WO2010102462A1

WO2010102462A1 - Pedicle screw, nut and locking thread at the tail part of screw

Info

Publication number: WO2010102462A1
Application number: PCT/CN2009/071255
Authority: WO
Inventors: 李明; 贺石生; 胡火星
Original assignee: Li Ming; He Shisheng; Hu Huoxing
Priority date: 2009-03-10
Filing date: 2009-04-14
Publication date: 2010-09-16
Also published as: CN101502439A; CN101502439B

Abstract

A pedicle screw, a nut and a locking thread at the tail part of the screw, in which the thread profile of the locking thread for use at the tail part of said pedicle screw has an L-shaped section. The inner thread at said tail part of pedicle screw is said locking thread. Nut(3) has a out thread(4), the out thread(4) mates said inner thread, after the out thread(4) of the nut(3) screws in the inner thread of the tail part of pedicle screw, the inner thread(2) at said tail part of pedicle screw(1) engages with the out thread(4) of the nut(3). When locking, the thread of tail part of the screw and the thread of the nut can reduce the tension of the head of the screw, it is convenient to lock and take out the nut by an inner core of the nut, and it can avoid nut loosing and nut cracking.

Description

Locking thread for pedicle screw, nut and its tail

The present invention relates to a connecting element for a medical device, and in particular to a locking thread of a pedicle screw tail and a nut thereof. Background technique

The use of internal fixation devices has greatly advanced the development of spinal surgery. The pedicle screw internal fixation system is one of the most widely used internal fixation devices in spinal surgery. The locking thread of the existing pedicle screw tail has the disadvantages of easy sliding, incomplete locking, easy cracking of the nail cap, and the like, and the cost is high. Summary of the invention

It is an object of the present invention to provide a locking thread for the pedicle screw tail to enhance the connection stability of the pedicle screw.

Another object of the present invention is to provide a pedicle screw that has a locking thread that is not easily slippery.

Another object of the present invention is to provide a nut that is coupled to a pedicle screw having a stable connection structure.

The locking thread for the pedicle screw tail of the present invention is characterized in that the tooth shape of the locking thread has an L-shaped cross section.

The locking thread is further characterized in that the L-shaped cross section includes a first folding angle, a first lateral side, a second folding angle, a second vertical side, a third folding angle, a second lateral side, and a fourth folding angle which are sequentially connected The third vertical side, the fifth vertical angle, the third lateral side, and the sixth chamfer are referenced to the vertically placed pedicle screw, and the inclination of the second vertical side and the third vertical side to the horizontal plane is >0° and <180 . (eg: 30. , 45 ° , 60 . , 90 . , 135 ° , 120 ° , 150 ° ) , the inclination of the first lateral edge , the second lateral edge and the third transverse edge to the vertical plane > 0 ° and < 180 ° (eg 30°, 45 °, 60°, 90°, 135 °, 120°, 150°).

The locking thread is further characterized in that the third angle is 0 degrees and 180 degrees, and when the third angle is 0 degrees, the second side and the second side are coincident as a straight line.

The locking thread is further characterized in that: the first chamfer, the second chamfer, the third chamfer, the fourth chamfer, the fifth chamfer and the sixth chamfer are at right angles, acute angles, obtuse angles, flat angles, arcs or polygons One. The locking thread is further characterized in that the tooth shape of the locking thread further has another L-shaped cross section, and the other L-shaped cross section and the L-shaped cross section are symmetric to form a T-shaped cross section.

The pedicle screw of the present invention has an internal thread at its tail, which is characterized in that the internal thread is the aforementioned locking thread.

The nut of the present invention has an external thread which is complementary to the aforementioned internal thread. After the external thread of the nut is screwed into the internal thread of the pedicle screw tail, the internal thread of the pedicle screw tail and the nut are The external threads are closely fitted to each other.

The method of use of the invention is as follows: First, the pedicle screw is screwed into the pedicle to be fixed, and then the connecting rod is placed in the tail groove of the pedicle screw, and the nut is screwed into the pedicle screw head. Department, tighten the nut to complete the lock.

The invention has the advantages that: the invention is mainly used for patients requiring screw internal fixation for spinal surgery, and its main advantages are: the screw tail and the nut thread design can play the role of reducing the tension of the screw head when locking, nut The inner core facilitates the locking and removal of the nut and prevents the slipper and nut from cracking.

The invention has the advantages of simple structure, novel concept, convenient processing and stable performance. BRIEF abstract

Specific features and properties of the present invention are further exemplified by the following examples and the accompanying drawings.

Figure 1 is a perspective view of a pedicle screw of the present invention.

Figure 2 is a perspective view of the nut of the present invention.

Figure 3 is a schematic illustration of the profile of the internal thread of the pedicle screw tail of the present invention.

Figure 4 is a schematic illustration of the profile of the external thread of the nut of the present invention.

Fig. 5 is a schematic view showing the oblique direction of the first vertical side, the second vertical side or the third vertical side of the internal thread of the pedicle screw tail and the horizontal plane. Among them, (a) is an inclination angle of 90°, (b) is an inclination angle of 0-90°, and (c) is an inclination angle of 90. -180. .

Fig. 6 is a schematic view showing the oblique direction of the first lateral side, the second lateral side or the third lateral side and the vertical plane of the internal thread of the pedicle screw tail. Wherein (a) is an inclination of 90°, (b) is an inclination of 0-90°, and (c) is an inclination of 90. -180. .

7 is a partial schematic view showing a possible shape of a first angle, a second angle, a third angle, a fourth angle, a fifth angle, or a sixth angle of the internal thread of the pedicle. (a) is an arc, (b) is a right angle, (c) is an acute angle, (d) is an obtuse angle, and (e) is a polygon. Fig. 8 is a schematic view showing a plurality of variations of the internal thread of the pedicle tail. (a) is a standard L-shaped thread. (b) is a standard T-thread. (c) When the third angle is at a flat angle (0 degree angle), the second vertical side and the second horizontal side are on the same straight line. (d) When the third angle is at a flat angle (0 degree angle), the second vertical side and the second horizontal side are on the same straight line, and are two-sided T-shaped threads. (e) is the first angle, the sixth angle and the fourth angle are arcs, the third angle is an acute angle, and the second vertical side and the third horizontal side are oblique lines.

(f) is the first chamfer, the sixth chamfer is a polygon, the fourth chamfer is an obtuse angle, the third chamfer is an acute angle, and the third lateral side is a combined schematic diagram of the oblique line.

Fig. 9 is a schematic view showing a plurality of variations of the profile of the external thread of the nut. (a) is a schematic view of the external thread corresponding to (a) of FIG. 8, (b) is a schematic view of the thread shape corresponding to FIG. 8(b), and (c) is corresponding to FIG. 8(c). Schematic diagram of the thread shape, (d) is a schematic diagram of the thread shape corresponding to Fig. 8 (d), (e) is a schematic diagram of the thread shape corresponding to Fig. 8 (e), and (f) is the thread shape corresponding to Fig. 8 (f) schematic diagram.

Figure 10 is a schematic view showing the combination of the screw tail 1 and the nut 2.

In the figure, the label is: 1 is the screw tail, 2 is the internal thread of the screw tail, 3 is the nut, 4 is the external thread of the nut, 5 is the groove of the internal thread of the screw tail, 6 is the protrusion of the external thread of the nut, 7 is the screw The first vertical side of the internal thread of the tail, 8 is the first angle of the internal thread of the screw tail, 9 is the first lateral side of the internal thread of the screw tail, 10 is the second corner of the internal thread of the screw tail, and 11 is the internal thread of the screw tail. The second vertical side, 12 is the third angle of the internal thread of the screw tail, 13 is the second lateral side of the internal thread of the screw tail, 14 is the fourth angle of the internal thread of the screw tail, and 15 is the third vertical side of the internal thread of the screw tail 16 is the fifth angle of the internal thread of the screw tail, 17 is the third lateral side of the internal thread of the screw tail, 18 is the sixth angle of the internal thread of the screw tail, and 19 is a bump. BEST MODE FOR CARRYING OUT THE INVENTION

The invention is further illustrated by the following examples.

The pedicle screw locking thread of the present invention is an internal thread 2 located at the pedicle screw tail 1 and has the structure shown in FIG. The structure of the external thread 4 of the nut 3 is as shown in Fig. 2, and the internal thread 2 and the external thread 4 are closely fitted to each other. The internal thread 2 is a spiral-shaped continuous groove portion having an L-shaped cross section formed on a cylindrical surface, and the external thread 4 is a spiral-shaped continuous projection having an L-shaped cross section formed on the cylindrical surface. section. The internal thread 2 and the external thread 4 have a complementary structure, so that the following description of one of the internal thread 2 and the external thread 4 is also applicable to the other.

The vertebral root screws shown in Figure 3 are placed in a vertical position, and only the two enlarged magnifications are shown in the figure. The shape of the tooth, but it is thus conceivable that the cross-sectional shape of the tail of the vertebral root screw is completely cut. The root (or the crest) of the internal thread 2 of the screw tail 1 is provided with a recess 5, and accordingly, a projection 6 is provided on the crest of the external thread 4 on the nut 3. The groove 5 and the protrusion 6 may be single-sided or double-sided. If it is single-sided, the internal thread 2 of the screw tail 1 and the external thread 4 of the nut 3 are generally L-shaped, as shown in FIG. 3 and As shown in Fig. 4, if the internal thread 2 of the screw tail 1 on both sides and the external thread 4 on the nut 3 are substantially T-shaped, as shown in Fig. 8(b) and Fig. 9(b).

With continued reference to FIG. 3, the L-shaped profile has a first angle 8, a first lateral edge 9, a second angle 10, a second vertical edge 11, a third angle 12, a second lateral edge 13, and a fourth folding angle 14. The third vertical side 15, the fifth corner 16, the third side 17 and the sixth corner 18 are connected in sequence.

The first vertical side 7 is provided on the bump 19, and the first vertical side 7 is connected to the first corner 8 and the sixth corner 18 of the other tooth, respectively.

Figures 3 and 4 show a preferred embodiment, and the embodiment shown in Figures 3 and 4 has various variations. For example, the first vertical side 7, the second vertical side 11 and the third vertical side 15 may each be perpendicular or inclined to the horizontal plane, and have an inclination of >0° and <180°, such as: 30°, 45°, 60°, 90°, 135°, 120°, 150°, ( _a ), (b), and (c) in Fig. 5 exemplify this case. When the third chamfer 12 is at a flat angle (0 degree angle), the second vertical side 11 and the second lateral side 13 are on the same straight line as shown in Fig. 8(c). The first lateral side 9, the second lateral side 13 or the third lateral side 17 may be inclined horizontally or horizontally with respect to the vertical plane, and the inclination may be any angle of 0° to 180°.

(Examples: 30°, 45 °, 60°, 90°, 135 °, 120°, 150°, etc.), (a), (b), (c) in Figure 6 illustrate this situation. The first chamfer 8, the second chamfer 10, the third chamfer 12, the fourth chamfer 14, the fifth chamfer 16 or the sixth chamfer 18 may be a right angle, an acute angle, an obtuse angle, a flat angle, an arc, a polygon or the like. Figures 7(a), (b), (c), (d), (e) exemplify this situation.

The combination of the lateral edges, vertical edges and different shape angles of the various inclinations can produce a plurality of differently shaped threads, Figures 8(a), (b), (c), (d), (e), ( f) List some of the possible combinations. The shape of the external thread 4 on the corresponding nut 3 is adjusted accordingly, and is fully engaged with the internal thread 2 of the screw tail 1, Fig. 9(a), (; b), (; c), (; d), ( ; e), (; f) lists some of the possible combinations. Users can design different thread shapes according to different performance needs and processing capabilities.

Claims

Rights request

A locking thread for a pedicle screw tail, characterized in that the locking thread has an L-shaped cross section.

2. The locking thread according to claim 1, wherein the L-shaped cross section comprises a first corner (8), a first lateral edge (9), a second polygonal corner (10), and a second vertical edge (10). 11), third chamfer (12), second lateral side (13), fourth chamfer (14), third vertical side (15), fifth chamfer (16), third horizontal side (17) and sixth Angle (18), with the vertical placement of the pedicle screw as reference, the inclination of the second vertical edge (11) and the third vertical edge (15) to the horizontal plane is >0° and <180°, the first lateral edge (9) ), the inclination angle of the second lateral edge (13) and the third lateral edge (17) with the vertical plane is >0° and <180. .

3. The locking thread according to claim 2, wherein the third angle (12) is ^0 degrees and ^180 degrees, and when the third angle (12) is 0 degrees, the second lateral side (11) and the The two vertical sides (13) coincide in a straight line.

4. The locking thread according to claim 2, characterized by: a first chamfer (8), a second chamfer (10), a third chamfer (12), a fourth chamfer (14), and a fifth chamfer (16) And the sixth angle (18) is one of a right angle, an acute angle, an obtuse angle, a flat angle, an arc or a polygon.

5. The locking thread of claim 1 wherein the locking thread profile further has another L-shaped cross-section that is symmetric with the L-shaped section to form a T-shaped cross-section.

A pedicle screw having an internal thread at a tail thereof, characterized in that the internal thread is a locking thread according to any one of claims 1 to 5.

A nut (3) having an external thread (4) complementary to an internal thread according to claim 6, wherein the external thread (4) of the nut (3) is screwed into the vertebra After the internal thread (2) of the shank screw tail, the internal thread (2) of the pedicle screw tail (1) and the external thread (4) of the nut (3) are closely fitted to each other.