CN211023033U

CN211023033U - Low-incisura flexible constraint type pedicle screw with laterally arranged rod

Info

Publication number: CN211023033U
Application number: CN201920854766.4U
Authority: CN
Inventors: 何静; 何伟义
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-06-08
Filing date: 2019-06-08
Publication date: 2020-07-17
Anticipated expiration: 2029-06-08

Abstract

The utility model relates to an implant used in orthopedic surgery and neurosurgery, in particular to a low-incisura flexible constraint pedicle screw with an anti-explosion wire function and a side rod; the pedicle screw with the connecting rod arranged on one side of the screw seat has the advantages that the pedicle screw which is difficult to explode for many years is fundamentally solved, the lower incisional track is provided, the constraint force is in a gradual form in the process of flexibly constraining the screw body until the two forms of dynamic screws and fixed screws are switched, the deviation which possibly occurs when two adjacent pedicle screws are expanded or clamped in the operation process is solved, and the trouble of stock is also reduced.

Description

Low-incisura flexible constraint type pedicle screw with laterally arranged rod

Technical Field

The utility model relates to an implant that uses in being applied to bone surgery and neurosurgery, it is theoretical exactly to accord with "non-fixed fusion", can prevent to explode the flexible restraint formula pedicle of vertebral arch nail of a side low notch of putting stick of silk.

Background

At present, in the field of bone surgery and neurosurgery, the traditional scheme for treating herniated disk and spinal stenosis is a pedicle screw which is matched and used according to the 'rigid fixation fusion' theory called 'golden law', and comprises a single-shaft screw and a universal screw which are both called 'fixation screws'; with the development of clinical medicine, a new academic genre, namely a 'non-fusion fixation' theory is derived, and the pedicle screws conforming to the theory gradually accepted by the operative field are called 'dynamic screws'; the main differences between these two different types of pedicle screws (hereinafter referred to as screws) are: after the operation is finished, the whole pedicle screw with the function of the fixing screw and the lesion vertebral body implanted by the screw body are connected into a rigid body; the vertebral pedicle screw with the dynamic screw function can still slightly swing relative to the screw seat and the connecting rod when a diseased vertebral body implanted by the screw body is implanted into the vertebral pedicle screw, so that the stress concentration of adjacent segments can be reduced while the vertebral pedicle screw supports and protects the vertebral column, and the occurrence and extension of the degeneration of the adjacent segments are reduced.

Because the fixed nail and the dynamic nail respectively have the advantages, the two types of nails are often used in the same operation clinically, namely the operation is called as mixed match, so the two types of nails are required to be prepared for standby on site at the same time, and the difficulty of stock is increased clinically.

In addition, in the two types of nails, in the conventional method, a U-shaped open through groove is basically arranged right above the axial lead of a nail seat, an internal thread matched with a screw plug is also arranged at the opening of the open through groove, and the screw plug needs to fix a connecting rod in the open through groove by enough pressing force; although a new process is adopted in recent years, in which the thread form of the screw plug is set to a negative angle to minimize the lateral component force generated by the screw plug, this problem cannot be solved fundamentally, and medical accidents such as operation failure caused by the dropping of the connecting rod due to the loosening of the screw plug sometimes occur.

Due to the component composition characteristics of the structure, the incisional marks (the term in the art, which can be generally approximately considered as the height of the nail seat) are generally between 16 and 19mm, namely: the incision is too high, which increases discomfort such as pain caused by the stimulation of the implant to the muscle.

In addition, in the operation process, one procedure is to prop open the adjacent pedicle screws, fill the adjacent pedicle screws into the CAGE, clamp the pedicle screws and finally lock the connecting rod by using the screw plug; the single-shaft nail is easy to operate in a fixed nail, but due to the characteristics of field operation and human spine, the clamping tool only acts on the nail seat, the tail of the dynamic nail can swing relative to the nail seat, and the tail of the dynamic nail is difficult to keep vertical to the nail seat under the influence of CAGE in the clamping process, so that the function and the characteristic of the dynamic nail are influenced.

How to fundamentally eliminate the important factor of 'wire explosion' which causes the operation failure, simultaneously, the 'incisura' is reduced as much as possible, the mutual conversion of 'fixed nails' and 'dynamic nails' can be realized, and the 'dynamic nails' can be conveniently and correctly locked in the operation, which is a difficult problem which needs to be solved urgently in clinic.

Disclosure of Invention

To the industry in the urgent four difficult problems of "explosion-proof silk", "fall the notch", "interchangeable" and "easily lock" that need solve clinically of pedicle of vertebral arch nail the utility model discloses in the technical scheme, all obtain effectual solution: the connecting rod is arranged in a side-mounted position, namely, the connecting rod occupying the notch is arranged on one side of the nail seat instead of being arranged in the middle above the axis of the nail seat in the traditional way, so that a considerable space is left for reducing the notch.

And because the connecting rod is arranged at one side and forms a screw seat of the screw pair with the screw plug, the traditional U-shaped open slot structure can be improved into an encircling shape, so that the phenomenon of 'wire explosion' caused by the fact that the open through slot with a relatively weak structure is 'outwards expanded' by the lateral external force of the screw plug is fundamentally solved.

Because the connective bar is arranged in one side, the control of separation plug screw to the nail body no longer, this is just for setting up a control screw again in the middle of the plug screw and be used for forming for probably to the selective control of the bulb on the nail body, just this kind of possibility just makes the utility model discloses a pedicle screw has the function of "interchangeable" to only need be equipped with a money nail, just can satisfy and have required "thoughtlessly taking" clinically, just also solved the stock problem.

By using the function of switching the dynamic nail into the fixed nail in the operation, two adjacent nails can be easily spread or clamped by using a common tool to keep the vertical of the nail body and the nail seat; just so, the utility model discloses a technical scheme can solve four difficult problems that need solve in the clinical urgent need well.

Furthermore, the outer surface of the upper half part of the nail seat is provided with a taper matched with the inner wall of the hook frame, and the inner cavity of the nail seat is provided with an internal thread matched with the screw plug; the lower half part of the connecting rod is a cylinder with a round chamfer on the outer surface, a groove for assisting in clamping the connecting rod is arranged on one side of the outer surface of the lower half part, and a lower opening of a hemispherical surface is arranged at the downward end of the inner cavity.

Furthermore, the screw plug is provided with an internal thread and an external thread which are respectively matched with a control screw which is used for controlling the head of the screw body and an internal thread in the inner cavity of the screw seat; the flat upper cover that the plug screw top outwards extended, its center has the recess that supplies the screwdriver to use, can compress tightly the hook frame that cup joints on the nail seat, and the downward face of plug screw processes the inner chamber of an indent.

Still further, in the inner cavity, a group of fittings, a control block which is cylindrical and flat, a spring with a wire distance slightly larger than the wire diameter and a pressing block which is in the shape of a ring column and is downwards opened to be matched with the ball head of the nail body are assembled.

Furthermore, the hook frame is a tubular body with a tapered inner wall, and the inner wall of the hook frame is matched with the outer surface of the nail seat; a notch is arranged on one side of the tubular body, a press rod arm extends outwards above the notch, the press rod arm is provided with a U-shaped groove with a downward opening, and the clamp rod groove on the outer side of the nail seat exposed out of the notch and the U-shaped groove on the press rod arm jointly clamp and fix the connecting rod.

Furthermore, the connecting rod is a cylindrical rod, and a universal part on the traditional pedicle screw is used, so that the research and development cost is saved; the nail body basically adopts a universal part, the lower half section, namely the tail part, of the nail body is a nail-shaped body with external threads, and the nail-shaped body extends out of the lower opening of the nail seat and is implanted into the vertebral body of a patient; the upper half section of the nail body, namely the head part, is a spherical body and is provided with a plane vertical to the axis of the tail part, the center of the plane is provided with a blind hole matched with the screwdriver, and a semicircular pit is arranged in the blind hole.

Still further, the control screw is a standard component, is arranged in the internal thread in the center of the screw plug and is used for controlling the control block, the spring and the pressing block, so that the flexible restraining force of the pedicle screw is gradually increased until the dynamic screw is switched into the fixed screw.

Advantageous effects

The utility model has the advantages that the difficult problem of 'wire explosion' which troubles clinical practice for many years is fundamentally solved; meanwhile, enough space is provided for reducing 'notch'; in addition, the switching between the two states can be realized, so that the clinical 'mixed matching' stock problem can be met only by equipping one nail; and because the switching can be carried out at any time, the operation of clamping and loosening the nail in the operation can be more favorably adjusted, thereby fully exerting the inherent advantages of the dynamic nail.

To sum up, the utility model discloses novelty and creativity have to, four difficult problems that face clinically that can solve, consequently, have stronger practicality, and can produce very big social.

Drawings

The invention is further explained below with reference to the drawings and the embodiments;

Fig. 1 is a two-dimensional diagram and an effect diagram of the present invention;

Fig. 2 is an exploded schematic view of the main components of the present invention;

FIG. 3 is an exploded view of a portion of the present invention;

Fig. 4 is a schematic diagram illustrating the switching between two states of the present invention;

FIG. 5 is a schematic diagram of the principle of "wire explosion" and "notch" that the present invention can solve;

FIG. 6 is a schematic diagram of the "lock" and "interchange" concept that can be solved by the present invention;

Wherein: a plug screw 1; a hook frame 2; a connecting rod 3; a nail body 4; a nail seat 5; a control screw 6; a spring 7;

A control block 8; pressing blocks 9; (tool-holder G;)

A plug screw external thread 11; a plug screw inner screw hole 12; a screw upper cover 13; a plug screw cavity 14;

A hook frame inner wall 21; a hook frame notch 22; a hook frame pressing bar arm 23; a plunger slot 24;

A nail body head 41; a nail body tail 42;

A nail seat outer conical surface 51; nail seat internal threads 52; nail holder clamping bar grooves 53; a staple holder lower opening 54;

Pressing block inner spherical surface 91; and a compact end face 92.

Detailed Description

In order to understand the utility model more easily, the following four problems are introduced to be solved clinically: as shown in the right effect drawing of fig. 5, the conventional pedicle screw basically utilizes the screw thread on the open through groove to press the connecting rod downwards into the U-shaped open through groove of the screw seat by the screw plug so as to achieve the connection of the adjacent screws; the larger the downward acting force of the screw plug on the connecting rod is, the larger the generated lateral component force F on the nail seat is, the deformation is generated at the upper end of the opening through groove on the weaker nail seat, and when the opening through groove is expanded outwards to a certain degree, the matching of the thread pair is weakened and even fails, which troubles the phenomenon of 'wire explosion' for years in the technical field; in addition, in the middle of fig. 5, what is shown is the two-dimensional map of traditional pedicle screw, and its connective bar 3 and plug screw 1 are placed in the middle, have certainly taken certain height, and the left side is shown the utility model discloses a two-dimensional map, connective bar 3 be moved to one side, vacate the ascending space of direction of height effectively, the notch height h that reduces reaches 6~9 mm.

In addition, as shown in fig. 6, the dynamic nail has the function of "promoting fusion in micro-dynamic state", and after the operation is completed, the tail 42 of the nail body, together with the implanted vertebral body, still can swing in positive and negative directions relative to the connecting rod 3 and the nail seat 5 which are fixed into a whole, as shown in the nail on the left side of fig. 6; in the operation process, when the screw plug 1 is not locked, the clamping tool G must be used to firstly spread the adjacent nails and place the adjacent nails into a support called CAGE (shown in the middle of fig. 6), because the action point of the clamping tool G is on the nail seat 5, and the nail body 4 can swing relative to the nail seat 5, when the adjacent nails are clamped and the screw plug 1 is locked, as shown on the right side, the swing angle of the dynamic nail which can display the dynamic function is lost by half, and even more, reaches the limit angle, which affects the effective function of the dynamic nail; therefore, if the nail body 4 and the nail seat 5 of the pedicle nail can be kept coaxial in the expanding or clamping process and are in a single-axis nail state, the situation shown on the right side of the figure 6 can be effectively avoided.

The utility model adopts the technical proposal that: the connecting rod 3 is arranged in a side-mounted mode, so that the structural form of the nail seat 5 which is easy to generate 'wire explosion' and is provided with a U-shaped open slot is fundamentally eliminated, and the specific improvement points of the connecting rod are explained in the following.

As can be seen from the two-dimensional diagrams and the exploded diagrams of the present invention shown in fig. 1 and 2, the outer conical surface 51 of the nail seat in the upper half of the nail seat 5 has a taper, and is matched with the inner wall 21 of the hook frame 2; the inner cavity is a cavity provided with internal threads 52 and is matched with the external threads 11 of the screw plug 1, so that the hook frame 2 sleeved on the nail seat 5 is locked and fixed; therefore, the structural form of the U-shaped open slot is cancelled, and the thread pair matched with the screw plug 1 can be made into an encircling shape instead of the traditional open U-shaped slot, so that the phenomenon of 'wire explosion' is fundamentally solved; in addition, the thread pair consisting of the external thread 11 and the internal thread 52 of the nail seat does not need to adopt a negative chamfer thread with larger processing difficulty, but can adopt a common triangular tooth form which is extremely easy to process, thereby greatly reducing the processing cost.

The hook frame 2 is a hollow cylinder, a gap 22 is arranged in order to conveniently and jointly fix the connecting rod 4, the gap is accurately exposed out of a nail seat clamping rod groove 53 on the nail seat 5, a pressing rod arm 23 extends outwards from the corresponding upper part of the gap 22 of the hook frame, and the inner wall 21 with taper can be accurately superposed with the axis of the matched nail seat 5, so that the hook frame can be accurately positioned and combined with the downward opening pressing rod groove 24 of the pressing rod arm 23 and the nail seat clamping rod groove 53 to jointly lock the connecting rod 3; in the research and development process, the set taper is 10 degrees, so that the purpose of accurate positioning of the original design can be achieved.

The screw plug 1 is a screw, the center of the screw plug is provided with an inner screw hole 12 matched with the control screw 6, the top end of the screw plug 1 is provided with a screw plug upper cover 13, the center of the screw plug 1 is provided with a slotted hole for a screw driver, and a tool is used for pressing the hook frame 2 by utilizing the screw plug upper cover 13 so as to lock the connecting rod 3; the control screw 6, in the present development, is provided as a flat bottom screw M4.

Nail body bulb 41 is restrained the lower extreme of nail seat inner chamber, its can swing the angle and be restricted in the diameter of the downward opening 54 of nail seat 5 to can be according to the requirement of different academic genres in clinic, and the concrete specification of the nail body 4 that uses of cooperation is different, sets up to 6.3~6.8mm, can realize + (2 ~10 °) swing angle.

Before clinical application, the nail body 4 is assembled in the nail seat 5 and is set to be incapable of being separated, and during clinical application, the nail body 4 can be implanted into a diseased vertebral body only by using a screwdriver and then is placed into the hook frame 2, and then the connecting rod 3 is placed into the rod pressing groove 24 of the hook frame 2 of an adjacent nail to realize connection; because the hook frame inner wall 21 and the nail seat outer conical surface 51 are in conical fit, the rod pressing groove 24 on the hook frame 2 is in a half-circumference arc surface, and can be automatically or slightly adjusted to be overlapped with the arc surface on the rod clamping groove 53 on the nail seat and the axial lead formed by the rod pressing groove and the nail seat outer conical surface, after the screw plug 1 is screwed into the nail seat inner wall 21 and locked, the screw plug upper cover 13 presses the hook frame 2, so that the two arc surfaces of the rod clamping groove 53 and the rod pressing groove 24 jointly contain the circumference of the connecting rod 3 by about 250 degrees, which is enough to restrain and lock the connecting rod 3, so that the screw plug 1, the hook frame 2, the connecting rod 3 and the nail seat 5 are connected into a whole, and the nail body ball 41 can swing at a certain angle around the ball center of the inner cavity of the nail seat 5, and the function of a dynamic nail is presented in this state.

In order to meet the clinical high-end clinical effect, the utility model can generate micro-play along the axial direction (Z axis) of the nail body, thereby fully applying the theory of 'micro-dynamic promotion and fusion' of the function of the dynamic nail; as shown in fig. 3; the downward surface of the screw plug 1 is provided with an inwards concave cylindrical cavity 14, the flat control block 8 and a spring 7 (commonly called a sparse spring) with the wire distance slightly larger than the wire diameter are both arranged in the cavity 14, and the pressing block 9 is arranged above the nail body ball 41; when the screw plug 1 is locked, the control block 8 is upwards pushed to the top surface of the inner cavity tightly attached to the screw plug 1 under the action of the spring 7, the end surface 92 of the pressing block 9 is downwards pressed, and the inner spherical surface 91 of the pressing block is pressed against the nail body ball head 41 to be flexibly constrained; the restraining force is determined by the elastic force presented by the wire diameter used for manufacturing the spring 7; in this state, as shown in the left side of the center line of the two-dimensional drawing of fig. 1 and the left side effect drawing of fig. 4, the whole nail has the function of a "dynamic nail", and when the nail is impacted along the axial direction (Z direction) of the nail body, the spring 7 can play a role in damping, so that the nail body 4 and the implanted vertebral body can play a slight amount of movement in the Z direction, and the function of the "dynamic nail" is fully embodied.

If the control screw 6 passes through the screw plug inner screw hole 12 and downwards presses the control block 8, the height of the spring 7 is changed, the presented elastic force is changed, and then the generated flexible constraint force of the press block inner spherical surface 91 on the screw body ball head 41 is also changed, so that the requirements of different swinging force couples realized by clinically arranging and adjusting the control screw 6 can be met; once the above-mentioned control screw 6 is adjusted to the limit degree, the coils of the spring 7 are pressed to the limit degree by the control block 8, and deformed into the state of "dense spring", that is, the coils are pressed close to each other, and the pressing block 9 is pressed downwards, and finally the ball 41 on the nail body is pressed by the downward cambered surface thereof, so as to realize the switching to the "fixed nail", which is the state shown on the right side of the central line of the two-dimensional diagram of fig. 1 and the right side of the effect diagram of fig. 4.

In summary, the technical proposal provided by the utility model can solve the technical problems of easy wire explosion, high cutting trace, troublesome stock and difficult locking, etc. which are puzzled in the clinical world for years, and the key core technical measure adopted, namely the side bar, is creative; the conception is extremely novel; in clinical effect, the utility model is more practical; moreover, the above embodiments are not intended to be exhaustive or to limit the present invention to the precise embodiments disclosed, and therefore, any modifications, equivalents, improvements, etc. made by using the contents of the specification and drawings should be included in the scope of the present invention.

Claims

1. The utility model provides a low notch flexible restraint formula pedicle of vertebral arch nail of stick is put to side, by plug screw, hook frame, connective bar, the nail body, nail seat and by control screw, control block, spring and the control assembly that the briquetting constitutes, its characterized in that:

The screw plug is provided with internal and external threads which are respectively matched with the control screw and the inner cavity of the nail seat, a flat upper cover extends out of the top end of the screw plug and is used for pressing the hook frame sleeved on the nail seat, the center of the upper cover is also provided with a groove for a screwdriver, and the downward end surface of the screw plug is an inwards concave cylindrical blind hole and is used for assembling the control component for implementing reversible control on the nail body;

The hook frame is a tubular body with a tapered inner wall, one side of the hook frame is provided with a notch, a rod pressing arm extends outwards above the notch, and the rod pressing arm is provided with a U-shaped groove with a downward opening and used for clamping and fixing the connecting rod;

The outer surface of the upper half section of the nail seat is provided with a taper matched with the inner wall of the hook frame, and the inner cavity of the nail seat is provided with an internal thread matched with the screw plug; the lower half section of the connecting rod is a cylinder with a round chamfer on the outer surface and is provided with a groove for assisting in clamping the connecting rod, and the downward end of the inner cavity is provided with a lower opening of a hemispherical surface.

2. The low-notch flexible constrained pedicle screw for a lateral rod according to claim 1, wherein: the control assembly, by four gadgets constitute, include: a control screw with external threads; a flat cylindrical control block, a cylindrical spring with a wire distance larger than the wire diameter; and a pressing block which is in an annular column shape and is provided with an incomplete spherical surface downwards.

3. The low-notch flexible constrained pedicle screw for a lateral rod according to claim 2, wherein: the control screw in the control assembly is matched with the internal thread in the center of the screw plug to adjust the control block, the associated cylindrical spring and the associated pressing block up and down, so that the flexible constraint on the nail body is implemented until the nail body can move relative to the nail seat or not is controlled, and the reversible switching between the dynamic nail and the fixed nail is realized.

4. The low-notch flexible constrained pedicle screw for a lateral rod according to claim 2, wherein: the lower half section of the nail body is a nail body with external threads, extends out of the downward opening of the nail seat and is implanted into the vertebral body of a patient; the upper half section is a spherical body matched with the downward surface of the pressing block, a plane vertical to the axis of the nail body is processed, and the center of the plane is provided with a groove for a screwdriver.

5. The low-notch flexible constrained pedicle screw for a lateral rod according to claim 1, wherein: the spherical body at the upper half section of the nail body is flexibly constrained by the pressing block arranged above the spherical body, the spherical body swings around the spherical center of the spherical body in the inner cavity of the nail body, and the swinging angle of the spherical body is constrained by the diameter of the lower opening of the nail seat.

6. The low-notch flexible constrained pedicle screw for a lateral rod according to claim 1, wherein: the control screw in the control assembly can be selectively placed or not, so that reversible function switching of the whole pedicle screw can be realized; and the adjustment and control of the swing couple presented by the whole pedicle screw are realized by adjusting the depth of the implantation.

7. The low-notch flexible constrained pedicle screw for a lateral rod according to claim 1, wherein: the main body of the connecting rod is cylindrical and is used for connecting adjacent pedicle screws; can be properly bent and adjusted during the operation, and the two ends of the surgical instrument are processed with modifications which are convenient for placement or clamping.