CN201710445U

CN201710445U - Improved anterior cervical plate fixing device

Info

Publication number: CN201710445U
Application number: CN2010200270402U
Authority: CN
Inventors: 欧阳钧; 陈春; 李鉴轶; 赵卫东; 孙培栋
Original assignee: Southern Medical University
Current assignee: Southern Medical University
Priority date: 2010-01-20
Filing date: 2010-01-20
Publication date: 2011-01-19
Anticipated expiration: 2020-01-20

Abstract

The utility model discloses an improved anterior cervical plate fixing device which is characterized in that the middle parts of the two ends of a fixed plate (1) are respectively provided with a tapered inclined hole (4) provided with a self-tapping screw (2); the end surfaces of the two ends are provided with screw holes (5) used for mounting locking screws (3); the screw holes (5) are communicated with the tapered inclined holes (4); the included angle beta between the axis n of the tapered inclined hole (4) on the fixed plate (1) and one side of the longitudinal section p of the fixed plate (1) is within the range of 31+/-1-2 degrees to 48+/-1-2 degrees; the included angle alpha between the axis n of the tapered inclined hole (4) on the fixed plate (1) and the lower side of the transverse section q of the fixed plate (1) is within the range of 1+/-1-2 degrees to 15+/-1-2 degrees; included angle beta' between the axis n of the tapered inclined hole (4) under the fixed plate (1) and the other side of the longitudinal section p of the fixed plate (1) is within the range of 31+/-1-2 degrees to 48+/-1-2 degrees; the included angle alpha' between the axis n of the tapered inclined hole (4) under the fixed plate (1) and the lower side of the transverse section q of the fixed plate (1) is within the range of 1+/-1-2 degrees to 15+/-1-2 degrees; beta'-beta=1-2 degrees, and alpha'- alpha=1-2 degrees; screw caps of the self-tapping screws (2) are cones matched with the tapered inclined holes (4); and the locking screws (3) are locating screws.

Description

A kind of modified model anterior plate fixation fixture

Technical field

This utility model relates to a kind of surgical instruments, is specifically related to the spinal column localizer, particularly relates to the anterior plate fixation fixed system.

Background technology

In the cervical spine injury treatment, what generally use both at home and abroad at present is through preceding road vertebral body screw steel plate system, after row preceding road intervertebral disc or the vertebral resection decompression bone-graft fusion, the using cervical vertebra anterior plate is fixed, can keep the cervical vertebra strength of fixation, it is stable immediately to be maintained fixed the stage, prevents the trachelokyphosis teratogenesis.This technology has improved fusion rate of bone graft, has reduced the plant bone mass rate of subsiding, and can prevent the displacement of bone piece, and dwindle range of fusion.But in osteoporotic patient, some further descends because of vertebral body bone amount and bone strength, and the cervical vertebral body bony structures no longer has weight-bearing function, when adopting the vertebral body screw to reset fixing fracture, easily causes screw loosening and comes off, and causes the failure of internal fixation.

Office's Granted publication on April 9th, 2003 has been known " the preceding road self-locking of a kind of novel cervical vertebra inner fixing device " (Granted publication number for CN 2543495Y) by state, and this device will be fixed in epicentral tapping screw by one steel plate, some pieces and lock-screw is formed.Though above-mentioned patent scheme can be with on the firmly fixed neck bone of the bone material of bone-graft fusion, prevent the trachelokyphosis teratogenesis, but wherein said steel plate is that to shoot vertebral body by tapping screw fixed, therefore screw loosening very easily takes place for osteoporotic patient come off and fail.State knows that office went back Granted publication on August 26th, 2009 " a kind of strength vertebra anterior plate fixed system " (Granted publication number be CN 201295280Y), and the nail-plate structure of this system and above-mentioned utility model patent scheme are basic identical, have identical problem too.

" cervical vertebra under preceding road (C3～C7) design and the biomechanical analysis of inner fixer " literary composition of delivering of 2005 the 2nd the 7th phases of volume of China's contemporary surgery magazine has disclosed a kind of anterior plate fixation system of designs such as Li Cheng, the principal character of this system is to adopt swell fixture to fix, to strengthen the curable grip of vertebral body and screw, things turn out contrary to one's wishes but this measure remains for sufferers of osteoporosis face.

Summary of the invention

In view of there is above-mentioned deficiency in present technology, technical problem to be solved in the utility model is to improve the bonding strength of screw and vertebral body in the anterior plate fixation system, causes fixing the failure to avoid screw loosening to come off.

The technical scheme that this utility model addresses the above problem is as follows:

A kind of modified model anterior plate fixation fixture, this device is made up of fixing head, tapping screw and lock screw, it is characterized in that,

The middle part at fixing head two is respectively equipped with the taper inclined hole of an installation tapping screw, the end face at two is provided with the screw that lock screw is installed, this screw is communicated with described taper inclined hole, wherein, being positioned at fixing head the higher authorities' the axis n of taper inclined hole and the angle β of fixing head vertical section p one side is 31 ° ± 1～2 ° to 48 ° ± 1～2 °, with the angle α of fixing head cross section q downside be 1 ° ± 1～2 ° to 15 ° ± 1～2 °; Be positioned at following the axis n of taper inclined hole and the angle β ' of fixing head vertical section p opposite side of fixing head and be 31 ° ± 1～2 ° to 48 ° ± 1～2 ° and be, with the angle α ' of fixing head cross section q downside be 1 ° ± 1～2 ° to 15 ° ± 1～2 °; And, β '-β=1～2 °, α '-α=1～2 °;

The head of a nail of tapping screw is the cone that is complementary with described taper inclined hole;

Lock screw is a dog screw.

Fixture described in the utility model, wherein, the positioning head of described lock screw is a bulb, the outer surface of the head of a nail of described tapping screw is densely covered with the crown recess that the positioning head with described lock screw is complementary.

People's neck bone has 7, be respectively C1～C7 from top to bottom, cervical vertebra down during the pathological changes that need carry out preceding road bone grafting concentrates on usually, be 5 sections of C3～C7, therefore, the anterior plate fixed system normally will cover epicentral fixing head and adopt tapping screw to be fixed on the vertebral body of C3～C7 sections.In order to seek strong fixed means, the inventor furthers investigate the structure of neck bone, find by actual measurement a large amount of human cervical spine bone samples, the angle in the pedicle of vertebral arch that links to each other with vertebral body and the vertical section of body of cervical vertebra (making it is β) is 31 °～48 °, and increase progressively with 2 °～3 ° from sections C3 to C7, with the angle (making it is α) of the cross section downside of body of cervical vertebra then be 1 °～15 °, and increase progressively with 1 °～2 ° from sections C3 to C7; For different individual patients, the deviation at described α and β angle is about 1 °～2 °, promptly ± 1～2 °.Based on above-mentioned result of study, this utility model is designed to taper with the installing hole that tapping screw is installed on the fixing head, and make the incline direction of its axis and the bearing of trend basically identical of pedicle of vertebral arch, so that the tapping screw that matches can be shot closely knit pedicle of vertebral arch through loose vertebral body.Because the pedicle of vertebral arch of patients with osteoporosis is relatively closely knit and hard than vertebral body, and the more traditional vertebral body nail of the length of nail increases, increased the nail contact area effectively, strengthened fixed firmness, although therefore can only wear a tapping screw for one of fixing head of the present utility model, its firm degree than prior art is predictable.

Description of drawings

Fig. 1～5 are the structural representation of a specific embodiment of fixing head described in the utility model, and wherein, Fig. 1 is a front view, Fig. 2 is the profilograph of Fig. 1, Fig. 3 is the A A cutaway view of Fig. 1, and Fig. 4 is the B-B cutaway view of Fig. 1, and Fig. 5 is the C-C profile (amplification) of Fig. 1.

Fig. 6 is the structural representation of a specific embodiment of tapping screw described in the utility model.

Fig. 7～11 are the assembly structure sketch map of a specific embodiment of modified model anterior plate fixation fixture described in the utility model, wherein, Fig. 7 is a front view, Fig. 8 is the F F cutaway view of Fig. 7, Fig. 9 is the D-D cutaway view of Fig. 7, Figure 10 is the EE cutaway view of Fig. 7, and Figure 11 is the G-G profile (amplification) of Figure 10.

Figure 12 and Figure 13 are the assembly structure sketch map of another specific embodiment of modified model anterior plate fixation fixture described in the utility model, wherein, Figure 12 is a front view, and Figure 13 is the H-H cutaway view of Figure 12, Figure 14 is the J-J cutaway view of Figure 12, and Figure 15 is the K-K cutaway view of Figure 12.

The specific embodiment

Example 1

Shown in Fig. 7～11, present embodiment is the single-unit section anterior plate fixation fixture that is fixed in neck bone C3 and C4 sections, and wherein, fixing head 1 is shown in Fig. 1～5, and tapping screw 2 as shown in Figure 6.

Referring to Fig. 1～5, it is 5 ° taper inclined hole 4 that the middle part at fixing head 1 two is respectively equipped with a cone angle gamma, and the end face at two is provided with screw 5, and this screw 5 is communicated with described taper inclined hole 4.In the described taper inclined hole 4, being positioned at fixing head 1 the higher authorities' the axis n of taper inclined hole 4 and the angle β in fixing head 1 vertical section p left side is 36 °, with the angle α of fixing head 1 cross section q downside be 4 °; Be positioned at fixing head 1 following the axis n of taper inclined hole 4 and the angle β ' on p right side, fixing head 1 vertical section be 38.5 °, with the angle α ' of fixing head 1 cross section q downside be 5.5 °.

Referring to Fig. 6, tapping screw 2 is a hexagon socket countersunk flat cap head screw, its head of a nail for fixing head 1 on the cone that is complementary of taper inclined hole 4; The cone angle gamma of described cone ' also be 5 °, the surface is provided with the crown recess 6 that the positioning head with described lock screw 3 is complementary.

Referring to Figure 11, lock screw 3 is common cross recess countersunk head dog screw.

Example 2

Referring to Figure 12～Figure 15, present embodiment is the two segment anterior plate fixation fixture that is fixed in neck bone C3 and C5 sections.The following structure in addition of this example is identical with example 1:

The length of fixing head 1 is for can cover neck bone C3 and C5 sections; The angle β that is positioned at axis (promptly being positioned at the axis of fixing head 1 the higher authorities' the taper inclined hole 4) n of fixing head 1 the higher authorities' tapping screw 2 and fixing head 1 vertical section p left side is 36 °, with the angle α of fixing head 1 cross section q downside be 4 °; Be positioned at fixing head 1 following axis (promptly be positioned at fixing head 1 following the axis of the taper inclined hole 4) n of tapping screw 2 and the angle β ' on p right side, fixing head 1 vertical section be 41 °, with the angle α ' of fixing head 1 cross section q downside be 7 °.

Claims

1. modified model anterior plate fixation fixture, this device is made up of fixing head (1), tapping screw (2) and lock screw (3), it is characterized in that,

The middle part at fixing head (1) two is respectively equipped with the taper inclined hole (4) of an installation tapping screw (2), the end face at two is provided with the screw (5) that lock screw (3) is installed, this screw (5) is communicated with described taper inclined hole (4), wherein, being positioned at fixing head (1) the higher authorities' the axis n of taper inclined hole (4) and the angle β of fixing head (1) vertical section p one side is 31 ° ± 1～2 ° to 48 ° ± 1～2 °, with the angle α of fixing head (1) cross section q downside be 1 ° ± 1～2 ° to 15 ° ± 1～2 °; Be positioned at following the axis n of taper inclined hole (4) and the angle β ' of fixing head (1) vertical section p opposite side of fixing head (1) and be 31 ° ± 1～2 ° to 48 ° ± 1～2 ° and be, with the angle α ' of fixing head (1) cross section q downside be 1 ° ± 1～2 ° to 15 ° ± 1～2 °; And, β '-β=1～2 °, α '-α=1～2 °;

The head of a nail of tapping screw (2) is the cone that is complementary with described taper inclined hole (4);

Lock screw (3) is a dog screw.

2. according to 1 described a kind of modified model anterior plate fixation fixture as requested, it is characterized in that, the positioning head of described lock screw (3) is a bulb, and the outer surface of the head of a nail of described tapping screw (2) is densely covered with the crown recess (6) that the positioning head with described lock screw (3) is complementary.