CN209847348U - Pedicle screw and rod structure - Google Patents

Abstract

A pedicle screw rod structure belongs to the technical field of medical instruments. Including screw body, nail stick and locking screw, there is the screw base on the upper portion of screw body, and the screw base constitutes there is screw base U word chamber, constitutes there is the internal thread on the chamber wall in screw base U word chamber, and the nail stick is put into screw base U word intracavity and is supported in the bottom in screw base U word chamber, locking screw be located screw base U word intracavity and this locking screw with the internal thread is joined in marriage soon, will follow closely the stick by locking screw and screw body fixed connection in the position that corresponds to screw base U word chamber, characteristics: a nail rod milling plane is formed on the surface of the nail rod and along the length direction of the nail rod, the cross section of the nail rod is made to be in a D shape by the nail rod milling plane, and the locking screw is in contact with the nail rod milling plane. Has the ability of resisting rotation and longitudinal extrusion and stretching; the locking effect on the nail rod is improved; the ideal orthopedic effect is ensured; the abnormal rotation and deformation can not occur.

Description

Pedicle screw and rod structure

Technical Field

The utility model belongs to the technical field of medical instrument, concretely relates to pedicle of vertebral arch nail stick structure.

Background

As is known in the art, the lumenal systems used clinically are generally composed of two parts, specifically, an anchor pedicle screw and a bridge connecting rod. The anchoring process is as follows: an pedicle screw is respectively inserted (also called as "implanted") into the upper vertebral body and the lower vertebral body of the target vertebral body, and the two pedicle screws are fixed through the nail rod as a connecting component, so that the upper vertebral body and the lower vertebral body are integrated, and the spinal cavity system, namely the pedicle screw rod structure, replaces the original lesion part and can bear various acting forces of the spinal column.

Further, as is known in the art, the minimally invasive puncture surgery has the advantages of small incision, less muscle dissection, less trauma, less bleeding, beautiful surgical site, fast recovery, etc., so the pedicle screw rod structure is also called a "minimally invasive puncture pedicle screw rod structure".

Technical information on pedicle screw-rod structures is not known in the published chinese patent literature, such as CN1700889A (device and method for subcutaneous placement of lumbar pedicle screws and connecting rods), CN101579254B (pedicle screws with closure device), CN103124534A (polyaxial pedicle attachment device for vertebral osteosynthesis), CN102948426B (transbilateral pedicle surgical cannula assembly instrument), and CN204410946U (an elastic spinal dynamic pedicle screw system), among others. Furthermore, technical information on pedicle screws and rods is also not known in foreign patent literature, such as US patents US5554157, US5549608, US5586984, US6280442, US6053917, US5964760, US6010503, US5910142, US6063089 and US2009/001889, such as world patents WO2009/015100, WO 2008/124772.

The pedicle screw rod structure in the prior art including the above mentioned Chinese and foreign patent documents is shown in fig. 4, and includes a screw body 1, a screw rod 2 (also referred to as "connecting rod", hereinafter the same) and a locking screw 3 (also referred to as "locking plug", hereinafter the same), wherein a screw seat 11 is formed at an upper portion of the screw body 1, the screw seat 11 is formed with a screw seat U-shaped cavity 111, an internal thread 1111 is formed on a cavity wall of the screw seat U-shaped cavity 111, the screw rod 2 is inserted into the screw seat U-shaped cavity 111 and is positioned at a bottom of the screw seat U-shaped cavity 111, the locking screw 3 is rotatably fitted with the internal thread 1111 at a position corresponding to an upper portion of the screw rod 2, and the screw rod 2 is fixedly connected with the screw body 1 at a position corresponding to the screw seat U-shaped cavity 111 by the locking screw 3.

Since the cross-sectional shape of the rod of the pedicle rod structure shown in fig. 4 is circular, the following technical problems exist in the actual use process: first, forces resisting rotational and longitudinal compressive stretching are relatively weak; secondly, the cross section of the nail rod is circular, so that the nail rod is easy to generate lateral convex deformity due to lack of corresponding reference marks (benchmarks) during pre-bending shaping; thirdly, when operating the locking screw, the surgeon often has difficulty in accurately mastering the degree of whether the locking screw is rotated in place; fourthly, the nail rod with the round cross section shape is easy to slide (also called as 'play') and rotate, so that the orthopedic effect is influenced to a certain extent; fifthly, because the cross section of the nail rod is circular, the shape of the cross section of the nail rod can affect the maintenance of the height of the vertebral body after operation due to deformation and/or rotation. In view of this need to be improved, the solution described below is made in this context.

Disclosure of Invention

The task of the utility model is to provide a help showing and promote the tensile ability of antagonism rotation and antagonism longitudinal extrusion, be favorable to providing the reference benchmark for the preflex is moulding and can avoid the nail stick to produce the side convex deformity, be of value to help the operation doctor accurately hold the locking screw when locking screw operation whether in place and can embody the locking effect to the nail stick ideal, be convenient for show improve antagonism slip and pivoted ability and can ensure the orthopedic effect of ideal, help embodying the good maintainability to postoperative centrum height and remove rotatory orthopedic effect and can reduce the pedicle screw stick structure that produces the intractable chest waist back disease of long-term sequela probability.

The task of the utility model is accomplished by the following steps that a pedicle screw rod structure comprises a screw body, a screw rod and a locking screw, wherein the upper part of the screw body is provided with a screw seat, the screw seat is provided with a screw seat U-shaped cavity, an internal thread is formed on the cavity wall of the screw seat U-shaped cavity, a nail rod is placed in the screw seat U-shaped cavity and supported at the bottom of the screw seat U-shaped cavity, a locking screw is arranged in the screw seat U-shaped cavity and is matched with the internal thread in a rotating mode at a position corresponding to the upper portion of the nail rod, the nail rod is fixedly connected with a screw body at a position corresponding to the screw seat U-shaped cavity through the locking screw, the screw seat is characterized in that a nail rod milling plane is formed on the surface of the nail rod and along the length direction of the nail rod, the cross section shape of the nail rod tends to be D-shaped through the nail rod milling plane, and the locking screw is in contact with the nail rod milling plane.

In a specific embodiment of the present invention, the width of the milling plane of the nail rod accounts for one sixth of the circumference of the nail rod.

In another particular embodiment of the invention, a pair of dimples is formed on the outer wall of the screw base, which dimples are spaced apart from each other by 180 ° around the circumferential direction of the screw base and from which are formed position reference marks of the screw body.

In another specific embodiment of the present invention, the screw body, the nail rod and the locking screw are made of titanium alloy.

In another specific embodiment of the present invention, the locking screw is a socket head locking screw.

The utility model provides one of the technical effects of the technical proposal, because the cross section shape of the nail rod is creatively changed from round into the shape which has the plane milled by the nail rod and tends to D shape on the premise of overcoming the technical prejudice in the prior art, the torsion and extraction force tests show that the nail rod has the capacity of resisting rotation and longitudinal extrusion and stretching; secondly, because the nail rod is provided with the nail rod milling plane, the nail rod milling plane can be used as a mark for contacting the bottom of the locking screw when an operator operates the locking screw, so that whether the locking screw is screwed in place or not can be accurately grasped, and the locking effect on the nail rod can be improved; thirdly, because the nail rod milling plane can obviously improve the sliding and rotating resistance of the nail rod, the ideal orthopedic effect can be ensured when the operation is used for treating the spine fracture or the scoliosis deformity; fourthly, because the nail rod has the plane milled by the nail rod, the abnormal rotation and deformation can not occur, the durable maintenance of the centrum height and the derotation orthopedic effect of the patient after the operation can not be lost, and the probability of generating the refractory thoracolumbar spine disease of the long-term sequelae can be obviously reduced.

Drawings

Fig. 1 is a sectional view of the present invention.

Fig. 2 is a schematic cross-sectional view of the nail bar shown in fig. 1.

Fig. 3 is a schematic view of the present invention in a use state.

Fig. 4 is a schematic diagram of a pedicle screw rod structure in the prior art.

Detailed Description

In order to make the technical essence and advantages of the present invention more clear, the applicant below describes in detail the embodiments, but the description of the embodiments is not a limitation of the present invention, and any equivalent changes made according to the inventive concept, which are only formal and not essential, should be considered as the technical scope of the present invention.

In the following description, all the concepts related to the directions or orientations of up, down, left, right, front and rear are based on the position state of fig. 1, and thus, should not be interpreted as a specific limitation to the technical solution provided by the present invention.

Referring to fig. 1, a screw body 1, a screw rod 2 and a locking screw 3 are shown, wherein a screw base 11 is formed at the upper part of the screw body 1, the screw base 11 is formed with a screw base U-shaped cavity 111, an internal thread 1111 is formed on the cavity wall of the screw base U-shaped cavity 111, the screw rod 2 is placed in the screw base U-shaped cavity 111 and supported at the bottom of the screw base U-shaped cavity 111, the locking screw 3 is placed in the screw base U-shaped cavity 111, the locking screw 3 is screwed (screw-fitted) with the internal thread 1111 at a position corresponding to the upper part of the screw rod 2, and the screw rod 2 is fixedly connected with the screw body 1 at a position corresponding to the screw base U-shaped cavity 111 by the locking screw 3.

As the technical scheme provided by the utility model: a shank milling plane 21 (also referred to as "plane" and the same applies hereinafter) is formed on the surface of the shank 2 and along the longitudinal direction of the shank 2, the shank milling plane 21 causes the cross-sectional shape of the shank 2 to be D-shaped, and the locking screw 3 (i.e., the bottom of the locking screw 3) is in contact with the shank milling plane 21.

Referring to fig. 2 in conjunction with fig. 1, the width of the nail rod milling plane 21 is one sixth of the circumference of the nail rod 2, specifically, an arc-shaped plane corresponding to a central angle α of 60 ° (60 degrees) is processed, for example, ground into a plane, which is the milling plane.

A pair of dimples 112 are formed on the outer wall of the screw base 11, the dimples 112 are spaced apart from each other by 180 ° in the circumferential direction of the screw base 11, and the dimples 112 form a position reference mark (to be mentioned later) of the screw body 1.

In this embodiment, the screw body 1, the nail bar 2, and the locking screw 3 are made of titanium alloy, and the locking screw 3 is a socket head locking screw.

Referring to fig. 2, according to the illustration of fig. 2 and in combination with the expert knowledge: the utility model discloses under the user state, one is that a nail stick 2 generally distributes two screw bodies 1 at least, constitutes a pair of dimple 112 on the outer wall of aforementioned screw seat 11 can regard as the position reference benchmark of double-phase adjacent screw body 1, particularly, the screw seat U font chamber 111 of the screw seat 11 of two screw bodies 1 corresponds each other to accurately put into respectively (inserting promptly) two screw seat U font chambeies 111 at the both ends of nail stick 2, make two screw bodies 1 and nail stick 2 three be located same straight line. Pre-bending the nail rod 2 according to the radian of the spine of a patient, then placing the nail rod 2 into the U-shaped cavity 111 of the screw seat, and then screwing the locking screw 3. When there are a plurality of screw bodies 1 with respect to one nail rod 2, the assembling, i.e., the operation process is the same as described above.

To sum up, the technical solution provided by the present invention remedies the defects in the prior art, successfully completes the invention task, and faithfully embodies the technical effects mentioned in the above technical effect column by the applicant.

Claims (5)

1. A pedicle screw-rod structure comprises a screw body (1), a screw rod (2) and a locking screw (3), wherein a screw seat (11) is formed at the upper part of the screw body (1), the screw seat (11) is formed with a screw seat U-shaped cavity (111), an internal thread (1111) is formed on the cavity wall of the screw seat U-shaped cavity (111), the screw rod (2) is placed in the screw seat U-shaped cavity (111) and supported at the bottom of the screw seat U-shaped cavity (111), the locking screw (3) is positioned in the screw seat U-shaped cavity (111) and is screwed with the internal thread (1111) at a position corresponding to the upper part of the screw rod (2), the screw rod (2) is fixedly connected with the screw body (1) at a position corresponding to the screw seat U-shaped cavity (111) by the locking screw (3), and the pedicle screw is characterized in that a screw rod plane (21) is formed on the surface of the screw rod (2) and along the length direction of the screw rod (2), the cross section of the nail rod (2) is inclined to be D-shaped by the nail rod milling plane (21), and the locking screw (3) is contacted with the nail rod milling plane (21).

2. The pedicle screw-rod structure according to claim 1, wherein the width of the screw-rod milling plane (21) is one sixth of the circumference of the screw rod (2).

3. The pedicle screw rod structure according to claim 1, wherein a pair of micro-recesses (112) are formed on an outer wall of the screw receptacle (11), the micro-recesses (112) being spaced apart from each other by 180 ° around a circumferential direction of the screw receptacle (11) and constituting position reference marks of the screw body (1) by the micro-recesses (112).

4. The pedicle screw-rod structure according to claim 1, wherein the screw body (1), the screw rod (2) and the locking screw (3) are titanium alloy.

5. The pedicle screw-rod arrangement according to claim 1 or 4, wherein the locking screw (3) is a socket head locking screw.