TW202112320A - Expandable and adjustable lordosis interbody fusion system - Google Patents

Abstract

A spinal implant device for placement between vertebral bodies includes a housing, at least one screw member in the housing, and at least one drive shaft operably engageable with the screw member. The housing includes a first shell member and a second shell member. At least the first shell member has step tracking comprising a plurality of individual riser members for receiving the at least one screw member. The height of the plurality of individual riser members may change along the step tracking. The drive shaft may be operable to rotate the at least one screw member, causing the at least one screw member to move on the plurality of individual riser members. The at least one screw member comprises an external helical thread having a thickness configured to fit in the gaps between adjacent individual riser members, and is engageable with the first and second shell members, whereby the first and second shell members move relative to each other in response to the rotation of the at least one screw member to effect an expansion of the housing or a contraction of the housing from the expansion by reversing the rotation of the at least one screw member.

Description

Extensible and adjustable lordosis mediator fusion system

The present invention relates to surgical procedures and equipment for treating low back pain.

Lumbar fusion surgery is a surgical method for correcting problems related to the human spine. It usually involves removing damaged discs and bones from between two vertebrae, and inserting bone graft materials that promote bone growth. As the bones grow, the two vertebrae join or fuse together. Fusing the bones together can help stabilize specific areas of the back and help reduce problems related to nerve stimulation at the fusion site. Fusion can be performed in more than one spine segment.

Interbody fusion is a general procedure to remove the nucleus pulposus and/or annulus fibrosus that make up the intervertebral disc at the back problem point, and replace it with a cage that is configured in shape and size to restore the distance between adjacent vertebrae to an appropriate degree. There are different surgical methods for mediator fusion, and it can enter the patient's spine through the abdomen or back. Another surgical method used to accomplish lumbar fusion in a less invasive manner involves accessing the vertebrae through a small incision on the side of the body. This procedure is known as lateral lumbar mediator fusion.

Once the intervertebral disc is removed from the body during the fusion of the lateral lumbar mediators, the surgeon usually forces the different trial implants between the vertebral endplates in a specific area to determine the appropriate size of the implant to maintain the distance between adjacent vertebrae. Another consideration is to maintain the natural angle between the lumbar vertebrae to adapt to the lordosis or natural curvature of the spine. Therefore, when choosing a cage for implantation, the height of the intervertebral disc and the lordosis of the spine must be considered at the same time. The fusion cage of the prior art is generally pre-configured to have top and bottom surfaces that are angled to each other to accommodate the natural curvature of the spine. These values cannot be accurately determined before operation, which is a shortcoming of current procedures. Generally, once the prepared bone graft is of the right size and before inserting it between the vertebral bodies, it is placed in a cage implant.

The current lateral mediator fusion cage device is usually limited to provide height expansion function, but does not have the ability to adjust the lordosis of the spine. In the implementation of trial and error methods to size and fit the mediator fusion cage to the target area of the patient's specific geometric configuration, the patient suffers from major invasive activities. Usually after reaching the required height expansion and final adjustment, the bone graft material is added and packaged into the fusion device.

An embodiment of the device includes an expandable housing composed of opposed housing members. A movable conical screw-like element with an external helical thread is arranged in the housing and operatively engages the top and bottom housing members to push them apart to cause the height of the housing to expand. This function allows the spacing (height) of adjacent vertebrae to be adjusted when they are in place. The cone-shaped members are arranged in a dual configuration such that when the wedge-shaped members are moved in different degrees, the independent engagement of the cone-shaped members along the lateral portions of the top and bottom shells causes an angle inclination with respect to the outer surface of the shell. This function allows adjustment of the angular relationship between adjacent vertebrae and helps the patient to adjust the lordosis of the spine. When the surgeon combines the functions of the device, the device provides an effective in-situ adjustment tool when performing lateral lumbar interbody fusion.

Embodiments of the device also include a track structure in the housing for guiding the tapered external helical threaded member to engage the top and bottom housing members. The rail includes a raised element on each inner surface of the top shell member and the bottom shell member, which when in the retracted position allows interlocking engagement to stabilize the outer shell laterally. As the shell expands, the track area provides space for the storage of bone graft materials. An embodiment may provide an elastic membrane positioned around the housing to prevent the bone graft material from seeping out of the cage, and provide compressive force around the cage to provide structural stability to the housing.

The embodiment of the device also includes a drive shaft for operating the tapered external helical threaded member. The drive shaft allows the surgeon to manipulate the shaft through the use of auxiliary tools. The shaft operably moves the tapered external helical threaded member to control the expansion of the shell and the angle adjustment of the top and bottom shell members to install the interbody fusion device on site . A locking mechanism is provided to prevent the shaft from rotating when the tool is not engaged and after completing the tool operation. The tool also facilitates the insertion of bone graft material into the fusion during in-situ adjustment.

The embodiment of the present invention enables the surgeon to expand the fusion cage and adjust the anteflexion angle of the fusion cage in situ during the operation of the patient, and introduce bone graft material at the surgical site when the device is in place. The embodiments of the present invention thus provide a fusion cage with geometric variability to accommodate different spinal conditions from patient to patient.

The embodiments of the present invention thus provide an interbody support device for lateral lumbar interbody fusion procedures, which combines the functions of adjusting the height expansion of adjacent vertebrae and controlling the angle relationship between the vertebrae of lordosis adjustment. The embodiment of the interbody cage device of the present invention also provides a storage capacity to keep the bone graft material in the interbody cage according to the in-situ adjustment of the height of the intervertebral disc and the lordosis of the spine.

The present invention also provides devices that can be used in environments other than mediator fusion applications. Generally, it can be used to apply the isolation effect between adjacent elements and make the angular relationship between the applied elements variable.

An embodiment of a spinal implant device for placement between vertebral bodies includes a housing; at least one screw member in the housing; and at least one drive shaft operatively engaged with the screw member. The shell includes a first shell member and a second shell member. At least the first shell member has a stepped track including a plurality of individual riser members for receiving the at least one screw member. The height of the plurality of individual riser components can be changed along the stepped track. The drive shaft is operable to rotate the at least one screw member to move the at least one screw member on the plurality of individual riser members. The at least one screw member includes an external helical thread, the thickness of which is configured to fit into the gap between adjacent individual riser members and can be engaged with the first and second shell members, so the first and second shells The members move relative to each other in response to the rotation of the at least one screw member, so that the casing expands or the casing self-expands and contracts by reversing the rotation of the at least one screw member.

An embodiment of a spinal implant device includes a housing; a first pair of screw members and a second pair of screw members in the housing; a first drive shaft operatively engaged with the first pair of screw members And a second drive shaft operatively engaged with the second pair of screw members. The housing includes a first shell member and a second shell member each having a plurality of individual riser members. The plurality of individual riser members of the first and second shell members define a first stepped track path along a first side area of the housing and one of a second side area along the housing The second stepped track route. The height of the plurality of individual riser components changes along the first and second stepped track routes. The first drive shaft is operable to rotate the screw members of the first pair to move the screw members of the first pair along the first stepped track path. The second drive shaft is operable to rotate the screw members of the second pair to move the screw members of the second pair along the second stepped track route. The first and second drive shafts can be operated independently of each other. Each of the first and second pair of screw members includes an external helical thread, the thickness of which is configured to fit into the gap between adjacent individual riser members and can be engaged with the first and second shell members Therefore, the first and second housing members move relative to each other in response to the rotation of the first and/or second pair of screw members, so that the housing expands or by reversing the first and/or second The rotation of the two pairs of screw members causes the housing to expand and contract, wherein when the first and second pairs of screw members are rotated independently of different positions on the first and second stepped track routes, the housing The degree of expansion or contraction of the first side area can be independently adjusted relative to the degree of expansion or contraction of the second side area of the housing.

These and other features of the present invention will be described in more detail in the following paragraphs entitled "Embodiments".

With reference to the drawings, the mediator fusion device is described, shown, and disclosed in accordance with various embodiments (including preferred embodiments) of the present invention. The mediator fusion device 10 is schematically shown in FIG. 1. It is composed of a shell 12 with a top shell 14 and a bottom shell 16. The entire housing may have, for example, a length of 50 mm and a width of 20 mm. The shell material may be composed of suitable materials such as titanium alloy (Ti-6AL-4V), cobalt chromium or polyether ether copper (PEEK). Other materials that can provide sufficient component integrity and have appropriate biocompatibility are also suitable. The inside of the shell is configured to have cascading stepped rails 18 and 20 placed along the sides. As shown in FIG. 2, the stepped track 18 starts from a continuous track step with an increasing height toward the midpoint of the inner surface of the bottom shell 16 and extends to the first end of the bottom shell 16 along with the track. Correspondingly, the stepped track 20 starts from a continuous track step with an increasing height toward the midpoint of the inner surface of the bottom shell 16 and extends along the track to the second opposite end of the bottom shell 16. The stepped track 18 includes dual-track routes 22 and 24, and the stepped track 20 includes dual-track routes 26 and 28, as shown in FIG. 3. The corresponding stepped rails 30 and 32 are arranged on the top shell 14 as shown in FIG. 4. When the device is in a fully compressed state, where the top shell 14 and the bottom shell 16 are adjacent, as shown in FIG. 1, the stepped rail 18 and the stepped rail 30 are joined to each other, and the stepped rail 20 and the stepped rail 32 are joined to each other.

The individual track route includes a series of risers or track steps, which are equally spaced to receive the threads of the tapered external helical threaded member. The tapered outer spiral threaded member provides a wedge-shaped action to isolate the top and bottom shells, thereby increasing the height of the shell and causing the expansion of the vertebral bodies in which the device is placed. As shown in FIG. 4, the orbital route 22 receives the tapered outer helical threaded member 34, the orbital route 24 receives the tapered outer helical threaded member 36, the orbital route 26 receives the tapered outer helical threaded member 38, and the orbital route 28 receives the tapered outer thread. Spiral screw member 40. The orbital route 22 is collinearly aligned with the orbital route 26 so that the advancement of the tapered outer spiral thread members 34 and 38 in the individual orbital routes occurs in a collinear alignment. The thread orientations of the tapered external helical threaded members 34 and 38 are opposite to each other, so that equal rotation thereof will cause movement in opposite directions relative to each other. As shown in FIG. 4, the drive shaft 42 extends along the collinear path of the orbital routes 22 and 26 and passes through the tapered external helical threaded members 34 and 38. The shaft 42 has a square cross-sectional structure and is used to engage and rotate a cone-shaped external helical screw member. As shown in FIG. 5, the central shaft opening 44 of the tapered external helical threaded member is configured to receive and engage the shaft 42. The shaft 42 may include any shape for effectively creating a spline such as a hexagon, and the central shaft opening 44 may include a corresponding configuration for receiving the shape. As the shaft 42 is rotated in a clockwise direction by its end 48, the tapered outer helical threaded members 34 and 38 are rotated and their individual thread orientations cause the screws to advance and separate from each other along the orbital route 22 and the orbital route 26, respectively. On the contrary, as the shaft 42 is rotated in a counterclockwise direction by its end 48, the tapered external helical screw members 34 and 38 respectively advance toward each other along the orbital route 22 and the orbital route 26.

Similarly, the orbital route 24 and the orbital route 28 are collinearly aligned, so that the advancement of the tapered external helical threaded members 36 and 40 in each orbital route occurs in a collinear alignment. The thread orientations of the tapered external helical threaded members 36 and 40 are opposite to each other, so that equal rotation thereof will cause movement in opposite directions relative to each other. In addition, the shaft 46 passes through and engages with the tapered external helical screw members 36 and 40. However, the orientation of the tapered external helical screw members 36 and 40 is opposite to the orientation of the tapered external helical screw members 34 and 38. In this orientation, as the shaft 46 is rotated counterclockwise by its end 50, the tapered outer spiral threaded members 36 and 40 rotate and their individual thread orientations cause the screws to advance to each other along the rail route 24 and the rail route 28, respectively. Separate. In contrast, as the shaft 46 is rotated in a clockwise direction by the end 50 thereof, the tapered external helical screw members 36 and 40 advance toward each other along the orbital route 24 and the orbital route 28, respectively.

As shown in Figure 2, the stepped track is constructed with a series of risers of increasing height. For example, each track route has lifters 52-60, as shown for the stepped track 18 in FIG. 2. As the threads of the tapered external helical threaded member enter the gap between the lifters 52 and 54, the positioning height of the main body of the tapered external helical threaded member in the housing 12 increases as it is supported on the lifters 52 and 54. As the tapered external helical threaded member continues to advance along the track path, its thread passes through the gap between the lifters 52 and 54 and enters the gap between the lifters 54 and 56, so that the tapered external helical threaded member follows within the housing 12 With the support of lifters 54 and 56 for further lifting. As the tapered external helical threaded member continues to advance along the rest of the stepped risers 58 and 60, the positioning height thereof is further increased. As the positioning height of the main body of the tapered outer spiral threaded member increases, the top shell 14 is pushed to move away from the bottom shell 16, as shown in the series of drawings in FIGS. 7A to 7C.

The combined effect of the rotating cone-shaped external helical threaded member causes it to move to the outer end of the individual track route, causing the housing 12 to expand, as shown in FIG. 7. The fully expanded shell is shown in Figure 10. The casing 12 can be reduced by reversing the movement of the cone-shaped external spiral threaded member so that it advances toward the midpoint of the casing along individual orbital routes. The shell will best provide expansion and contraction, resulting in the height of the implant device in this embodiment ranging from about 7.8mm to 16.15mm. The device of this embodiment of the invention may be adapted to provide different expanded diameters.

The pair of tapered external helical thread members in each collinear double-track route can rotate independently of the pair of tapered external helical thread members in the parallel track route. In this configuration, the extent of expansion of the part of the housing on each collinear orbital route is variable to adjust the lordosis effect of the device. As shown in the example shown in FIG. 8, the tapered outer spiral threaded members 36 and 40 respectively have specific extension distances along the track route 24 and the track route 28, so that the top shell 14 and the bottom shell 16 are separated, thereby expanding the outer shell 12. The tapered external helical threaded members 34 and 38 have respectively extended a short distance along the parallel orbital routes 22 and 26, so that part of the top shell and the bottom shell on the orbital routes 22 and 26 are separated to a lower degree. The series of diagrams in FIGS. 15A to 15C show this effect, in which the tapered external helical threaded members 36 and 40 extend and separate from each other in a larger increment, while the tapered external helical threaded members 34 and 38 maintain the same relative distance from each other.

In FIG. 15A, the individual positioning of the group of tapered external helical threaded members 36-40 is almost the same as the group of tapered external helical threaded members 34-38 on its individual tracks. In this positioning, the top shell 14 is substantially parallel to the bottom shell 16. In FIG. 15B, the group of tapered external helical threaded members 36-40 are further away along their equal orbits, and the group of tapered external helical threaded members 34-38 maintain the same position as in FIG. 15A. In this setting, the tapered external helical threaded members 36 and 40 move higher along the advancing side of the top shell 14 relative to the tapered external helical threaded members 34 and 28 along the advancing side of the top shell 14, so that the top shell 14 is inclined with respect to the bottom case 16. In FIG. 15C, the set of tapered external helical threaded members 36-40 moves farther away from the set of tapered external helical threaded members 34-38 along their equal orbits, so that the top shell 14 is more inclined with respect to the bottom shell 16. . Through the independent movement of the individual conical external spiral threaded component groups, the device in this embodiment can achieve a lordosis effect between ^0° and 35 ^°. The device of this embodiment of the invention can be adapted to provide different lordotic tilt sizes.

The structure of the tapered external helical threaded member includes a _{main profile with a minor diameter from Dr1} to _Dr2 , as shown in FIG. 5. The pitch of the thread 33 corresponds to the spacing between the riser elements 52-60 in the track route, as shown in FIG. 4. The thread 33 may have a square profile conforming to the inter-riser member, but other thread shapes may be appropriately used. The increase in the diameter and the tapered aspect ratio of the external helical threaded member makes the top shell 14 and the bottom shell 16 move away from each other as described above. The contact at the top of the risers 52-60 is achieved at the micro-diameter of the helical threaded member.

A thrust bearing is provided to limit the axial movement of the drive shaft in the housing 12. As shown in FIG. 9A, the thrust bearing 62 includes a two-piece yoke structure that cooperates with each other and is press-fitted around the shaft end. The top 64 of the thrust bearing yoke defines an opening for receiving the rounded portion 66 of the shaft end. In FIG. 9C, the square shaft 42 has a rounded portion 66 with a diameter smaller than the square portion of the shaft. The fitting 65 of the thrust bearing engages with the top portion 64 to surround the rounded portion 66 of the drive shaft 42.

The pin elements 68 in the top portion 64 and the bottom portion 65 engage with corresponding holes 69 in the mating piece to provide a press fit of the thrust bearing around the shaft. The journal groove 67 may also be provided in the thrust bearing 62. The shaft 42 may have an annular ridge 63 around the rounded portion 66 thereof, and the annular ridge 63 is received in the journal groove 67, as shown in FIG. 9C. Thrust bearings are provided at both ends of the drive shaft, as shown in Figure 9B. As shown in Figure 6, the thrust bearing limits the axial movement of the drive shaft in the housing.

A safety lock is provided at the proximal end of the device to prevent accidental rotation of the shaft. As shown in FIGS. 12A and 12B, the safety lock member 70 is provided to engage with the proximal ends of the drive shafts 42 and 46. The opening 73 in the safety lock member 70 is configured to have a cross-sectional configuration shape of the drive shaft (see FIG. 13A). A part of the drive shaft has a narrowed rounded structure 71 so that the drive shaft can rotate freely, while the rounded portion of the shaft is aligned with the safety lock member opening 73 (see FIG. 13C). FIG. 12B shows this relationship between the safety lock member 70, the thrust bearing 62, and the drive shafts 42 and 46. When the non-narrowed portion 75 of the shaft is aligned with the safety lock member opening 73, the shaft is prevented from rotating (see FIG. 13B). FIG. 12A shows this relationship between the safety lock member 70, the thrust bearing 62, and the drive shafts 42 and 46. The compression spring 77 may be placed between the thrust bearing 62 and the safety locking member 70 to push the safety locking member backward onto the square portion 75 of the transmission shaft. FIG. 12B shows the lock disengagement when the safety lock member 70 is pushed forward to be out of alignment with the square portion 75 and placed in alignment with the rounded portion 71 of the shafts 42 and 46. The strut 79 may be provided between the safety locking member 70 and the thrust bearing 62, and the compression spring 77 may be positioned thereon. The pillar 79 may be fixedly connected to the safety locking member 70, and an opening may be provided in the thrust bearing 62 through which the pillar 79 can slide. The pillar 79 is provided with a head 81 to restrict the safety lock member 70 from moving backward due to the compression force of the spring 77.

Under the power screw theory, the interaction between the tapered external helical threaded member and the stepped track contributes to self-locking. When considering the variables used to promote self-locking of tapered threaded members, certain factors are relevant. In particular, these factors include the coefficient of friction of the material used (eg Ti-6Al-4V grade 5), the pitch length of the helical thread, and the average diameter of the tapered member. The following equation explains the relationship between the factors that determine whether the tapered external spiral threaded member can be self-locking when it advances along the stepped track:

The above equation determines the torque required to be applied to the drive shaft engaged with the tapered external helical threaded member to expand the shell member. The torque depends on the average diameter of the tapered external helical threaded member, the load applied by the adjacent vertebral body (F), the friction coefficient of the working material (f) and the lead (l), or the spiral thread in this embodiment Pitch. All these factors determine the operating torque required to convert rotation to linear lift to separate the shell members before completing the expansion and lordosis.

The following equation describes the relationship between the factors related to the torque required to reverse the tapered external helical threaded member descending backward along the track:

In this equation, the torque (T _L ) required to reduce the tapered external helical threaded member must be a positive value. When the value (T _L ) is zero or positive, the self-locking of the tapered external spiral threaded member in the stepped track can be achieved. If the value (T _L ) drops to a negative value, the tapered outer spiral threaded member in the stepped track is no longer self-locking. Factors conducive to self-locking include compression load of the vertebral body, insufficient pitch and average diameter of the spiral thread, and insufficient material friction coefficient. The self-locking conditions are shown as follows:

πfd _m >l

Under this condition, it is necessary to select an appropriate combination to make the cone-shaped member have a sufficient average diameter size, and the diameter of the product material in this particular application is greater than the lead or the multiple of the pitch, so that the cone-shaped member can be freely located in the stepped track. locking. According to the average value of the patient lying on the side, the cross-sectional area of the lumbar vertebral body is about 2239 mm ² , and the axial compression force in this area is 86.35N. When Ti-6Al-4V is selected as the working material, the operating torque of the extended shell shell 12 between L4-L5 of the vertebrae is about 1.312 lb-in (0.148 Nm), and the shell shell is made between L4-L5 of the vertebrae The operating torque for 12 contraction is approximately 0.264 lb-in (0.029 Nm).

Alternative embodiments of the expandable shell provide different surgical methods. Figure 11A shows the housing 100 for the surgeon to approach the waist region from the front side of the patient. The overall configuration of the orbital route of this embodiment is similar to that of the device 10, but the drive shaft for moving the tapered external helical threaded member is applied with torque transmitted from the vertical approach. To this end, as shown in FIG. 14, two sets of worm gears 102 and 104 transmit torque to the drive shafts 106 and 108, respectively.

Figure 11B shows the housing 200 for the surgeon to approach the lumbar region from the foramen orientation of the patient. The overall structure of the orbital route of this embodiment is also similar to that of the device 10, but the torque is applied to the drive shaft from the offset approach. To this end, two sets of bevel gears (not shown) can be used to transmit torque to the drive shafts 206 and 208.

The shell 12 is provided with many habitats and open areas on its surface and internal area to accommodate the storage of bone graft materials. The gap between the risers of the cascading stepped rails also provides an area for receiving bone graft material. A membrane can be provided around the outer shell 12 as a supplement to help maintain compression on the top and bottom shells and fixation in the bone graft material. As shown in Figure 10, an extended spring element 78 may be provided to hold the top member 14 and the bottom member 16 together. These elements can also be used to provide initial tension in the direction opposite to the expansion of the fusion device against the mediator. If contact has not yet formed between the outer shell and the vertebral body, the cone-shaped outer spiral threaded member is allowed to climb the riser.

Therefore, this embodiment of the interbody fusion device of the present invention can be expanded to provide support between the vertebral bodies and accommodate the load placed on the area. In addition, the interbody fusion device of the present invention can obtain a structure capable of providing an appropriate lordosis tilt to the affected area. Therefore, the device provides a significant improvement in adjusting the height of the patient's specific intervertebral disc.

The device is provided with tools for operating the mediator fusion device when adjusting it in situ in the human spine. The operating tool 300 is schematically shown in FIG. 16 and includes a handle member 302, a gear housing 304, and torque rod members 306 and 308. The torque rod member is connected to the drive shaft of the expandable housing 12. An embodiment for connecting the torque rod member to the drive shaft of the expandable housing 12 is shown in FIG. 17. In this configuration, the ends 48 and 50 of the drive shafts 42 and 46 may be provided with hexagonal heads. The ends of the torque rod members 306 and 308 may be provided with correspondingly shaped receivers for clamping around the ends 48 and 50.

Inside the gear housing 304, the handle member 302 directly drives the torque rod member 308. The torque bar member 308 is provided with a spur gear member 310 and the torque bar member 306 has a spur gear member 312. The spur gear 312 is slidably received on the torque rod member 306 and can be movably engaged with and disengaged from the spur gear 310. The spur gear lever 314 is engaged with the spur gear 312 to engage and disengage the spur gear 312 and the spur gear 310. When the torque bar member 308 is rotated by the handle 302 and the spur gear 312 is engaged with the spur gear 310, the rotation is transmitted to the torque bar member 306. In this case, the torque rod member 308 rotates the drive shaft 46, while the torque rod member 306 rotates the drive shaft 42 to achieve the expansion of the housing 12, as shown in FIGS. 7A to 7C. By retracting the spur gear lever 314, the spur gear 312 can be disengaged from the spur gear 310, as shown in FIG. 20. When the spur gear 312 is disengaged from the spur gear 310, the rotation of the handle 302 only rotates the torque rod member 308. In this case, the torque rod member 308 only rotates the drive shaft 46, and the drive shaft 42 remains inactive, so that the top member of the housing 12 is inclined, as shown in FIGS. 8 and 15A to 15C, to achieve lordosis of the spine.

To achieve the expansion of the device in the described embodiment, the operator will rotate the handle member 302 clockwise to engage the torque. This applied torque will then engage the compound return spur gear train consisting of spur gear members 310 and 312. This series of gears will then cause the torque rod members 306 and 308 to rotate in opposite directions to each other. The torque bar member 308 (aligned with the handle member 302) will rotate clockwise (to the right), and the torque bar member 306 will rotate counterclockwise (to the left). The torque rod member will then rotate the drive shaft of the interbody fusion device 12 to expand it to the desired height.

To achieve lordosis, the operator moves the spur gear lever 314 back toward the handle member 302. As a result, the spur gear 312 connected to the torque bar member 306 is disengaged from the entire gear train, and thus the torque bar member 306 is disengaged. As a result, the torque rod member 308 will be the only member engaged with the mediator fusion device 12. This will allow the operator to retract the back side of the implant device to produce the desired anterior curvature of the spine.

Referring now to Figures 21 to 29, the lines will describe various embodiments of the spinal implant device according to the present disclosure.

Figure 21 is a perspective top view of an exemplary spinal implant device 400 according to an embodiment of the present disclosure. FIG. 22 is a cross-sectional view of the spinal implant device 400. As shown in FIG. FIG. 23 is a perspective side view of the spinal implant device 400. FIG. FIG. 24 is a front view of the spinal implant device 400. As shown in FIGS. 21-24, the exemplary spinal implant device 400 includes an expandable housing 402; a first pair of screw members 404a, 404b; a second pair of screw members 406a, 406b; and a first pair of screw members 404a, 404b. The first drive shaft 414; and the second drive shaft 416 engaged with the second pair of screw members 406a, 406b.

The housing 402 includes a first or bottom shell member 422 and a second or top shell member 424. The bottom shell member 422 may include a plurality of individual riser members 432 (Figure 23). The top shell member 424 may include a plurality of individual riser members 434 (Figure 23). The plurality of individual riser members 432, 434 of the bottom shell member 422 and the top shell member 424 may define a first stepped track route 436 along the first lateral region 403 of the housing 402 and along the second lateral direction of the housing 402 The area 405 defines a second stepped track route 438 (Figure 22). The height of the plurality of individual riser members 432, 434 may be changed along the first and second stepped track paths 436, 438. For example, the height of the plurality of individual riser members 432, 434 of each of the first and second stepped track routes 436, 438 may increase from the central portion 440 of the stepped track extending from the central portion to the distal side. The first and second pair of screw members 404a, 404b, 406a, 406b may each include an external helical thread, the thickness of which is configured to fit in the gap between adjacent individual riser members (Figures 25 to 26). Describe in more detail.

The first drive shaft 414 is operable to rotate the first pair of spiral members 404a, 404b, thereby moving the first pair of spiral members 404a, 404b on the individual riser members 432, 434 that define the first stepped orbital path 436. The second drive shaft 416 is operable to rotate the second pair of spiral members 406a, 406b, thereby moving the second pair of spiral members 406a, 406b on the individual riser members 432, 434 that define the second stepped orbital path 438. When the first pair and the second pair of spiral members 404a, 404b, 406a, 406b rotate, the bottom shell member 422 and the top shell member 424 can move relative to each other, thereby realizing the expansion of the housing 402 or by the first and/or The rotation of the two pairs of spiral members reversely causes the housing 402 to expand and contract. The first and second drive shafts 414, 416 can operate independently of each other. Therefore, when the first and second sets of screw members 404a, 404b, 406a, 406b rotate independently of different positions on the first and second stepped track routes 436, 438, the first lateral area 403 of the housing 402 The degree of expansion or contraction relative to the degree of expansion or contraction of the second lateral region 405 of the outer shell 402 can be adjusted independently.

The positions of the plurality of individual riser members 432 on the bottom shell member 422 may be arranged to be offset from the positions of the plurality of individual riser members 434 on the top shell member 424, so that when the outer shell 402 is in the contracted configuration, the bottom shell member 422 The plurality of individual riser members 432 of the top shell member 424 may be engaged with the plurality of individual riser members 434 of the top shell member 424.

The first and second pair of screw members 404a, 404b, 406a, 406b may each have a tapered configuration and include external spiral threads, as will be described in more detail below in conjunction with FIGS. 25 to 26. The first pair of screw members 404a, 404b may be arranged or arranged such that the direction of the outer spiral thread of the first pair of first screw member 404a is opposite to the direction of the second pair of screw member 404b. Therefore, when the first drive shaft 414 rotates, the first and second screw members 404a, 404b in the first pair move in opposite directions relative to each other in the first stepped track route 436. Similarly, the second pair of screw members 406a, 406b may be arranged or arranged such that the direction of the outer screw thread of the first screw member 406a of the second pair is oriented with the direction of the outer screw thread of the second screw member 406b of the second pair The orientation is opposite so that when the second drive shaft 416 rotates, the first and second screw members 406a, 406b in the second pair move in opposite directions relative to each other in the second stepped track route 438.

For example, the first and second pair of screw members 404a, 404b, 406a, 406b may be arranged such that when the first drive shaft 414 rotates in a first direction, for example clockwise, the first pair of screw members 404a, 404b Move distally from the central portion 440 along the first stepped orbital route 436, and when the second drive shaft 416 rotates in a second direction opposite to the first direction, such as counterclockwise, the second pair of screw members 406a, 406b moves to the distal side from the central portion 440 along the second stepped orbital route 438, respectively.

Alternatively, the first pair and the second pair of screw members 404a, 404b, 406a, 406b may be arranged such that when the first drive shaft 414 rotates in the first direction, the first pair of screw members 404a, 404b respectively follow the first stepped shape. The orbital route 436 moves distally from the central portion 440, and when the second drive shaft 416 rotates in the same second direction as the first direction, the second pair of screw members 406a, 406b respectively follow the second stepped orbital route 438 from The central part 440 moves distally. Screw with variable root radius and thread thickness

In some embodiments, the first and second pairs of threaded members 404a, 404b, 406a, 406b may be tapered threaded members with variable pitch or root radius and external helical threads with variable thickness. The variable root radius and thread thickness of the screw member can produce a tighter fit between the screw member and the individual lifters of the shell member, which in turn reduces, minimizes or eliminates the implantation device in the starting position, extended position or Undesirable micro-movements between lordosis adjustment positions. The variable root radius and thread thickness of the screw member also allows for a more efficient overall operation when the screw member is for example moved, such as climbing higher and higher individual risers. These features allow for smoother movement and improved mechanical efficiency during the expansion, contraction and lordosis adjustment of the implanted device.

Figure 25 shows an exemplary screw member 450 according to an embodiment of the present disclosure, which can be used as one of the first and second pairs of screw members 404a, 404b, 406a, 406b. As shown, the threaded member 450 includes an external spiral thread 452 wound from the first end surface 454 to the second end surface 456 of the threaded member 450. The screw member 450 may be tapered, for example, the root radius at the first end surface 454 is different from the root radius at the second end surface 456. As used herein, the term “root radius” refers to the size of the screw member 450 measured from the central axis 455 of the screw member 450 perpendicular to the root surface 458 of the screw member 450.

According to an embodiment of the present disclosure, the screw member 450 may have a variable root radius at one end surface or both end surfaces of the screw member 450. As shown in FIG. 25, at the first end surface 454, the screw member 450 may have a first root radius R ₁ and a second root radius R ₂ , wherein R ₁ and R _{2 are} different, for example, R _{1 is} greater than R _{2 in the} figure. At the second end surface 456, the screw member 450 may have a first radius r ₁ and a second radius r ₂ , where r ₁ and r _{2 are} different, for example, r _{1 is} smaller than r _{2 in the} figure. In some embodiments, the root radius of the screw member 450 may change continuously or continuously from the first end surface 454 to the second end surface 456. For example, as shown in FIG. 25, the change from the radius R ₁ to r ₁ can be continuous from the first end surface 454 to the second end surface 456 of the screw member 450, or the change from the radius R ₂ to r ₂ can be from the first end surface of the screw member 450. The end surface 454 is continuous to the second end surface 456. The variable root radius allows the screw member 450 to be located on two individual risers of different heights at the same time.

According to an embodiment of the present disclosure, the external thread 452 of the screw member 450 may have a variable thickness. As shown in FIG. 25, the external thread 452 may have a first thickness T _{1 at the first end surface 454 and a second thickness T 2} at the second end surface 456, where T ₁ and T _{2 are} different, for example as shown in the figure. T _{1 is} greater than T ₂ . According to the embodiment of the present disclosure, the thickness of at least a part of the thread 452 is continuously changed, or continuously or constantly changed. In some preferred embodiments, the thickness of the entire external thread 452 can be continuously changed from the first end surface 454 to the second end surface 456.

Referring to FIG. 26, according to an embodiment of the present disclosure, the threaded side surface of the screw member 450 may be angled. For example, as shown by line 464 in FIG. 26, the side surface 460 of the thread of the screw member 450 may be angled, that is, not perpendicular to the root surface 458 of the screw member 450. According to the embodiment of the present disclosure, a part of the members of the side surface of the riser may also be angled. For example, as shown by line 466 in FIG. 26, a part of the side surface of the lifter member 434 may be angled or chamfered, that is, not perpendicular to the end surface of the lifter 434. The angled side surfaces of the screw member and/or the lifter member can be in contact at different points simultaneously, thereby allowing the screw member to move along the ladder to the track when the torque is applied to the drive shaft to cause the screw member to rotate and advance. Move smoothly.

The characteristics of the screw member 450 provided by the present disclosure enable the screw member in the gap of the individual riser to fit more closely. The tight fit between the screw member and the individual lifters keeps the implant device stable once implanted in the intervertebral body of the patient's spine, and eliminates or reduces unnecessary micro-movements. This will help keep the patient's intervertebral space in the position set by the doctor and promote bone fusion in a better way. The tight fit between the screw member and the individual risers also allows for smooth operation during surgery, while once the implant device is placed in and between the patient’s vertebral body, the surgeon uses surgical instruments such as insertion tools to expand And/or lordosis adjustment implants. It also allows fluid and strong traction during surgery. If the patient's intervertebral disc space collapses, the mechanism can be used to disperse the intervertebral disc space to restore the correct disc height. Extension spring

In some embodiments, an exemplary spinal implant device according to the present disclosure may include one or more extension springs to ensure that the entire implant device remains together. The patient may have severe coronal or sagittal imbalance, and when it is implanted in the patient, uneven force distribution may be applied to the implant device. Uneven force distribution on the internal mechanism can cause the device to detach. Even before implantation in the patient, the device may fall, undergo vibration or rattling, causing the device to disintegrate.

The one or more extension springs provided in the implant device of the present disclosure can hold the top shell member and the bottom shell member together during their fully contracted state, so that in the event of the device being dropped, subjected to vibrations or slaps, All the components in the device remain together.

Extension springs can also be used to maintain opposing forces on the assembly. Once pressure is applied to the top and bottom housing members of the device, the internal mechanisms of the device can perform expansion and/or lordosis adjustments. In order for the mechanism to move efficiently and correctly, it may be necessary to use equal and opposite forces. The extension spring provided in the device of the present disclosure can generate initial tension on the mechanism, thereby allowing the patient's vertebral body to expand and/or perform lordosis adjustment when, for example, the vertebral body of the patient is not in contact with the device.

Once the expansion and/or lordosis adjustment has been performed, the extension spring can also be used to keep the end surface or tip of the individual lifter against the root surface and threads of the screw member. This can ensure that the entire assembly of the device remains together in the extended position or the lordosis adjustment position.

Referring now to FIGS. 21 to 24, the implant device 400 may include a first extension spring 472 that couples the bottom and top shell members 422, 424 and a second extension spring 474 that couples the bottom and top shell members 422, 424. It should be noted that one or more extension springs can be provided in the implantation device and fully perform the function. The first extension spring 472 may be coupled to the top and bottom shell members adjacent to the first stepped track route. The second extension spring 474 may be coupled to the top and bottom shell members adjacent to the second stepped track route. The extension springs 472, 474 may be attached to the top and bottom shell members using any suitable means. For example, the extension springs 472, 474 may have hooks at both ends of the springs that hook into the loops in the bottom and top shell members 422, 424 as shown. The extension springs 472, 474 may also be welded to the top and bottom shell members at the ends of the hooks.

In the case of a surgical operation in which the implant device is inserted into a patient with a large intervertebral disc space anatomy, the extension springs 472, 474 can exert an opposite downward force on the internal mechanism of the implant device 400 to expand or anterior the spine. Adjust the bend until it has touched the patient's vertebral body. In the case of inserting the implant device 400 into a patient with a high degree of lordosis, posterior curvature, or a high degree of coronal imbalance, the extension springs 472, 474 will apply the opposite force by pulling force to keep the mechanism itself in contact with the implant . This will enable doctors to place implants between these unbalanced disc spaces and allow the surgeon to help correct the disc spaces back to normal sagittal and coronal balance. Bearing bite and implant ramp

Returning to Figures 21 to 24, in some preferred embodiments, the spinal implant device 400 may include at least one thrust bearing 480 configured to limit the drive shaft while allowing the drive shaft to rotate or rotate about the longitudinal axis of the drive shaft. Axial and/or lateral movement of 414 and 416. The thrust bearing 480 may be designed to have a slope-like geometry 486, which allows the instrument carrying the bone graft material to be guided into the implant housing 402. This device feature allows for more effective surgical instrumentation of the implanted device, ultimately making the operation more efficient.

Figure 27 is an exploded view of an exemplary thrust bearing 480 in accordance with an embodiment of the present disclosure. As shown, the thrust bearing 480 may have a yoke-like configuration including a first or top 482 and a second or bottom 484. When connected, the top and bottom 482, 484 of the thrust bearing 480 define a pair of openings or bearing positions for receiving or locking the pair of drive shafts 414, 416, such as at the ends of the drive shafts.

The top and bottom 482, 484 of the thrust bearing 480 can be connected by snap fit or press fit provided on the top and bottom, respectively. For example, as shown in Figures 27 to 29, the bottom 484 of the thrust bearing 480 may include a protrusion or guide 486 whose shape and size are configured to be received in the top 482 of the bearing 480 by interference fit. The corresponding notch 488. In some preferred embodiments, the occlusal features in the top and bottom 482, 484 of the bearing 480 can be configured so that when the top and bottom 482, 484 are connected, a portion of the bottom 484 overlaps a portion of the top 482, allowing the top and bottom 482, 484 to overlap. The bottom 482, 484 are more "hooked" or connected, as shown better in Figure 24.

Referring to Fig. 29, the drive shafts 414, 416 may each have a rounded portion 415 that is smaller in diameter than the square of the drive shaft or the remainder. The top and bottom 482, 484 of the thrust bearing 480 can be constructed or dimensioned so that when the top and bottom 482, 484 are connected, the rounded portion 415 of the drive shaft 414, 416 is accommodated in the opening or bearing of the thrust bearing 480 In this position, the drive shafts 414, 416 are prevented from moving axially or laterally, while allowing the drive shafts 414, 416 to rotate or rotate about its longitudinal axis. In some embodiments, the drive shafts 414, 416 may each be provided with an annular ridge 417 in the rounded portion 415. The top and bottom 482, 484 of the thrust bearing 480 may be provided with grooves 483, 485 (better represented in Figures 27 and 28), respectively, so that when the top and bottom 482, 484 are connected, a journal of the bearing is formed. The annular ridge 417 on the drive shaft can be received in the grooves 483, 485 of the bearing 480, thereby providing an improved engagement of the traction shaft with the thrust bearing. The implant device 400 may include at least one or preferably two thrust bearings 480 at one or both ends of the drive shaft.

Still referring to Figures 27-29, the top 482 of the bearing 480 may include a "ramp-like" geometry or flat section 486 between the two curved end sections. The slope-shaped section 486 is combined with the top shell 424 of the shell 402 to provide an easy channel for the surgical instrument carrying bone graft material to be guided into the shell of the implant device 400, as better shown in FIG. 21.

Still referring to FIGS. 27-29, in some embodiments, the thrust bearing 480 may be configured to accommodate certain variations of the drive shafts 414, 416 during the operation of the implant device 400. For example, when the implant device 400 is in a parallel configuration as shown in FIG. 30, the drive shafts 414, 416 are closer. When the implant device 40 is in the lordosis configuration as shown in FIG. 31, the drive shafts 414, 416 are further apart from each other. The bearing opening can be configured as a "slit" rather than a perfect circle to accommodate changes, as shown in Figures 30 to 31.

Various embodiments of the expandable and adjustable lordosis mediator fusion device have been described. It should be understood that the present disclosure is not limited to the specific embodiments described. The aspect described in conjunction with a specific embodiment is not limited to this embodiment, and can be implemented in any other embodiment.

The embodiments are described with reference to the drawings. It should be noted that some drawings are not necessarily drawn to scale. The drawings are only intended to facilitate the description of specific embodiments, and are not intended as detailed description or as a limitation on the scope of the present disclosure. In addition, in the drawings and the description, specific details may be set forth in order to provide a complete understanding of the present disclosure. It will be obvious to those of ordinary skill in the art that some of these specific details may not be used to implement the embodiments of the present disclosure. In other cases, well-known components may not be shown or detailed in order to avoid unnecessarily obscuring the embodiments of the present disclosure.

Unless specifically defined otherwise, all technical and scientific terms used herein have meanings commonly understood by those of ordinary skill in the art. Unless the context clearly indicates otherwise, the singular forms of "a", "an" and "the" used in the specification and the appended application include plural references. Unless the context clearly indicates otherwise, the term "or" refers to a non-exclusive "or."

Those skilled in the art will understand that various other modifications can be made. All these or other changes and modifications are expected by the inventors and are within the scope of the present invention.

6-6: Line 10: Mediator Fusion System 12: Shell 14: top shell 16: bottom shell 18, 20: Stepped track 22, 22, 24, 26, 28: track route 30, 32: Stepped track 33: Thread 34, 36, 38, 40: external screw threaded member 42: drive shaft 44: Central shaft opening 46: axis 48, 50: end 52,54,56: lifter 58,60: stepped lifter 62: Thrust bearing 63: circular ridge 64: top 65: mating parts 66: Rounding Department 67: Journal groove 68: Pin unit 69: Hole 70: Safety locking member 71: Narrowing Rounded Structure 73: Safety lock member opening 75: unnarrowed part 77: Compression spring 78: Extension spring element 79: Pillar 81: head 100: shell 102, 104: Worm gear 106, 108: drive shaft 200: shell 300: operating tools 302: Handle component 304: Gear housing 306, 308: Torque rod components 310: Spur gear member 312: Spur Gear 314: Spur Gear Rod 400: Spinal implant device 402: Expandable Shell 403: first side area 404a, 404b: the first pair of screw components 405: second side area 406a, 406b: the second pair of screw members 414: first drive shaft 415: Rounding Department 416: second drive shaft 417: Annular Ridge 422: bottom shell member 424: top shell component 432,434: Lifter components 436: The first stage-like orbital route 438: Second Stage Orbital Route 440: Central 450: Screw member 452: External spiral thread 454: first end face 455: Central shaft 456: second end face 458: Root Surface 460: side surface 464,466: line 472: first extension spring 474: second extension spring 480: Thrust bearing 482: top 483,485: Slot 484: bottom 486: slope-like geometry/flat section 488: Notch

The embodiments of the present invention are described here with reference to the following drawings. The parts are enlarged and emphasized for the sake of clarity, and are not drawn to scale: Figure 1 is a side elevation view of the side of the expandable housing device. Figure 2 is a perspective view of the bottom section of the expandable shell. Figure 3 is a top plan view of the bottom section of the expandable shell. Figure 4 is a top plan view of the expandable shell device. Figure 5 is a perspective view of a tapered external spiral threaded member. Fig. 5A is a side elevation view of the side of the tapered external spiral threaded member. Fig. 5B is a side elevation view of the front end of the tapered external spiral threaded member. Figure 6 is a cross-sectional view of the device taken along line 6-6 of Figure 1; Figures 7A to 7C are a series of side elevation views of the device when the device is expanded. Figure 8 is a side elevation view of the device showing the expansion of the device to accommodate the lordosis effect. Figure 9A is a perspective expanded view of the thrust bearing used for the drive shaft. Figure 9B is a perspective view of the shaft and thrust bearing of the device. Figure 9C is a top plan view of the cross section of the joint area of the shaft of the device with the thrust bearing. Fig. 10 is a side elevation view of the housing when it is expanded. Figure 11A is a top plan view of another device embodiment. Figure 11B is a top plan view of another device embodiment. Figure 12A is a top plan view of the drive shaft disengaged by the locking mechanism. Figure 12B is a top plan view of the drive shaft engaged by the locking mechanism. Figure 13A is a cross-sectional view of the locking mechanism. Figure 13B is a top plan sectional view of the drive shaft disengaged by the locking mechanism Figure 13C is a top plan sectional view of the drive shaft engaged by the locking mechanism. Fig. 14 is a view taken along the line 14-14 of Fig. 11A. Figures 15A to 15C are a series of side elevation views of the end of the device showing the lordosis effect when the device is expanded. Figure 16 is a perspective view of the operating tool. Figure 17 is a view showing the manner in which the operating tool is attached to the drive shaft of the device. Figure 18 is a separate perspective view of the handle of the operating tool. Figure 19 is a perspective view of the gear in the handle used to operate the engagement of the two drive shafts. Fig. 20 is a perspective view of the gear in the handle for operating the disengagement of a single drive shaft. Figure 21 is a perspective top view of an exemplary spinal implant device according to an embodiment of the present disclosure. Fig. 22 is a cross-sectional view of an exemplary spinal implant device according to an embodiment of the present disclosure. Fig. 23 is a perspective side view of an exemplary spinal implant device according to an embodiment of the present disclosure. Fig. 24 is a cut-away front view of an exemplary spinal implant device according to an embodiment of the present disclosure. Fig. 25 schematically shows the tapered screw member according to the embodiment of the present disclosure. Fig. 26 schematically shows the taper screw member joining the individual riser members according to the embodiment of the present disclosure. Fig. 27 is an exploded view of the thrust bearing member according to the embodiment of the present disclosure. Figure 28 is a cross-sectional view of a thrust bearing member related to other components of an exemplary spinal implant device according to an embodiment of the present disclosure. Figure 29 is a cross-sectional view of a thrust bearing member related to other components of an exemplary spinal implant device according to an embodiment of the present disclosure. Fig. 30 is a perspective view of an exemplary spinal implant device in a parallel configuration according to an embodiment of the present disclosure. Fig. 31 is a perspective view of an exemplary spinal implant device in a lordotic configuration according to an embodiment of the present disclosure.

6-6: Line

10: Mediator Fusion System

12: Shell

14: top shell

16: bottom shell

Claims (19)

A spinal implant device for placement between vertebral bodies, which comprises: A shell At least one screw member in the housing; and At least one drive shaft operatively engaged with the screw member, wherein The housing includes a first shell member and a second shell member, at least the first shell member has a stepped track, which includes a plurality of individual lifter members for receiving the at least one screw member, the plurality of individual lifters The height of the device component can be changed along the stepped track, The drive shaft is operable to rotate the at least one screw member to move the at least one screw member on the plurality of individual riser members, and The at least one screw member includes an external helical thread, the thickness of which is configured to fit into the gap between adjacent individual riser members and can be engaged with the first and second shell members, so the first and second shells The members move relative to each other in response to the rotation of the at least one screw member, so that the casing expands or the casing self-expands and contracts by reversing the rotation of the at least one screw member. The spinal implant device of claim 1, wherein at least a part of the external spiral thread has a continuously changing thickness. The spinal implant device of claim 1, wherein the plurality of individual riser members have angled sides, which are configured to engage with the external screw thread. The spinal implant device of claim 1, wherein the at least one screw member includes a variable root radius. The spinal implant device of claim 4, wherein the at least one screw member is gradually tapered from a first end surface to a second end surface and includes continuously changing from the first end surface to the second end surface of the at least one screw member Root radius. The spinal implant device of claim 5, wherein the outer spiral thread of the at least one screw member has a thickness that continuously changes from the first end surface to the second end surface. The spinal implant device of claim 6, which further comprises at least one extension spring coupled to the first and second shell members at the starting height together and/or during expansion and/or contraction of the shell The first and second shell members are held together. The spinal implant device of claim 1, which further comprises at least one extension spring coupled to the first and second shell members at the starting height together and/or during expansion and/or contraction of the shell The first and second shell members are held together. A spinal implant device for placement between vertebral bodies, which comprises: A shell The first pair of screw members and the second pair of screw members in the housing; A first drive shaft operatively engaged with the screw member of the first pair and a second drive shaft operatively engaged with the screw member of the second pair, wherein The shell includes a first shell member and a second shell member each having a plurality of individual riser members, and the plurality of individual riser members of the first and second shell members define a first shell member along the shell A first stepped track route in a side area and a second stepped track route along a second side area of the housing, the heights of the plurality of individual riser members are along the first and second steps Changes in the orbital route, The first drive shaft is operable to rotate the screw members of the first pair to move the screw members of the first pair along the first stepped track path, and the second drive shaft is operable to rotate the second pair of screw members The screw member makes the screw member of the second pair move along the second stepped track path, the first and second drive shafts can be operated independently of each other, Each of the first and second pair of screw members includes an external helical thread, the thickness of which is configured to fit into the gap between adjacent individual riser members and can be engaged with the first and second shell members Therefore, the first and second housing members move relative to each other in response to the rotation of the first and/or second pair of screw members, so that the housing expands or by reversing the first and/or second The rotation of the two pairs of screw members causes the housing to expand and contract, wherein when the first and second pairs of screw members are rotated independently of different positions on the first and second stepped track routes, the housing The degree of expansion or contraction of the first side area can be independently adjusted relative to the degree of expansion or contraction of the second side area of the housing. The spinal implant device of claim 9, wherein the outer spiral thread of each of the first and second pair of screw members has a continuously changing thickness. The spinal implant device of claim 9, wherein the plurality of individual riser members have angled sides configured to engage with the outer spiral thread of each of the first and second pairs of screw members. The spinal implant device of claim 9, wherein each of the first and second pair of screw members includes a variable root radius. The spinal implant device of claim 9, wherein each of the first and second pairs of screw members is tapered from a first end surface to a second end surface and includes from the first end surface to the second end surface Root radius of continuous change. The spinal implant device of claim 13, wherein the outer spiral thread of each of the first and second pairs of screw members has a thickness that continuously changes from the first end surface to the second end surface. The spinal implant device of claim 14, which further includes at least one extension spring coupled to the first and second shell members, at the starting height together and/or during the adjustment and/or expansion of the shell And/or hold the first and second shell members together during contraction. The spinal implant device of claim 9, which further includes at least one extension spring coupled to the first and second shell members at the starting height together and/or during lordosis adjustment and/or during the lordosis adjustment. The first and second shell members are held together during the expansion and/or contraction of the shell. The spinal implant device of claim 9, which further includes at least one thrust bearing configured to prevent axial and/or lateral movement of the first and second drive shafts, wherein the thrust bearing includes a first part With a second part, it is configured to buckle and fit together to provide a first bearing part to engage the first drive shaft and a second bearing part to engage the second drive shaft. The spinal implant device of claim 17, wherein the second part of the pile-stop bearing member includes an intermediate section between the first and second bearing parts, wherein the intermediate section has a sloped geometric shape , Allowing the instrument carrying the graft material to be guided into the housing. The spinal implant device of claim 17, wherein the first and second bearing parts of the pile-stop bearing member are configured to provide openings, and the degree of the first side area is independently adjusted with respect to the second side area by the slotting And accommodate the space difference between the first and second drive shafts.

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