JP3608943B2 - Spinal fixation hook - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a spinal fixation hook used exclusively in a spinal device of a surgical implant that connects and fixes a deformed or degenerated spine of a spine for correction.
[0002]
[Prior art]
Conventional spinal devices are used to correct a spine under a disease such as scoliosis or kyphosis by surgery, and members such as wires, screws, hooks, etc. can be placed either on the front, side or back of the vertebral bone. The fixed member was connected to each other by a rod or a plate.
[0003]
In the spinal device, a hook is often used as a member to be fixed to the vertebral bone. As illustrated in FIG. 6, the hook 25 is fixed to several places of the spinous process 23 and the lateral process 22 of the vertebral bone. The rods 24 and 24 are connected and fixed to these hooks 25 to correct the spine. As shown in FIG. 7, the hook 25 used in this case has one hook portion 26 for hooking to the vertebral bone, and one hook portion 25 is usually used for one fixing point. There are many so-called single hook systems that use the hook 25, but even though this is good in terms of compactness, operability, and hook strength, it is in the shape of a needle, so the reverse direction on the open side When a load is applied, there is a possibility that the fixing property is removed from the inferior place.
[0004]
In order to solve the problems of the single hook method, a single hook combined method using two hooks 27 for one fixed portion as shown in FIG. 8 has been conventionally employed. Since this is a fixing method in which the hook 27 is clamped from both sides, there is an advantage that strong fixing can be obtained. However, since the two are used, adjustment of the respective installation positions is complicated, and the operation (correction) time is lengthened. Further, since the shape is increased, there is a problem that the burden on the patient is increased.
[0005]
On the other hand, as a technique capable of improving the single hook method and the single hook combined method, there is provided a prior art in which two hooks are combined into one hook 28 and made compact, for example, Japanese Patent Laid-Open No. 9-285473. It is also disclosed in the Gazette. As shown in FIG. 9, this is a structure in which one hook 29 and the other hook 30 are connected by a screw 31 and integrated. In this prior art, the fixing width can be easily adjusted by adjusting the screw 31. However, the adjustment operation is complicated and the operation time may be prolonged, and the screw diameter is small, so that breakage or loosening is likely to occur after fixing. Is fully expected.
[0006]
[Problems to be solved by the invention]
As described above, each of the conventional spinal fixation hooks has advantages and disadvantages, and the appearance of a spinal fixation hook that can satisfy all of the fixation to the vertebra, the attachment / detachment operability, and the compactness is demanded in view. Is the actual situation.
[0007]
The present invention has been made to solve such problems, and the object of the present invention is to satisfy all of fixation to the vertebra, detachability, compactness and robustness. An object of the present invention is to provide a spinal fixation hook that can contribute to shortening the operation time, facilitating the appropriate size determination, and reducing the burden on the patient.
[0008]
[Means for Solving the Problems]
The present invention has the following configuration in order to achieve the above object. That is, the invention according to claim 1 of the present invention includes a hook mechanism 2 that is sandwiched and engaged with a transverse process 22 of a vertebra from both sides by a pair of hooks 8 and 11 hinged so as to be openable and closable, and a hinge shaft. A lock mechanism 3 that is formed integrally with the pair of flanges 8 and 11 at a position opposite to the hook mechanism 2 with the pin 7 interposed therebetween, and that releasably locks the pinched state in conjunction with the opening and closing operation of the hook mechanism 2; A rod fixing mechanism 4 that is integrally formed with one of the heel portions 8 of the mechanism 2 and engages with a spinal correction rod 24 at a rear position of the hook mechanism 2 to hold and fix the rod 24 behind the vertebra. It is the spinal fixation hook 1 characterized by these.
[0009]
The invention of claim 2 of the present invention comprises two hook members 5 and 6 hinged at the intermediate portion, and one hook member 5 is a pair of hook mechanisms 2 for holding the transverse process 22 of the vertebrae and the like. A rod fixing mechanism 4 that engages with the heel portion 8 as a member and a rod 24 for correcting the spine and holds and fixes the rod 24 behind the vertebra is fixed to the front portion and the rear portion on one side of the hinge shaft 7. An abutting piece 9 is provided on the other side and has a contact surface 10 parallel to the hinge shaft 7 on the rear side, and the other hook member 6 has a hook 11 as a counter member of the hook mechanism 2 hinged. A contact piece 12 provided on one side of the shaft 7 and having a contact plane 13 parallel to the hinge shaft 7 on the front surface is provided on the other side, and the contact planes 10 and 13 facing each other. Lock them when they touch each other The lock mechanism 3 is provided in association with the two abutting pieces 9 and 12, and is formed so that the lock mechanism 3 can hold the pair of flange portions 8 and 11 in the clamping state by operating to the closing side. The spinal fixation hook 1 is characterized by being made.
[0010]
The invention of claim 3 in the present invention relates to the invention of claim 2, wherein the lock mechanism 3 extends in parallel to the hinge shaft 7 at the end farthest from the hinge shaft 7 of one abutting piece 12. And a protruding strip provided so as to be able to engage with the flange 14 extending parallel to the hinge shaft 7 at the end farthest from the hinge shaft 7 of the other abutting piece 9. 15 is a spinal fixation hook 1 characterized by comprising:
[0011]
Further, the invention of claim 4 in the present invention relates to the invention of claim 2 or 3, wherein the rod fixing mechanism 4 includes a rod housing portion 16 having a substantially Ω-shaped cross section in a direction perpendicular to the hinge shaft 7; The rod housing portion 16 includes a rod insertion groove 18 that extends in a direction perpendicular to the hinge shaft 7 and that opens to the rear end surface side. Is characterized in that it is formed on a slide lid that can slide in a direction parallel to the rod insertion groove 18 and can be fitted into the rod accommodating portion 16.
[0012]
The invention of claim 5 in the present invention relates to the invention of claim 2, 3, or 4, wherein one abutting piece 12 is provided with a hole 19 for inserting a locking screw, and the other abutting piece 9. A screw hole 20 into which the screw is screwed is provided to enable locking by screw tightening in addition to the lock mechanism 3.
[0013]
The invention of claim 6 in the present invention relates to the invention of claim 2, 3, 4 or 5, wherein the vertebral correction rod fixed and held by the rod fixing mechanism is based on the pinching point by the hook mechanism. It is characterized by being formed so as to be fixed with an inclination within a range of ± 45 ° with respect to the lateral protrusion or the like.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 4 of the accompanying drawings. FIG. 1 is a perspective view in an open state of a spinal fixation hook 1 according to an embodiment of the present invention, FIG. 2 is a perspective view in the same closed state, and (a) in FIG. 3 is an embodiment of the present invention. FIG. 4 is a plan view of the spinal fixation hook 1 according to FIG. 4, (B) is also a front view, (C) is a right side view, (D) is also a left side view, and (A) in FIG. (B) is also a front view, (c) is a plan view of the lid material for the spinal fixation hook 1 shown in FIG. 3, and (b) is also a front view. is there.
[0015]
The spinal fixation hook 1 shown in FIG. 1 to FIG. 3 is manufactured in a predetermined shape with each component member including a main body portion made of a biological metal such as titanium containing a titanium alloy. In addition, biological stainless steel and cobalt-chromium alloy are also used. This spinal fixation hook 1 is composed of two hook members 5 and 6, and the shaft shafts provided at the intermediate portions thereof are combined so that the hinge shaft 7 is inserted in a non-removable manner by “caulking” processing or the like. The hook members 5 and 6 are hinged so as to be openable and closable so that both side portions of the hinge shaft 7 are contacted and separated.
[0016]
In the spinal fixation hook 1 having such a configuration, the hook mechanism 2 and the rod fixation mechanism 4 are formed in a front-rear positional relationship on one side of the hinge shaft 7, and the lock mechanism 3 is formed on the opposite side. . In addition, regarding the positional relationship between the hook mechanism 2 and the rod fixing mechanism 4, in this specification, for convenience, the side closer to the side to be clamped is separated from the front side and the lateral process 22 with respect to the lateral process 22 of the target vertebra. The far side is called the rear side, and it is written “front and back” accordingly. A specific structure of the spinal fixation hook 1 will be described below.
[0017]
Both hook members 5 and 6 are short-shaped molded members whose width in the direction of the hinge shaft 7 is about 10 mm at the maximum, and one hook member 5 is hooked on one side with the hinge shaft 7 in between. A flange portion 8 as a counter member of the mechanism 2 and a rod accommodating portion 16 as a main body portion of the rod fixing mechanism 4 are provided, and a contact piece portion 9 is provided on the other side. The other hook member 6 includes a flange portion 11 as a pair member of the hook mechanism 2 on one side with the hinge shaft 7 interposed therebetween, and a contact piece portion 12 on the other side. The flange portion 8 is a flange member on the receiving side having a short semicircular arc surface having a substantially semicircular arc shape as a sandwiching surface, and the flange portion 11 which is in contrast to this is narrower than the flange portion 8. It is a collar member on the movable side having a shape similar to that of the collar.
[0018]
On the other hand, the abutting piece portion 9 is formed in a plate piece having a half width of the flange portion 8 extending straight from the shaft hole portion through which the hinge shaft 7 is inserted to the opposite side of the flange portion 8. A parallel contact plane 10 is provided on the rear surface (the surface on the side facing the abutting piece 12). The abutting piece portion 12 which forms a pair with the abutting piece portion 9 is bent from the shaft hole portion through which the hinge shaft 7 is inserted to the opposite side of the collar portion 11 at an angle of about 90 °, and the like. It is formed in the board piece with a width | variety, and has the contact plane 13 parallel to the hinge axis | shaft 7 in a rear surface (surface of the side facing the contact plane 10). In this embodiment, the abutting piece portion 9 is provided with a screw hole 20 for screwing a locking screw (not shown) in the center portion, while the abutting piece portion 12 has a locking hole. A hole 19 for inserting a screw is provided at a position corresponding to the screw hole 20.
[0019]
Thus, the hook member 5 including the flange portion 8 and the half-width contact piece portion 9 and the half-width flange portion 11 and the contact piece portion 12 are hinge-coupled to each other, so that the opposite flange portion 8 and the flange portion are opposed to each other. 11 is regulated by the abutment portion 9 of the flange 11 closer to the hinge shaft when it is fully opened, and the abutting flat surface 10 of the contact piece 9 and the contact piece 12 when the pin is in the minimum closed state. Therefore, it is possible to set the opening / closing angle of the flanges 8 and 11 within an appropriate range at the time of design.
[0020]
In the hook members 5 and 6 configured as described above, the hook member 5 is provided with the rod fixing mechanism 4, and the lock mechanism 3 is provided in association with the two contact pieces 9 and 12. The rod fixing mechanism 4 is further formed by a rod accommodating portion 16 as a main body portion and a lid member 17 as a slide lid fitted to the rod accommodating portion 16 with reference to FIG.
[0021]
The rod housing portion 16 is provided at a position rearward of the flange portion 8 in the hook member 5 so that a cross-sectional shape in a direction perpendicular to the hinge shaft 7 forms a substantially Ω shape, and in a direction perpendicular to the hinge shaft 7. A rod insertion groove 18 that extends and opens on the rear end face side is recessed. The rod insertion groove 18 has a width corresponding to the diameter of the rod 24 and is recessed in a semi-circular groove so that the rod 24 can be tightly accommodated so that play does not occur. Yes. A dovetail is provided on the outer edge of the opening of the rod receiving portion 16 so as to protrude from both sides.
[0022]
On the other hand, as shown in FIGS. 4C and 4D, the cover member 17 has a lip groove shape in cross section with a dovetail groove that fits into the dovetail portion of the rod housing portion 16. A screw hole is screwed into the central portion of the lid surface portion, and a fixing screw 21 (see FIGS. 4A and 4B) made of a set screw with a hexagonal hole is screwed into the screw hole.
[0023]
In addition, the spinal fixation hook 1 according to the embodiment of the present invention is fixed to the spine fixed to the rod fixing mechanism 4 with reference to the pinching point of the hook mechanism 2 as shown in FIGS. It is preferable that the correction rod is formed so as to be fixable with an inclination within a range of ± 45 ° with respect to the transverse process 22 of the vertebra. In this case, the inclination angle θ as shown in FIG. If there is, it can be fixed low to the vertebrae, so that the protrusion to the back side of the patient is low, which is cosmetically effective and alleviates the patient's pain.
[0024]
Next, the locking mechanism 3 is formed by a flange piece 14 provided integrally with the contact piece portion 12 and a ridge 15 provided integrally with the contact piece portion 9. The flange 14 is provided at the farthest end edge of the hinge shaft 7 so as to be bent in a hook shape from the contact plane 13 toward the contact piece 9 and to extend in parallel to the hinge shaft 7. The ridges 15 are provided at the corners on the side of the abutting plane 10 at the farthest edge of the hinge shaft 7 so as to extend parallel to the hinge shaft 7 and engage with the collar piece 14. When the abutment planes 10 and 13 facing each other are in surface contact with each other, the pair of flanges 8 and 11 are moved to the closed side and are in a sandwiched state. At this time, the tip portion of the hook piece 14 gets over and engages with the ridge 15, and thereby operates to lock the holding state of the hook portions 8 and 11. The engaged scissors 14 and the ridges 15 are engaged using a jig such as a pliers and a screwdriver so as to be mechanically strongly engaged so that they are not easily detached by a hand operation. In order to be able to solve, the shape of the collar piece 14 and the protruding item | line 15 is set appropriately at the time of design.
[0025]
The spinal fixation hook 1 configured as described above is manufactured in advance in various dimensions adapted to the shape and size of the projection of the target vertebra, in which case left and right handed right and left handed left and right It is similar to the conventional spinal fixation hook that a symmetrical one is prepared.
[0026]
An attachment method for correcting, for example, the thoracic vertebra by the spine device using the spinal fixation hook 1 according to the embodiment will be described. The spinal fixation hook 1 in a state in which the locking mechanism 3 is detached and the pair of heel portions 8 and 11 are opened is brought into contact with the vertebrae near the base of the transverse protrusion 22 and sandwiched between the heel portions 8 and 11 to thereby form the transverse process. 22 is engaged and held. This engagement operation can be easily performed using a fingertip or a predetermined jig. By reliably engaging, the flange piece 14 and the ridge 15 are clamped and locked, and this state is firmly held. In addition, when it is desired to change the position or exchange of the spinal fixation hook 1 attached during the operation, it can be easily operated by removing the lock by the collar 14 and the ridge 15, and the ridge 14 and the ridge. Since 15 is in the rear position away from the vertebra, it can be operated easily.
[0027]
The spinal fixation hook 1 is completely fixed by locking the collar piece 14 and the ridge 15, but finally, the abutting pieces 9 and 12 are tightened by using the holes 19 and the screw holes 20. By fixing, further reliable fixing can be achieved. When the necessary number of spine fixation hooks 1 have been fixed, the rod 24 made of a straight or curved round bar that matches the correction shape of the spine is inserted into the rod insertion groove 18 of the rod accommodating portion 16 at the upper end side. Or it is made to insert sequentially from a lower end side, each lid | cover material 17 is each fitted by a slide, and it tightens with the screw 21 for fixing. Thus, the assembly of each spinal fixation hook 1 and the rod 24 is ensured. The wearing state of the spinal device according to the embodiment of the present invention in this case is as shown in FIG.
[0028]
【The invention's effect】
As described above, the present invention is mounted and fixed to the spine by the spinal fixation hook having a hinged structure, so that the mounting can be performed quickly and easily and the operation time is shortened. Moreover, since mechanical locking is performed at the same time by mounting, handling is simple and convenient. Furthermore, since it can be temporarily fixed by the lock mechanism, it can be easily attached and detached any number of times during the operation, which helps to determine an appropriate size. In addition, since there is no adjustment screw that directly affects the mounting adjustment, there is no problem of breakage or looseness, and the reliability and safety are high.
[0029]
As described above, according to the present invention, it is possible to reduce the burden on the subject by facilitating the procedure for surgery and shortening the processing time, and strengthen the fixing force to the vertebra to strengthen the connection of the vertebra. By making it possible, the effectiveness of spinal correction can be improved.
[Brief description of the drawings]
FIG. 1 is a perspective view of a spinal fixation hook according to an embodiment of the present invention in an open state.
FIG. 2 is a perspective view in a closed state corresponding to FIG. 1;
3A is a plan view of a spinal fixation hook according to an embodiment of the present invention, FIG. 3B is a front view, FIG. 3C is a right side view, and FIG. 3D is a left side view. .
4A is a plan view of a set screw related to the spinal fixation hook shown in FIG. 3, FIG. 4B is a front view of the same, and FIG. 4C is a plan view of a lid material related to the spinal fixation hook shown in FIG. (B) is also a front view.
FIG. 5 is a perspective view showing a mounted state of the spinal device according to the embodiment of the present invention.
FIGS. 6A and 6B are explanatory views of an attachment mode of the spinal fixation hook according to the embodiment of the present invention to the vertebrae. FIG. 6A is an example with an inclination angle θ, and FIG. 6B is an example without an inclination angle θ. .
FIG. 7 is an explanatory view of a conventional spinal device.
FIG. 8 is a perspective view of a first example of a conventional spinal fixation hook.
FIG. 9 is a perspective view of a second example of a conventional spinal fixation hook.
FIG. 10 is a perspective view of a third example of a conventional spinal fixation hook.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Spinal fixation hook 2 ... Hook mechanism 3 ... Lock mechanism 4 ... Rod fixing mechanism 5 ... Hook member 6 ... Hook member 7 ... Hinge shaft 8 ... Gutter part 9 ... Contact piece part 10 ... Contact plane 11 ... Gutter part 12 ... Abutting piece 13 ... abutting plane 14 ... flange 15 ... ridge 16 ... rod housing part 17 ... lid material 18 ... rod insertion groove 19 ... hole 20 ... screw hole 21 ... fixing screw 22 ... lateral protrusion 23 ... Spinous process 24 ... Rod 25 ... Hook 26 ... Buttocks 27 ... Hook 28 ... Hook 29 ... Buttocks 30 ... Buttocks 31 ... Screw

Claims (6)

A hook mechanism that is clamped and engaged with a lateral process of the vertebra from both sides by a pair of hooks that are hinged to be openable and closable, and a pair of hooks that are on the opposite side of the hook mechanism with the hinge shaft in between And a lock mechanism that releasably locks the clamping state in conjunction with the opening / closing operation of the hook mechanism, and is formed integrally with one hook portion of the hook mechanism, and the spine is corrected at a rear position of the hook mechanism. A spinal fixation hook comprising: a rod fixing mechanism that engages with a rod for use in holding and fixing the rod to the back of the vertebra. It consists of two hook members hinged at the middle part, and one hook member engages with the buttock as a pair member of the hook mechanism that holds the transverse process of the vertebrae, etc. A rod fixing mechanism for holding and fixing to the rear of the vertebrae is provided at the front and rear portions on one side of the hinge shaft, and a contact piece portion having a contact plane parallel to the hinge shaft on the rear surface is provided on the other side. The other hook member is provided with a hook portion as a counter member of the hook mechanism provided on one side with the hinge shaft interposed therebetween, and an abutting piece portion having a contact plane parallel to the hinge shaft on the front surface. In addition, a locking mechanism is provided in association with the two abutting pieces when the abutting planes facing each other come into surface contact with each other, and the pair of hooks are closed. Acting on the growth side and not holding Spinal hooks, characterized in that formed by as formed capable of holding the by the locking mechanism. A locking mechanism is provided at the end farthest from the hinge axis of one abutment piece and extending parallel to the hinge axis, and at the end farthest from the hinge axis of the other abutment part The spinal fixation hook according to claim 2, comprising a ridge that extends in parallel with the hinge shaft and that can be engaged with the flange. The rod fixing mechanism includes a rod housing portion having a substantially Ω-shaped cross section perpendicular to the hinge shaft, and a lid material fitted to the rod housing portion, and the rod housing portion is perpendicular to the hinge shaft. And a cover member is formed in a slide cover that can slide in a direction parallel to the rod insertion groove and fit into the rod receiving portion. The spinal fixation hook according to claim 2 or 3 to be performed. A hole through which a locking screw is inserted is provided in one abutting piece, and a screw hole for screwing the screw is provided in the other abutting piece, enabling locking by screw tightening in addition to the locking mechanism. Item 5. A spinal fixation hook according to item 2, 3 or 4. The spinal correction rod fixed and held by the rod fixing mechanism with respect to the pinching point by the hook mechanism is formed so as to be fixable with an inclination within a range of ± 45 ° with respect to the transverse process of the vertebra and the like. The spinal fixation hook according to 4 or 5.

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