintain the stability of the atlantoaxial spine, but also retain the rotation function of the atlantoaxial spine and does not need autologous bone graft for fusion.

The utility model is composed of four pedicle universal screws, an atlas connecting rod, an axis connecting rod and a universal fixing rod. The pedicle universal screw is composed of a nail body, a nut cap and a nut. The nut cap is hollow, and there are U-shaped grooves on both sides of the cap. The inner wall of the cap is provided with an internal thread, which matches the external thread of the nut. Hollow, the cross-section of the inner cavity is polygonal, usually hexagonal, so that it can be screwed into the nail cap with a matching hexagonal screwdriver; the atlas connecting rod is a solid cylindrical metal round rod, divided into left and middle , The three right sections, the middle section is thicker and curved in an arc shape, the left and right sections are slightly thinner, equal in length and thickness, and its outer diameter matches the width of the U-shaped groove on both sides of the pedicle universal screw cap, so that it can be inserted Fit the U-shaped groove and fix two pedicle universal screws to the two ends of the atlas connecting rod respectively; the connecting rod of the axis is also a solid metal rod, divided into left, middle and right sections, the middle section is thicker, It is in the shape of a square column; the left and right sections are cylindrical, equal in length and thickness, and its outer diameter matches the width of the U-shaped groove on both sides of the universal screw cap, so as to fit into the U-shaped groove and connect the other two. The universal screws of the pedicle are respectively fixed on the two ends of the connecting rod of the axis; the universal fixing rod is used to connect the connecting rod of the atlas and the connecting rod of the axis. The universal bearing structure is composed of a hollow oblate spherical shell and a universal joint in it. There are circular openings on the front and rear sides of the oblate spherical shell. The universal joint is spherical and can rotate in the oblate spherical shell. The circular opening of the channel and the circular opening of the oblate shell can be adjusted to the same direction. The diameter of the cylindrical hollow channel of the universal joint matches the outer diameter of the cylinder in the middle section of the atlas connecting rod, so that the atlas connecting rod The middle section of the universal fixed rod is inserted into it and can be slid to adjust the position; the body of the universal fixed rod is in the shape of a square column or other shapes, and there is a square column-shaped hollow channel in the middle, and the square openings at both ends of the channel and the flat spherical shell of the head In the same direction as the circular opening, the length, width, and height of the channel match the square column-shaped middle section of the axis connecting rod, so that the square column-shaped middle section of the axis connecting rod is placed here, and it is located at the vertical position in the middle of the channel on the back. There is also a screw hole communicating with the channel in the direction, and the screw hole is provided with an internal thread for screwing in a flat head nut matching it. The flat head nut is hollow, and the cross section of the inner cavity is polygonal, usually hexagonal, so A matching Allen screwdriver is screwed into the screw hole to secure the pivot rod.

The atlas connecting rod, the axis connecting rod and the universal fixing rod of the utility model can all be made of titanium alloy, and can also be made of other metals with good tissue compatibility and certain bending strength.

During the operation, the pedicle universal screws were implanted in the corresponding positions on the left and right sides of the atlas and axis according to the Harms technique, and the circular opening of the cylindrical hollow channel of the universal joint and the circular opening of the oblate shell were adjusted. After reaching the same direction, insert the atlas connecting rod to the middle section, and bend the middle section of the atlas connecting rod into a bow shape according to the curvature of the posterior arch of the atlas to fit the posterior arch of the atlas; The square column-shaped hollow channel of the body, and the square column-shaped middle section of the pivot connecting rod is placed in the square column-shaped hollow channel, and the flat head nut is screwed into the screw hole to lock the axis connecting rod, and then according to the universal fixed rod and the The position of the universal screw fixed on the pedicle of the axis is to bend the cylindrical parts on the left and right sides of the connecting rod of the axis from the opening of the square column hollow channel, and fit them into the pedicles of the left and right sides of the axis respectively. Tighten the nut to fix the U-shaped groove of the cap of the universal screw, and then reset the atlantoaxial dislocation under fluoroscopy, and then fix the two ends of the atlas connecting rod on the left and right sides of the implanted atlas according to the same method The universal screw of the pedicle achieves the purpose of reduction and fixation.

The utility model is simple in structure and easy to use. Since the internal fixator only connects and fixes the atlas and the axis, the segments are short, and the middle section of the atlas connecting rod can slide after being inserted into the universal joint of the universal fixing rod, so it retains The function of the atlantoaxial joint is improved. At the same time, because the universal fixation rod limits the flexion and extension of the atlantoaxial vertebrae, the purpose of reset is achieved, and because the universal bearing structure composed of the universal joint of the universal fixation rod and the atlas connecting rod can The rotation and lateral flexion functions of the atlantoaxial vertebrae are retained, so the non-fusion internal fixator is ideal for reduction, and its normal physiological functions are preserved to the greatest extent, and the curative effect is better; it also reduces the damage to the body because no autologous bone graft is needed for fusion and patient pain.

Description of drawings

Figure 1 is a schematic diagram of the overall structure of the utility model.

Fig. 2 is a schematic structural view of the universal screw of the present invention.

Fig. 3 is a structural schematic diagram of a nut matched with a universal screw of the present invention.

Fig. 4 is a structural schematic diagram of the atlas connecting rod of the present invention.

Fig. 5 is a schematic structural view of the axis connecting rod of the present invention.

Fig. 6 is a schematic diagram of the side structure of the universal fixed rod of the present invention.

Fig. 7 is a schematic diagram of the front structure of the universal fixed rod of the present invention.

Fig. 8 is a structural schematic diagram of a flat head nut matching with the screw hole of the universal fixed rod of the present invention.

Detailed ways

Now in conjunction with accompanying drawing and embodiment, the utility model is described in detail.

The utility model is composed of four pedicle universal screws 1, an atlas connecting rod 2, an axis connecting rod 3 and a universal fixing rod 4. Pedicle universal screw is made up of nail body 11, nail cap 12 and nut 13, and nail cap 12 is hollow, and the two sides of nail cap are provided with U-shaped groove 14, and the inner wall of nail cap is provided with internal thread, and this internal thread and nut 13 The external thread of the nut 13 is hollow, and the cross-section of the inner cavity is hexagonal, so that it can be screwed into the nut 12 with a matching hexagonal screwdriver; the atlas connecting rod 2 is a solid cylindrical metal round rod, Divided into left, middle and right sections, the middle section 21 is relatively thick and curved in an arc shape, and the left and right sections 22 are slightly thinner and equal in length and thickness, and its outer diameter is the same as the U-shaped groove on both sides of the pedicle universal screw cap. The width of 14 is matched so that the two pedicle universal screws are respectively fixed to the two ends of the atlas connecting rod in order to fit into the U-shaped groove; the pivot connecting rod 3 is also a solid metal round rod, divided into left, middle and Right three sections, middle section 31 is thicker, and it is square column, and left and right two sections 32 are cylindrical, equal length and thick, and its outer diameter matches with the width of the U-shaped groove on both sides of universal screw cap, to fit Fit the U-shaped groove to fix the other two pedicle universal screws to the two ends of the axis connecting rod respectively; the universal fixing rod 4 is used to connect the atlas connecting rod 2 and the axis connecting rod 3, and It consists of two parts, the head 41 and the body 42. The head is a universal bearing structure composed of a hollow oblate spherical shell 411 and a universal joint 412 inside. The front and rear sides of the oblate spherical shell are provided with circular openings, and the universal joint It is spherical and can rotate in the oblate spherical shell. There is a cylindrical hollow channel 413 through the front and back in the middle. The circular opening of the channel and the circular opening of the oblate spherical shell can be adjusted to the same direction. The universal joint cylindrical hollow channel 413 The diameter matches the cylindrical outer diameter of the middle section of the atlas connecting rod, so that the middle section of the atlas connecting rod is inserted therein and the position can be slidably adjusted; the body 42 of the universal fixing rod is a square column or other shapes, and the middle There is a square cylindrical hollow channel 421 that runs through the front and back. The square openings at both ends of the channel are in the same direction as the circular opening of the oblate spherical shell of the head. , so that the square column-shaped middle section of the pivotal connecting rod is placed here, a screw hole 422 communicating with the channel is also provided in the vertical direction at the middle position of the channel on the back side, and the screw hole is provided with an internal thread for screwing in with it. Matching flat-head nut 423, flat-head nut 423 is hollow, and the cross-section of the inner cavity is hexagonal, so that it can be screwed into the screw hole with a matching inner hexagonal screwdriver to fix the pivotal connecting rod.

Embodiment 1. A kind of posterior atlantoaxial non-fusion internal fixator

Universal screw nail body 11 of the present utility model is long 24mm, and external diameter is 3.5mm, and nail cap 12 inner diameters are 6.0mm, and nut 13 matches with it. The atlas connecting rod 2 is 55mm long, the middle section 21 has a diameter of 4.0mm and a length of 15mm, and the left and right sections 22 have a diameter of 3.0mm and a length of 20mm. The middle section 31 of the pivot connecting rod 3 is 10mm long, the cross section is square, and the side length is 4.0mm, and the left and right section 32 cylinders have a diameter of 3.0mm and a length of 30mm. The circle diameter of universal fixed rod 4 head 41 sides is 12mm, and the diameter of universal joint cylindrical hollow passage 413 is 4.2mm, and the frontal width of body 42 is 10mm, and side width is 8mm, and the length of square columnar hollow passage 421, Width and height match the middle section 31 of the pivot connecting rod 3, the diameter of the central screw hole on the back of the universal fixed rod is 6.0mm, and the inner hexagon nut 423 is matched with it, and the length is 2.0mm.

The utility model can be made into different specifications and models as required.

Claims (1)

1. way of escape extensive region dentata non-integration inner fixer, it is characterized in that forming by 4 universal screws of pedicle of vertebral arch (1), atlas pitman (2), dentata pitman (3) and universal fixed bar (4), the universal screw of pedicle of vertebral arch is made up of nail body (11), the head of a nail (12) and nut (13), head of a nail hollow, head of a nail both sides are provided with U-shaped groove (14), and head of a nail inwall is provided with female thread, the external screw thread coupling of this female thread and nut (13), nut hollow, the inner chamber cross section is polygon; Atlas pitman (2) is the solid cylindrical round metal bars, divide three sections of left, center, right, interlude (21) is thicker, be convexly curved, about two sections (22) slightly thin, isometric grade is thick, the width coupling of the universal screw head of a nail of its external diameter and pedicle of vertebral arch both sides U-shaped grooves (14), and it is embedded in this U-shaped groove two universal screws of pedicle of vertebral arch is individually fixed in atlas pitman two ends; Dentata pitman (3) also is the solid metal pole, divide three sections of left, center, right, interlude (31) is thicker, it is square column type, about two sections (32) cylindrical, isometric grade is thick, the width coupling of its external diameter and universal screw head of a nail both sides U-shaped grooves (14), and it is embedded in this U-shaped groove other two universal screws of pedicle of vertebral arch is individually fixed in dentata pitman two ends; Universal fixed bar (4) is used to connect atlas pitman (2) and dentata pitman (3), it is made up of head (41) and body (42) two parts, head is the universal bearing structure of being made up of hollow oblate spheroid shape shell (411) and the universal joint (412) in it, the two sides is provided with circular open before and after the oblate spheroid shape shell, it is spherical that universal joint is, can in oblate spheroid shape shell, rotate, the cylinder type hollow passage (413) that connects before and after the centre is provided with, the circular open of the circular open of passage and oblate spheroid shape shell can transfer to same direction, the diameter of universal joint cylinder type hollow passage (413) and atlas pitman interlude (21) external diameter coupling, the interlude of atlas pitman are inserted in it and are slidably adjusted the position; The body of universal fixed bar (42) is square column type, the square column type hollow passageway (421) that connects before and after the centre is provided with, the same direction of circular open of the square aperture at passage two ends and head oblate spheroid shape shell, the length of this passage, wide, high and dentata pitman square column type interlude (31) mates, dentata pitman square column type interlude places this, the vertical direction that is positioned at this passage centre position, the back side also is provided with the screw (422) that communicates with this passage, this screw is provided with female thread, be used to screw in flat nut (423) with its coupling, flat nut (423) hollow, the inner chamber cross section is polygon, it is screwed in the screw, with fixing dentata pitman.

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