WO2024237679A1 - Pedicle screw assembly - Google Patents

Abstract

Disclosed is a pedicle screw assembly. The pedicle screw assembly according to an aspect of the present invention includes: a screw member which extends in one direction and couples to a pedicle; and a separation prevention member for rotatably supporting the screw member. The screw member includes: a screw body which extends in the one direction and is at least partially inserted into the pedicle; a screw head positioned at one end of the extending direction of the screw body and coupled to the separation prevention member so as to be rotatable about the axis in the one direction; and a screw protrusion coupled to the screw head so as to face the screw body with the screw head interposed therebetween, and coupled to the separation prevention member so as to be rotatable about the axis in the one direction.

Description

Pedicle screw assembly

The present invention relates to a pedicle screw assembly, and more particularly, to a pedicle screw assembly having a structure in which the length or angle of attachment can be easily changed without a separation process after attachment to the spine.

A pedicle screw, or pedicle screw (hereinafter referred to as "pedicle screw"), is a device that is fixed to the spine. Pedicle screws are widely used to restore a spine that has been deformed to an abnormal state to a normal state. Specifically, after a plurality of pedicle screws are fixed to a pedicle, a rod or the like is inserted into the fixed plurality of pedicle screws to apply an external force, thereby allowing the spine to be deformed to a normal state.

Pedicle screws penetrate the skin and muscles covering the spine to access the spine. Therefore, in order to attach a pedicle screw to the spine, an invasive process, that is, an incision in the surgical site, must be made first.

However, as the size of the invasive area increases, the difficulty of the surgery increases and the pain of the patient may increase. In addition, if the size of the invasive area increases excessively, there is also a risk of secondary infection such as bacteria.

Therefore, methods for inserting pedicle screws while minimizing the invasive area are being actively discussed recently.

Meanwhile, after multiple pedicle screws are connected to the spine, a component for applying external force to the spine, such as a rod, must be connected across the multiple pedicle screws. At this time, if the angles of some of the multiple pedicle screws are different, it is difficult to connect the rod accurately.

If the pedicle screw is not rotatable, the pedicle screw that is already attached to the spine must be separated and reattached to the spine at an angle. This causes additional pain to the patient and may also reduce the possibility of the success of the surgery.

Korean Patent Document No. 10-1252596 discloses a spinal fixation device. Specifically, it discloses a spinal fixation device including a pedicle screw that combines the advantages of a polyaxial screw with the advantages of a uniaxial screw, including at least two pedicle screws and at least one connecting member interposed therebetween.

However, the spinal fixation device disclosed in the above-mentioned prior document is achieved by the screw head being immovably supported within the screw shank to provide optimal restoration of the vertebrae. That is, the spinal fixation device disclosed in the above-mentioned prior document does not provide a method for adjusting the angle without detaching the pedicle screw already bonded to the vertebrae.

Korean Patent Document No. 10-1149094 discloses a method for improving the installation of pedicle screws. Specifically, it discloses a method for installing pedicle screws at an accurate location by accurately setting an incision location using a computer or the like and inserting a pedicle or the like into the set incision location.

However, the method for improving the installation of the pedicle screw disclosed in the above-mentioned prior document also only secures an accurate position. The above-mentioned prior document does not provide a method for easily adjusting the angle of attachment to the rod without detaching the screw already attached to the spine.

Korean Patent Document No. 10-1252596 (April 9, 2013)

Korean Patent Document No. 10-1149094 (May 25, 2012)

The present invention is intended to solve the above problems, and an object of the present invention is to provide a pedicle screw assembly having a structure capable of minimizing the invasive area.

Another object of the present invention is to provide a pedicle screw assembly having a structure that can easily adjust the angle while being connected to the spine.

Another object of the present invention is to provide a pedicle screw assembly having a structure in which the angle can be easily adjusted without a separation process while the screw is connected to the spine.

Another object of the present invention is to provide a pedicle screw assembly having a structure in which the positions at which a plurality of screws are connected can be changed without changing the combined length of the screws.

Another object of the present invention is to provide a pedicle screw assembly having a structure in which a screw coupled to a spine and a state of coupling of another configuration can be stably maintained.

The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below.

According to one aspect of the present invention, a pedicle screw assembly is provided, comprising: a screw member extending in one direction and coupled with a pedicle; and a disengagement prevention member rotatably supporting the screw member, wherein the screw member comprises: a screw body extending in the one direction and at least partially inserted into the pedicle; a screw head positioned at one end of the screw body in the extending direction and rotatably coupled to the disengagement prevention member about an axis in the one direction; and a screw protrusion portion coupled with the screw head so as to face the screw body with the screw head interposed therebetween and rotatably coupled to the disengagement prevention member about an axis in the one direction, wherein the disengagement prevention member comprises a disengagement prevention body including a portion rotatably receiving the screw head and another portion communicating with the portion rotatably receiving the screw protrusion and formed to have a cross-sectional area less than or equal to the portion.

At this time, a pedicle screw assembly can be provided, wherein the detachment prevention body includes a detachment prevention hollow formed penetratingly therein along the one direction to rotatably receive the screw head and the screw projection; a screw head support surface rotatably supporting the screw head on one side in the one direction; and a screw projection support surface continuous with the screw head support surface and rotatably receiving the screw projection on the other side in the one direction.

In addition, a pedicle screw assembly may be provided in which the screw head is formed such that its outer surface has at least a partial curve, and the screw head support surface is formed as a curved surface that extends roundly so as to be convex toward the radial outer side.

At this time, a pedicle screw assembly can be provided in which the screw projection is formed to have a cross-section having a diameter smaller than the maximum diameter of the cross-section of the screw head, and the screw projection support surface is formed as a curved surface surrounding the outer periphery of the screw projection.

In addition, a pedicle screw assembly may be provided, including a load support member coupled with the anti-separation member along the one direction and having an external load penetratingly coupled along the other direction; and a load support nut coupled with the load support member so as to face the anti-separation member with the load interposed therebetween along the one direction.

At this time, a pedicle screw assembly can be provided, wherein the load support member includes a member receiving space positioned therein for receiving the detachment prevention member; a rod receiving space communicated with the member receiving space for receiving the load; and a support nut receiving space communicated with the load receiving space and positioned facing the member receiving space with the rod receiving space interposed therebetween.

In addition, a pedicle screw assembly can be provided in which the load support member includes a load support screw thread formed on an inner surface of an outer circumference that partially surrounds the support nut receiving space and is screw-engaged with screw threads formed on the outer circumference of the load support nut.

At this time, a spinal screw assembly may be provided in which the load support member is coupled with the anti-separation member on one side of the one direction and the load support nut on the other side of the one direction, and the load is positioned between the anti-separation member and the load support nut.

Additionally, a pedicle screw assembly may be provided in which the load support nut is positioned between a first position for supporting the load so that the load is in close contact with the anti-dislocation member and a second position for supporting the load so that the load is spaced from the anti-dislocation member.

At this time, a pedicle screw assembly may be provided in which the load support member includes a load engaging opening formed through an outer surface radially surrounding the load receiving space and the support nut receiving space to provide an insertion passage for the load.

In addition, a pedicle screw assembly can be provided in which the load supporting member includes a ring receiving space that is communicated with the member receiving space and is positioned to face the load receiving space with the member receiving space interposed therebetween, and the anti-separation member includes a anti-separation ring that is coupled with the screw head to face the screw protrusion and is received in the ring receiving space.

At this time, a pedicle screw assembly may be provided in which a hollow space is formed inside the anti-separation ring, a anti-separation opening is sunken into the outer periphery thereof, and the inner diameter of the anti-separation ring is formed to have a value less than the maximum diameter of the cross-section of the screw head.

In addition, a pedicle screw assembly may be provided in which the anti-dislocation ring is received in the ring receiving space after being pressed radially inwardly so that the anti-dislocation opening is at least partially reduced, and the anti-dislocation ring received in the ring receiving space is deformed radially inwardly so that the anti-dislocation opening is at least partially increased.

According to the above configuration, the pedicle screw assembly according to the embodiment of the present invention can minimize the invasive area.

In addition, according to the above configuration, the pedicle screw assembly according to the embodiment of the present invention can easily adjust the angle while being connected to the spine.

In addition, according to the above configuration, the pedicle screw assembly according to the embodiment of the present invention can change the position at which a plurality of screws are connected without changing the coupling length of the screws.

In addition, according to the above configuration, the pedicle screw assembly according to the embodiment of the present invention can easily adjust the angle without a separation process while the screw is connected to the spine.

In addition, according to the above configuration, the pedicle screw assembly according to the embodiment of the present invention can stably maintain the coupling state of the screw coupled to the spine and a different configuration.

It should be understood that the effects of the present invention are not limited to the effects described above, but include all effects that can be inferred from the composition of the invention described in the detailed description or claims of the present invention.

FIG. 1 is a perspective view illustrating a pedicle screw assembly according to an embodiment of the present invention.

Figure 2 is an exploded perspective view illustrating the configuration of the pedicle screw assembly of Figure 1.

FIG. 3 is a perspective view illustrating a screw member provided in the pedicle screw assembly of FIG. 1.

Figure 4 is a plan view illustrating the screw member of Figure 3.

Figure 5 is a cross-sectional view taken along line A-A of the screw member of Figure 3.

FIG. 6 is an exploded perspective view showing a detachment prevention member and a load support member provided in the pedicle screw assembly of FIG. 1.

Figure 7 is an exploded plan view showing the detachment prevention member and load support member of Figure 6.

Fig. 8 is a B-B cross-sectional view illustrating the detachment prevention member and load supporting member of Fig. 6.

Fig. 9 is a C-C cross-sectional view illustrating the detachment prevention member and load supporting member of Fig. 6.

FIG. 10 is a perspective view illustrating a driver support member provided in the pedicle screw assembly of FIG. 1.

Fig. 11 is a D-D cross-sectional view illustrating the driver support member of Fig. 10.

FIG. 12 is a cross-sectional side view illustrating a rotation process of a pedicle screw assembly according to an embodiment of the present invention.

Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those with ordinary skill in the art can easily practice the present invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein. In order to clearly describe the present invention, parts that are not related to the description are omitted in the drawings, and the same reference numerals are assigned to the same or similar components throughout the specification.

The words and terms used in this specification and claims should not be construed as limited to their usual or dictionary meanings, but should be interpreted as having meanings and concepts consistent with the technical idea of the present invention, in accordance with the principles by which the inventor can define terms and concepts in order to best describe his or her invention.

Therefore, the embodiments described in this specification and the configurations illustrated in the drawings correspond to preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, so that the corresponding configurations may have various equivalents and modified examples that can replace them at the time of filing of the present invention.

In the following description, descriptions of some components may be omitted to clarify the features of the present invention.

The term "communicating" as used in the following description means that one or more members are connected to each other in a fluidic manner. In one embodiment, the communication may be formed by members such as conduits, pipes, or tubing. In the following description, the communication may be used to mean that one or more members are "fluidically connected" to each other.

The term "fluid" used in the following description means any form of material that flows due to an external force and can change shape or volume, etc. In one embodiment, the fluid may be a liquid such as water or a gas such as air.

The terms “upper side,” “lower side,” “left side,” “right side,” “front side,” and “rear side” used in the following description are to be understood with reference to the coordinate system depicted throughout the accompanying drawings.

Referring to FIGS. 1 and 2, a pedicle screw assembly (10) according to an embodiment of the present invention is illustrated. The pedicle screw assembly (10) according to an embodiment of the present invention can be coupled to a pedicle. A separately provided rod (R) is coupled to the pedicle screw assembly (10) coupled to the pedicle, thereby enabling an external force to be applied to the pedicle.

For this purpose, a plurality of pedicle screw assemblies (10) may be provided. The plurality of pedicle screw assemblies (10) may be coupled to the pedicle at different locations. The load may be coupled to each of the plurality of pedicle screw assemblies (10) to apply an external force to the pedicle.

The following description assumes that the pedicle screw assembly (10) is coupled to the pedicle of a human body. Alternatively, the pedicle screw assembly (10) according to an embodiment of the present invention may be provided as any device that is inserted into the human body and coupled to a bone.

A pedicle screw assembly (10) according to an embodiment of the present invention may be formed to have a length in one direction, in the front-back direction in the illustrated embodiment. The pedicle screw assembly (10) may be inserted into a human body along its length direction, so that one side in the length direction, in the illustrated embodiment, the front side, may be coupled to the pedicle.

Additionally, the configuration for forming a pedicle joint can be coupled to the pedicle screw assembly (10) through the other longitudinal side of the pedicle screw assembly (10).

At this time, the pedicle screw assembly (10) according to the embodiment of the present invention can be rotated relatively to the component (i.e., the screw member (100) to be described later) that is coupled to the spine with respect to the component (i.e., the detachment prevention member (200) to be described later) that supports the same. Accordingly, some of the components of the plurality of pedicle screw assemblies (10) can be rotated while coupled to the spine, and adjusted to an angle appropriate for coupling with the rod (R).

At the same time, the configuration that is coupled with the spine can be limited in its longitudinal movement by the configuration for supporting the rod (R). Accordingly, the pedicle screw assembly (10) can be maintained at a preset position while only the angle is adjusted, so that the rod (R) can be coupled accurately.

In the illustrated embodiment, the pedicle screw assembly (10) includes a screw member (100), a detachment prevention member (200), a load support member (300), a load support nut (400), and a driver support member (500).

In addition, as shown in FIGS. 1 and 2, the pedicle screw assembly (10) is coupled with a rod (R) and a driver (d). At this time, the rod (R) and the driver (d) may be provided separately from the pedicle screw assembly (10).

The screw member (100) is a part where the pedicle screw assembly (10) is directly connected to the pedicle. The screw member (100) can be fixedly connected to the pedicle. At this time, the screw member (100) can be provided in a form that is fixedly connected to the pedicle by an external force, but can be separated from the pedicle by an external force. In one embodiment, the screw member (100) can be provided in the form of a screw.

The screw member (100) constitutes one longitudinal end of the pedicle screw assembly (10). In the illustrated embodiment, the screw member (100) constitutes a front end of the pedicle screw assembly (10). The pedicle screw assembly (10) can be moved anteriorly to be introduced into the human body and moved posteriorly to be withdrawn from the human body.

The screw member (100) is coupled with the detachment prevention member (200). Specifically, the screw member (100) can be coupled with the detachment prevention member (200) so as to be rotatable about its longitudinal axis, but prevented from moving in the longitudinal direction. That is, the screw member (100) can be coupled with the detachment prevention member (200) so as to be rotatable.

As will be described later, the anti-separation member (200) can be rotatably coupled about its longitudinal axis with respect to the load support member (300). Accordingly, the screw member (100) can also be rotatably coupled with the load support member (300).

The screw member (100) is coupled with the load support member (300). The screw member (100) can be coupled with the load support member (300) via the detachment prevention member (200). The screw member (100) can be coupled with the load support member (300) so as to be rotatable about its longitudinal direction, but prevented from moving in the longitudinal direction.

A driver (d) can be detachably coupled to the screw member (100). After the pedicle screw assembly (10) is inserted into the human body, the driver (d) can penetrate the rod support member (300), the rod support nut (400), and the driver support member (500) and be coupled to one end of the screw member (100) in the longitudinal direction.

In the embodiments shown in FIGS. 3 to 5, the screw member (100) includes a screw body (110), a screw head (120), a screw thread (130), a screw protrusion (140), and a screw cavity (150).

The screw body (110) constitutes a portion of the outer shape of the screw member (100). The screw body (110) extends in the extension direction of the screw member (100), in the forward and backward direction in the illustrated embodiment.

The screw body (110) is combined or formed with another configuration of the screw member (100). In the illustrated embodiment, a screw head (120) is combined with one end of the screw body (110) in the extension direction, i.e., the rear end. A screw thread (130) is formed on the outer periphery of the screw body (110), and a screw hollow (150) is formed on the inside of the screw body (110).

The screw body (110) is a part where the pedicle screw assembly (10) is directly connected to the spine. For this purpose, the screw body (110) may have a shape that allows it to be easily inserted into the spine. In the illustrated embodiment, the screw body (110) is formed in a shape of a cone or concave whose cross-sectional area increases as it moves from the other end in the extension direction, i.e., the front end, to the one end in the extension direction, i.e., the rear end.

The screw head (120) constitutes another part of the outer shape of the screw member (100). The screw head (120) is coupled with one end of the screw body (110) in the extension direction, the rear end in the illustrated embodiment.

The screw head (120) is coupled with the detachment prevention member (200). Specifically, the screw head (120) is rotatably received in the detachment prevention hollow (211) of the detachment prevention body (210). The screw head (120) is rotatably supported by a screw head support surface (212) surrounding the detachment prevention hollow (211).

Accordingly, it will be understood that the screw member (100) is rotatably coupled to the anti-separation member (200).

The screw head (120) may have any shape that can be rotatably coupled with the anti-separation member (200). In the illustrated embodiment, the screw head (120) is configured as a portion of a sphere whose outer surface is formed into a curved surface.

One side in the height direction of the screw head (120), the lower side in the illustrated embodiment, is continuous with the upper end of the screw body (110). On the other side in the height direction of the screw head (120), the upper side in the illustrated embodiment, a screw protrusion (140) is formed.

As will be described later, the screw projection (140) is supported by the screw projection support surface (213) and the rod (R) and is restricted from moving in the axial direction, i.e., in the forward and backward direction in the illustrated embodiment. Accordingly, it will be understood that the screw head (120) is only capable of rotating about the center of the screw body (110).

The screw thread (130) is formed on the outer surface of the screw body (110). The screw thread (130) is configured to maintain a state of coupling between the screw body (110) and the spine. The screw thread (130) is coupled with the inner surface of the spine.

The screw thread (130) extends obliquely along the length direction of the screw body (110). At this time, the screw thread (130) may extend in a helical shape. The screw thread (130) is formed to protrude outward from the outer surface of the screw body (110).

The screw projection (140) constitutes a part of the screw member (100) supported by the anti-separation member (200) and the rod (R). The screw projection (140) is rotatably coupled to the anti-separation member (200) together with the screw head (120). At this time, the screw projection (140) is restricted from moving in the longitudinal direction of the screw member (100), i.e., in the forward-backward direction, by the screw projection support surface (213) of the anti-separation member (200) and the rod (R).

Accordingly, since the screw projection (140) is provided, the spinal screw assembly (10) according to the embodiment of the present invention can rotate about the longitudinal direction of the screw member (100), but movement in the longitudinal direction can be limited.

The screw protrusion (140) is continuous with the screw head (120). In the illustrated embodiment, the screw protrusion (140) is located on the other side in the height direction of the screw head (120), i.e., the rear side. The screw protrusion (140) is positioned to face the screw body (110) and the screw thread (130) with the screw head (120) interposed therebetween.

The screw protrusion (140) may have any shape that can limit the longitudinal movement of the screw member (100) by coming into contact with the anti-separation body (210) or the rod (R). In the illustrated embodiment, the screw protrusion (140) is formed in a disc shape with a circular cross-section and a thickness in the front-back direction.

At this time, the diameter of the cross-section of the screw projection (140) may be formed to be less than the maximum value of the diameter of the cross-section of the screw head (120). As will be described later, the shortest distance between the screw head support surfaces (212) is formed to be greater than the longest distance between the screw projection support surfaces (213).

Accordingly, the screw head (120) is supported by the screw head support surface (212) and is prevented from moving in the longitudinal direction.

The screw hollow (150) is a space formed inside the screw member (100). The screw hollow (150) provides a space into which the driver (d) is inserted. In addition, the screw hollow (150) reduces the weight of the entire screw member (100) and allows the screw member (100) to be easily coupled to the spine.

The screw hollow (150) is formed longitudinally penetrating the inside of the screw member (100). In the illustrated embodiment, the screw hollow (150) is formed penetrating through the screw body (110), the screw head (120), and the screw protrusion (140) in the forward and backward direction.

The screw cavity (150) can be divided into a plurality of parts. The plurality of parts can be formed to be connected to each other, but have different cross-sectional areas. In the illustrated embodiment, the screw cavity (150) includes a first screw cavity (151) and a second screw cavity (152).

The first screw hollow (151) is a portion of the screw hollow (150) that is partially formed in the screw body (110) and the screw head (120). Each end of the length direction of the first screw hollow (151), in the illustrated embodiment, the front end and the rear end, are each formed open.

The second screw hollow (152) is a portion formed in the remaining portion of the screw head (120) and the screw protrusion (140) among the portions of the screw hollow (150). Each end of the second screw hollow (152) in the longitudinal direction, the front end and the rear end in the illustrated embodiment, are each formed open. A driver (d) can be inserted into the second screw hollow (152).

At this time, the diameter of the cross-section of the first screw hollow (151) may be formed to be less than or equal to the diameter of the cross-section of the second screw hollow (152). Preferably, the diameter of the cross-section of the first screw hollow (151) may be formed to be less than the diameter of the cross-section of the second screw hollow (152) or the diameter of the driver (d).

Accordingly, the driver (d) is inserted into the second screw hollow (152) to apply rotational force to the screw member (100), but its insertion into the first screw hollow (151) may be restricted.

The detachment prevention member (200) maintains the coupled state of the screw member (100) and the load support member (300). The detachment prevention member (200) is coupled to the screw member (100) and the load support member (300), respectively.

Specifically, the anti-separation member (200) surrounds the other side in the longitudinal direction of the screw member (100), the rear side in the illustrated embodiment, and is coupled with the screw member (100). The other side in the longitudinal direction of the screw member (100) can be accommodated inside the anti-separation member (200). At this time, the anti-separation member (200) can rotatably accommodate the other side in the longitudinal direction of the screw member (100).

The detachment prevention member (200) is coupled with the load support member (300). The detachment prevention member (200) is accommodated in a member accommodation space (310) formed inside the load support member (300). The detachment prevention member (200) can be arranged so as not to be exposed to the outside of the load support member (300).

In the embodiments shown in FIGS. 6 to 9, the detachment prevention member (200) includes a detachment prevention body (210) and a detachment prevention ring (220).

The anti-separation body (210) rotatably receives a portion of the other side in the longitudinal direction of the screw member (100), specifically, the screw head (120) and the screw protrusion (140). The anti-separation body (210) is received in the member receiving space (310) of the load supporting member (300) and is supported by the inner surface of the load supporting member (300). In one embodiment, the anti-separation body (210) rotatably receives the screw member (100) and can be rotatably received in the member receiving space (310).

At the same time, the anti-separation body (210) can limit the longitudinal movement of the screw head (120) and the screw projection (140), i.e., the forward and backward movement in the illustrated embodiment. Accordingly, the screw member (100) coupled to the anti-separation body (210) can rotate about its longitudinal axis, but the movement in the longitudinal direction can be limited.

In the illustrated embodiment, the anti-separation body (210) includes an anti-separation hollow (211), a screw head support surface (212), and a screw projection support surface (213).

The anti-separation hollow (211) rotatably accommodates a screw head (120) and a screw protrusion (140) continuous therewith. The anti-separation hollow (211) is defined as a space formed inside the anti-separation body (210).

The anti-separation hollow (211) may have a shape corresponding to the shape of the anti-separation body (210). In the illustrated embodiment, the anti-separation hollow (211) has a circular cross-section and a height in the front-back direction, but the cross-section is formed as a space of a different three-dimensional shape along the height direction.

Each end of the extension direction of the anti-separation hollow (211), the front side and the rear side in the illustrated embodiment, are formed open, respectively. The screw head (120) and the screw protrusion (140) can be accommodated in the anti-separation hollow (211) through the front side end. The driver (d) can access the screw head (120) through the rear side end.

The anti-separation hollow (211) may include a portion that is at least partially spherical. A screw head (120) formed in a spherical shape is rotatably received in the portion. The portion is defined by being surrounded by a screw head support surface (212).

The anti-separation hollow (211) may include another portion that is at least partially disc-shaped. The other portion rotatably receives a screw projection (140) formed in a disc-shaped shape. The other portion is defined by being surrounded by a screw projection support surface (213).

The above part and the other part are connected to each other. Accordingly, the screw head (120) and the screw projection (140) which are connected to each other continuously can be accommodated together in the anti-separation hollow (211). In the illustrated embodiment, the above part is located on the front side and the other part is located on the rear side.

At this time, the diameter of the cross-section of the other part of the detachment prevention hollow (211) can be formed to be less than or equal to the minimum diameter of the cross-section of the part. Accordingly, the screw head (120) accommodated in the part does not enter the other part.

The screw head support surface (212) surrounds the above-mentioned portion of the detachment prevention hollow (211) in the radial direction. The screw head support surface (212) rotatably supports the screw head (120) accommodated in the detachment prevention hollow (211) in the radial direction.

The screw head support surface (212) is defined as a portion of the inner surface of the anti-separation body (210). In the illustrated embodiment, the screw head support surface (212) is defined as a lower portion of the inner surface of the anti-separation body (210).

The screw head support surface (212) may have a shape corresponding to the outer circumference of the screw head (120). In the illustrated embodiment, the screw head support surface (212) is formed in a rounded curved shape that extends along the inner circumference of the anti-separation body (210) and is convex toward the radial outside.

The screw head support surface (212) extends to surround the above-mentioned portion of the detachment prevention hollow (211). At this time, along the diametric direction of the detachment prevention hollow (211), the minimum value of the distance between the screw head support surfaces (212) may be greater than or equal to the maximum value of the distance between the screw protrusion support surfaces (213) along the same direction.

By the structure as described above, the screw head (120) accommodated in the above part of the detachment prevention hollow (211) is prevented from moving to the other part of the detachment prevention hollow (211).

The screw projection support surface (213) radially surrounds the other part of the anti-separation hollow (211). The screw projection support surface (213) rotatably supports the screw projection (140) accommodated in the anti-separation hollow (211) in the radial direction.

The screw projection support surface (213) is defined as another portion of the inner surface of the anti-separation body (210). In the illustrated embodiment, the screw projection support surface (213) is defined as the middle portion or the upper portion of the inner surface of the anti-separation body (210). The screw projection support surface (213) is continuous with the screw head support surface (212).

The screw projection support surface (213) may have a shape corresponding to the outer circumference of the screw projection (140). In the illustrated embodiment, the screw head support surface (212) is formed in a curved shape extending along the inner circumference of the detachment prevention body (210).

The screw projection support surface (213) extends to surround the other part of the anti-separation hollow (211). As described above, the maximum value of the distance between the screw projection support surfaces (213) along the diametric direction of the anti-separation hollow (211) may be less than or equal to the minimum value of the distance between the screw head support surfaces (212) along the same direction.

The anti-separation ring (220) rotatably receives the other part of the longitudinal side of the screw member (100). The anti-separation ring (220) is formed to have a larger outer diameter than the anti-separation body (210).

The anti-separation ring (220) prevents the anti-separation body (210) accommodated in the absence accommodation space (310) from being dislodged in the axial direction of the screw member (100), i.e., toward the front side in the illustrated embodiment. The anti-separation ring (220) supports the anti-separation body (210) on one side in the longitudinal direction, i.e., the front side.

The anti-separation ring (220) is coupled with the screw member (100). The anti-separation ring (220) is positioned so as to be biased toward one side of the length direction of the screw member (100), i.e., the front side, compared to the anti-separation body (210). The anti-separation ring (220) is positioned between the front end of the load support member (300) and the anti-separation body (210).

The anti-separation ring (220) is formed in an annular shape, and a anti-separation opening (221) may be formed on one side. The anti-separation opening (221) may form a space for the anti-separation ring (220) to be deformed in a shape such that the outer diameter thereof is reduced by being pressed. The anti-separation ring (220) may be deformed by being pressed radially inward while the screw member (100) is penetrated therethrough, and then may be combined with the load support member (300).

When the above pressurized state is released, the anti-separation ring (220) is deformed radially outwardly and can be brought into close contact with the load support member (300). Accordingly, the anti-separation ring (220) can stably support the anti-separation body (210) and the load (R) located at the rear side thereof.

At this time, the inner diameter of the detachment prevention ring (220) may be less than or equal to the minimum diameter of the cross-section of the screw head (120). Therefore, the detachment prevention ring (220) can prevent a situation in which the screw head (120) accommodated in the detachment prevention hollow (211) is arbitrarily pulled out.

Accordingly, it will be understood that the rearward movement of the screw member (100) combined with the detachment prevention member (200) is prevented by the screw projection support surface (213) and the load (R) combined therewith, and the forward movement of the screw member (100) is prevented by the detachment prevention ring (220).

Accordingly, the screw member (100) can be rotatably coupled to the anti-separation member (200), but its movement in the longitudinal direction can be blocked.

The load support member (300) is a configuration to which an external load (R) is coupled. The load support member (300) supports the external load (R). The external load (R) can be extended along the spine or the vertebrae by a plurality of load support members (300) provided on each of a plurality of spine screw assemblies (10).

The load support member (300) is coupled with the screw member (100). Specifically, it is coupled with the screw member (100) via the anti-separation member (200). The load support member (300) can rotatably receive the anti-separation member (200) that rotatably supports the screw member (100).

The load support member (300) extends in the longitudinal direction of the screw member (100), in the front-back direction in the illustrated embodiment. One side of the extension direction of the load support member (300), in the illustrated embodiment, the front side, surrounds the screw member (100) and the anti-separation member (200) coupled thereto. The other side of the extension direction of the load support member (300), in the illustrated embodiment, the rear side, is coupled with the driver support member (500).

A hollow space is formed inside the load support member (300). A driver (d) for manipulating the screw member (100) can be inserted into the load support member (300) in a retractable manner.

The load support member (300) is coupled to the driver support member (500). The load support member (300) can be at least partially accommodated in the driver support member (500). A portion of the load support member (300) can be extended out of the human body together with the driver support member (500).

In the embodiments illustrated in FIGS. 6 to 9, the load support member (300) includes a member receiving space (310), a ring receiving space (320), a load receiving space (330), a support nut receiving space (340), a load support screw thread (350), a load engaging opening (360), and a protrusion engaging groove (370).

The absence receiving space (310) is a space that receives the departure prevention body (210) of the departure prevention member (200). The absence receiving space (310) is defined as a portion of a space formed inside the load support member (300). In the illustrated embodiment, the absence receiving space (310) is located on the rear side of the ring receiving space (320) along the longitudinal direction of the load support member (300), that is, the front-back direction.

The absence receiving space (310) may have a shape corresponding to the shape of the detachment prevention body (210). In the illustrated embodiment, the absence receiving space (310) has a circular cross-section and a height in the front-back direction, but is configured such that the cross-sectional area changes at least partially along the height direction. In the illustrated embodiment, the front side of the absence receiving space (310) has a cylindrical shape. In addition, the rear side of the absence receiving space (310) is formed in a truncated cone shape whose cross-sectional area decreases toward the rear side.

The absence receiving space (310) is communicated with the ring receiving space (320) and the load receiving space (330). One side in the height direction of the absence receiving space (310), the front side in the illustrated embodiment, is communicated with the ring receiving space (320). The other side in the height direction of the absence receiving space (310), the rear side in the illustrated embodiment, is communicated with the load receiving space (330).

The ring receiving space (320) is a space for receiving the detachment prevention ring (220) of the detachment prevention member (200). The detachment prevention ring (220) is received in the ring receiving space (320) in a pressurized state so that the detachment prevention opening (221) is closed, and then is restored to its original shape, so that the detachment prevention opening (221) can be formed again.

The ring receiving space (320) is defined as another portion of the space formed inside the load supporting member (300). In the illustrated embodiment, the ring receiving space (320) is located on the front side of the member receiving space (310) along the longitudinal direction of the load supporting member (300), i.e., the front-back direction. The ring receiving space (320) is arranged to face the load receiving space (330) with the member receiving space (310) interposed therebetween.

The ring receiving space (320) may have a shape corresponding to the shape of the anti-separation ring (220). In the illustrated embodiment, the ring receiving space (320) is formed as a space in the shape of a disk having a circular cross section and a height in the front-back direction.

The ring receiving space (320) is connected to the absence receiving space (310). At this time, the outer diameter of the cross-section of the ring receiving space (320) may be formed to exceed the maximum value of the outer diameter of the cross-section of the absence receiving space (310). Therefore, the detachment prevention ring (220) received in the ring receiving space (320) is prevented from being arbitrarily detached from the ring receiving space (320) and moved to the absence receiving space (310).

The load receiving space (330) movably receives the load (R). The load receiving space (330) is defined as another portion of the space formed inside the load supporting member (300).

In the illustrated embodiment, the load receiving space (330) is located at the rear side of the member receiving space (310) along the longitudinal direction of the load supporting member (300), i.e., the front-back direction. The load receiving space (330) is arranged to face the ring receiving space (320) with the member receiving space (310) interposed therebetween.

The load receiving space (330) may have a shape corresponding to the shape of the load (R). As illustrated in FIG. 1, the load (R) has a cylindrical shape with a circular cross-section and a height in one direction, and the load receiving space (330) may be formed as a space having a width and height greater than the cross-sectional area of the load (R).

The load receiving space (330) is connected to the absence receiving space (310). The load (R) received in the load receiving space (330) can support the detachment prevention body (210) received in the absence receiving space (310).

The load receiving space (330) is connected to the load coupling opening (360). The load (R) can extend to the outside of the load support member (300) by penetrating the load receiving space (330) through the load coupling opening (360).

The support nut receiving space (340) is a space for receiving the load support nut (400). The support nut receiving space (340) is defined as another part of the space formed inside the load support member (300). In the illustrated embodiment, the support nut receiving space (340) is located at the rearmost side along the longitudinal direction of the load support member (300), that is, the front-back direction. The support nut receiving space (340) is arranged to face the member receiving space (310) with the load receiving space (330) interposed therebetween.

The support nut receiving space (340) may have a shape corresponding to the shape of the load support nut (400). In the illustrated embodiment, the support nut receiving space (340) is formed as a cylindrical space having a circular cross-section and a height in the front-back direction.

The support nut receiving space (340) is connected to the load receiving space (330). The load support nut (400) received in the support nut receiving space (340) can press the load (R) received in the load receiving space (330) toward one side in the longitudinal direction, that is, toward the front side in the illustrated embodiment. Accordingly, it can be said that the load support nut (400) supports both the load (R) and the anti-separation member (200).

The support nut receiving space (340) is communicated with the load coupling opening (360). Each side in the height direction of the support nut receiving space (340), the upper side and the lower side in the illustrated embodiment, is communicated with the outside by the load coupling opening (360).

Accordingly, the load (R) enters the load receiving space (330) or the support nut receiving space (340) through the load coupling opening (360), and then moves toward the member receiving space (310) by the load support nut (400) to support the anti-separation member (200) and the screw member (100) rotatably coupled thereto.

A load support screw thread (350) is formed on the inner surface of the load support member (300) surrounding the support nut receiving space (340).

The load support screw thread (350) is coupled with the load support nut (400). The load support screw thread (350) is formed on the inner surface of the load support member (300) surrounding the support nut receiving space (340). The load support screw thread (350) can be screw-coupled with the screw thread formed on the outer surface of the load support nut (400).

As the load support screw thread (350) is formed, the distance at which the load support nut (400) is received in the support nut receiving space (340) can be adjusted. As a result, the position of the load (R) supported by the load support nut (400) can also be adjusted.

The load coupling opening (360) is defined as an opening formed through the outer surface of the load support member (300). The load coupling opening (360) communicates the load receiving space (330) and the support nut receiving space (340) with the outside. The load coupling opening (360) communicates with the load receiving space (330) and the support nut receiving space (340), respectively.

Accordingly, as described above, the load (R) can be partially accommodated in the load receiving space (330) or the support nut receiving space (340) through the load coupling opening (360) and then moved toward the anti-separation member (200) by the load supporting nut (400).

The load coupling opening (360) is formed through the height-directed surface of the load support member (300). The load coupling opening (360) extends in the longitudinal direction of the load support member (300), in the front-back direction in the illustrated embodiment. One longitudinal side of the load coupling opening (360), in the illustrated embodiment, the front side, is closed. The load (R) can be supported by the closed front side of the load coupling opening (360).

The other side in the longitudinal direction of the load coupling opening (360), i.e., the rear side in the illustrated embodiment, is open. In one embodiment, the load (R) can also enter the load receiving space (330) or the support nut receiving space (340) through the other side, i.e., the rear side, of the load coupling opening (360).

A plurality of load coupling openings (360) may be formed. In the illustrated embodiment, the load coupling openings (360) are formed on the upper and lower surfaces of the load support member (300), respectively. The pair of load coupling openings (360) are arranged to face each other with a load receiving space (330) or a support nut receiving space (340) therebetween.

The projection coupling groove (370) is a portion where the load support member (300) is coupled with the driver support member (500). The projection coupling groove (370) accommodates a support member coupling projection (530) provided on the driver support member (500).

As will be described later, the support member engaging protrusion (530) is formed to be inclined so that its cross-sectional area increases in a direction opposite to that of the detachment prevention member (200). Accordingly, the support member engaging protrusion (530) accommodated in the protrusion engaging groove (370) may not be arbitrarily separated without the application of an external force.

The projection engaging groove (370) may have a shape corresponding to the shape of the support member engaging groove (530). In the illustrated embodiment, the projection engaging groove (370) has a circular cross-section and is formed as a space in the shape of a disk having a thickness in the left-right direction.

The protrusion engaging groove (370) may be positioned in a portion of the load supporting member (300) where the load engaging opening (360) is not formed. In the illustrated embodiment, the protrusion engaging groove (370) is formed penetrating the widthwise surface of the load supporting member (300).

A plurality of protrusion-engaging grooves (370) may be formed. A plurality of protrusion-engaging grooves (370) may be formed at different positions while being spaced apart from each other. In the illustrated embodiment, a pair of protrusion-engaging grooves (370) are formed. A pair of protrusion-engaging grooves (370) are formed to penetrate each side of the width direction of the load support member (300), i.e., the left and right sides in the illustrated embodiment.

Accordingly, it will be understood that the load coupling openings (360) and the protrusion coupling grooves (370) are alternately arranged along the outer periphery of the load support member (300).

Referring again to FIG. 1, a pedicle screw assembly (10) according to an embodiment of the present invention includes a load support nut (400).

The load support nut (400) is coupled with the load support member (300) to support the load (R). The load support nut (400) presses the load (R) toward one longitudinal side of the load support member (300), the front side in the illustrated embodiment. In other words, the load support nut (400) supports the load (R) toward the other longitudinal side of the load support member (300), the rear side in the illustrated embodiment.

A hollow space is formed through the inside of the load support nut (400). The hollow space is connected to the member receiving space (310), the ring receiving space (320), the rod receiving space (330), and the support nut receiving space (340) formed inside the load support member (300). In addition, the hollow space is connected to the driver receiving space (510) and the support member receiving space (520), thereby forming a passage for the penetration of the driver (d).

The load support nut (400) is coupled with the load support member (300). The load support nut (400) is received in the support nut receiving space (340) and is screw-coupled with the load support screw thread (350). The load support nut (400) is positioned to face the anti-separation member (200) with the load (R) interposed therebetween.

Meanwhile, the distance at which the load support nut (400) is coupled to the load support member (300) can be adjusted. In other words, the ratio of the portion of the load support nut (400) accommodated in the support nut accommodation space (340) can be changed.

Accordingly, the load support nut (400) may be accommodated in the support nut accommodation space (340) until the load (R) comes into contact with the anti-separation member (200), or may be accommodated in the support nut accommodation space (340) so that the load (R) is spaced from the anti-separation member (200).

Accordingly, even if the length of the screw member (100) coupled to the spine must be changed, the height at which the load (R) is coupled can be adjusted by changing the position of the load support nut (400) without adjusting the coupling length of the screw member (100) itself.

The driver support member (500) accommodates and supports the driver (d). The driver (d) can be moved along the longitudinal direction and coupled with the screw member (100) without being moved in any direction, i.e., in the radial direction, by the driver support member (500).

The driver support member (500) is coupled to the load support member (300). The driver support member (500) can at least partially accommodate the load support member (300). In one embodiment, the driver support member (500) can be hook-coupled to the load support member (300).

The driver support member (500) extends in a direction corresponding to the direction of introduction and withdrawal of the pedicle screw assembly (10). In the illustrated embodiment, the driver support member (500) extends in the forward and backward direction. One longitudinal side of the driver support member (500), in the illustrated embodiment, the forward side, is coupled with the rod support member (300).

In the embodiments illustrated in FIGS. 10 and 11, the driver support member (500) includes a driver receiving space (510), a support member receiving space (520), and a support member engaging protrusion (530).

The driver accommodation space (510) is a space formed inside the driver support member (500). The driver accommodation space (510) accommodates the driver (d). The driver accommodation space (510) extends in the longitudinal direction of the driver support member (500), in the front-back direction in the illustrated embodiment. Each side of the longitudinal direction of the driver accommodation space (510), in the front side and the rear side in the illustrated embodiment, is formed open, respectively, to form a passage through which the driver (d) passes.

The driver receiving space (510) may have a shape corresponding to the shape of the driver (d). In the illustrated embodiment, the driver receiving space (510) is formed as a columnar space having a predetermined cross-section and a length in the front-back direction.

One side of the longitudinal direction of the driver receiving space (510), located at the front side in the illustrated embodiment, can be defined as a support member receiving space (520).

The support member receiving space (520) is a space for receiving the load support member (300). A portion of the load support member (300) in the longitudinal direction can be received in the support member receiving space (520). In one embodiment, the load support member (300) can be received by being introduced into the support member receiving space (520) until the support member engaging protrusion (530) is inserted into the engaging groove (370).

The support member receiving space (520) may have a shape corresponding to the shape of the load support member (300). In the illustrated embodiment, the support member receiving space (520) has a cross-section that partially includes a curve and is formed as a space extending in the front-rear direction.

A support member coupling protrusion (530) is positioned in the support member receiving space (520).

The support member coupling protrusion (530) is a portion where the driver support member (500) is coupled with the load support member (300). The support member coupling protrusion (530) is inserted into the protrusion coupling groove (370). The inserted support member coupling protrusion (530) is not arbitrarily pulled out from the protrusion coupling groove (370) without the application of an external force.

The support member coupling protrusion (530) is positioned on the inner surface of the driver support member (500) surrounding the support member receiving space (520). In the illustrated embodiment, the support member coupling protrusion (530) is formed to protrude from the inner surface in the width direction of the driver support member (500).

The support member engaging protrusion (530) may have any shape that can be easily inserted into the protrusion engaging groove (370), but cannot be arbitrarily withdrawn from the protrusion engaging groove (370). In the embodiment illustrated in FIG. 11, the support member engaging protrusion (530) is formed such that its cross-sectional area increases in the direction from one side of the length direction of the driver support member (500) toward the other side, that is, in the direction from the front side toward the rear side.

In addition, the support member coupling protrusion (530) extends obliquely in a direction from one side to the other side, that is, from the front side to the rear side, toward the inside of the driver support member (500). That is, the support member coupling protrusion (530) is formed so that the rear side protrudes longer than the front side protrudes.

Accordingly, when the load support member (300) moves toward the driver support member (500), the load support member (300) comes into contact with the inclined surface of the support member engaging protrusion (530) and can press the driver support member (500) outwardly. When the support member engaging protrusion (530) is accommodated in the engaging groove (370), the supporting member engaging protrusion (530) is prevented from being arbitrarily pulled out of the engaging groove (370) by the rear side surface of the support member engaging protrusion (530), i.e., the surface extending in the left-right direction.

The support member coupling protrusions (530) may be provided in multiple numbers. The multiple support member coupling protrusions (530) may be arranged at different positions while being spaced apart from each other. In the illustrated embodiment, the support member coupling protrusions (530) are provided in pairs and are arranged spaced apart from each other in the width direction of the driver support member (500), that is, in the left-right direction. The pair of support member coupling protrusions (530) are respectively positioned on the left and right inner surfaces of the driver support member (500). The pair of support member coupling protrusions (530) are arranged to face each other with the support member receiving space (520) therebetween.

Referring to FIG. 12, the joint structure of each component of the spinal screw assembly (10) according to an embodiment of the present invention is illustrated as an example.

In the illustrated embodiment, the screw member (100) is rotatably coupled with the anti-separation member (200). In addition, the anti-separation member (200) is coupled with the load support member (300). The load (R) also passes through the load coupling opening (360) and is coupled with the load support member (300).

At this time, the screw head (120) is accommodated in the detachment prevention hollow (211) and is rotatably supported by a screw head support surface (212) configured to include a rounded surface that is convex toward the radial outside. In addition, a screw protrusion (140) continuous with the screw head (120) is also accommodated in the detachment prevention hollow (211) and is rotatably supported by a screw protrusion support surface (213) formed in the inner peripheral shape of a disc.

In the above state, when the screw body (110) is coupled to the spine, the screw member (100) itself is fixed. Therefore, the relative rotation of the screw member (100) and the detachment prevention member (200) can be achieved by rotating the detachment prevention member (200) counterclockwise (A) or clockwise (B) about the longitudinal direction of the screw member (100) as an axis.

Meanwhile, as described above, the member receiving space (310) for receiving the detachment prevention member (200) is connected to the load receiving space (330) for receiving the load (R). In addition, each end of the detachment prevention hollow (211) in the longitudinal direction is open, so that the detachment prevention hollow (211) is connected to the load receiving space (330).

Accordingly, the screw projection (140) accommodated in the detachment prevention hollow (211) can be supported by the load (R) accommodated in the load accommodation space (330). Meanwhile, a load support nut (400) is positioned in the support nut accommodation space (340) that is connected to the load accommodation space (330). The load support nut (400) can support the load (R).

Accordingly, the screw member (100) can be prevented from moving in the direction of separation from the coupled spine, i.e., toward the load (R).

Furthermore, a detachment prevention ring (220) is coupled to a portion of the screw head (120), that is, a front portion in the embodiment illustrated in FIG. 12. The inner diameter of the cross-section of the detachment prevention ring (220), that is, the diameter of the hollow space formed inside the detachment prevention ring (220), is formed to be less than the diameter of the cross-section of the portion of the screw head (120).

Accordingly, the screw member (100) can also be prevented from moving in the direction toward the coupled spine, i.e., in the direction opposite to the load (R).

As a result, the pedicle screw assembly (10) according to the embodiment of the present invention can prevent movement in the axial direction by the screw protrusion (140) while the screw member (100) is rotatably coupled to another configuration.

Meanwhile, in the illustrated embodiment, the load support nut (400) is engaged until the load (R) comes into contact with the anti-separation body (210) and the screw projection (140) engaged therewith. As described above, the engagement distance of the load support nut (400) can be adjusted. When the engagement position of the load (R) needs to be adjusted further rearward, the load support nut (400) can be accommodated in the support nut receiving space (340) only to the distance that allows the load (R) and the anti-separation body (210) or the screw projection (140) to be separated.

That is, by changing the position of the load support nut (400), the coupling position of the load (R) can be adjusted without changing the insertion length of the screw body (110). Accordingly, insertion and withdrawal of the screw member (100) coupled to the spine is not required, so the pain of the subject can be reduced, the treatment efficiency can be improved, and the invasion can be minimized.

Although the embodiments of the present invention have been described, the spirit of the present invention is not limited to the embodiments presented in this specification, and those skilled in the art who understand the spirit of the present invention will be able to easily suggest other embodiments by adding, changing, deleting, or adding components within the scope of the same spirit, but this will also be considered to fall within the spirit of the present invention.

10: Pedicle screw assembly 100: Screw member

110: Screw body 120: Screw head

130: Screw thread 140: Screw projection

150: Screw hollow 151: First screw hollow

152: Second screw hollow 200: Anti-separation member

210: Anti-separation body 211: Anti-separation hollow

212: Screw head support surface 213: Screw projection support surface

220: Anti-separation ring 221: Anti-separation opening

300: Load support member 310: Member receiving space

320: Ring receiving space 330: Rod receiving space

340: Support nut receiving space 350: Load support thread

360: Load coupling opening 370: Protrusion coupling groove

400: Load support nut 500: Driver support member

510: Driver accommodation space 520: Support member accommodation space

530: Support member joining projection R: rod

d: driver

Claims (13)

A screw member extending in one direction and joined to a pedicle; and Including a detachment prevention member that rotatably supports the screw member, The above screw member, A screw body extending in said one direction and at least partially inserted into said pedicle; A screw head positioned at one end of the extension direction of the screw body and rotatably coupled to the anti-separation member about the one direction as an axis; and A screw protrusion is coupled with the screw head so as to face the screw body with the screw head in between, and is rotatably coupled to the separation prevention member about the one direction as an axis, The above-mentioned detachment prevention member is, A detachment prevention body including a part that rotatably receives the screw head and another part that is connected to the part and rotatably receives the screw projection and is formed to have a cross-sectional area less than the part, Pedicle screw assembly. In the first paragraph, The above anti-separation body is, A detachment-preventing hollow formed penetrating therein along the above-mentioned one direction to rotatably receive the screw head and the screw projection; A screw head support surface that rotatably supports the screw head on one side in one direction; and A screw projection support surface including a screw head support surface continuous with the screw projection support surface and rotatably receiving the screw projection from one side in one direction, Pedicle screw assembly. In the second paragraph, The above screw head is formed such that its outer surface has at least a partial curved surface, The above screw head support surface is formed as a curved surface that extends roundly so as to be convex toward the radial outside. Pedicle screw assembly. In the second paragraph, The above screw projection is, It is formed to have a cross-section having a diameter smaller than the maximum diameter of the cross-section of the above screw head, The above screw projection support surface is formed as a curved surface surrounding the outer periphery of the screw projection. Pedicle screw assembly. In the first paragraph, A load supporting member coupled with the anti-separation member along the above one direction and through which an external load is penetrated along the other direction; and Including a load support nut coupled to the load support member so as to face the anti-separation member with the load interposed therebetween along the above one direction; Pedicle screw assembly. In paragraph 5, The above load supporting member is, A space for receiving a member located inside the member and accommodating the member for preventing detachment; A load receiving space that is connected to the above absence receiving space and receives the load; and Including a support nut receiving space that is connected to the load receiving space and is positioned facing the member receiving space with the load receiving space interposed therebetween. Pedicle screw assembly. In Article 6, The above load supporting member is, A rod support screw thread formed on an inner surface of an outer circumference partially surrounding the support nut receiving space and screw-connected with a screw thread formed on an outer circumference of the load support nut, Pedicle screw assembly. In paragraph 5, The above load supporting member is, It is coupled with the anti-separation member on one side of the above one direction, and is coupled with the load support nut on the other side of the above one direction. The above load is positioned between the above anti-separation member and the load support nut, Pedicle screw assembly. In Article 8, The above load support nut, The load is positioned between a first position for supporting the load so that the load is in close contact with the anti-separation member and a second position for supporting the load so that the load is spaced from the anti-separation member. Pedicle screw assembly. In Article 6, The above load supporting member is, Including a load coupling opening formed through the outer surface radially surrounding the load receiving space and the support nut receiving space to provide an insertion passage for the load. Pedicle screw assembly. In Article 6, The above load supporting member is, Including a ring receiving space that is connected to the above absence receiving space and is arranged to face the load receiving space with the above absence receiving space interposed therebetween, The above-mentioned detachment prevention member is, A detachment prevention ring is coupled with the screw head so as to face the screw projection and is received in the ring receiving space. Pedicle screw assembly. In Article 11, A hollow space is formed inside the above anti-separation ring, and a anti-separation opening is sunken into its outer periphery. The inner diameter of the above anti-separation ring is formed to have a value less than the maximum diameter of the cross-section of the screw head. Pedicle screw assembly. In Article 12, The above anti-separation ring is received in the ring receiving space after being pressed radially inwardly so that the anti-separation opening is at least partially reduced, The anti-separation ring accommodated in the above ring accommodation space is deformed radially inwardly so that the anti-separation opening is at least partially increased. Pedicle screw assembly.

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