Spinal implants including a flexible screw-locking mechanism

Abstract

The present disclosure includes bone screws, spinal implants, drivers, and assemblies thereof for spinal surgeries, including but not limited to anterior lumbar interbody fusion (ALIF) procedures.

Description

Technical Field

[0001] Cross - Reference to Related Applications This patent application claims the benefit of U.S. Provisional Patent Application No. 63 / 170,531, filed on April 4, 2021, and U.S. Provisional Patent Application No. 63 / 188,277, filed on May 13, 2021. The foregoing applications are incorporated by reference as if fully set forth herein.

[0002] The present disclosure generally relates to bone screws, spinal implants, and instruments useful in spinal implant procedures (including inserters, trial inserters, screw drivers, and removal drivers for bone screws).

Background Art

[0003] The spine is important in human physiology for movement, support, and balance. Spinal injuries can debilitate or be fatal to patients. Even minor irregularities in the spine can cause devastating pain and loss of alignment.

[0004] Surgical procedures are commonly performed to correct problems with displaced, damaged, or degenerated intervertebral discs. Generally, spinal fusion includes removing some or all of the affected or damaged intervertebral disc and inserting one or more intervertebral implants into the resulting disc space. To properly replace damaged or deteriorated spinal vertebrae with artificial implants, it is necessary to consider and understand the stresses inherent in the spine and the biological properties of the body that react to the device.

Summary of the Invention

[0005] In one embodiment, a spinal implant is disclosed herein. The spinal implant comprises: an upper endplate having a first plurality of micropores; a lower endplate having a second plurality of micropores; a central body fixedly positioned between the upper and lower endplates, the central body having a plurality of micropores formed by a support, a first end and a second end facing each other, and two sides; a plurality of fixation openings; each of the plurality of fixation openings being defined by a solid wall extending from the second end of the central body to one of the upper or lower endplates, and one or more solid walls comprising a retaining mechanism configured to hold a bone screw in one or more of the plurality of fixation openings, and a confirmation mechanism (feature) configured to provide tactile feedback to the user when the bone screw is fully inserted into the corresponding fixation opening.

[0006] In some embodiments, the retention mechanism is a passive retention mechanism. In some embodiments, the retention mechanism is a flexible latch having a lip at its proximal end, which allows a bone screw to pass through a corresponding fixation opening in a first direction and is configured to hold the bone screw within the corresponding fixation opening after the proximal end of the bone screw has passed through the lip. In some embodiments, the confirmation mechanism is a thread integrally formed as part of a solid wall, and the bone screw further includes a ridge at the proximal end of the bone screw, and tactile feedback is provided to the user by contact between the ridge and the thread. In some embodiments, the solid walls defining each of the multiple fixation openings are not in contact with each other. In some embodiments, at least one of the solid walls defining a fixation opening is in contact with at least one other solid wall defining a different fixation opening. In some embodiments, at least one solid wall defining a fixation opening is in contact with at least one of the struts in the central body. In some embodiments, the spinal implant further includes an insertion tool engagement mechanism at a second end. In some embodiments, the insertion tool engagement mechanism is in contact with at least one of the solid walls defining the fixed opening. In some embodiments, the insertion tool engagement mechanism is located between at least two solid walls defining the fixed opening and is in contact with at least two solid walls. In some embodiments, one or more of the multiple fixed openings extend from the second end to the upper end plate. In some embodiments, the lip of the flexible latch extends at least toward the upper end plate. In some embodiments, one or more of the multiple fixed openings extend from the second end to the lower end plate. In some embodiments, the lip of the flexible latch extends at least toward the lower end plate. In some embodiments, the flexible latch is integrated with the solid wall or is fixedly mounted to the solid wall. In some embodiments, the flexible latch is fixedly mounted to the central body or is integrated with the central body. In some embodiments, the flexible latch is solid.In some embodiments, the bone screw is configured to extend beyond the upper endplate and be anchored to a first vertebra, or to extend beyond the lower endplate and be anchored to a second vertebra. In some embodiments, the lip is configured to contact the head of the bone screw and hold it in place, thereby holding the bone screw in a fully seated position. In some embodiments, the threads are located at the tip of the corresponding anchoring opening. In some embodiments, the screw is a triple-lead screw. In some embodiments, the threads are configured to engage with a single ridge on the bone screw. In some embodiments, at least a portion of the spinal implant is 3D printed. In some embodiments, the spinal implant is 3D printed. In some embodiments, the spinal implant is made of titanium. In some embodiments, the multiple pores of the central body include a first average pore diameter that is larger than the average pore diameter of a first plurality of micropores or the average pore diameter of a second plurality of micropores. In some embodiments, the insertion tool engagement mechanism is configured to engage with the corresponding engagement mechanism of the inserter. In some embodiments, the engagement mechanism does not contact the solid walls of the multiple fixation openings. In some embodiments, the spinal implant further includes a fusion opening extending from the upper endplate to the lower endplate. In some embodiments, one or more of the multiple fixation openings extend from the lower endplate in a first direction angled by a first acute angle. In some embodiments, one or more of the multiple fixation openings extend from the lower endplate in a second direction angled by a second acute angle. In some embodiments, the first end includes a first height shorter than the second height of the second end.

[0007] In another embodiment, an inserter for inserting a spinal implant is disclosed herein, comprising: an outer shaft comprising an elongated body having a cavity inside and two opposing pins near the tip of the elongated body, the two opposing pins extending inward from the inner surface of the elongated body; and an inner shaft configured to be received within the cavity of the outer shaft, the inner shaft comprising a tip configured to be received into an engagement opening of a spinal implant and a barrel cam element near the tip, the barrel cam element configured to engage with the two opposing pins of the outer shaft; and a thumbwheel screw-coupled to the proximal end of the inner shaft, the thumbwheel being configured to rotate to cause rotation of the barrel cam element, thereby causing the inner shaft to rotate and translate simultaneously with respect to the outer shaft and the spinal implant.

[0008] In some embodiments, the simultaneous rotation and translation of the inner shaft is configured to engage the tip with the engagement opening, thereby locking or unlocking the inserter to the spinal implant. In some embodiments, the outer shaft further includes two posts at the tip of an elongated body, each of which is configured to engage with a lateral engagement slot of the spinal implant. In some embodiments, two opposing pins are located at or near the tip of the barrel cam element in the unlocked position. In some embodiments, two opposing pins are located at or near the proximal end of the barrel cam element in the locked position.

[0009] In yet another embodiment, a driver for removing a bone screw from a spinal implant is disclosed herein. The driver comprises an outer sleeve having a cavity inside; and an inner shaft having a threaded tip; the threaded tip is configured to engage with the threaded head of a bone screw, thereby loosening the bone screw from the spinal implant. The inner shaft is translatable at least in the tip direction relative to the outer sleeve through the cavity of the outer sleeve, and the outer sleeve is configured to flex a flexible latch that latches onto the threaded head of the bone screw.

[0010] In some embodiments, the outer sleeve includes a cannula-shaped hexalobe drive mechanism at or near the tip of the outer sleeve. In some embodiments, the threaded tip of the inner shaft is positioned tipward relative to the tip of the outer sleeve. In some embodiments, the hexalobe drive mechanism is configured to couple to a corresponding feature of the threaded head of the bone screw to facilitate engagement with the bone screw. In some embodiments, the driver is configured to unlock the bone screw when the longitudinal axis of the bone screw is aligned with the longitudinal axis of the driver. In some embodiments, the driver is configured to unlock the bone screw when the longitudinal axis of the bone screw is tilted away from the longitudinal axis of the driver. In some embodiments, the inner shaft further includes a knob at its base end, the knob being rotatable by the user, thereby rotating the inner shaft.

[0011] In yet another embodiment, a driver for removing a bone screw from a spinal implant is disclosed herein. The driver includes: a tip portion having a tip; a drive mechanism located proximal to the tip portion and configured to couple to a corresponding feature of the head of the bone screw to facilitate engagement with the bone screw; and a cam surface located proximal to the drive mechanism. The cam surface is configured to flex outward a flexible latch of the spinal implant that latches onto the head of the bone screw, thereby moving the flexible latch out of the way of interfering with the bone screw.

[0012] In some embodiments, the tip is narrower than the drive mechanism. In some embodiments, the drive mechanism includes a trilobe. In some embodiments, the trilobe is configured to rotate and engage with an undercut of a corresponding feature on the head of the bone screw. In some embodiments, the driver further includes an engagement mechanism configured to attach the tip portion to the handle. In some embodiments, the cam surface is located at least circumferentially on the outer surface of the tip portion.

[0013] In yet another embodiment, a driver for inserting a bone screw into a spinal implant is disclosed herein. The driver includes: an elongated body having a tip portion; a tip portion; a drive mechanism located on the outer surface of the driver proximal to the tip portion and configured to couple to a corresponding feature of the head of the bone screw to facilitate engagement with the bone screw; and a flexible tab extending toward the tip portion and configured to bias outward to hold the bone screw in the driver when the bone screw is loaded into the driver for insertion.

[0014] In some embodiments, the flexible tab includes metal or an alloy. In some embodiments, the flexible tab is at least partially positioned within a groove on the outer surface of the driver. In some embodiments, the drive mechanism includes corresponding trilobe features evenly distributed around the tip portion. In some embodiments, the drive mechanism includes three grooves separating adjacent lobes of the trilobe feature. In some embodiments, the flexible tab is at least partially positioned within one of the three grooves. In some embodiments, the flexible tab is configured to move inward when a bone screw is loaded into the driver. In some embodiments, the flexible tab, in a stationary state, seats radially outward relative to the outer surface of the driver. In some embodiments, the flexible tab includes a proximal portion that is thicker than its tip portion. In some embodiments, at least a portion of the flexible tab is firmly anchored to the elongated body of the driver. In some embodiments, the tip portion is thinner than the drive mechanism. In some embodiments, the corresponding feature of the head of the bone screw includes a trilobe feature. In some embodiments, the trilobe feature is compatible with drivers that include a hexalobular drive mechanism.

[0015] These and other aspects, advantages and notable features of the present invention will become apparent from the following detailed description, in conjunction with the accompanying drawings in which embodiments of the present invention are disclosed. Similar parts throughout the drawings are indicated by the same reference numerals. [Brief explanation of the drawing]

[0016] Novel features of the present invention are described in detail in the appended claims. The features and advantages of the present invention will be better understood by referring to the following detailed description and accompanying drawings illustrating exemplary embodiments in which the principles of the present invention are utilized. [Figure 1] This is a perspective view of a spinal implant according to one embodiment of the present invention, in which multiple bone screws are in a locked position or a fully seated position. [Figure 2A] Figure 1 is a perspective view of the spinal implant according to an embodiment of this specification. [Figure 2B] A perspective view of the spinal implant of FIG. 1 according to an embodiment of the present specification. [Figure 2C] A rear view of the spinal implant of FIG. 1 according to an embodiment of the present invention. [Figure 2D] A front view of the spinal implant of FIG. 1 according to an embodiment of the present invention. [Figure 2E] A top view of the spinal implant of FIG. 1 according to an embodiment of the present invention. [Figure 2F] A side view of the spinal implant of FIG. 1 according to an embodiment of the present invention. [Figure 2G] A perspective view of the frame of the spinal implant of FIG. 1 without a porous structure according to an embodiment of the present invention. [Figure 3A] A perspective view of a spinal implant according to an embodiment of the present invention. [Figure 3B] A top view of a spinal implant according to an embodiment of the present invention. [Figure 3C] A front view of a spinal implant according to an embodiment of the present invention. [Figure 3D] A cross-sectional view of the spinal implant cut along the cutting line C-C of FIG. 3C according to an embodiment of the present invention. [Figure 4A] A view of the inserter disclosed in the present specification according to an embodiment of the present invention. [Figure 4B] A view of the inserter disclosed in the present specification according to an embodiment of the present invention. [Figure 4C] A view of the inserter disclosed in the present specification according to an embodiment of the present invention. [Figure 4D] A view of the inserter disclosed in the present specification according to an embodiment of the present invention. [Figure 4E] A view of the inserter disclosed in the present specification according to an embodiment of the present invention. [Figure 4F] A view of the inserter disclosed in the present specification according to an embodiment of the present invention. [Figure 4G]Exploded view of an inserter according to an embodiment of the present invention, including an outer shaft, an inner shaft, and a thumb wheel. [Figure 4H] It is an enlarged view of the tip of the inserter of FIG. 4G according to an embodiment of the present invention. [Figure 5A] It is a view of the bone screw disclosed in this specification according to an embodiment of the present invention. [Figure 5B] It is a view of the bone screw disclosed in this specification according to an embodiment of the present invention. [Figure 5C] It is a view of the bone screw disclosed in this specification according to an embodiment of the present invention. [Figure 5D] It is a view of the bone screw disclosed in this specification according to an embodiment of the present invention. [Figure 6A] It is a perspective view of a removal driver according to an embodiment of the present invention. [Figure 6B] It is a perspective view of the tip of the removal driver of FIG. 6A according to an embodiment of the present invention. [Figure 7A] It is a perspective view of the tip portion of the outer sleeve and the inner shaft of the removal driver according to an embodiment of the present invention. [Figure 7B] It is a perspective view of the tip portion of the outer sleeve and the inner shaft of the removal driver according to an embodiment of the present invention. [Figure 8] It is a cross-sectional view of a removal driver interacting with a bone screw according to an embodiment of the present invention. [Figure 9A] It is a perspective view showing the state of removing a bone screw from the lock position of a spinal implant using a removal driver according to an embodiment of the present invention. [Figure 9B] It is a side cross-sectional view showing the state of removing a bone screw from the lock position of a spinal implant using a removal driver according to an embodiment of the present invention. [Figure 9C] It is a perspective view showing the state of removing a bone screw from the lock position of a spinal implant using a removal driver according to an embodiment of the present invention. [Figure 9D]This is a side cross-sectional view showing how a bone screw is removed from the locked position of a spinal implant using a removal driver according to one embodiment of the present invention. [Figure 9E] This is a side cross-sectional view showing how a bone screw is removed from the locked position of a spinal implant using a removal driver according to one embodiment of the present invention. [Figure 10A] This is a perspective view of the tip portion of a removal screwdriver according to one embodiment of the present invention. [Figure 10B] This is a perspective view of the tip portion of a removal screwdriver according to one embodiment of the present invention. [Figure 10C] This is a perspective view of the tip portion of a removal screwdriver according to one embodiment of the present invention. [Figure 11A] This is a perspective view showing the engagement of a screwdriver with a bone screw according to one embodiment of the present invention. [Figure 11B] This is a side cross-sectional view showing the engagement of a screwdriver with a bone screw according to one embodiment of the present invention. [Figure 11C] This is a side view showing the engagement of a screwdriver with a bone screw according to one embodiment of the present invention. [Figure 11D] This is a cross-sectional view showing the engagement of a screwdriver with a bone screw according to one embodiment of the present invention. [Figure 12A] Figures 11A and 11B show perspective views of a screwdriver according to one embodiment of the present invention. [Figure 12B] Figures 11A and 11B show perspective views of a screwdriver according to one embodiment of the present invention. [Figure 12C] Figures 11A and 11B are side views of the screwdriver according to one embodiment of the present invention. [Figure 13] This is a side view of an inserter according to one embodiment of the present invention. [Figure 14] This is a perspective view of an implant engaged with a linear inserter according to one embodiment of the present invention. [Figure 15] This is a cross-sectional view of an inserter according to one embodiment of the present invention. [Figure 16A]This is a perspective view of the tip of an inserter in the unlocked position relative to a spinal implant, according to one embodiment of the present invention. [Figure 16B] This is a perspective view of the tip of an inserter in a locked position relative to a spinal implant, according to one embodiment of the present invention. [Figure 16C] This is a tip view of an inserter in the unlocked position relative to a spinal implant, according to one embodiment of the present invention. [Figure 16D] This is a tip view of an inserter in a locked position for a spinal implant, according to one embodiment of the present invention. [Figure 16E] This is a cross-sectional view of an inserter in the unlocked position relative to a spinal implant, according to one embodiment of the present invention. [Figure 16F] This is a cross-sectional view of an inserter in a locked position relative to a spinal implant, according to one embodiment of the present invention. [Figure 17A] This is a perspective view of an embodiment of the detachable T-handle according to an embodiment of the present invention. [Figure 17B] This is a perspective view of an embodiment of the detachable T-handle according to an embodiment of the present invention. [Figure 17C] This is a perspective view of an embodiment of the detachable T-handle according to an embodiment of the present invention. [Figure 18A] This is a perspective view of an inserter according to an embodiment of the present invention. [Figure 18B] This is a perspective view of an inserter according to an embodiment of the present invention. [Figure 19] This is a side view of a laterally inclined inserter engaged with a spinal implant, according to one embodiment of the present invention. [Figure 20] This is a side view of a craniocaudal inclined insertor engaged with a spinal implant, according to one embodiment of the present invention. [Figure 21] This is a perspective view of a slap mallet according to one embodiment of the present invention. [Figure 22] This is a cross-sectional view of a slap mallet according to one embodiment of the present invention. [Figure 23]This is an exploded perspective view of a slap mallet according to one embodiment of the present invention. [Figure 24] This is a side view of a slap mallet according to one embodiment of the present invention. [Figure 25] This is a side view of a slap mallet according to one embodiment of the present invention. [Figure 26] This is a side view of a slap mallet according to one embodiment of the present invention. [Figure 27] This is a side view of a trial inserter according to one embodiment of the present invention. [Figure 28] This is a cross-sectional view of a trial inserter according to one embodiment of the present invention. [Figure 29] This is a side view of a trial inserter without an outer shaft, according to one embodiment of the present invention. [Figure 30] This is a side view of a trial inserter including an outer shaft according to one embodiment of the present invention. [Figure 31] This is a cross-sectional view of a trial inserter according to one embodiment of the present invention. [Figure 32] This is a perspective view of a part of a trial inserter according to one embodiment of the present invention. [Figure 33] This is a perspective view of a part of a trial inserter according to one embodiment of the present invention. [Figure 34] This is a perspective cross-sectional view of a part of a trial inserter according to one embodiment of the present invention. [Modes for carrying out the invention]

[0017] Please note that the drawings in this disclosure are not necessarily to scale. The drawings are intended to illustrate only typical embodiments of this disclosure and should not be considered as limiting the scope of this disclosure. In the drawings, similar reference numerals represent similar elements between drawings.

[0018] overview As disclosed herein, the term “bone screw” is interchangeable with or equivalent to the terms “bone anchor,” “bone fastener,” “fixing screw,” and simply “screw.” “Intervertebral body” is interchangeable with or equivalent to the terms “spinal implant,” “fusion device,” “implant,” or “fusion implant” as used herein.

[0019] As disclosed herein, “base direction” refers to the direction away from the direction in which the element is attached to the object, while “tip direction” refers to the direction opposite to the base direction, in which the element is attached toward the object.

[0020] In some embodiments, bone screws, spinal implants, or other devices are made from one or more biocompatible materials, including but not limited to titanium, stainless steel, cobalt-chromium, ceramics, and / or thermoplastic materials.

[0021] Existing spinal implants, also referred to herein as interbody implants, can be manufactured using additive manufacturing or 3D printing processes and can be made of titanium. Such interbody implants may utilize screw connections to insertion devices. Threading can cause the insertion device to lock in place between the interbody implant, making removal difficult. However, the lagging effect of the threads can be desirable as it eliminates the toggle between the insertion device and the interbody implant. This specification describes implants and devices, including insertion devices, that address these and other challenges.

[0022] Spinal implants This specification discloses spinal implants, also known as fusion devices, intervertebral implants, or fusion implants.

[0023] In some embodiments, the spinal implant is a 3D printed implant that requires no post-processing. This can advantageously include a passive locking mechanism that flexes so as not to obstruct the passage of the screw during insertion. After passing through the flexed latch, small threads on the screw head engage with corresponding threads in the screw pocket, for example, a printed triple-start screw, providing tactile feedback when the screw has passed through the latch and is fully seated. The latch bounces over the screw head, preventing the screw from coming loose if it loosens from the threads in the screw hole.

[0024] In some embodiments, the spinal implant may advantageously include a spring finger mechanism or latch that flexes and springs back to avoid interfering with screw insertion, and continues to capture and hold the screw head. This feature can be fabricated by 3D printing or machining.

[0025] The spinal implant disclosed herein advantageously provides a one-step locking mechanism during screw insertion. Existing locking mechanisms use springs, but conventionally these mechanisms were separate components from the implant. Other locking mechanisms may require two steps, such as cam locks, additional cover plates, or spraying of interfering parts. The flexible latch lock disclosed herein does not require additional devices or locking steps. The locking latch can be 3D printed onto the implant without post-processing, enabling small yet complex geometric shapes that were previously unattainable.

[0026] Referring to Figures 1, 2A-2G, and 3A-3D, the spinal implant 100 disclosed herein includes an upper end plate 101 containing a first plurality of micropores, a lower end plate 102 containing a plurality of micropores, and a central body 103. The central body 103 may be fixedly positioned between the upper end plate 101 and the lower end plate 102, or it may be integral with the upper end plate 101 and the lower end plate 102. The central body 103 may include a plurality of micropores formed by a strut 110. The central body 103 may include a first end 104 and a second end 105 (Figure 2E) opposite each other, two sides 106, and a plurality of fixing openings 107 (Figure 2A) extending from the second end 105 of the central body 103 to either the upper end plate 101 or the lower end plate 102. In the illustrated embodiment, there are four fixed openings 107, but other configurations are also conceivable, as will be understood by those skilled in the art. Two of the fixed openings 107 are angled toward the upper end plate 101, while two of the fixed openings 107 are angled downward toward the lower end plate 102.

[0027] Each fixed opening 107 may include a solid wall 111 surrounding it. One or more solid walls 111 may include a retaining mechanism configured to hold a bone screw 200 (Figure 1) inside one or more of the fixed openings 107. In some embodiments, the retaining mechanism is passive. For example, as shown in Figure 2D, the retaining mechanism is a flexible latch 108 having a lip 109 at its base.

[0028] The solid wall 111 may further include a feature configured to provide tactile feedback to the user when the bone screw 200 is fully inserted into the corresponding fixed opening 107. In some embodiments, the feature is a thread 112 integrally formed as part of the solid wall 111 (Figure 2G). The bone screw 200 may further include a protrusion 212 located on the proximal portion of the bone screw 200, for example, the head 202 (Figure 5B). Contact between the protrusion 212 and the thread 112 (Figure 2G) provides tactile feedback to the user. In some embodiments, a flexible latch 108 is configured to flex to provide tactile feedback as the bone screw 200 passes through the lip 109 and to hold the bone screw 200 in a fully seated position after the head of the bone screw 200 has passed through the lip 109.

[0029] In some embodiments, the solid walls 111 defining each of the multiple fixed openings 107 are independent and do not come into contact with any of the other solid walls 111 defining other fixed openings 107. In other embodiments, at least one solid wall 111 defining a fixed opening 107 is in contact with at least one other solid wall 111 defining a different fixed opening 107 (e.g., Figures 2A and 2D). In some embodiments, at least one solid wall 111 defining a fixed opening 107 is in contact with at least one support column 110 within the central body 103.

[0030] As shown in Figure 1, the spinal fixation implant 100 may include a plurality of fixation openings 107, each opening 107 including a flexible latch 108 integrated with the enclosure of the opening 107. In this particular embodiment, a plurality of bone screws 200, for example, four bone screws 200 (Figure 1), are fixed and fully seated within each fixation opening 107 and locked in place by the flexible latch 108, as shown in Figure 2D. The lip 109 at the proximal end of the flexible latch 108 securely holds the heads 202 of the bone screws 200, thereby preventing the bone screws 200 from retracting from their fully seated position, as shown in Figure 1. In this embodiment, one or more bone screws 200 are anchored to a first vertebra located above the implant 100, and one or more bone screws 200 are anchored to a second vertebra located below the implant 100. In certain embodiments, two bone screws 200 may be anchored to a first vertebra located above the implant 100, and two bone screws 200 may be anchored to a second vertebra located below the implant 100. The first and second vertebrae may or may not be adjacent to each other.

[0031] In some embodiments, one or more fixed openings 107 include a solid wall 111 surrounding at least a portion of the corresponding fixed opening 107. The flexible latch 108 may be integral with the solid wall 111 or may be fixedly attached to the solid wall 111. The solid wall 111 may be made of a non-porous material. As discussed above, the wall 111 may include a discontinuity near the flexible latch 108 so that the latch 108 can move relative to the wall 111 and the rest of the implant 100. In some embodiments, one or more fixed openings 107 may extend from a second fixed opening 107 or through an upper end plate 101, and the lip 109 of the flexible latch 108 associated with such a fixed opening 107 may extend at least toward the upper end plate 101. The fixed opening 107 may extend from a second end 105 to a lower end plate 102 and / or through the lower end plate 102. The lip 109 of the flexible latch 108 can extend at least toward the lower end plate 102.

[0032] In some embodiments, one or more fixed openings 107 extend from the lower end plate 102 in a first direction angled by a first acute angle, while other fixed openings extend from the lower end plate 102 in a second direction angled by a second acute angle.

[0033] The flexible latch 108 may include an elongated flake 108a (Figures 2D, 2E) having a lip 109 at the base end of the flake 108a. The lip 109 of the flexible latch 108, for example, the elongated flake 108a, may extend at least toward the upper end plate 101. The tip of the flake 108a may be fixedly attached to the wall 111 of the opening 107 or formed integrally with the wall 111. Since the wall 111 is integral with the central body 103 of the implant, the flexible latch 108 is fixedly attached to the central body 103 or is integral with the central body 103. The flexible latch 108 may include a solid or non-porous material.

[0034] Referring to Figure 2F, in some embodiments, the first end 104, which may be the rear end when in use, includes a first rear height H1. The second end 105, which may be the front end when in use, includes a second front height H2. In certain embodiments, the rear height H1 of the first end 104 may be less than or shorter than the front height H2 of the second end 105. In certain embodiments, the rear height H1 of the first end 104 may be, for example, 6 mm, 8 mm, 10 mm, or 12 mm. The relationship between the rear height H1 and the front height H2 may result in one of a number of lordosis options, including, for example, 10°, 15°, 20°, 25°, and 30°.

[0035] In some embodiments, the bone screw 200 disclosed herein, once fully inserted, may extend beyond the upper endplate 101 to anchor to a first vertebra, or extend beyond the lower endplate 102 to anchor to a second vertebra. The lip 109 of the flexible latch 108 contacts the head 202 of the bone screw 200 to hold it in place, thereby holding the bone screw 200 in a fully seated position, as seen in Figure 1. Each of the multiple fixing openings 107 may include a thread 112 (Figures 2D, 2G) located on the inner surface of the wall 111. The thread 112 may be configured to provide tactile feedback to the user when the bone screw 200 is inserted into the corresponding fixing opening 107. As shown in Figure 2G, the thread 112 may be located in particular on the tip portion of the corresponding fixing opening 107. In a non-limiting example, the thread 112 may be, for example, a triple-start thread. The thread 112 may be further configured to engage with a single protrusion 212 of the bone screw 200. Details of the bone screw 200 are shown in Figures 5A to 5D, with the protrusion 212 being best shown in Figure 5B.

[0036] In some embodiments, at least a portion of the spinal implant 100 may be formed using additive manufacturing, i.e., the implant 100 may be 3D printed. In some embodiments, the entire spinal implant may be 3D printed. In some embodiments, at least a portion of the spinal implant 100 or the entire spinal implant 100 may be made of titanium.

[0037] The central body 103 (Figures 1 and 2A) may contain a plurality of pores, which may have an average pore diameter, for example, a first average pore diameter. The upper end plate 101 and the lower end plate 102 may each have an average pore diameter that may be a second average pore diameter and a third average pore diameter, respectively. In certain embodiments, the first average pore diameter of the pores in the central body 103 may be larger than the second and third average pore diameters of the pores in the upper end plate 101 and the lower end plate 102. Thus, as can be seen, for example, in Figures 2A to 2C, the central body 103 may contain micropores larger than the micropores that may be present in the upper end plate 101 and / or the lower end plate 102.

[0038] In some embodiments, the implant 100 may further include a fusion opening 114 extending from the upper endplate 101 to the lower endplate 102. The fusion implant (fusion opening) 114 is shown, for example, in Figures 2E, 3A, and 3B. When the implant 100 is placed, for example, between the patient's vertebra L5 and vertebra S1, the fusion of L5 and S1 may occur through the fusion opening 114.

[0039] Referring to Figure 2D, in some embodiments, the spinal implant 100 may include an engagement opening 113a and a pair of engagement slots 113b at the second end 105. The engagement opening 113a may be configured to receive and engage an engagement mechanism 312 of corresponding complementary size and shape on an inserter 300 (Figures 4G, 4H), as further described herein, while the engagement slots 113b may be configured to receive and engage a pair of opposing posts 304 located at the tip of the inserter 300. The engagement opening 113 may be configured to receive the engagement mechanism 312 when the engagement mechanism 312 is in a first orientation and may include an undercut to prevent the engagement mechanism 312 from being withdrawn from the engagement opening 113a after the engagement mechanism 312 has been rotated by a certain amount, for example, about 90°. In some embodiments, the shape of the engagement opening 113a may be substantially rectangular.

[0040] The engagement opening 113a may be in contact with at least one of the solid walls 111 that define the fixed opening 107. The engagement opening 113a may be positioned between two solid walls 111, each defining the fixed opening 107. In some embodiments, the engagement opening 113a, for example, the wall of the engagement opening 113a, or at least a portion of the wall, may be located between at least two solid walls 111, each defining the fixed opening 107, and in contact with those at least two solid walls 111. In some embodiments, the engagement opening 113a is located on or near the midline of the implant 100, and thus is at substantially equal distance to the two sides 106 of the implant 100.

[0041] Implant inserter As described above, an inserter 300 configured to insert a spinal fusion implant 100 into a position within the patient's body is disclosed herein.

[0042] Referring to Figures 4A to 4G in general, the inserter 300 includes an outer shaft 301 having an elongated body with a cavity or lumen inside, and an inner shaft 310 positioned within the cavity of the outer shaft 301. The proximal end of the outer shaft 301 is coupled to a handle to assist in operating the device.

[0043] The outer shaft 301 may include a pair of opposing pins 303 located within it, near the tip of the elongated body 302. The opposing pins 303 may extend radially inward from the inner surface of the elongated body 302 and engage with a barrel cam slot 313 (Figure 4G) of the inner shaft 310, configured to rotate and translate the inner shaft 310 simultaneously with a single input. An input can be provided using a threaded thumbwheel 320 located at and coupled to the base end of the inner shaft 310. The two opposing pins 303 may be located at or near the tip of the barrel cam slot 313 in the unlocked position. The two opposing pins 303 may be located at or near the base end of the barrel cam slot 313 in the locked position.

[0044] The engagement mechanism 312 may be located at the tip 311 of the inner shaft 310. The engagement mechanism 312 is configured to be inserted into the engagement opening 113a of the implant 100 in a keyed configuration. After inserting the engagement mechanism 312 into the engagement opening 113a, the thumbwheel 320 is rotated to delay and hold the implant 100. The inserter 300 disclosed herein can achieve this movement with a slim profile that allows for an internal mounting point to the implant 100. This slim profile further facilitates the insertion or removal of the screw 200 using the drivers 500 and 400, respectively, while the inserter 300 remains engaged with the implant 100.

[0045] In some embodiments, the inserter 300 disclosed herein utilizes a barrel-cam mechanism to translate and rotate the inner shaft 310 with a single input. This design achieves the lagging effect of threads without using threaded connections. The inserter 300 disclosed herein advantageously achieves the lagging effect without using threads. The inserter 300 disclosed herein advantageously eliminates the problem of adhesion (e.g., cold welding) at the interface between the inserter 300 and the intervertebral body 100 in situ. Furthermore, existing 3D-printed titanium intervertebral bodies 100 may require post-processing of threaded inserter mechanisms after the printing process. By removing threads from the intervertebral body 100, the number of process steps is reduced.

[0046] The thumbwheel 320 may be screw-coupled to the base end of the inner shaft 310. As described herein, the thumbwheel 320 may be configured to rotate, causing rotation of the barrel cam element 313, thereby simultaneously causing rotation and translation of the inner shaft 310 relative to the outer shaft 302 and the spinal implant 100. In some embodiments, the rotation of the thumbwheel 320 simultaneously causes rotation and translation of the inner shaft 310 relative to the outer shaft 302, which may cause engagement or disengagement of the engagement mechanism 312 of the tip 311 and the inner shaft 310 with the engagement opening 113a of the implant 100, thereby locking or unlocking the inserter 300 relative to the spinal implant 100.

[0047] In some embodiments, the outer shaft 301 may include two posts 304 at the tip of an elongated body 302. The posts 304 are best shown in Figures 4G–4H. Each of the two posts 304 may be configured to engage with a lateral engagement slot 113b of the spinal implant 100 (see, for example, Figures 3C–3D) to provide further engagement.

[0048] bone screws Referring to Figures 5A to 5D in general, a bone screw 200 is disclosed herein, which is configured to be inserted between vertebral bodies or into an implant 100 and anchored to a vertebra. The bone screw 200 may include a screw head 202 including a keyed drive mechanism 203 configured to engage or couple mating with a drive mechanism 403 of a driver, such as a removal driver 400, which is further described herein. For example, the mechanism 203 may have a shape and dimensions that provide a complementary mating with the drive mechanism 403 of the removal driver 400. In some embodiments, the bone screw head 202 may include a cavity 201, and the mechanism 203 may extend tipwise into the cavity 201 from the inner surface of the bone screw head 202 surrounding the cavity 201.

[0049] In some embodiments, the mechanism 203 may include a trilobe shape 205 (Figure 5D) having three lobes extending inward into the cavity 201 of the bone screw head 202. Embodiments of the trilobe 205 of the mechanism 203 may allow for a thicker trilobe 405 on the drive mechanism 403 of the removal driver 400 (e.g., along the longitudinal axis of the screw) (see, for example, Figure 7B), thereby increasing the strength of the driver. In some embodiments, the trilobe 205 on the bone screw 200 may be identical to a standard-sized hexalobular drive with the three lobes removed, as seen in Figure 5D. This may allow for compatibility with a standard hexalobular removal driver of the same size as the screw 200. In some embodiments, the mechanism 203 may further include undercuts 206 located on the tip side of each lobe of the trilobe 205, as shown in Figure 5A. The removal driver 400 can utilize a geometric shape that has a step 406 for capturing the undercut 206 during rotation, for example, as shown in Figures 9B and 9D.

[0050] In various embodiments, the screw 200 may have a length of, for example, 15 mm, 17.5 mm, 20 mm, 22.5 mm, 25 mm, 27.5 mm, or 30 mm. In certain embodiments, the head 202 of the screw 200 may have a diameter of, for example, 5.0 mm or 6.0 mm.

[0051] Removal screwdriver As described above, a removal driver 400 configured to remove a bone screw 200 seated between vertebral bodies or in a spinal implant 100 is disclosed herein. Figures 6A-6B, 7A-7B, 8, 9A-9E, and 10A-10C show exemplary embodiments of the removal driver 400 disclosed herein.

[0052] In some embodiments, the removal driver 400 includes an outer shaft 401 containing a cavity, lumen, or cannula insertion section 404. The outer sleeve or shaft 401 may include a cannula-shaped engagement mechanism 403 at its tip. For example, in the embodiments shown in Figures 7A-7B, the cannula-shaped engagement mechanism 403 is a hexalobular drive mechanism, but other configurations are also possible, including, for example, a star drive, a hexagonal drive, or the geometric shape of other drivers, as will be understood by those skilled in the art. The engagement mechanism 403 is configured to engage with the corresponding mechanism 203 on the bone screw head 202 (Figure 8), as described above.

[0053] The cannula insertion section 404, which extends axially through the engagement mechanism 403 and the outer shaft 401, is configured so that the tip of the inner shaft 402 can pass through the cannula insertion section 404. The inner shaft 402 may include an elongated body 407 and a threaded tip 410. The threaded tip 410 may be configured to engage with the head 202 of the bone screw 200 or a nearby female thread 204, thereby allowing the bone screw 200 to be unthreaded from the spinal implant 100.

[0054] In some embodiments, the clutch 414 connects the outer shaft 401 to a drive mechanism 403, which may be, for example, a hexalobular driver. Turning clockwise or counterclockwise disengages the clutch 414, and the internal threads of the inner shaft 402 may be configured to pull the removal driver 400 onto the screw head 202. This action is configured to push the flexible latch 108 of the implant 100 out of the way (particularly in Figure 2D). Turning in the opposite direction may be configured to engage and disengage the bone screw 200 from the implant 100. The bone threads 204 are held by the driver 400 during removal.

[0055] Figure 8 shows an exemplary embodiment of a removal driver 400 engaged with a bone screw 200. The inner shaft 402 may be configured to translate at least pteroposteriorly relative to the outer sleeve 401 through the cannula insertion portion 404 of the outer sleeve 401. This pteroposterior translation of the inner shaft 402 relative to the outer shaft 401 may be initiated manually by a user, such as a surgeon, in part by actinguating a clutch 414. In this position, the outer sleeve 401 may be configured to flex a flexible latch 108 of the spinal implant 100 that latches onto the screw head 202 of the bone screw 200.

[0056] In some embodiments, once the inner shaft 402 is securely engaged with the threads 204 of the bone screw head 200, the outer shaft 401 can be translated pteroarticularly relative to the inner shaft 402. In some specific embodiments, the outer sleeve 401 is pushed down against the bone screw head 200 relative to the inner shaft 402, and the inner shaft 402 engages with the bone screw head 202, allowing the latch 108 (Figures 9B, 9D) to be pushed out of the way. At this point, the screw 200 can be unscrewed and removed from the implant 100.

[0057] In some embodiments, the cannula-shaped drive mechanism 403 may be hexalobular in shape. The cannula-shaped drive mechanism 403 may be located at or near the tip of the outer sleeve 401. In some embodiments, the threaded tip 410 of the inner shaft 402 is positioned tip-side relative to the tip of the outer sleeve 401. In other words, in such embodiments, the threaded tip 410 of the inner shaft 402 extends tip-side from there through the outer sleeve 401 and the cannula-shaped drive mechanism 403. In some embodiments, the drive mechanism 403 is configured to connect to the mechanism 203 of the threaded head 202 of the bone screw 200 to facilitate engagement with the bone screw 200. In some embodiments, as shown in Figure 8, the removal driver 400 is configured to unlock the bone screw 200 when the longitudinal axis of the bone screw 200 is aligned with the longitudinal axis of the driver 400. In some embodiments, the removal driver 400 is configured to unlock the bone screw 200 even if the longitudinal axis of the bone screw 200 is tilted or angled away from the longitudinal axis of the driver 400. In some embodiments, the inner shaft 402 further includes a knob 412 located at the base end of the inner shaft 402 (Figure 6A). The knob 412 is thereby rotatable by the user, thereby causing rotation of the inner shaft 402.

[0058] Referring to Figures 10A to 10C, in some embodiments, the removal driver 400 for removing the bone screw 200 from the spinal implant 100 may include a tip portion 409 having a tip portion 411 and a drive mechanism 403 positioned proximal to the tip portion 411. The drive mechanism 403 may be configured to connect to the corresponding mechanism 203 on the head 202 of the bone screw 200 to facilitate engagement with the bone screw 200 in the manner described above. In some embodiments, the tip portion 411 is thinner than the drive mechanism 403 along the lateral or radial direction. In some embodiments, the drive mechanism 403 includes a trilobe 405 (Figure 10A) having three lobes, each lobe being substantially equally separated from the other lobes. In some embodiments, the trilobe 205 on the bone screw 200 is identical in size to a standard hexalobular with every other lobe (a total of three lobes) removed, as can be seen in Figure 10A. In some embodiments, the lobes of the trilobes 405, 205 are arranged at equal intervals from one another along the perimeter, and each lobe has the same size and shape. In some embodiments, the trilobe 405 of the removal driver 400 is sized and shaped so that it can be inserted into the gap between adjacent lobes of the trilobe 205 of the bone screw head 202. In some embodiments, the trilobe 405 of the removal driver 400 is the same size and shape as the trilobe 205 of the bone screw head 200. In some embodiments, the trilobe 405 is configured to rotate and connect to the undercut 206 of the corresponding feature 205 of the head 202 of the bone screw 200.

[0059] In some embodiments, the tip portion 409 of the removal driver 400 further includes a cam surface 408 positioned proximal to the drive mechanisms 403, 405. The cam surface 408 may be configured, when rotated, to flex outward the flexible latch 108 of the implant 100 from its position of latching onto the head 202 of the bone screw 200, thereby moving the flexible latch out of the way of the bone screw.

[0060] Figures 9A to 9E illustrate exemplary embodiments showing a series of operations for removing a bone screw 200 using the bone screw removal driver 400 disclosed herein. Figures 9A and 9B show a simplified form of the spinal implant 100 with only the frame structure and the fully seated bone screw 200 latched by a flexible latch 108. In this particular embodiment, the removal driver 400 is inserted into the head 202 of the bone screw 200. The removal driver 400 is inserted so that the trilobe drive mechanism 405 (Figure 10A) engages with an undercut 206 of the head 202 of the bone screw 200, located on the tip side of the trilobe feature 205 of the head 202 of the bone screw 200, and is then rotated. Subsequently, as the removal driver 400 rotates together with the bone screw 200 in Figures 9C to 9D, the cam surface 408 of the removal driver 400 rotates. Such rotational motion of the cam surface 408 (e.g., without translational motion) pushes the flexible latch 108 and its lip 109 so as not to obstruct the bone screw 200, thereby allowing for continuous loosening of the bone screw 200. This process allows the bone screw 200 to be removed from the spinal implant 100. Figure 9E shows the bone screw 200 loosened and ready to be pulled away from the spinal implant 100.

[0061] In some embodiments, the removal driver 400 advantageously allows for a single-piece (e.g., solid) driver tip portion that can actively hold the bone screw 200 during removal. In some embodiments, the removal driver 400 can be used to unlock locking mechanisms featuring springs, tabs, or flexible mechanisms covering the bone screw 200 in a variety of spinal applications, including but not limited to cervical plates, intermediate fixation cages, and anterior lumbar interbody fusion (ALIF) plates. As will be understood by those skilled in the art, the removal driver 400 disclosed herein can also be used with conventional U-shaped joints applied at an angle.

[0062] driver Referring to Figures 11A to 11D and Figures 12A to 12C, a screwdriver 500 for inserting a bone screw 200 into a spinal implant 100 is disclosed herein.

[0063] In some embodiments, the screwdriver 500 features a flexible tab component 501 permanently attached to the elongated body 506 of the driver 500. The flexible tab 501 elastically flexes outward when a screw 200 is loaded onto the tip, forming an interlocking fit with the bone screw 200. This interlocking fit holds the screw 200 in place during use. In some embodiments, the flexible tab 501 advantageously removes minimal material from the tip portion of the driver, which increases the strength of the screwdriver 500.

[0064] In some embodiments, the screwdriver 500 includes an elongated body 506 having a tip portion 507, a tip portion 504, and a drive mechanism 505 located on the proximal outer surface 508 of the driver 500 relative to the tip portion 504. The drive mechanism 505 may be configured to engage with a corresponding feature 205 of the head 202 of the bone screw 200 to facilitate engagement with the bone screw 200. As shown in Figures 11A-11D and 12A-12C, in some embodiments, the drive mechanism 505 includes a trilobe shape having three lobes 505a separated by three grooves 505b. The lobes 505a and grooves 505b can be evenly distributed around the cross-section of the driver 500. Each of the three grooves 505b may be positioned between two adjacent lobes 505a of the trilobe.

[0065] The screwdriver 500 may further include a flexible tab 501 extending toward the tip portion 504. The flexible tab 501 may include a base portion 509 that is rigidly anchored to the elongated body 506. The base portion 509 of the tab 501 may be thicker than the tip portion of the tab, for example, in the radial direction. The flexible tab 501 may also include a tip portion 510 that is bendable or movable radially inward or outward. The movement of the tip portion 510 may be caused by biasing energy or force. In some embodiments, the flexible tab 501 is configured to bend or move inward from its resting position when a bone screw 200 is loaded into the driver 500. In some embodiments, as can be seen in Figures 11A, 12A, and 12C, the flexible tab 501, in a resting or equilibrium state, seats radially outward relative to the outer surface 508 of the tip portion 504 of the screwdriver 500. After the bone screw 200 is properly loaded into the screwdriver 500, the flexible tab 501 may be configured to bias radially outward to hold the bone screw 200 in the screwdriver 500. In some embodiments, as can be seen in Figure 11D, the flexible tab 501 may be lower than the outer surface 508 of the tip portion 504 of the screwdriver 500, i.e., seated radially inward relative to the outer surface 508, or flush with the outer surface 508. Figure 11D shows a cross-sectional view of the tip portion 504 of the bone screwdriver 500 with the bone screw 200 loaded. In some embodiments, the flexible tab 501 includes metal, alloy, or any other flexible material. In some embodiments, as can be seen in Figures 11A, 11D, and 12A, the flexible tab 501 is at least partially positioned within a groove 505b on the outer surface 508 of the driver 500.

[0066] In certain embodiments, the tip portion 504 may be narrower than the drive mechanism 505, for example, in the radial direction, and / or the circumference of the tip portion 504 may be smaller than the circumference of the rest of the tip portion 504 of the screwdriver 500.

[0067] Instruments for spinal fusion implants As described above, embodiments of the present invention provide an inserter 300 used for inserting an implant 100. Many specific inserter configurations and embodiments are further described herein with general reference to Figures 13-15, 16A-16F, 17A-17C, 18A-18B, 19, and 20.

[0068] Straight inserter First, referring to Figures 13 to 15, an inserter 300 according to one embodiment of the present invention is shown in a straight configuration. As previously mentioned, the inserter 300 may include an outer shaft 301 having an elongated body 302 in which a cavity or lumen is located. An inner shaft 310 may be located within the lumen of the elongated body 302. The inner shaft 310 may include a tip 311 including an engagement mechanism 312 configured to mate and engage with the engagement opening 113a of the implant 100 during use, as described above. A pair of opposing posts 304 may be provided on the tip of the outer shaft 302. The posts 304 may be configured to engage with a corresponding pair of engagement slots 113b on the implant 100 during use.

[0069] The barrel cam element 313 is located at the tip of the inner shaft 310 and may be positioned proximal to the tip 311 and the engagement mechanism 312. The barrel cam element 313 is configured to provide a non-threaded connection to the implant 100. A pair of opposing pins 303 configured to engage with the barrel cam element 313 may extend radially inward from the inner surface of the elongated body 302. The two opposing pins 303 may be located at or near the tip of the barrel cam element 313 when the inserter 300 is in the unlocked position (Figure 16A). The two opposing pins 303 are configured to rotate, for example, about 90° around the inner shaft 310 and translate toward the tip as the inserter 300 moves to the locked position (Figure 16B). Figure 16A shows the barrel cam element 313 in its unlocked configuration, i.e., unlocked from the implant 100, and Figure 16B shows it in its locked configuration, i.e., locked to the implant 100.

[0070] A thumbwheel 320 (Figure 13) can be screw-coupled to the base end of the inner shaft 310. The thumbwheel 320 may be rotated by the user to cause rotation of the barrel cam element 313, thereby simultaneously causing rotation and translation of the inner shaft 310 relative to the outer shaft 302 and the spinal implant 100. This results in rotation and translation of the engagement mechanism 312, as shown in the transitions from Figures 16C to 16D and Figures 16E to 16F. In some embodiments, the rotation of the thumbwheel 320 simultaneously causes rotation and translation of the inner shaft 310 relative to the outer shaft 302, causing engagement or disengagement of the engagement mechanism 312 of the tip 311 and the inner shaft 310 with the engagement opening 113a of the implant 100, thereby locking or unlocking the inserter 300 to or from the spinal implant 100.

[0071] The resulting positions of the engagement mechanism 312 and post 304, based on the position of post 303 within the barrel cam element 313, are shown in Figures 16C to 16F. The engagement mechanism 312 is shown in its unlocked configuration, i.e., unlocked from the implant 100, in Figures 16C and 16E, and in its locked configuration, i.e., locked to the implant 100, in Figures 16A and 16E. The barrel cam element 313 is configured to allow the inserter 100 to lag behind (or be pulled back from) the implant 100 in a manner similar to screw engagement, providing a robust connection to the implant 100. At the same time, the barrel cam element 313 avoids some of the sticking / galling problems commonly seen with threaded attachments to titanium devices.

[0072] In certain embodiments, as shown in Figure 15, the inner shaft 310 may include a multi-part shaft and may be coupled in a manner configured to actuate the inserter 300, i.e., to engage and disengage with the implant 100, via a thumbwheel 320 or a detachable T-handle wrench 330. The detachable T-handle wrench can be removed from its position on the inserter 300, as shown in Figure 17A, and is applied to the base shaft hexagonal connector 331, as shown in Figure 17B, to provide additional torque when used in configurations such as the one shown in Figure 17C.

[0073] Angled inserter Referring next to Figures 18A-18B, 19, and 20, another embodiment of the inserter 300 is shown in an angled configuration. The angled inserter 300 in Figures 18A-18B, 19, and 20 includes components similar to those described above with respect to the linear inserter 300 in Figures 13-14, for example. Similar to the linear inserter, the angled inserter includes a barrel cam element 313 configured to provide a non-screw connection between the inserter 300 and the implant 100.

[0074] In the embodiments shown in Figures 18A and 18B, the insertor 300 includes an outer shaft 301 having an elongated body 302 with a cavity or lumen inside. An inner shaft 310 is positioned within the cavity. The inner shaft 310 includes a flexible coupling 316. The coupling 316 is configured to adjust the angle of the insertor 300 to about 15° with respect to the longitudinal axis of the outer shaft 301 in one of several anatomical planes. In one embodiment, as shown in Figure 19, a lateral-footed insertor is shown, characterized by an angle of about 15° laterally with respect to the longitudinal axis of the outer shaft 301. In another embodiment, as shown in Figure 20, a craniocaudal insertor is shown, characterized by an angle of about 15° craniocaudal with respect to the longitudinal axis of the outer shaft 301. The insertors in Figures 19 and 20 are configured for use in specific implant insertion procedures. For example, a transversely footed insertor, as shown in Figure 19, may be used in anterior lumbar interbody fusion (ALIF) procedures using a transverse incision approach. The transversely footed insertor in Figure 19 may be particularly useful in supine ALIF procedures. Such a method may involve positioning the patient supine, forming a transverse incision, and inserting an implant, such as implant 100, through the incision into the space between target vertebrae, for example, between the lumbar vertebrae, using a transversely footed insertor, such as as shown in Figure 19.

[0075] In another example, the craniocaudal (CC) inserter shown in Figure 20 can be used in ALIF procedures, particularly when the patient has a high sacral inclination or when other difficult anatomical structures are present. The CC inserter in Figure 20 may be particularly useful in ALIF procedures involving the insertion of an implant between the L5 and S1 vertebrae. Such a method may involve positioning the patient in a lateral decubitus position, forming a lateral or oblique incision, and inserting an implant, such as implant 100, through the incision into the space between the target vertebrae, for example, the L5 and S1 vertebrae, using an angled inserter, such as the one shown in Figure 20.

[0076] In some embodiments, the head of the inserter 300, i.e., the tip portion of the inserter 300's joint 316, is made sufficiently thin so that a driver, such as a removal driver 400 or a screwdriver 500, can access and engage the screw that is inserted into or removed from the fixing opening 107 of the implant 100, while the inserter 300 engages and connects to the implant 100 via the engagement mechanism 312 and post 304. This provides further stability during insertion and removal procedures.

[0077] Slap mallet Next, with reference to Figures 21-26, the slap mallet 600 will be described herein. The slap mallet 600 is configured to provide the user with the ability to strike a mallet and reverse the mallet (slap hammer) with a single tool. Conventionally, when a surgeon places or removes an implant, such as implant 100, they use a separate mallet and slap hammer to strike other instruments. Using multiple tools requires an additional path between the surgeon and the operating room technician. The slap mallet 600 provides a single device that the surgeon can operate independently and is configured to provide three different impact modes for insertion into and withdrawal from an incision. For example, the first impact mode may be useful for insertion, where the force is transmitted through the mallet head 607 and / or other smooth surface. Another mode can apply a force that helps to remove through an incision. These forces may be applied through a U-shaped channel 608 within the mallet head 607 that extends from the tip towards the proximal end of the mallet head 607. Channel 608 may be configured to allow the user to apply an axial force outward relative to the incision by striking the instrument with a backmallet (striking in the reverse direction). Alternatively, the removal force may be applied by a recessed planar feature 609 of the mallet head 607. The recessed planar feature 609 may be configured to engage with a complementary size and shape feature on another instrument, such as an inserter. A third force can be applied axially or linearly using a slap mallet 600.

[0078] In one embodiment, the slap mallet 600 includes a first shaft 601 and a second shaft 602 at least partially positioned within the first shaft 601. The first shaft 601 may be configured to be used as a handle, while the second inner shaft 602 may be configured to function as an extension rod. The slap mallet 600 may further include a button 603, a biasing element 604, a pin 605, and a clutch assembly 606. In one embodiment, the slap mallet 600 includes a mallet head 607 that can be coupled to the first shaft 601, with the second shaft 602 at least partially positioned within the first shaft 601. The first shaft 601 may be configured to be used as a handle, while the second shaft 602 may be configured to be used as an extension rod.

[0079] The slap mallet 600 can be used like a standard slap hammer with the second rod 602 substantially or completely positioned within the first shaft 601, as shown, for example, in Figure 21. In this position, when the slap mallet 600 is used as a mallet, the second shaft 602 can retract into the first shaft 601 and be held in that position by a biasing element 604. The biasing element 604 may be, for example, a spring, a screw, or other means for holding the position of the second shaft 602.

[0080] To use the slap mallet 600 as a slap hammer, the second shaft 602 can be extended in the proximal direction, and the slap mallet 600 can be attached to the tool in a manner easily understood by those skilled in the art. For quick engagement and disengagement with the tool, a quick attachment can be performed between the second shaft 602 and the tool. Alternatively, the second shaft 602 can also be screwed into the tool. By keying the second shaft 602 to the first shaft 601 of the mallet, the second shaft 602 can be screwed into the tool each time the first shaft 601 rotates. In certain embodiments, the T-handle 330 shown in Figures 17A-17C can be further coupled to the proximal end of the inner shaft 602 relative to the inserter 300 (Figure 26). During use, the T-handle 330 allows the user to apply force in different ways, including in different directions.

[0081] Trial inserter Next, referring to Figures 27 to 34, a trial inserter 700 according to an embodiment of the present invention is provided. The trial inserter 700 may include a tip component 701 which is threaded and configured to connect directly to an implant such as an implant 100 or a trial.

[0082] The trial inserter 700 may include a shaft having a plurality of connected parts, the end part 701 of which may be the terminal and tip part. The end part 701 may be considered a first link in the connected shaft and may be coupled at its base end to a second link 702. The rounded tip of the second link 702 is received into the base end of the end part 701 and coupled in place by a coupler 704 that passes through the tip opening 703 of the second link 702. The coupler 704 may be, for example, a pin. The second link 702 may further include a rounded base end that is received into the tip of the barrel link 705 in a manner similar to a ball socket joint, providing rotational flexibility between the second link 702 and the barrel link 705. When the base end of the second link 702 is positioned into the tip of the barrel link 705, an opening 706 is formed that passes through the joint between the two components 702, 705. The opening 703 can be rotated, for example, about 90° relative to the opening 706.

[0083] Returning to the opening 706, the coupler 704 passes through the opening 706, thereby coupling the components together. The opening 706 may have an hourglass shape such that the diameter of the opening 706 at its center is smaller than the diameter at its opening ends, allowing the axis of the coupler 704 to have less rotational movement than at its ends. This configuration of the coupler 704 within the opening 706 is configured to allow a range of motion of about 10° from the axis of the coupler 704.

[0084] The barrel link 705 is configured to provide translation of the entire tip link mechanism, including the tip component 701, the second link 702, and the barrel link 705, relative to the shaft 707. The barrel link 705 is connected to the main shaft 707 via a keyed drive mechanism 708 and a coupler 704, thereby enabling translation and torque transmission. The keyed drive mechanism 708 may be, for example, a square drive. The coupler 704, located at the base and tip of the barrel link 705, may be substantially parallel to each other. A biasing element 709, such as a coil spring, may be placed between the barrel link 705 and the shaft 707. The biasing element 709 is configured to push the link mechanisms 701, 702, and 705 toward the tip to assist in the connection. Thus, the tip component link 701 is pinned to the second link 702, the second link 702 is pinned to the barrel link 705, the barrel link 705 is pinned to the main shaft 707, and the plunger spring 709 is captured between the barrel link 705 and the shaft 707.

[0085] In another embodiment, as shown in Figures 31-32, the tip component 701 is directly coupled to the shaft 707 at its base end without the interposition of the second link 702 and the barrel link 705. In this embodiment, the tip component 701 is configured to be biased toward the tip by a spring 709.

[0086] The aforementioned components shown in Figures 27 to 34 are housed within an outer shaft 710, which may be formed from first and second outer shaft portions 710a and 710b (Figure 27). The tip component 701 is configured to translate inward and outward from the shaft or housing 710. As described herein with respect to Figures 33 to 34, for example, when the spring-loaded and connected inner shaft, including 701, 702, and 705, is biased outward toward the tip, the threads located at the tip of the tip component 701 are configured to readily engage with the implant. The connected inner shaft configuration described herein further provides an improved ability to disassemble the device, which can be particularly advantageous for cleaning and sterilization purposes. Similarly, in the embodiments of Figures 31 to 32, the biasing action of the spring 709 on the tip component 701 positions the threads located at the tip of the tip component 701 in a position to readily engage with the implant.

[0087] In another embodiment of the trial inserter, the tip component is threaded for direct coupling to the implant or trial. This tip component link (first link) is rotated to engage via an internal link mechanism, forming a connection. This tip link is connected to the main shaft via a square drive mechanism and a slotted pin, enabling translation and torque transmission. A spring between the tip link and the main inner shaft pushes the link mechanism toward the tip, assisting the connection. All of these are housed within the outer shaft. The tip link is pinned to the main shaft, capturing a plunger spring between these two components. The tip link can move in and out of the outer shaft or housing.

[0088] Unless otherwise specified, all technical terms used herein have the same meaning as those generally understood by those skilled in the art in which the present invention pertains. Where used herein and in the appended claims, the singular forms “a, an” and “the” include plural references unless the context clearly indicates otherwise. References to “or” herein include “and / or” unless otherwise specified. As used herein and in the claims, unless otherwise specified, the terms “about,” “approximately,” “abstract,” and “substantially” refer to variations of + / -1%, + / -2%, + / -3%, + / -4%, + / -5%, + / -6%, + / -7%, + / -8%, + / -9%, + / -10%, + / -11%, + / -12%, + / -14%, + / -15%, + / -16%, + / -17%, + / -18%, + / -19%, or + / -20% or less, depending on the embodiment. As a further non-limiting example, about 100 millimeters refers to a range of 95 millimeters to 105 millimeters, 90 millimeters to 110 millimeters, or 85 millimeters to 115 millimeters, depending on the embodiment.

[0089] Preferred embodiments of the present invention have been shown and described herein, but it will be apparent to those skilled in the art that such embodiments are provided merely as examples. Those skilled in the art will be able to conceive of numerous variations, modifications, and substitutions without departing from the present invention. It should be understood that various alternatives to the embodiments of the present invention described herein may be used when carrying out the present invention. The following claims define the scope of the present invention, and the methods and structures within these claims, and their equivalents, are intended to be covered thereby.

Claims

1. A spinal implant, said spinal implant is Upper end plate and Lower end plate and A central body fixedly positioned between the upper end plate and the lower end plate, comprising a central body defining a first end, a second end opposite to the first end, and at least two sides, A plurality of fixed openings, each opening partially defined by a solid wall, including, The spinal implant defines a fusion opening between the upper endplate and the lower endplate, Each of the plurality of fixed openings extends from the second end of the central body to either the upper end plate or the lower end plate, At least one of the solid walls is A retaining mechanism configured to hold a bone screw in one or more of the aforementioned multiple fixing openings, Includes a confirmation mechanism configured to provide tactile feedback to the user when the bone screw is fully inserted into the corresponding fixing opening, The confirmation mechanism includes a screw thread integrally formed as part of the solid wall, thereby providing tactile feedback to the user through contact between the screw thread and the raised portion of the bone screw. Spinal implants.

2. The retaining mechanism includes a flexible latch having a lip at its base end, The spinal implant according to claim 1, wherein the flexible latch is configured to allow a bone screw to pass through the corresponding fixing opening in a first direction, and to hold the bone screw in the corresponding fixing opening after the proximal portion of the bone screw has passed through the lip.

3. The spinal implant according to claim 1, wherein the screw thread is a three-start thread.

4. The spinal implant according to claim 1, wherein the screw thread is located at the tip of the corresponding fixing opening.

5. An insertion tool engagement mechanism that does not come into contact with the solid wall of the plurality of fixed openings, An insertion tool engagement mechanism that contacts at least one of the solid walls defining the fixed opening, or The spinal implant according to claim 1, further comprising an insertion tool engagement mechanism located between at least two solid walls defining a fixed opening and in contact with these solid walls.

6. The first fixing opening of one or more of the aforementioned fixing openings extends from the second end to the upper end plate. The first lip of the first flexible latch of the first fixed opening extends at least toward the upper end plate, The second fixing opening of one or more of the aforementioned fixing openings extends from the second end to the lower end plate. The second lip of the second flexible latch of the second fixed opening extends at least toward the lower end plate, and The spinal implant according to claim 1, wherein the first flexible latch or the second flexible latch is integrated with the solid wall or the central body, or is fixedly attached to the solid wall or the central body.

7. The solid walls defining each of the plurality of fixed openings are not in contact with each other. At least one of the solid walls defining a fixed opening is in contact with at least one other solid wall defining a different fixed opening, or The spinal implant according to claim 1, wherein at least one solid wall defining a fixed opening is in contact with at least one support column of the central body.

8. The spinal implant according to claim 1, wherein the spinal implant is made of titanium.

9. The upper end plate defines a first plurality of pores having a first average pore diameter, The lower end plate defines a second plurality of pores having a second average pore diameter, The central body defines a third plurality of pores having a third average pore diameter, The spinal implant according to claim 1, wherein the third average pore diameter is larger than the first average pore diameter and the second average pore diameter.

10. The first of the plurality of fixed openings extends in a first direction inclined by a first acute angle from the lower end plate, and The spinal implant according to claim 1, wherein the second fixing opening among the plurality of fixing openings extends in a second direction inclined by a second acute angle from the lower end plate.

11. The spinal implant according to claim 1, wherein the first end includes a first height shorter than the second height of the second end.

12. A system, and said system is Bone screws and, Spinal implants, including, The spinal implant is Upper end plate and Lower end plate and A central body fixedly positioned between the upper end plate and the lower end plate, comprising a central body defining a first end, a second end opposite to the first end, and at least two sides, A fixed opening, partially defined by a wall, extending from the second end of the central body to the upper end plate or the lower end plate, The aforementioned wall is A retaining mechanism configured to hold the bone screw within the fixing opening, The system includes a confirmation mechanism configured to provide tactile feedback to the user when the bone screw is fully inserted into the fixing opening, The confirmation mechanism includes a screw thread integrally formed as part of the solid wall, thereby providing tactile feedback to the user through contact between the screw thread and the raised portion of the bone screw. system.

13. The system according to claim 12, wherein the bone screw extends through the fixing opening and beyond the upper end plate or the lower end plate.

14. The retaining mechanism includes a flexible latch having a lip at its base end, The bone screw is held in place within the fixing opening by the flexible latch, The bone screw is positioned beyond the lip into the fixing opening. The system according to claim 13, wherein the lip contacts and holds the head of the bone screw, thereby preventing the bone screw from coming out of the fixing opening.

15. The confirmation mechanism includes a screw thread integrally formed as part of the wall, The bone screw has a base portion and a raised portion of the base portion, The system according to claim 13, wherein the raised portion and the screw threads are in contact.

16. A system, and said system is Including spinal implants, The spinal implant is Upper end plate and Lower end plate and A fusion opening is defined between the upper end plate and the lower end plate, A central body fixedly positioned between the upper end plate and the lower end plate, comprising a central body defining a first end, a second end opposite to the first end, and at least two sides, A first fixed opening, partially defined by a first wall and extending from the second end of the central body to the upper end plate, wherein the first wall includes a first holding mechanism and a first confirmation mechanism, A second fixing opening, partially defined by a second wall extending from the second end of the central body to the upper end plate, wherein the second wall includes a first holding mechanism and a second confirmation mechanism, A third fixing opening, partially defined by a third wall extending from the second end of the central body to the lower end plate, wherein the third wall includes a third holding mechanism and a third confirmation mechanism, A fourth fixed opening, partially defined by a fourth wall extending from the second end of the central body to the lower end plate, wherein the fourth wall includes a first retaining mechanism and a fourth confirmation mechanism, The confirmation mechanism includes a screw thread integrally formed as part of the solid wall, thereby providing tactile feedback to the user through contact between the screw thread and the raised portion of the bone screw. system.

17. A first bone screw extending through the first fixing opening and beyond the upper end plate, A second bone screw extending through the second fixing opening and beyond the upper end plate, A third bone screw extending through the third fixing opening and beyond the lower end plate, The system according to claim 16, further comprising a fourth bone screw extending through the fourth fixing opening and beyond the lower end plate.

18. The first retaining mechanism includes a first flexible latch that is flexed by the first head of the first bone screw and contacts the first head, The second retaining mechanism includes a second flexible latch that is flexed by the second head of the second bone screw and contacts the second head. The third retaining mechanism includes a third flexible latch that is flexed by the third head of the third bone screw and contacts the third head, and The system according to claim 17, wherein the fourth retaining mechanism includes a fourth flexible latch that is flexed by the fourth head of the fourth bone screw and contacts the fourth head.

19. The first confirmation mechanism includes a first screw thread integrally formed as part of the first wall, The second confirmation mechanism includes a second screw thread integrally formed as part of the second wall, The third confirmation mechanism includes a third screw thread integrally formed as part of the third wall, The fourth confirmation mechanism includes a fourth screw thread integrally formed as part of the fourth wall, The first bone screw has a first protrusion at its first proximal end portion, The second bone screw has a second protrusion at its fourth proximal end portion. The third bone screw has a third protrusion at its fourth proximal end portion. The fourth bone screw has a fourth protrusion at its fourth proximal end, The first raised portion is in contact with the first screw thread, The second raised portion is in contact with the second screw thread, The third protrusion is in contact with the third screw thread, and The system according to claim 16, wherein the fourth protrusion is in contact with the fourth screw thread.

20. An inserter for inserting a spinal implant as described in Claim 1, wherein the inserter is An outer shaft comprising an elongated body containing a cavity inside, and two opposing pins near the tip of the elongated body, wherein the two opposing pins extend inward from the inner surface of the elongated body, An inner shaft configured to be received within the cavity of the outer shaft, the inner shaft comprising a tip receivable into the engagement opening of the spinal implant and a barrel cam element near the tip, the barrel cam element configured to engage with the two opposing pins of the outer shaft, A thumbwheel screw-connected to the base end of the inner shaft, the thumbwheel is configured to rotate to cause rotation of the barrel cam element, thereby simultaneously rotating and translating the inner shaft relative to the outer shaft and the spinal implant, Insertor.

21. The inserter according to claim 20, wherein the simultaneous rotation and translation of the inner shaft causes the tip to engage with the engagement opening, thereby locking or unlocking the inserter to the spinal implant.

22. The inserter according to claim 20, wherein the outer shaft further includes two posts at the tip of the elongated body, each of the two posts configured to engage with a lateral engagement slot of the spinal implant.

23. The inserter according to claim 20, wherein the two opposing pins are located at or near the tip of the barrel cam element in the unlocked position.

24. The inserter according to claim 20, wherein the two opposing pins are located at or near the base end of the barrel cam element in the locked position.

25. A driver for removing a bone screw from a spinal implant according to Claim 1, wherein the driver is The outer sleeve includes an internal cavity, The internal shaft includes a threaded tip, the threaded tip being configured to connect with the threaded head of a bone screw, thereby loosening the bone screw from the spinal implant. The inner shaft is translatable at least toward the tip of the outer sleeve through the cavity of the outer sleeve, and the outer sleeve is configured to flex a flexible latch that latches onto the threaded head of the bone screw. driver.

26. The driver according to claim 25, wherein the outer sleeve includes a cannula-shaped hexalobe driving mechanism at or near the tip of the outer sleeve.

27. The screwdriver according to claim 26, wherein the threaded tip of the inner shaft is located on the tip side relative to the tip of the outer sleeve.

28. The driver according to claim 26, wherein the hexalobular drive mechanism is configured to be coupled to a corresponding feature of the threaded head of the bone screw in order to facilitate engagement with the bone screw.

29. The driver according to claim 25, configured to release the lock of the bone screw when the longitudinal axis of the bone screw is aligned with the longitudinal axis of the driver.

30. The driver according to claim 25, configured to release the lock of the bone screw when the longitudinal axis of the bone screw is tilted away from the longitudinal axis of the driver.

31. The driver according to claim 25, wherein the inner shaft further includes a knob at its base end, the knob being rotatable by the user, thereby rotating the inner shaft.

32. A driver for removing a bone screw from a spinal implant according to Claim 1, wherein the driver is A tip portion having a tip, A drive mechanism located on the proximal end side with respect to the tip, configured to be coupled to a corresponding feature of the head of the bone screw in order to facilitate engagement with the bone screw, The drive mechanism includes a cam surface located on the proximal end side, which is configured to bend outward a flexible latch that latches onto the head of the bone screw, thereby moving the flexible latch so as not to interfere with the bone screw. driver.

33. The driver according to claim 32, wherein the tip is thinner than the drive mechanism.

34. The driver according to claim 32, wherein the drive mechanism includes a trilobe.

35. The driver according to claim 32, wherein the trilobe is configured to rotate and engage with an undercut of the corresponding feature of the head of the bone screw.

36. The driver according to claim 32, further comprising an engagement mechanism configured to attach the tip portion to the handle.

37. The driver according to claim 32, wherein the cam surface is located at least in the circumferential direction on the outer surface of the tip portion.

38. A driver for inserting a bone screw into a spinal implant according to Claim 1, wherein the driver is A long, slender body with a tip, The tip and, A drive mechanism located on the outer surface of the driver on the proximal end side relative to the tip, the drive mechanism configured to be coupled to a corresponding feature of the head of the bone screw in order to facilitate engagement with the bone screw, A flexible tab extending toward the tip, configured to bias outward to hold the bone screw in the driver when the bone screw is loaded into the driver for insertion, is included. driver.

39. The driver according to claim 38, wherein the flexible tab comprises a metal or alloy.

40. The driver according to claim 38, wherein the flexible tab is at least partially positioned within a groove on the outer surface of the driver.

41. The driver according to claim 38, wherein the drive mechanism includes corresponding trilobe features evenly distributed around the tip portion.

42. The driver according to claim 41, wherein the drive mechanism includes three grooves for separating adjacent lobes of the trilobe mechanism.

43. The driver according to claim 42, wherein the flexible tab is at least partially positioned in one of the three grooves.

44. The driver according to claim 38, wherein the flexible tab is configured to move inward when the bone screw is loaded into the driver.

45. The driver according to claim 38, wherein the flexible tab, in a stationary state, is seated radially outward from the outer surface of the driver.

46. The driver according to claim 38, wherein the flexible tab includes a base portion that is thicker than its tip portion.

47. The driver according to claim 38, wherein at least a portion of the flexible tab is firmly anchored to the elongated body of the driver.

48. The driver according to claim 38, wherein the tip is thinner than the drive mechanism.

49. The driver according to claim 38, wherein the corresponding feature of the head of the bone screw includes a trilobe feature.

50. The driver according to claim 49, wherein the trilobe feature is compatible with a driver having a hexalobular drive feature.

Images