A kind of pedicle nailTechnical field
The present invention relates to orthopedic medical device field, especially a kind of pedicle nail.
Background technology
The application of pedicle nail in spinal operation in recent years gets more and more, and is applicable to the diseases such as treatment thoracic and lumbar vertebral posterior short segment wound, tumor and unstable spine.Current pedicle nail, primarily of U-shaped nail, locking jackscrew and nail rod composition.The locking mode of its nail rod, by the screw-internal thread fit on the U-shaped nail seat two side of jackscrew and U-shaped nail and pressing pin is excellent, need to rotate jackscrew many circles during pressing pin rod, extend operating time, and, when coupling mechanism force is larger, also can make nail seat two side softened or support distortion, cause stripped thread phenomenon, thus cause nail rod loosen or exit, make operative failure, and, postoperative time return period is longer, during this, human body needs activity, can make pedicle nail that long fine motion occurs, thus simple jackscrew directly compresses mode, also there is the possibility loosening and even move back rod, and structural volume is larger, be unfavorable for stitching and the treatment of otch.
Summary of the invention
The invention discloses a kind of pedicle nail, overcome above-mentioned defect, it mainly comprises U-shaped nail, lock nut, lock dog and nail rod, described U-shaped nail is provided with screw division, described screw division upper end is provided with nail seat, described nail seat outer rim is provided with two and holds nail, described nail seat upper end is provided with the U-type groove of blind hole and through blind hole and nail seat side, described nail rod is placed in bottom described U-type groove, described lock dog lower end is provided with through side and the V-type groove that Open Side Down, described lock dog is placed in described blind hole, and described V-type groove bandit is on described nail rod, described lock dog upper end is provided with screw rod, described lock nut is provided with screw and is threaded onto on described screw rod, described screw upper end is provided with tooling hole, lock nut is rotated for fastening means, it is characterized in that: the inner side of described U-type groove two wall is provided with cannelure, described lock nut outer rim is arranged with two boss, described two boss screw in described cannelure by U-type groove simultaneously, its rotation direction is contrary with the thread rotary orientation of the screw of described lock nut, make while the described lock nut of rotation, described lock dog advances downwards and locks described nail rod.Conveniently described boss screws in described cannelure, guiding surface is provided with on the upside of described boss, this inclined-plane also can make described lock nut advance downwards and assist described lock dog pressing pin rod, described cannelure is provided with spacer pin and screws out cannelure to prevent described boss, the upper side of described cannelure is set to inclined-plane, make bottom land wider than notch, described boss shape is set to the shape identical with described cannelure and matches with cannelure, described cannelure also can be set to dovetail groove or T-slot or L-type groove, simultaneously described boss is also set to swallow-tail form or T-shaped or L-type and described dovetail groove or T-slot or L-type groove respectively and matches, for preventing described U-type groove two side to be outwards out of shape, described boss is deviate from from described cannelure, thus the defect overcome existing for current pedicle nail.Structure of the present invention is simple, easy to operate, coordinates reverse thread to advance will follow closely excellent locking, and not only save operating time, and lock solid and reliable, thus improve the success rate of operation through lock nut small angle rotation.
Accompanying drawing illustrates:
Fig. 1 is the schematic diagram of a kind of pedicle nail of the present invention;
Fig. 2 is the partial sectional view of U-shaped nail in Fig. 1;
Fig. 3 is the schematic diagram of lock dog in Fig. 1;
Fig. 4 is the schematic diagram of lock nut in Fig. 1.
Fig. 5 is the sectional view of Fig. 4;
In accompanying drawing: 1U sprig, 2 lock nuts, 3 lock dogs, 4 spacer pins, 1-1 cannelure, 1-2 blind hole, 1-3 pin-and-hole, 2-1 boss, 2-2 screw, 2-3 tooling hole, 2-4 inclined-plane, 3-1V type groove, 3-2 screw rod.
Embodiment:
Fig. 1 to Fig. 5 shows the embodiment of a kind of pedicle nail of the present invention.
A kind of pedicle nail of the present invention, mainly comprise U-shaped nail 1, lock nut 2, lock dog 3 and nail rod, described U-shaped nail 1 is provided with screw division, described screw division upper end is provided with nail seat, described nail seat outer rim is provided with two and holds nail, described nail seat upper end is provided with the U-type groove of blind hole 1-2 and through blind hole 1-2 and nail seat side, described nail rod is placed in bottom described U-type groove, described lock dog 3 lower end is provided with through side and the V-type groove 3-1 that Open Side Down, described lock dog 3 is placed in described blind hole 1-2, and described V-type groove bandit is on described nail rod, described lock dog 3 upper end is provided with screw rod 3-2, described lock nut 2 be provided with screw 2-2 and revolve with described screw rod 3-2 on, described screw 2-2 upper end is provided with tooling hole 2-3, lock nut is rotated for fastening means, it is characterized in that: the inner side of described U-type groove two wall is provided with cannelure 1-1, two boss 2-1 are arranged with outside described lock nut 2, described two boss 2-1 screw in described cannelure 1-1 by U-type groove simultaneously, its rotation direction is contrary with the thread rotary orientation of described lock nut 2 screw 2-2, make while the described lock nut 2 of rotation, described lock dog 3 advances the described nail rod of locking downwards.Conveniently described boss 2-1 screws in described cannelure 1-1, guiding surface 2-4 is provided with on the upside of described boss 2-1, this inclined-plane 2-4 also can make described lock nut 2 advance downwards and assist pressing pin rod, described cannelure 1-1 is provided with pin-and-hole 1-3, for mounting limit pin 4, cannelure 1-1 is screwed out to prevent described boss 2-1, the upper side of described cannelure 1-1 is set to inclined-plane, make bottom land wider than notch, described boss 2-1 shape is set to the shape identical with described cannelure 1-1 and matches with cannelure 1-1, described cannelure 1-1 also can be set to dovetail groove or T-slot or L-type groove, simultaneously described boss 2-1 is also set to swallow-tail form or T-shaped or L-type and described dovetail groove or T-slot or L-type groove respectively and matches, for preventing described U-type groove two side to be outwards out of shape, described boss 2-1 is deviate from from described cannelure 1-1.