KR101978163B1 - Anterior cervical plate - Google Patents

Abstract

The present invention relates to an anterior cervical plate used for performing anterior fixation surgery for cervical spine in orthopedic and neurosurgery, body; And at least two bone fixation screw holes formed in the plate body for supporting the head portion of the bone fixation screw.

Description

Anterior cervical plate

The present invention relates to an anterior cervical plate, and more particularly to an anterior cervical plate used for performing anterior fixation surgery for a cervical spine in orthopedic and neurosurgery, .

Cervical disc disease, such as cervical disc disease, cervical disc, cervical fracture and dislocation, and cervical spondylosis myelopathy, Therefore, the use of a cervical spine fixation device has been conventionally used for fixing the cervical spine.

This cervical plate refers to an implant commonly used for the cervical vertebra. It is inserted into the anterior approach of the cervical vertebrae and serves to support two or more cervical vertebrae when fusing the upper and lower cervical vertebrae. In addition, the cervical plate is generally inserted into the cervical vertebra through a bone fixation screw hole formed in the cervical plate, and the head of the bone fixation screw is pressed against the cervical plate to fix it in front of the cervical vertebra. In addition, the cervical plate is curved at an angle similar to that of Lordosis of the cervical vertebrae and has a shape that is in close contact with the anterior cervical vertebrae during surgery.

Also, since the bone fixation screw may be fatal to the patient if it deviates from the cervical plate, a locking element is provided on the cervical fixation device to prevent the bone fixation screw from being dislodged from the cervical plate. Conventional techniques for preventing such deviation include a method in which an escape prevention screw for covering a part of a screw head is used by being coupled to a cervical plate so that the bone fixing screw is not separated from the cervical plate (see US5364399) (See US Pat. No. 6,193,721), and the like using a rotatable locking element that is fixed to the base plate (see US Pat. No. 6,193,721).

However, in the prior art, no consideration has been given to a method for eliminating the foreign body sensation felt by the patient after the operation.

United States Patent US5364399 US Patent US6193721

It is an object of the present invention to provide a front cervical plate that can be easily used by a doctor during surgery and can improve the prognosis of a patient by solving a foreign body sensation felt by a patient after surgery.

According to an aspect of the present invention, And at least two bone fixing screw holes formed in the plate body and supporting a head portion of a bone fixing screw, and a bending allowance portion is formed in a bottom surface of the plate body in a direction perpendicular to the longitudinal direction of the plate body And a cervical plate.

And the reinforcing portion is disposed on the outer periphery of the plate body.

Further, a rounded portion is formed at both ends of the plate body in the longitudinal direction.

Further, the rounded portion is characterized by being formed of two curved surfaces having different radii of curvature.

The radius of curvature of the curved surface located at the upper end of the plate body is represented by R1 and the radius of curvature of the curved surface located at the lower end of the plate body is represented by R2. When the radius is L1 and the shortest distance from the center axis of the bone fixation screw to the end of the plate body is L2, R2 is smaller than R1 and satisfies the following expression.

The depth of the bending allowance is 0.1 to 0.3 times the thickness of the plate body.

And a locking element for locking the bone fixing screw inserted into the bone fixing screw hole, respectively.

The bone fixing screw hole and the locking portion are formed with a seat portion thinner than other portions of the plate body.

The depth of the seat surface portion is not greater than the maximum thickness of the lock portion.

When the curvature between the lock portions located at both ends in the longitudinal direction of the plate body is R3 and the curvatures from the lock portion to the end located at both ends are respectively R4 and R5, R4 and R5 are smaller than R3 .

In addition, R4 and R5 are different from each other.

R 4 and R 5 are 5? R 3 / R 4? 44 and 5? R 3 / R 5? 44.

L3: L4: L5 = 3 to 5: 1: 0.8 to 1.2, where L3, L4 and L5 denote the lengths of the plate bodies in the longitudinal direction of the plate bodies R3, R4 and R5.

The locking unit may include: a rotating body rotatably fixed to the plate body; And a locking blade integrally formed with the rotating body and covering a part of the bone fixing screw hole.

A tool guide hole is formed in the rotating body and a locking tool groove concentric with the tool guide hole is formed around the upper portion of the tool guide hole.

In addition, a locking contact surface is formed on one side of the locking blade, and a locking contact surface is formed continuously with the rotation contact surface, so that the locking portions of the adjacent bone fixing screw holes come into contact with each other And the rotation is restricted in a state in which the lock contact surfaces are in contact with each other.

The locking blade may have a rotation restricting surface continuously formed on the locking contact surface, and the rotation restricting surface may have a larger distance from the central axis of the rotation body than the radius of curvature of the rotation abutting surface.

The locking blade is elastically deformed in a state of being in contact with the upper surface of the plate body, and is restored by an elastic force in a state of covering a part of the bone fixing screw hole.

In addition, a lock start portion is formed on a bottom surface of the lock blade, a body start portion is formed on an upper surface of the plate body, and an engagement portion is formed between the lock start portion and the body start portion .

Further, an end stopper is formed on the plate body to restrict the rotation of the lock portion.

The end stopper is formed with a body end portion, a lock end portion is formed on the bottom surface of the lock wing, and the lock state of the lock portion is maintained by an engagement of the lock end portion and the body end portion, .

In addition, the plate body is formed with a mountain-shaped lock jaw which can ride over the lock wing of the lock portion.

The present invention prevents the patient from feeling a foreign body after the operation.

As a result, the product completeness of the cervical plate can be improved and the reliability from the patient and the practitioner can be increased.

1 is a perspective view of a cervical plate according to a first embodiment of the present invention.
Figure 2 is a plan view of the cervical plate of Figure 1;
Figure 3 is a side view of the cervical plate of Figure 1;
Figure 4 is a bottom view of the cervical plate of Figure 1;
Fig. 5 is a partially enlarged perspective view of the cervical plate of Fig. 1;
Figure 6 is a perspective view of the locking portion of the cervical plate of Figure 1;
7 is a perspective view of the cervical plate locking portion of Fig. 1 operated by a tool.
Fig. 8 is a perspective view of a tool in the cervical plate locking portion of Fig.
Fig. 9 is a partially enlarged sectional view of the cervical plate of Fig. 1 in a locked state. Fig.
FIG. 10 is a partially enlarged plan view and a cross-sectional view of the cervical plate of FIG. 1 in an open state.
FIG. 11 is a partially enlarged plan view and a cross-sectional view of the cervical plate of FIG. 1 in a locked state; FIG.
FIG. 12 is a partially enlarged cross-sectional view showing a state in which a bone fixing screw is inserted in the cervical plate of FIG. 1;
13 is a side view showing the side curvature of the cervical plate of Fig. 1;
14 is a schematic view showing only the curvature in Fig.
15 is a plan view of a cervical plate according to a second embodiment of the present invention.
Figure 16 is a perspective view of the locking portion of the cervical plate of Figure 15;
17 is a plan view and a partially enlarged plan view of a cervical plate according to a third embodiment of the present invention.
18 is a perspective view of the locking portion of the cervical plate of Fig.
19 is a partial plan view of a cervical plate according to a fourth embodiment of the present invention.
20 is a cross-sectional view taken along the line A-A 'in Fig.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals will be used to designate the same or similar elements in the drawings, unless they are indicated on other drawings. Detailed descriptions of known functions and configurations are omitted.

1 to 15, a cervical plate body 100 according to a first embodiment of the present invention will be described. 1 and 2, the cervical plate 100 basically includes a plate body 102 formed to be long in the longitudinal direction, a plate body 102 formed on the plate body 102, At least two bone fixing screw holes 138 for supporting the head 12 and locking elements for locking the bone fixing screws 10 inserted into the bone fixing screw holes 138 112).

The cervical plate 100 may be made of a known material such as titanium or a Co-Cr alloy, but is not limited thereto.

The lock portion 11 is rotatably fixed to the plate body 102 and the reinforcing portion 106 may be disposed on the outer circumference of the plate body 102.

The reinforcing portion 106 has a thickness greater than or equal to that of the plate body 102 and has a curved surface toward the outside to enhance rigidity against stress acting in various directions such as a bending force and a torsion .

A rounded portion 108 may be formed at an end of the plate body 102 in the longitudinal direction. When the cervical plate 100 is installed on the cervical vertebrae, a change from the surface of the cervical vertebrae to the upper surface of the plate body 102 is performed so that the patient can reduce the foreign body sensation felt after the operation It has a gentle shape.

For this, the rounding part 108 preferably has two curved surfaces having different radii of curvature. 12, the radius of curvature of the curved surface located at the upper end of the plate body 102 is R1, the radius of curvature of the curved surface located at the lower end of the plate body 102 is R2, When the radius of the shank of the bone fixing screw 10 inserted into the fixing screw hole 138 is L1 and the shortest distance from the central axis of the bone fixing screw 10 to the end of the plate body 102 is L2 , It is desirable to satisfy the following expression. At this time, R1 is larger than R2.

[Equation 1]

The reinforcing portion 106 and the round portion 108 may be formed at the same time as in Embodiment 1, but they may be arranged selectively.

The bone fixing screw hole 138 and the lock portion 112 may be formed with a seat portion 104 that is thinner than other portions of the plate body 102. The seat portion 104 is provided to the plate body 102 to prevent the lock portion 112 from giving a foreign body feeling to the patient due to its thickness. Therefore, it is ideal that the maximum depth of the seat portion 104 is less than or equal to the maximum thickness of the lock portion 112, considering the overall thickness of the lock portion 112, May be slightly protruding.

A bending allowance portion 116 may be formed on a bottom surface of the plate body 102 in a direction perpendicular to the longitudinal direction of the plate body 102. Generally, the shape of the vertebra is different for each patient, and the cervical plate 100 is often used by bending the patient in accordance with the patient's surgery. At this time, since the cervical plate 100 is made of a material such as titanium, bending is not easy and a large force is required for bending. 3 and 4, the bending margin portion 116 is formed on the bottom surface of the plate body 102 to facilitate the bending of the cervical plate 100 .

However, the bending allowance portion 116 is disposed between two adjacent pairs of bone fixing screw holes 138 when three pairs of bone fixing screw holes 138 are disposed. Particularly, it is preferable to be arranged to avoid the seat portion 104.

The depth of the bending allowance portion 116 is 0.1 to 0.3 times the thickness of the plate body, so that bending can be facilitated without significantly affecting the strength.

The plate body 114 may be provided with a cut-off portion 114 capable of reducing weight, dispersing stress, and acting as a window for confirming a lumbar surface contacting during surgery. The cut-off portion 114 may be formed at a position where the bending allowance portion 116 is formed.

13 and 14, the plate body 102 has a curvature R3 between the locking portions 112 located at both ends in the longitudinal direction of the plate body 102, R4 and R5 are set to be smaller than R3 when the curvatures from the locking portion 112 to the ends are respectively set to be smaller than R3 so that the curved shape of the central region R3 and the whole curved shape of the upper and lower portions Can respond.

In addition, R4 and R5 may be formed differently depending on the curvature of the vertebra. In this case, R4 and R5 can be determined in a range satisfying 5? R3 / R4? 44 and 5? R3 / R5? 44.

L3: L4: L5 = 3 to 5: 1: 1, where L4 is a length along the longitudinal direction of the plate body 102 occupied by R3, R4, and R5, 0.8 to 1.2 can be satisfied.

The locking part 112 includes a rotating body 130 rotatably fixed to the plate body 102 as shown in FIGS. And a locking blade 118 formed integrally with the rotating body 130 and covering a part of the bone fixing screw hole 138.

As shown in FIG. 15, the rotation body 130 is inserted into and fixed to the lock mounting part 144, so that the lock part 112 is rotatable. 15 is a diagram of Embodiment 2, but the lock mounting portion 144 is the same as Embodiment 1 and will be described with reference to FIG. The rotation body 130 may be fixed by passing through the lock mounting part 144 and forming a fixing part 134 by striking an end of the rotation body 130 as shown in FIG.

The locking portions 112 are disposed one by one with respect to one bone fixing screw 10. In addition, two locking portions 112 are arranged so as to be in contact with a pair of bone fixing screw holes 138 arranged in a direction perpendicular to the longitudinal direction of the plate body 102. That is, a locking contact surface 120 concentric with the rotation body 130 is formed on one side of the lock blade 118, and a lock contact surface 122 is formed continuously with the rotation contact surface 120. As a result, the two adjacent lock portions 112 can rotate independently while being in contact with each other at the rotation contact surface 120, and further rotation is restricted when the lock contact surfaces 122 are in contact with each other. Therefore, the lock contact surface (120) from the central axis of the rotating body (130) is formed to have a larger radius of curvature than the rotation contact surface (120) so that the lock portion 122 are formed to be large, and the lock contact surfaces 122 are pressed against each other with a forced force, whereby the frictional force is increased and the lock state can be maintained.

For this restriction of rotation, the locking vane 118 is additionally formed with a rotation stop surface 124 continuous to the locking contact surface 122. The rotation restraining surface 124 may be configured such that the distance from the center axis of the rotating body 130 is not limited to the radius of curvature of the rotating contact surface 120, Is formed larger than the distance.

In other words, by making the side surface of the lock portion 112 have a curved surface shape like the cam, the rotation of the lock portion 112 can be allowed only within a certain range, and the locked state can be maintained.

Since the lock portion 112 is thin, there is a possibility that the tool slips when it is rotated by a tool or the like. A tool guide hole 126 is formed in the inside of the rotary body 130 and a tool guide hole 126 is formed around the upper portion of the tool guide hole 126, A locking tool groove 128 concentric with the locking tool groove 128 can be formed.

5 and 6, the tool 20 includes a tool rod 24, a tool handle 22 coupled to one end of the tool rod 24, A tool tip 26 formed at the other end of the tool guide hole 24 and fastened to the lock tool groove 128 and a tool tip 26 formed to extend from the tool tip hole 26, Guides 28 are formed.

Thus, when inserting the tool 20, the tool tip guide 28 is inserted into the tool guide hole 126 and the tool handle 22 is slightly rotated so that the tool tip 26, When the tool handle 22 is rotated after being fastened to the groove 128, the lock portion 112 can be stably rotated to be opened or locked.

10 and 11, the locking wing 118 is configured such that the wing bottom portion 132 is in contact with the seating surface portion 104, as shown in Figs. 10 and 11, in order to reinforce the locking of the locking portion 112. [ And is resiliently deformed in a state where it is restored by an elastic force in a state of covering a part of the bone fixing screw hole 138. 9, when the end of the locking blade 118 is inserted into the head tool groove 16 formed in the head portion 12 of the bone fixing screw 10, (12), it is possible to prevent the bone fixing screw (10) from being loosened.

In addition, an end stopper 110 may be additionally disposed on the seating surface portion 104. [ The end stopper 110 is a structure such as a protrusion capable of restricting the rotation of the lock part 112, and is disposed in consideration of the rotation locus of the lock part 112. [ In the first embodiment, the end stopper 110 is disposed at a position offset in the longitudinal direction (end direction) of the plate body 102 between a pair of adjacent bone fixing screw holes 138.

As a result, even if an additional force is applied to the lock portion 112, the rotation of the lock portion 112 is restricted by the end stopper 110.

Next, a cervical plate 101 according to a second embodiment of the present invention will be described with reference to Figs. 15 and 16. Fig. The cervical plate 101 is basically the same as the cervical plate 100 according to the first embodiment, but is characterized in that it can maintain the initial position (open state) of the locking part 113. [ The same reference numerals are used for the same parts as those in the first embodiment, and a description thereof will be omitted.

The lock portion 113 is formed such that the lock start portion 142 is formed on the blade bottom portion 132 of the lock blade 118 and the body start portion 142 corresponding to the lock start portion 142 is formed on the seat portion 104, (140) is formed.

One of the body start portion 140 and the lock start portion 142 is provided with a projection and the other is provided with a concave groove. As a result, the initial position (open state) of the lock portion 113 can be maintained unless an external force is applied by the coupling force between the body start portion 140 and the lock start portion 142.

The cervical plate 103 according to the third embodiment of the present invention will be described with reference to Figs. 17 and 18. Fig. The cervical plate 103 is basically the same as the cervical plate 100 according to the second embodiment, but is characterized in that it can maintain the final position (locked state) of the locking part 115. [ The same reference numerals are used for the same parts as those in the first embodiment, and a description thereof will be omitted.

A body end portion 148 is formed in the end stopper 111 and a lock end portion 146 is formed on the bottom surface of the lock wing 118 of the lock portion 115. When the lock portion 115 is rotated by the tool 20, the lock end portion 146 is fastened to the body end portion 148 through the inclined surface of the end stopper 111. Therefore, the locking state of the lock portion 115 can be maintained as long as no external force is applied by the coupling of the body termination portion 148 and the lock termination portion 146.

The cervical plate 105 according to the fourth embodiment of the present invention will be described with reference to Figs. 19 and 20. Fig. The cervical plate 105 is basically the same as the cervical plate 100 according to the first embodiment but is characterized in that it can maintain the initial position (opened state) and the final position (locked state) of the locking part 113 . The same reference numerals are used for the same parts as those in the first embodiment, and a description thereof will be omitted.

To this end, the locking part 112 is the same as that of the first embodiment, and further, the lock jaw 150 is formed on the seating surface part 104 of the plate body 102. The lock jaw 150 is sloped at one side so that the lock wing 118 can ride over and not rotate in the opposite direction when the lock wing 118 completely passes the lock jaw 150, Is formed into a mountain-like shape having a sharp slope or a right angle.

Therefore, when the lock part 112 is opened by the lock part 150, it is necessary to exert a force to slightly elastically deform the lock part 150 in order to pass the lock part 150. Therefore, And the like. In addition, when the locking part 112 completely passes the locking step 150, the locking part 113 is caught by the locking step 150, making it difficult to rotate in the opposite direction. As a result, the locked state can be maintained.

The features of Embodiments 1 to 4 described above may be included in one cervical plate or may be selectively included.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims. It can be understood that

1: vertebra 2: disk
10: bone fixing screw 12: head part
14: threaded portion 16: head tool groove
20: tool 22: tool handle
24: Tool load 26: Tool tip
28: tool tip guide 100,101,103,105: cervical plate
102: plate body 104: concave portion
106 reinforcing portion 108 rounding portion
110, 111: end stoppers 112, 113, 115:
114: Cutoff section 116: Bending margin
118: locking blade 120: rotating contact surface
122: Lock contact surface 124:
126: Tool guide hole 128: Lock tool groove
130: rotating body 132: wing bottom part
134: fixing part 136: concave surface
138: bone fixation screw hole 140: body start portion
142: lock start portion 44: lock mounting portion
146: lock end part 148: body end part
150: Exit jaw

Claims (22)

Plate body; And
At least two bone fixation screw holes formed in the plate body and supporting a head portion of a bone fixation screw,
Wherein a bending allowance portion is formed on a bottom surface of the plate body in a direction perpendicular to the longitudinal direction of the plate body.
The cervical plate according to claim 1, wherein the reinforcing portion is disposed on the outer periphery of the plate body.
The cervical plate according to claim 1, wherein a rounded portion is formed at both end portions in the longitudinal direction of the plate body.
4. The cervical plate according to claim 3, wherein the rounded portion comprises two curved surfaces having different radii of curvature.
The bone plate according to claim 4, wherein a radius of curvature of the curved surface located at the upper end of the plate body is R1, a radius of curvature of the curved surface located at the lower end of the plate body is R2, The radius of the shank of the screw is L1, and the shortest distance from the central axis of the bone fixation screw to the end of the plate body is L2, R2 is smaller than R1 and satisfies the following expression.

2. The cervical plate of claim 1, wherein the depth of the bending margin is 0.1 to 0.3 times the thickness of the plate body.
[2] The cervical plate according to claim 1, further comprising a locking element for locking the bone fixing screw inserted into the bone fixing screw hole.
[8] The cervical plate according to claim 7, wherein the bone fixing screw hole and the locking portion are formed with a seat portion thinner than other portions of the plate body.
9. The cervical plate according to claim 8, wherein the depth of the seating surface portion is equal to or less than a maximum thickness of the locking portion.
[10] The method of claim 7, wherein when the curvature between the lock portions located at both ends in the longitudinal direction of the plate body is R3 and the curvatures from the lock portion to the end located at both ends are R4 and R5, R4 and R5 are smaller than R3 Wherein the cervical plate is a cervical plate.
11. The cervical plate according to claim 10, wherein R4 and R5 are different.
11. The cervical plate according to claim 10, wherein R4 and R5 are 5? R3 / R4? 44 and 5? R3 / R5? 44.
11. The method according to claim 10, wherein L3: L4: L5 = 3: 5: 1: 0.8 to 1.2, where L3, L4 and L5 are the lengths of the plate bodies, Features cervical plate.
8. The apparatus according to claim 7,
A rotating body rotatably fixed to the plate body; And
And a locking blade integrally formed on the rotating body and covering a part of the bone fixing screw hole.
15. The cervical plate according to claim 14, wherein a tool guide hole is formed in the inside of the rotating body, and a locking tool groove concentric with the tool guide hole is formed around an upper portion of the tool guide hole.
[14] The apparatus of claim 14, wherein the lock blade has a rotation contact surface concentric with the rotation body, and the lock contact surface is formed continuously with the rotation contact surface, And the rotation of the cervical plate is restricted in a state in which the lock contact surfaces are in contact with each other.
17. The apparatus of claim 16, wherein the locking wing is formed with a rotation restraint surface continuous to the locking contact surface, wherein the distance from the central axis of the rotation body is greater than the radius of curvature of the rotation abutment surface Cervical plate.
15. The cervical plate according to claim 14, wherein the locking blade is elastically deformed in a state of being in contact with the upper surface of the plate body, and is restored by an elastic force in a state of covering a part of the bone fixing screw hole.
The locking device as claimed in claim 14, wherein a locking start portion is formed on a bottom surface of the locking blade, a body starting portion is formed on an upper surface of the plate body, Wherein the cervical plate is maintained as long as it is not applied.
15. The cervical plate according to claim 14, wherein an end stopper is formed on the plate body to restrict rotation of the lock portion.
21. The locking device according to claim 20, wherein the end stopper is formed with a body end portion, a lock end portion is formed on a bottom surface of the lock wing, and a lock state of the lock portion is exerted by an engagement of the lock end portion and the body end portion Wherein the cervical plate is retained in the cervical plate.
15. The cervical plate according to claim 14, wherein the plate body is formed with a mountain-shaped locking protuberance capable of contacting with the locking wing of the locking part.

Images