Interbody fusion cage with adjustable height

Abstract

Provided is a height-adjustable interbody fusion cage, comprising: a first end plate and a second end plate connected to an adjacent spine body; the far-end moving block can be relatively movably fixed in dovetail grooves formed in the far ends of the first end plate and the second end plate; the near-end moving block can be relatively movably fixed in dovetail grooves formed in the near ends of the first end plate and the second end plate; the adjusting component is rotatably fixed on the near-end moving block, is in threaded connection with the far-end moving block and can adjust the distance between the far end and the near-end moving block; a vertical guide portion disposed on the first and second end plates so as to support a load in the length or width direction of the first and second end plates; the vertical guide portion includes: a pair of first vertical guides extending vertically from the first end plate toward the second end plate and having a cross-section extending in one direction; and a pair of second vertical guides in which long hole grooves into which the first vertical guides are inserted are formed, and which restrict the direction of movement in which the first and second end plates approach each other or are separated from each other by sliding with the first vertical guides.

Description

Technical Field

[0001] The present invention relates to an intervertebral fusion cage with adjustable height, and more particularly to an intervertebral fusion cage which is inserted between vertebrae at a minimum height and can be adjusted in height in the inserted state. Background Art

[0002] The vertebral body is composed of 32 to 35 vertebrae and the intervertebral discs between the vertebrae. It connects the upper skull and the lower pelvis to form the central part of our body.

[0003] From top to bottom, the spine is composed of 7 cervical vertebrae, 12 thoracic vertebrae, 5 lumbar vertebrae, 5 sacral vertebrae, and 3 to 5 coccygeal vertebrae. In adults, 5 sacral vertebrae are fused to form a sacrum, and 3 to 5 coccygeal vertebrae are fused to form a coccyx.

[0004] One of the treatment methods used to treat serious spinal diseases has long been spinal fusion, which is a surgical method of removing intervertebral discs and inserting a fusion cage to replace the intervertebral discs so that adjacent vertebrae can fuse with each other.

[0005] This type of spinal fusion surgery, when performed on the lumbar spine, can be divided into posterior interbody fusion (posterior lumbar interbody fusion, PLIF), transforaminal interbody fusion (transforaminal lumbar interbody fusion, TLIF), lateral interbody fusion (lateral lumbar interbody fusion, LLIF), oblique interbody fusion (oblique lumbar interbody fusion, OLIF), anterior interbody fusion (anterior lumbar interbody fusion, ALIF), etc., according to the insertion direction of the fusion device.

[0006] The method of posterior intervertebral fusion (PLIF) is to make an incision along the center line of the spine, open it until the vertebral body is completely exposed, remove a part of the posterior side of the spine, remove the intervertebral disc, and insert a PLIF fusion device.

[0007] Posterior interbody fusion (PLIF) is the earliest method and is a necessary method for two-level or three-level fusion. However, it has disadvantages such as high probability of adhesion to nerves, ligaments and muscles during the operation, large incision area, long healing time, and large sequelae depending on the individual.

[0008] The PLIF cage is a pair of small cages placed on the left and right sides and is the smallest of all cages used in intervertebral fusion surgeries.

[0009] Transforaminal interbody fusion (TLIF) is a surgical method in which a small incision is made along both sides of the spinal muscles to expose the vertebral body to a minimum, then the spinal joint area is removed in the direction where the neural foramen appears, and the TLIF fusion device is inserted into the intervertebral disc. This surgical method has the advantages of less blood loss and shorter operation time, so it is suitable for single-segment surgery. However, when multiple sites need to be operated on, PLIF surgery should be performed. Most of the TLIF fusion device is arc-shaped, so it is inserted into the vertebral body and rotated so that the protruding part of the TLIF fusion device faces the abdomen. Although the TLIF fusion device is larger than the PLIF fusion device, the support area is smaller than the LLIF fusion device or ALIF fusion device to be mentioned later.

[0010] Anterior interbody fusion (ALIF) has various advantages such as quick recovery after surgery and no need to worry about adhesions, but it has the disadvantage of requiring highly skilled techniques because the front (abdominal) incision is made, the internal organs are moved aside, and the surgery is performed close to the spine. The ALIF cage has the advantage of having the largest support area among all interbody fusion surgeries.

[0011] In order to overcome the shortcomings of ALIF, PLIF, and TLIF, lateral interbody fusion (LLIF) was developed. Lateral interbody fusion is performed by cutting the side, so compared with the previous open back surgery, the distance between the adhesions between the vertebrae can be widened, and the surrounding tissues are almost not damaged. However, there are psoas muscles and peritoneum around the surgical path, so if there is a mistake during the operation, it will cause problems such as thigh muscle paralysis. Although the LLIF fusion device is smaller than the ALIF fusion device, it is smaller than the PLIF fusion device or the TLIF fusion device.

[0012] Compared with this lateral interbody fusion, a safer and more effective surgical method is oblique interbody fusion (oblique lumbar interbody fusion, OLIF) or ATP (anterior psoas fusion). Oblique interbody fusion forms a surgical path in an oblique direction in the ribs, so it has the advantage of being able to perform surgery between the 4th lumbar vertebra (L4) and the 5th lumbar vertebra (L5), which is difficult to perform DLIF surgery due to the psoas major muscle and peritoneum. In addition, the possibility of nerve damage that is a problem with lateral interbody fusion is significantly reduced.

[0013] Conventional intervertebral fusion cages are made of metal materials such as titanium or polymer materials such as PEEK, and are made into a single piece without changes in cross-sectional area or height. Therefore, there are a considerable number of product structures in consideration of the patient's physique, height, race, gender, etc. That is, from the perspective of the manufacturer, there is a burden of having to produce dozens or even hundreds of product lines by combining the three variables of width, length, and height.

[0014] In addition, the distance between the vertebrae of the patient is not a constant distance, so when manufacturing as a single piece, it is necessary to select a suitable height from the existing product line for surgery, which causes a problem that it is not possible to properly respond to each patient.

[0015] In order to solve this problem, various attempts have been made, and height-adjustable intervertebral fusion cages have been developed.

[0016] US Patent Publication No. 2017-0224505 discloses an adjustable height assembly. In detail, the assembly includes: a first and a second support body connected to adjacent vertebral bodies; a first wedge-shaped component that can be relatively movably fixed to a plate inclined portion formed at one end of the first and second support bodies; a second wedge-shaped component that can be relatively movably fixed to a plate inclined portion formed at the other end of the first and second support bodies; an adjustment component that can be rotatably fixed to the second wedge-shaped component and is threadedly coupled to the first wedge-shaped component to adjust the distance between the first wedge-shaped component and the second wedge-shaped component; a U-shaped recessed portion that is formed in a cylindrical shape and is formed on the first support body toward the second support body; an alignment component that is formed in a columnar shape and is formed on the second support body toward the first support body, and limits the movement direction of the first and second support bodies approaching or separating from each other by sliding with the U-shaped recessed portion.

[0017] However, the assembly is a columnar alignment member coupled to a U-shaped recess, so only a portion of the outer surface of the alignment member is surrounded by the U-shaped recess. As a result, there is a problem that the alignment member may be separated from the recess when the assembly is inserted between vertebrae and loads in the width and length directions act strongly on the assembly.

[0018] (Patent Document)

[0019] U.S. Patent Publication No. 2017-0224505 (published on August 10, 2017) Summary of the invention

[0020] (Problem to be solved)

[0021] The present invention is used to solve the above-mentioned problems of the prior art. An object of the present invention is to provide an intervertebral fusion cage which can be adjusted in height in an inserted state and can stably support the movement of a pair of end plates.

[0022] (Methods to solve the problem)

[0023] In one aspect of the present invention, there is provided an intervertebral fusion cage with adjustable height, comprising: a first end plate and a second end plate connected to adjacent vertebral bodies; a distal moving block fixed to a dovetail groove formed at the distal ends of the first end plate and the second end plate so as to be relatively movably fixed; a proximal moving block fixed to a dovetail groove formed at the proximal ends of the first end plate and the second end plate so as to be relatively movably fixed; an adjusting member rotatably fixed to the proximal moving block and threadedly coupled to the distal moving block so as to adjust the distance between the distal moving block and the proximal moving block; and a vertical guide portion disposed on the first end plate and the second end plate so as to support a load in a length direction or a width direction of the first end plate and the second end plate. The vertical guide portion comprises: a pair of first vertical guides extending vertically from the first end plate toward the second end plate and having a cross section extending in one direction; and a pair of second vertical guides formed with a long hole slot inserted into the first vertical guide, and limiting the movement direction of the first end plate and the second end plate to approach or separate from each other by sliding with the first vertical guide.

[0024] According to one embodiment, the first end plate and the second end plate may include a central portion and a pair of extension portions, wherein the pair of extension portions are connected to both sides of the central portion and extend in a distal direction and a proximal direction.

[0025] According to one embodiment, the first end plate and the second end plate may be formed in an H-shape with open distal ends and proximal ends.

[0026] According to an embodiment, the long hole groove of the second vertical guide may be formed to completely surround the outer surface of the first vertical guide.

[0027] According to one embodiment, the first vertical guide may include: a first arc portion; a second arc portion spaced a predetermined distance from the first arc portion; and a pair of horizontal portions connecting the first arc portion and the second arc portion.

[0028] According to one embodiment, the second vertical guide may include: a first arc wall; a second arc wall, which is spaced a predetermined distance from the first arc wall; and a pair of horizontal walls, connecting the first arc wall and the second arc wall; the long hole groove is formed by passing through the first arc wall, the second arc wall and the pair of horizontal walls in a vertical direction.

[0029] According to one embodiment, the first arc portion is connected to the inner side surface of the first arc wall, the second arc portion is connected to the inner side surface of the second arc wall, and the pair of horizontal portions are connected to the inner side surfaces of the pair of horizontal walls.

[0030] According to an embodiment, the first vertical guide may include a concave groove concave in a thickness direction.

[0031] According to one embodiment, marking grooves may be arranged on inner surfaces of the first and second end plates facing each other.

[0032] According to one embodiment, dovetail pieces that are slidably coupled to the dovetail groove may be formed on the upper and lower parts of the distal moving block and the proximal moving block.

[0033] According to an embodiment, an inclined groove for guiding the insertion of the first vertical guide may be formed around the long hole groove.

[0034] (Effects of the Invention)

[0035] According to one aspect of the present invention, the first vertical guide has a cross section extending in one direction, and the second vertical guide is formed into a long hole groove structure corresponding to the first vertical guide, thereby improving the overall mechanical strength of the intervertebral fusion cage.

[0036] The effects of the present invention should be understood to include not only the effects described above but also all effects that can be inferred from the configuration of the invention described in the detailed description of the present invention or the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a perspective view of the intervertebral fusion cage according to the present invention in a state of the lowest height.

[0038] Figure 2 yes Figure 1 A stereoscopic view of the intervertebral fusion cage at its highest height.

[0039] Figure 3 Looking down from above Figure 1 Exploded perspective view of an intervertebral fusion cage.

[0040] Figure 4 Looking down from above Figure 1 A stereoscopic view of a first end plate of an intervertebral fusion cage.

[0041] Figure 5 Looking up from the bottom Figure 1 A stereoscopic view of a first end plate of an intervertebral fusion cage.

[0042] Figure 6 Looking down from above Figure 1 A stereoscopic view of a second end plate of an intervertebral fusion cage.

[0043] Figure 7 Looking up from the bottom Figure 1 A stereoscopic view of a second end plate of an intervertebral fusion cage.

[0044] Figure 8 From the top front Figure 1 Stereoscopic view of the distal translation block of the intervertebral fusion cage.

[0045] Fig. 9 From the upper back Figure 1 Stereoscopic view of the distal translation block of the intervertebral fusion cage.

[0046] Fig.10 yes Figure 1 Front view of the distal translation block of the interbody fusion cage.

[0047] Fig.11 From the top front Figure 1 Stereoscopic view of the proximal translation block of the interbody fusion cage.

[0048] Fig.12 From the upper back Figure 1 Stereoscopic view of the proximal translation block of the interbody fusion cage.

[0049] Fig.13 yes Figure 1 A stereoscopic view of the adjustment components of an intervertebral fusion cage.

[0050] Fig.14 yes Figure 1 Half-section view and partial enlargement of the intervertebral fusion cage.

[0051] Fig.15 yes Figure 1 A side view of the intervertebral fusion cage in its lowest height state and a side view of the intervertebral fusion cage in its highest height state.

[0052] (Explanation of Reference Numerals)

[0053] 1: Intervertebral fusion cage

[0054] 100: First end plate

[0055] 110: First end plate body

[0056] 111: Center

[0057] 112, 113: Extension

[0058] 120: Outside

[0059] 121: Tooth-shaped protrusions

[0060] 130: Inside

[0061] 131: Marker slot

[0062] 140, 141: Opening

[0063] 150: First dovetail groove

[0064] 151: First rail

[0065] 152: Friction reducing groove

[0066] 200: Second end plate

[0067] 210: Second end plate body

[0068] 211: Central Department

[0069] 212, 213: Extension

[0070] 220: Outside

[0071] 221: Tooth-shaped protrusions

[0072] 230: Inside

[0073] 231: Marker slot

[0074] 240, 241: Opening

[0075] 250: Second dovetail groove

[0076] 251: Second rail

[0077] 252: Friction reducing groove

[0078] 300: Remote mobile block

[0079] 310: Insertion

[0080] 320: Connection

[0081] 321: Connecting thread

[0082] 330: First dovetail

[0083] 331: The first protrusion

[0084] 340: Second dovetail

[0085] 341: Second protrusion

[0086] 350: First support surface

[0087] 360: Second support surface

[0088] 400: Near-end mobile block

[0089] 410: Adjustment component hole

[0090] 420: Pin hole

[0091] 421: Pin components

[0092] 430: Third dovetail

[0093] 431: The third protrusion

[0094] 440: Fourth dovetail

[0095] 441: The fourth protrusion

[0096] 450: Fastening part

[0097] 500: Adjustment parts

[0098] 510: Head

[0099] 520: Pin Positioning Department

[0100] 530: Rotating support

[0101] 540: Adjusting screw

[0102] 550: Tool slot

[0103] 600: Vertical guide

[0104] 610: First vertical guide

[0105] 611: First arc part

[0106] 612: Second arc

[0107] 613, 614: Horizontal part

[0108] 615: Depression

[0109] 620: Second vertical guide

[0110] 621: First arc wall

[0111] 622: Second arc wall

[0112] 623, 624: Horizontal wall

[0113] 625: Long hole slot

[0114] 626: Inclined Trough DETAILED DESCRIPTION

[0115] Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention can be implemented in various forms and is not limited to the embodiments described herein. Then, in order to clearly describe the present invention, parts not related to the description are omitted in the accompanying drawings, and similar parts are given the same reference numerals throughout the specification.

[0116] Throughout the specification, when a part is "connected" to another part, this includes not only the case of "direct connection" but also the case of "indirect connection" with other components arranged in between. In addition, when a part "includes" a certain component, unless there is a special record to the contrary, it does not mean that other components are excluded, but other components may also be included.

[0117] The terms including ordinal numbers such as first, second, etc. used in this specification can be used to describe various components or steps, but the components or steps should not be limited to the ordinal numbers. The terms including ordinal numbers should be interpreted as being used only to distinguish one component or step from another component or step.

[0118] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0119] Figure 1 is a stereoscopic view of the intervertebral fusion cage according to the present invention in a state of lowest height; Figure 2 yes Figure 1 A stereoscopic view of the intervertebral fusion cage at its highest height; Figure 3 Looking down from above Figure 1 Exploded perspective view of an intervertebral fusion cage.

[0120] like Figures 1 to 3 As shown, an intervertebral fusion device 1 according to an embodiment of the present invention includes: a first end plate 100 and a second end plate 200, which are roughly arranged to face each other up and down; a distal moving block 300 and a proximal moving block 400, which are arranged between the first end plate 100 and the second end plate 200 and move according to the distance between the first end plate 100 and the second end plate 200; an adjusting component 500, which passes through the proximal moving block 400 to be connected to the distal moving block 300; a vertical guide part 600, which is arranged on the first end plate 100 and the second end plate 200, and thus supports the load in the length direction or width direction of the first end plate 100 and the second end plate 200.

[0121] Figure 4 Looking down from above Figure 1 A three-dimensional view of a first end plate of an intervertebral fusion cage; Figure 5 Looking up from the bottom Figure 1 A stereoscopic view of a first end plate of an intervertebral fusion cage.

[0122] like Figure 4 and Figure 5 As shown, the first end plate 100 has a first end plate body 110 connected to the vertebral body. Specifically, the first end plate body 110 includes a central portion 111 and a pair of extension portions 112, 113, which are formed at both ends of the central portion 111 and extend in both directions perpendicular to the central portion 111.

[0123] The extensions 112 and 113 are formed to pass through the center portion 111 and be spaced a predetermined distance apart in the width direction. The first end plate body 110 may be substantially in the shape of an "H" letter, and openings 140 and 141 are respectively formed at both ends of the first end plate body 110 in the length direction.

[0124] The intervertebral fusion cage 1 is a cage in which a bone forming material (bone graft material) is inserted in an expanded state. However, in the present invention, the openings 140 and 141 are formed, so that the space in which the bone forming material (bone graft material) can be inserted can be increased. In this way, if the insertion space of the bone forming material (bone graft material) is increased, when the intervertebral fusion cage 1 is inserted into the human body, the contact area with the bone is enlarged, which has the effect of making bone fusion excellent.

[0125] A tooth-shaped protrusion 121 may be formed on the outer surface 120 of the first end plate body 110 to prevent separation from the vertebral body.

[0126] Then, first dovetail grooves 150 are formed at both ends of the extensions 112 and 113 of the first end plate body 110 in the length direction. That is, a total of four first dovetail grooves 150 can be formed in the first end plate body 110. The first dovetail piece 330 of the distal moving block 300 and the third dovetail piece 430 of the proximal moving block 400 can be accommodated in the first dovetail groove 150. A pair of first guide rails 151 are arranged on both sides of the first dovetail groove 150 so that the pair of first guide rails 151 face each other. The pair of first guide rails 151 are spaced apart in the width direction of the extensions 112 and 113, and are formed so that the spacing distance gradually decreases toward the ends of the extensions 112 and 113. The first guide rails 151 formed in the distal direction or the proximal direction of the extensions 112 and 113 are all inclined in a direction gradually approaching the center of the first end plate body 110 from the outer surface 120 to the inner surface 130 of the first end plate body 110.

[0127] Preferably, a friction reducing groove 152 that is recessed to a predetermined depth toward the central portion 111 may be formed at the center of the first dovetail groove 150. The left-right width of the friction reducing groove 152 is smaller than the left-right width of the first and third dovetail members 330 and 430, so that the friction reducing groove 152 does not contact the outer surfaces of the first and third dovetail members 330 and 430. That is, the friction reducing groove 152 of the first end plate 100 reduces the friction force generated when the distal moving block 300 or the proximal moving block 400 slides, so that the distal moving block 300 or the proximal moving block 400 can be easily moved.

[0128] Then, a marking groove 131 is arranged on the inner surface 130 of the first end plate 100 facing each other. In detail, the marking groove 131 is formed to be recessed to a predetermined depth in the thickness direction of the first end plate 100 along the width direction of the extension portions 112 and 113 of the first end plate 100. For example, the marking groove 131 may be formed in a semi-cylindrical shape in the width direction. The marking groove 131 serves to facilitate identification of the intervertebral fusion cage 1 during radiographic imaging after the intervertebral fusion cage 1 is inserted into the vertebral body.

[0129] Figure 6 Looking down from above Figure 1A stereoscopic view of a second end plate of an intervertebral fusion cage; Figure 7 Looking up from the bottom Figure 1 A stereoscopic view of a second end plate of an intervertebral fusion cage.

[0130] like Figure 6 and Figure 7 As shown, the second end plate 200 has a second end plate body 210 connected to the vertebral body. Specifically, the second end plate body 210 includes a central portion 211 and extension portions 212, 213, which are formed to extend perpendicularly to the central portion 211 from both ends of the central portion 211 and in both directions.

[0131] The extensions 212 and 213 are formed to pass through the center portion 211 and be spaced a predetermined distance apart in the width direction. The second end plate body 210 may be substantially in an "H" shape, and openings 240 and 241 are respectively formed at both ends of the second end plate body 210 in the length direction.

[0132] As described above, the intervertebral fusion cage 1 is in an expanded state, and a bone forming material (bone graft material) is inserted therein. However, in the present invention, the openings 240 and 241 are formed, so that the space in which the bone forming material (bone graft material) can be inserted can be increased. In this way, if the insertion space of the bone forming material (bone graft material) is increased, when the intervertebral fusion cage 1 is inserted into the human body, the contact area with the bone is enlarged, which has the effect of making bone fusion excellent.

[0133] A tooth-shaped protrusion 221 may be formed on the outer surface 220 of the second end plate body 210 to prevent separation from the vertebral body.

[0134] Then, second dovetail grooves 250 are formed at both ends of the extensions 212 and 213 of the second end plate body 210 in the length direction. That is, a total of four second dovetail grooves 250 can be formed in the second end plate body 210. The second dovetail piece 340 of the distal moving block 300 and the fourth dovetail piece 440 of the proximal moving block 400 can be accommodated in the second dovetail grooves 250. A pair of second guide rails 251 are arranged on both sides of the second dovetail groove 250 so that the pair of second guide rails 251 face each other. The pair of second guide rails 251 are spaced apart in the width direction of the extensions 212 and 213, and are formed so that the spacing distance gradually decreases toward the ends of the extensions 212 and 213. The second guide rails 251 formed in the distal direction and the proximal direction of the extensions 212 and 213 are formed so that all of them are gradually inclined from the outer surface 220 to the inner surface 230 of the second end plate body 210 in a direction approaching the center of the second end plate body 210.

[0135] Preferably, a friction reducing groove 252 that is recessed to a predetermined depth toward the central portion 211 may be formed at the center of the second dovetail groove 250. The left-right width of the friction reducing groove 252 is smaller than the left-right width of the second and fourth dovetail members 340 and 440, so that the friction reducing groove 252 does not contact the outer surface of the second and fourth dovetail members 340 and 440. That is, the friction reducing groove 252 of the second end plate 200 reduces the friction force generated when the distal moving block 300 or the proximal moving block 400 slides, so that the distal moving block 300 or the proximal moving block 400 can be easily moved.

[0136] Then, a marking groove 231 is arranged on the inner surface 230 of the second end plate 200 facing each other. In detail, the marking groove 231 is formed to be recessed to a predetermined depth in the thickness direction of the second end plate 200 along the width direction of the extension portions 212 and 213 of the second end plate 200. For example, the marking groove 231 may be formed in a semi-cylindrical shape in the width direction. The marking groove 231 serves to facilitate identification of the intervertebral fusion cage 1 during radiographic imaging after the intervertebral fusion cage 1 is inserted into the vertebral body.

[0137] The intervertebral fusion cage 1 is inserted into the human body, so its size and shape are greatly restricted. At the same time, it should also have an angle for achieving the basic curvature of the spine (based on the transverse plane, the length direction of the spine, that is, the angle in the sagittal plane direction). Even if there is a height restriction, the size of the adjustment component 500 should have an outer diameter for bearing the load, and the end portion of the first end plate 100 or the second end plate 200 combined with the distal moving block 300 or the proximal moving block 400 is thinned, so it behaves as a weak point when the load is applied, especially the larger the angle, the more serious this phenomenon becomes. In the present invention, in order to eliminate this phenomenon, such as Figures 4 to 7 As shown, the openings 140 and 240 are arranged on the upper and lower sides of the distal end moving block 300, and the openings 141 and 241 are arranged on the upper and lower sides of the proximal end moving block 400, and the thin portions are eliminated in advance.

[0138] Figure 8 From the top front Figure 1 A stereoscopic view of the distal movement block of the intervertebral fusion cage; Fig. 9 From the upper back Figure 1 A stereoscopic view of the distal movement block of the intervertebral fusion cage; Fig.10 yes Figure 1 Front view of the distal translation block of the interbody fusion cage.

[0139] like Figures 8 to 10As shown, in order to facilitate the insertion of the distal moving block 300 between the vertebrae, the insertion portion 310 protrudes in the distal direction and is streamlined. Furthermore, a connecting portion 320 is formed by extending the central portion of the distal moving block 300 in the proximal direction, and a connecting threaded portion 321 with a thread is formed inside the connecting portion 320. Then, a pair of first dovetail pieces 330 corresponding to the first dovetail groove 150 of the first end plate 100 are formed on both sides of the upper portion of the distal moving block 300, and a pair of second dovetail pieces 340 corresponding to the second dovetail groove 250 of the second end plate 200 are formed on both sides of the lower portion of the distal moving block 300.

[0140] A first protrusion 331 corresponding to the first guide rail 151 is formed around the first dovetail 330. If the first dovetail 330 is accommodated in the first dovetail groove 150, the first guide rail 151 and the first protrusion 331 are combined with each other to slide, thereby preventing the distal moving block 300 from being separated from the first end plate 100. A second protrusion 341 corresponding to the second guide rail 251 is formed around the second dovetail 340. If the second dovetail 340 is accommodated in the second dovetail groove 250, the second guide rail 251 and the second protrusion 341 are combined with each other to slide, thereby preventing the distal moving block 300 from being separated from the second end plate 200.

[0141] A first support surface 350 is formed at the center of the upper portion of the distal moving block 300. The first support surface 350 is formed to be parallel to the inner surface 130 of the first end plate body 110 and is in surface contact with the inner surface 130 of the first end plate body 110. A second support surface 360 ​​is formed at the center of the lower portion of the distal moving block 300. The second support surface 360 ​​is formed to be parallel to the inner surface 230 of the second end plate body 210 and is in surface contact with the inner surface 230 of the second end plate body 210. When the intervertebral fusion cage 1 is in the lowest height state, a portion of the inner surface 130 of the first end plate body 110 is in surface contact with the first support surface 350, and a portion of the inner surface 230 of the second end plate body 210 is in surface contact with the second support surface 360, thereby limiting the first end plate 100 and the second end plate 200 from approaching each other.

[0142] Fig.11 From the top front Figure 1 A stereoscopic view of the proximal translation block of the interbody fusion cage; Fig.12 From the upper back Figure 1 Stereoscopic view of the proximal translation block of the interbody fusion cage.

[0143] like Fig.11 and Fig.12As shown, the proximal moving block 400 has an adjustment member hole 410, and the adjustment member 500 is rotatably supported inside the adjustment member hole 410. Then, a pair of third dovetails 430 corresponding to the first dovetail groove 150 of the first end plate 100 are formed at both sides of the upper part of the proximal moving block 400, and a pair of fourth dovetails 440 corresponding to the second dovetail groove 250 of the second end plate 200 are formed at both sides of the lower part of the proximal moving block 400.

[0144] A third protrusion 431 corresponding to the first guide rail 151 is formed around the third dovetail member 430. As the third dovetail member 430 is accommodated in the first dovetail groove 150, the first guide rail 151 and the third protrusion 431 are combined with each other to prevent the proximal moving block 400 from being separated from the first end plate 100. A fourth protrusion 441 corresponding to the second guide rail 251 is formed around the fourth dovetail member 440. As the fourth dovetail member 440 is accommodated in the second dovetail groove 250, the second guide rail 251 and the fourth protrusion 441 are combined with each other to prevent the proximal moving block 400 from being separated from the second end plate 200.

[0145] That is, the first and second end plates 100, 200 according to one embodiment of the present invention are provided with a total of eight dovetail grooves 150, 250 at the ends in the length direction. Since the eight dovetail pieces 330, 340, 430, 440 formed at the distal moving block 300 and the proximal moving block 400 are coupled to the dovetail grooves 150, 250, the intervertebral fusion cage 1 is inserted into the vertebral body, and along with the movement of the body, when the intervertebral fusion cage 1 is subjected to loads not only in the height direction but also in the width direction and the length direction, stress can be effectively dispersed.

[0146] Then, a pin hole 420 for receiving the pin member 421 is formed on the side of the proximal moving block 400. Furthermore, a fastening portion 450 is formed on the side of the proximal moving block 400 to clamp the intervertebral fusion cage 1 by a tool.

[0147] The distal moving block 300 and the proximal moving block 400 are substantially wedge-shaped and are joined with the first end plate 100 and the second end plate 200 to be raised or lowered.

[0148] Fig.13 yes Figure 1 A three-dimensional view of the adjustment components of the intervertebral fusion cage. Fig.13As shown, the adjustment component 500 may roughly have a bolt shape. That is, the adjustment component 500 has a head 510 and an adjustment screw portion 540. The head 510 is located at an opening portion formed in the proximal direction of the adjustment component hole 410, and the adjustment screw portion 540 is threadedly connected to the connecting thread portion 321 of the connecting portion 320 through the adjustment component hole 410. A tool groove 550 that can be connected to a tool s is formed in the head 510. Then, there is a rotation support portion 530 between the head 510 and the adjustment component hole 410, which is connected to the inner wall surface of the adjustment component hole 410 while being rotationally supported. Furthermore, as will be described later Fig.14 As shown, a pin position portion 520 is formed around the rotation support portion 530, and the end of the pin member 421 inserted through the pin hole 420 of the proximal moving block 400 is located in the pin position portion 520. As a result, the adjustment member 500 can be rotated in place.

[0149] like Figures 2 to 7 As shown, the vertical guide portion 600 is composed of a first vertical guide 610 and a second vertical guide 620 , wherein the first vertical guide 610 extends vertically from the inner surface 130 of the first end plate 100 , and the second vertical guide 620 extends vertically from the inner surface 230 of the second end plate 200 and slides with the first vertical guide 610 .

[0150] The first vertical guide 610 may be formed in a columnar shape that vertically protrudes from the center of the inner surface 130 of the extension portion 112, 113 of the first end plate 100 toward the second end plate 200 and has a cross-section extending in one direction. In detail, the outer surface of the first vertical guide 610 includes: a first arc portion 611, which is arranged on the distal end side of the extension portion 112, 113; a second arc portion 612, which is arranged on the proximal end side of the extension portion 112, 113; and a pair of horizontal portions 613, 614, which connect the end of the first arc portion 611 and the end of the second arc portion 612 to each other, and are formed parallel to the length direction of the extension portion 112, 113.

[0151] The second vertical guide 620 is formed in the shape of a column protruding vertically from the center of the inner surface 230 of the extension portion 212, 213 of the second end plate 200 toward the side of the first end plate 100, and a long hole groove 625 is formed in the center of the second vertical guide 620. The long hole groove 625 is formed to pass through from the upper part of the second vertical guide 620 in a vertical direction to the outer surface 220 of the second end plate body 210.

[0152] In detail, the second vertical guide 620 includes: a first arc wall 621, which is arranged on the distal end side of the extensions 212 and 213; a second arc wall 622, which is arranged on the proximal end side of the extensions 212 and 213; and a pair of horizontal walls 623 and 624, which respectively connect the ends of the first arc wall 621 and the second arc wall 622. The pair of horizontal walls 623 and 624 are arranged to be spaced a predetermined distance apart along the width direction of the extensions 212 and 213, so that a long hole groove 625 into which the first vertical guide 610 can be inserted is formed between the first arc wall 621, the second arc wall 622 and the pair of horizontal walls 623 and 624.

[0153] Fig.14 yes Figure 1 Half-section view and partial enlargement of the intervertebral fusion cage.

[0154] like Fig.14 As shown, the first arc portion 611 is formed to correspond to the inner side surface of the first arc wall 621, the second arc portion 612 is formed to correspond to the inner side surface of the second arc wall 622, and a pair of horizontal portions 613 and 614 are formed to correspond to the inner side surfaces of a pair of horizontal walls 623 and 624.

[0155] Therefore, when the first vertical guide 610 is inserted into the second vertical guide 620, the first arc portion 611 is surrounded by the inner side surface of the first arc wall 621, the second arc portion 612 is surrounded by the inner side surface of the second arc wall 622, and the pair of horizontal portions 613 and 614 are surrounded by the inner side surfaces of the pair of horizontal walls 623 and 624. That is, the entire outer surface of the first vertical guide 610 is surrounded by the second vertical guide 620. As a result, the first vertical guide 610 and the second vertical guide 620 can slide stably relative to each other.

[0156] Preferably, an inclined groove 626 inclined inwardly is formed around the long hole groove 625 at the upper part of the first arc wall 621, the second arc wall 622 and a pair of horizontal walls 623, 624, so that when the intervertebral fusion device 1 is assembled or when the height is raised and then lowered again, the first vertical guide 610 is naturally guided to the inside of the long hole groove 625 along the inclined groove 626.

[0157] Preferably, a concave groove 615 that is concave in the thickness direction of the first vertical guide 610 may be formed at the boundaries between the horizontal portions 613, 614 and the first arc portion 611 and between the horizontal portions 613, 614 and the second arc portion 612 of the first vertical guide 610. When the first vertical guide 610 is inserted into the second vertical guide 620, the concave groove 615 does not contact the inner side surfaces of the first arc wall 621, the second arc wall 622, and the horizontal walls 623, 624. That is, the concave groove 615 of the first vertical guide 610 reduces the friction force generated when sliding with the second vertical guide 620, thereby allowing the first vertical guide 610 and the second vertical guide 620 to slide more gently against each other.

[0158] At the same time, the first vertical guide 610 has a cross-section extending in one direction, and the second vertical guide 620 is formed into a long hole groove 625 structure corresponding to the first vertical guide 610, thereby better supporting the force applied in the length direction of the intervertebral fusion cage 1. In other words, the front end stress acting on the first and second vertical guides 610 and 620 is reduced, thereby making the overall mechanical strength of the intervertebral fusion cage 1 excellent.

[0159] Fig.15 yes Figure 1 A side view of the intervertebral fusion cage in its lowest height state and a side view of the intervertebral fusion cage in its highest height state.

[0160] like Fig.15 As shown, by inserting a tool s such as a screwdriver into the tool slot and rotating it in one direction, the proximal moving block 400 and the distal moving block 300 are brought close to each other, resulting in a movement to space the first end plate 100 and the second end plate 200 from each other. Similarly, by inserting a tool s and rotating it in another direction, the distance between the proximal moving block 400 and the distal moving block 300 is spaced, resulting in a movement to close the distance between the first end plate 100 and the second end plate 200.

[0161] The above description of the present invention is for illustrative purposes only, and a person skilled in the art having ordinary knowledge in the technical field to which the present invention belongs may understand that other specific forms may be easily deformed without changing the technical concept or essential features of the present invention. Therefore, the embodiments described above should only be understood as being exemplary in all aspects and not restrictive. For example, each component described in singular form may also be implemented in a dispersed manner, and similarly, components described as dispersed may also be implemented in a combined form.

[0162] The scope of the present invention should be understood to be embodied by the claims, and all changes or modifications derived from the meaning, scope and equivalent concepts of the claims are included in the scope of the present invention.

Claims

1. An intervertebral fusion cage with adjustable height, characterized in that: include: The first end plate and the second end plate are connected to adjacent vertebral bodies; A distal moving block, relatively movably fixed to a dovetail groove formed at the distal ends of the first end plate and the second end plate; A proximal moving block, which is relatively movably fixed to a dovetail groove formed at the proximal ends of the first end plate and the second end plate; An adjusting component, rotatably fixed to the proximal moving block, threadably coupled to the distal moving block, and capable of adjusting the distance between the distal moving block and the proximal moving block; and A vertical guide portion is disposed on the first end plate and the second end plate, so as to support a load in a length direction or a width direction of the first end plate and the second end plate; The vertical guide portion comprises: a pair of first vertical guides extending vertically from the first end plate toward the second end plate and having a cross section extending in one direction; and A pair of second vertical guides are formed with long hole grooves inserted into the first vertical guides, and limit the movement direction of the first end plate and the second end plate approaching or separating from each other by sliding with the first vertical guides.

2. The height-adjustable intervertebral fusion cage according to claim 1, characterized in that: The first end plate and the second end plate include a central portion and a pair of extension portions, The pair of extension portions are connected to both sides of the central portion and extend in the proximal direction and the distal direction.

3. The height-adjustable intervertebral fusion cage according to claim 2, characterized in that: The first end plate and the second end plate are formed in an H shape with open distal ends and proximal ends.

4. The height-adjustable intervertebral fusion cage according to claim 1, characterized in that: The long hole groove of the second vertical guide is formed to completely surround the outer surface of the first vertical guide.

5. The height-adjustable intervertebral fusion cage according to claim 1, characterized in that: The first vertical guide includes: a first arc portion; a second arc portion spaced a predetermined distance from the first arc portion; and a pair of horizontal portions connecting the first arc portion and the second arc portion.

6. The height-adjustable intervertebral fusion cage according to claim 5, characterized in that: The second vertical guide comprises: a first arc wall; a second arc wall spaced a predetermined distance from the first arc wall; and a pair of horizontal walls connecting the first arc wall and the second arc wall; The long hole groove is formed between the first arc wall, the second arc wall and a pair of horizontal walls in a vertical direction.

7. The height-adjustable intervertebral fusion cage according to claim 6, characterized in that: The first arc portion is connected to the inner side surface of the first arc wall. The second arc portion is connected to the inner side surface of the second arc wall. The pair of horizontal portions are in contact with inner side surfaces of the pair of horizontal walls.

8. The height-adjustable intervertebral fusion cage according to claim 7, characterized in that: The first vertical guide includes a concave groove concave in a thickness direction.

9. The height-adjustable intervertebral fusion cage according to claim 1, characterized in that: Marking grooves are arranged on inner surfaces of the first and second end plates that face each other.

10. The height-adjustable intervertebral fusion cage according to claim 1, characterized in that: Dovetail pieces combined with the dovetail groove for sliding are formed on the upper and lower parts of the distal moving block and the proximal moving block.

11. The height-adjustable intervertebral fusion cage according to claim 1, characterized in that: An inclined groove for guiding the insertion of the first vertical guide is formed around the long hole groove.

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