JP6100982B1 - Inserter for expandable spinal interbody fusion device - Google Patents

Abstract

The elongate inserter has a distal end releasably connected to an expandable interbody fusion device and a proximal end that includes a trigger actuator. The interbody fusion device comprises an upper endplate and a lower endplate that are movable in an expanding direction relative to each other within the intervertebral disc space. The inserter engages and cooperates with the complementary surface of the expansion structure in the device after operation of the trigger actuator and includes a ramp surface that causes the upper and lower endplates to move away from each other Provide a platform. The drive is supported by the inserter to push the insert between the upper and lower endplates after expansion of the device.

Description

  The present invention relates generally to the field of spinal implants, and more particularly to an inserter for an expandable spinal interbody fusion device to expand an expandable device within the spine. is there.

  Spinal implants, such as spinal interbody fusion devices, are used to treat degenerative disc disease and other injuries or defects in the spinal disc between adjacent vertebrae. The intervertebral disc may be hernia or suffer from various degenerative conditions, thereby impairing the anatomical function of the spinal disc. The most prevalent surgical treatment for these conditions is to fuse the two vertebrae surrounding the affected disc. In most cases, the entire disc except for a portion of the annulus is removed by a discectomy. A spinal fixation device is then introduced into the intervertebral disc space, and a suitable bone graft or substitute aggregate is placed substantially in and / or adjacent to the device, and fixation between two adjacent vertebrae. Promote.

  Some spinal devices for achieving fixation are also expandable to compensate for the disc height between adjacent vertebrae. Examples of expandable interbody fusion devices are disclosed in US Pat. Nos. 6,028,028, issued on Jul. 22, 2003, and 2,028,2011, and issued on Jun. 28, 2011. Patent Document 3 described above. Patent Document 1, Patent Document 2, and Patent Document 3 each introduce a series of elongated inserts called wafers sequentially in a percutaneous approach, and gradually introduce the vertebral body parts facing each other. Are disclosed to stabilize the spine and correct the height of the spine, and the wafer has the feature that the adjacent wafers can be interlocked with multiple degrees of freedom. Patent Literature 1, Patent Literature 2, and Patent Literature 3 are assigned to the same assignee as the present invention, and the disclosures of these patents are incorporated herein by reference in their entirety.

  The problem that arises with such interbody fusion devices that progressively expand such devices using inserts or wafers is that when full expansion is achieved as a result of ligament taxis, additional inserts Is to determine if it cannot be inserted. Thus, it is desirable for the surgeon to know when a sufficient number of inserts have been introduced and whether additional inserts can be introduced to stabilize the spine and correct the spine height. One approach to solving this problem is described in commonly assigned US Pat. No. 6,037,028, issued September 9, 2014, which is incorporated herein by reference.

  Therefore, there is a need for an improved expandable interbody fusion device and an inserter for expanding and inserting such a device, which is when proper expansion of the device is achieved and additional inserts are introduced Includes the ability to determine what can be done.

US Pat. No. 6,595,998 US Pat. No. 7,931,688 US Pat. No. 7,967,867 U.S. Pat. No. 8,828,019 U.S. Patent Application No. 13 / 795,054

  It is an object of the present invention to provide an inserter for dilating an expandable interbody fusion device and sequentially inserting one or more inserts as the device expands. A further object is to realize an inserter function that allows the surgeon to determine that a suitable expansion has been reached and that no additional inserts can be inserted.

FIG. 6 is a top perspective view of an apparatus comprising an inserter releasably attached to an expandable spinal interbody fusion device according to an embodiment of the present invention with the expandable interbody fusion device unexpanded. is there. 1b is a side view of the apparatus of FIG. 1b is a top view of the apparatus of FIG. FIG. 1c is an enlarged view of the distal portion of the device as circled in FIG. 1c. FIG. 1b is a top perspective view of the unexpanded fixation device of FIG. 1a. FIG. 4 is a top perspective view of the fixation device of FIG. 3 after being expanded. 3b is an exploded top perspective view of the expanded device of FIG. 3b. FIG. FIG. 3b is a side view of the expanded device of FIG. 3b. Fig. 5b is a cross-sectional view of the device of Fig. 5a when viewed along line BB of Fig. 5a. 5b is a cross-sectional view of the device of FIG. 5a when viewed along line CC in FIG. 5a. 3b is a top perspective view of an insert used in the expandable spinal interbody fusion device of FIG. 3a. FIG. 6b is a top view of the insert of FIG. 6a. FIG. FIG. 6b is a longitudinal cross-sectional view of the insert when viewed along line VI-VI in FIG. 6b. FIG. 6b is a bottom view of the insert of FIG. 6a. FIG. 6b is a distal end view of the insert of FIG. 6a. FIG. 3b is a top perspective view of an elevator used in the expandable spinal interbody fusion device of FIG. 3a. FIG. 7b is a top view of the elevator of FIG. 7a. FIG. 7b is a longitudinal cross-sectional view of the elevator when viewed along line VII-VII in FIG. 7b. FIG. 7b is a bottom view of the elevator of FIG. 7a. FIG. 7b is a distal end view of the elevator of FIG. 7a. FIG. 1b is an exploded top perspective view of the track and components of the inserter of FIG. 1a including a translatable lifting platform and a translatable drive. FIG. 9 is an enlarged view of the distal portion of the inserter track and components as circled in FIG. 1c is a cross-sectional view of the inserter and device of FIG. 1a when viewed along line IX-IX of FIG. 1c. FIG. 10 is an enlarged view of a portion A surrounded by a circle in FIG. 9. FIG. 10 is an enlarged view of a portion B surrounded by a circle in FIG. 9. FIG. 3 is a cross-sectional view of the inserter and the distal end of the device when viewed along line AA of FIG. 2 with the expandable device unexpanded. FIG. 3 is a cross-sectional view of the inserter and the distal end of the device when viewed along line BB of FIG. 2 with the expandable device unexpanded. FIG. 11 is a top partial perspective view of the lifting platform and the distal end of the elevator of the expandable device in the position shown in FIGS. 10a and 10b. It is sectional drawing of a raising / lowering platform and an elevator when it sees along line | wire XII-XII of FIG. FIG. 10b is a view similar to FIG. 10a with the elevator platform moved distally to a position to lift the elevator and expand the expandable device, with the first insert partially within the expanded device. . FIG. 10b is a view similar to FIG. 10b with the elevator platform moved distally to a position to lift the elevator and expand the expandable device, with the first insert partially contained within the expanded device. . FIG. 10b is a view similar to FIG. 10a showing a first insert being inserted into an expanded expandable device. In FIG. 13a, the elevator and first insert are lifted and the lifting platform is moved distally to a position that further expands the expandable device, and the second insert is partially contained within the expanded device. It is a similar figure. In FIG. 13b, the elevator and first insert are lifted and the lifting platform is moved distally to a position to further expand the expandable device, and the second insert is partially contained within the expanded device. It is a similar figure. Expanded as shown in the view of FIG. 15a where the second insert has been moved further distally to a position where the elevator is moved away from the first insert to form a space for insertion of the second insert. FIG. 4 is a diagram of an expanded device that has been expanded. Expanded as shown in the view of FIG. 15b where the elevator is moved further distally to a position that moves the elevator away from the first insert to form a space for insertion of the second insert. FIG. 4 is a diagram of an expanded device that has been expanded. FIG. 15 is a view similar to the view of FIG. 14 showing a first insert and a second insert being inserted into an expanded expandable device. It is sectional drawing when it sees along line XVIII-XVIII of FIG. FIG. 10 is a proximal perspective view of an expanded interbody fusion device with a guide pin releasably connected after the insert is removed from the guide pin, with the insert not shown for clarity. FIG. 10 is a top perspective view of an apparatus comprising an inserter releasably attached to an expandable interbody fusion device according to a further embodiment of the invention, wherein the inserter is modular.

  For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and described in the specification that follows. It is understood that no limitation to the scope of the invention is thereby intended. It is further understood that the present invention includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the present invention as would normally occur to one skilled in the art to which the invention pertains. The

  Referring now to FIGS. 1a-1c, 2, 3a-3b, and 4, an apparatus 1 for use in spinal interbody fusion is illustrated. The apparatus 1 includes an expandable interbody fusion device 10 and an inserter 100. The inserter 100 inserts the device 10 into the intervertebral disc space between opposing vertebral bodies of the spine to expand the device in situ and to insert the insert into the expanded device 100. It is an instrument used for The expandable interbody fusion device 10 includes a first element, such as an upper endplate 12, a second element, such as a lower endplate 14, at least one insert 16, and as described in detail below. An expansion structure including the elevator 18 is provided. The height H between the upper endplate 12 and the lower endplate 14 in the unexpanded state as illustrated in FIG. 1b is less than the normal anatomical height of a typical intervertebral disc space. In the present invention, the interbody fusion device 10 is expanded by the inserter 100 from an unexpanded state as shown in FIG. 3a to an expanded height as shown in FIG. Restore the normal anatomical height of the intervertebral disc space, and then insert one or more inserts, such as insert 16, as described, with the expanded upper endplate 12 and lower It is contemplated to form a stack of inserts 16 with the end plate 14. In the particular arrangement described, the fixation device 10 is configured and sized to be implanted into the spine from the posterior approach. In the unexpanded state shown in FIG. 3a, device 10 has a length of about 25 mm, a width of about 10 mm, and an unexpanded height H of about 7 mm. The fixation device 10 may also be configured and sized to be implanted into the spine using a posterior-lateral, anterior or lateral approach, as described.

  The upper end plate 12 as shown in FIGS. 3 a-3 b and 18 is elongated and has a pair of side surfaces 22 and 24 extending longitudinally on each side of the hub 20 and a proximal rear of the upper end plate 12. A hub 20 having a pair of end faces 26 and 28 extending at the end and distal front end, respectively, is provided. The hub 20 is sized and configured to fit within the cavity 48 of the lower endplate 14 and move in a telescopic manner, as will be described. The lower surface 30 of the hub 20 (FIG. 18) is generally flat and planar. A suitable friction or crush rib may be provided between the hub 20 and the cavity 48 of the lower endplate 14 of the inner surface 44a, and when the device 10 is introduced into the intervertebral disc space to be detached. End plate 12 and lower end plate 14 are temporarily held together in the direction of expansion.

  With continued reference to FIGS. 3 a-3 b and FIG. 18, the upper end plate 12 includes a graft chamber defined by an opening 38 that extends through the upper outer surface 12 a and the lower surface 30. According to one arrangement, the upper end plate 12 is formed from a biocompatible polymer such as polyethyl ethyl ketone (PEEK). PEEK is used in healing applications to combine strength, biocompatibility, and elasticity similar to human bones. Other compositions may include derivatives of PEEK, such as carbon fiber reinforced PEEK and PEKK, respectively. In certain embodiments, the upper end plate 12 may further comprise an upper end cap that defines the outer surface 12a. The end cap may be a separate plate formed from a material for promoting bone growth, such as titanium, and may be attached to the endplate 12 by any suitable conventional technique. Alternatively, the top surface 12a can be defined by the coding of a suitable layer of bone growth promoting material, such as titanium, which can be applied by conventional techniques.

  The lower endplate 14 of the interbody fusion device 10 as shown in FIGS. 3a-3b and FIG. 18 is elongate and extends along the longitudinal direction and faces upwardly from the lower outer surface 14a. And a pair of side walls 40 and 42 spaced apart. A pair of spaced apart end walls 44 and 46 extend laterally across the device 10 and project upwardly from the outer surface 14a. The rear end wall 44 is disposed at the rear or proximal end of the device 10 and the front end wall 46 is disposed at the front or distal end of the device 10. Side walls 40, 42, together with rear end wall 44 and front end wall 46, form an internal cavity 48 having an open, full boundary that is open as shown in FIGS. 3 a and 4. The internal cavity 48 fits relatively tightly between the side walls 40 and 42 and the end walls 44 and 46 of the lower endplate 14 in an unexpanded state as shown in FIGS. 1a-1b. Is sized and configured to receive an upper endplate 12 including a central hub 20. The hub 20 of the upper end plate 12 and even the entire stack of inserts 16 were completely contained within the lower end plate 14 during the telescopic expansion of the device 10 as shown in FIGS. And contributes to the torsional strength of the expanded device 10.

  The lower plate 14 as shown in FIGS. 4 and 19 includes a lower inner support surface 54 that supports the elevator 18. The inner surface 54 defines the bottom surface of the cavity 48. The lower endplate 14 further defines an insert passage 50 that passes through the rear end wall 44 in communication with the internal cavity 48 and has a complete boundary through which the one or more inserts 16 are introduced. . The height of the passage 50 as measured perpendicularly from the inner surface 54 is slightly greater than the combined thickness of the insert 16 and the elevator 18. As will be described, only one insert 16 may be introduced at a time with the insert 16 slidably received through the passage 50 on the elevator 18. When the device 10 is expanded and further inserts 16 are introduced sequentially, all inserts 16 placed on the bottom insert 16 placed on the elevator 18 are Retreating out of the device 10 is prevented by the inner surface 44a of the wall 44 (FIG. 4). The rear end wall 44 is threaded to releasably receive a guide pin 108 for use in introducing the insert 16 and delivering bone graft material into the device 10, as will also be described. A connection opening 56 (FIG. 10a) is further defined. The rear end wall 44 additionally provides sidewalls 40 and 42 for use in establishing a rigid connection to the device 10 and releasably attaching the inserter 100 into the device 10 for insertion into the intervertebral disc space. A pair of opposite side openings, such as holes 58, may also be provided.

  The elevator 18 is dimensioned so that the lateral width of the elevator 18 fits and slides relatively closely between the opposing inner surfaces 40a and 42a of the side walls 40 and 42, as shown in FIGS. 5c and 18. Is supported by the inner surface 54 of the lower end plate 14. As such, the lateral movement of the elevator 18 in a direction transverse to the direction of expansion is substantially constrained. In addition, the lower end plate 14 includes a rail 14b that protrudes inwardly from the inner surfaces 40a and 42a and upwards from the lower inner surface 54 toward the upper end plate 12. The upward protrusion of each rail 14b from the inner surface 54 slightly exceeds twice the thickness of the elevator 18. The rail 14b protrudes slidably into a recess 310 that extends into the base 305 of the elevator 18 on each side. The rail 14b substantially constrains the movement of the elevator 18 in the axial direction, while the clearance in the recess 310 is the direction of expansion along the rail 14b as indicated by the arrow 130 in FIG. 10a. Allows the elevator 18 to move freely. As such, the elevator 18 is captured and supported within the lower endplate 14 and is independent along the direction of expansion toward and away from each of the upper endplate 12 and the lower endplate 14. And can be moved.

  In particular, as shown in FIGS. 4, 5 a-5 b, and 18, the lower endplate 14 is defined by an opening 60 that extends through the lower outer surface 14 a and the lower inner surface 54 that communicate with the cavity 48. A graft chamber. According to one arrangement, the lower end plate 14 is formed from a material different from the material of the upper end plate 12. In this embodiment, the lower endplate 14 may be formed from a biocompatible metal such as titanium because of its strength characteristics. Titanium is selected in terms of strength, biocompatibility, processing ability, and X-ray fluoroscopic characteristics (X-ray transmission). Other alternative materials include biocompatible ceramics such as cobalt chrome, stainless steel (both stronger than titanium, but much less X-ray transparent), or silicon nitride or zirconia with X-ray transmission. Including. Titanium and silicon nitride are superior to bone addition and have been demonstrated to be superior to PEEK. In this regard, when the lower endplate 14 is formed from titanium, the lower outer surface 14a provides for accelerated bone growth. However, the lower outer surface 14a may be coded with a suitable layer of bone growth promoting material such as titanium and deposited in a conventional manner to match the roughness / porosity of the upper endplate outer surface 12a.

  If the lower endplate 14 is made of titanium or other suitable metal with X-ray transparency, the window 62 allows visual observation of bone penetration growth by suitable imaging techniques such as fluoroscopy. As shown in FIGS. 3 a to 3 b and FIG. 19, the side walls 40 and 42 may be formed. Further details of the interbody fusion device 10 are described in commonly-assigned US Pat. No. 5,637,033 issued on Mar. 12, 2013, which is hereby incorporated by reference in its entirety.

  Details of the insert 16 are illustrated in FIGS. 6a-6e. The insert 16 includes an elongated generally flat body portion 200 having an upper surface 202 and a lower surface 204, both of which provide a stable stack within the interbody fusion device 10 after the insert 16 is expanded. It is generally planar to form and is substantially parallel. The insert 16 includes a posterior rear proximal end 206 and an anterior front distal end 208. The main body 200 is generally formed to have a U-shaped horseshoe-shaped configuration, and a pair of arms 212 and 214 facing each other with a gap projecting rearward from the base 205, penetrating the rear end 206, and A generally U-shaped opening 216 that faces rearwardly through the upper surface 202 and the lower surface 204 is defined. The width of the main body 200 between the side surfaces 212a and 214a is such that the side wall 40 of the lower end plate 14 and the inner surfaces 40a and 42a of the lower end plate 14 fit relatively tightly as shown in FIG. 5b. Can be dimensioned to move. Such careful sizing reduces the likelihood that the insert 16 within the cavity 48 of the lower endplate 14 will move laterally upon introduction of the insert. A surface 218 between the upper surface 202 and the lower surface 204 at the base 205 of the opening 216 defines a pressing surface to receive the drive of the inserter 10, as will be described. An opening 216 at the rear end of each insert 200 allows the bone graft material to flow into the device 10 and pass through the insert opening 216 and through the upper end plate 12 and the lower end plate 14 respectively. 60 so that it can flow into 60. A pair of inclined surfaces 208 a extends upward from the lower surface 204 on each side adjacent to the front distal end 208 and communicates with the lower surface 204.

  The insert 16 has features for interlocking engagement with an elevator 18 that connects and cooperates in a complementary fashion. As will be described, the distal front end 208 of the insert body 200 includes a latch receptacle 220 defined therein by a pair of spaced opposing arms 222a and 222b, in which an elevator is located. 18 accepts a flexible latch 318 (FIGS. 7a-7e). The arms 222a and 222b include locking surfaces 224a and 224b that protrude inward to engage and cooperate with and lock the elevator latch 318, respectively. Unlike the insert described in U.S. Patent No. 6,057,056, the lifting function is provided by the inserter 100 in conjunction with the elevator 18 herein, so that the insert 16 described herein has a top endplate. 12 and the lower endplate 14 or the interbody fusion device 16 does not function to assist in the subsequent separation of the insert 16. The insert 16 described herein is contemplated to be formed from a biocompatible material that is sufficiently rigid to form a sturdy stack when successive inserts are inserted into the device. . Thus, in one particular embodiment, the insert 16 is formed from PEEK or carbon fiber reinforced PEEK, or similar polymer material.

  Referring now to FIGS. 7a-7e, details of the elevator 18 are shown. The elevator 18 comprises an elongated, generally flat body 300 that has an upper surface 302 and a lower surface 304, both generally planar and substantially parallel. The elevator 18 has a thickness slightly greater than the thickness of the insert 16 between the upper surface 302 and the lower surface 304. As such, as indicated below, when the thickness of the insert 16 is, for example, 1.0 mm, the thickness of the elevator 18 may be 1.03 mm. The elevator 18 includes a rear rear proximal end 306 and a front front distal end 308. The elevator body 300 is formed to have a generally U-shaped horseshoe configuration similar to that of the insert 16. The elevator body 300 includes a pair of opposed arms 312 and 314 that project rearwardly from the base 305, pass through the rear end 306, and face rearwardly through the upper surface 302 and the lower surface 304. A generally U-shaped opening 316 is defined. Base 305 has a rear-facing surface 305 a that communicates with opening 316. An opening 316 at the rear end of the elevator 18 allows bone graft material introduced into the device 10 to flow through the insert opening 216 of the insert 16 and through the upper endplate 12 and the lower endplate 14 respectively. Are provided so that they can flow into the openings 38 and 60. The rear proximal end 306 includes inclined surfaces 312 a and 314 a that extend downward from the upper surface 302 and at the free end of each arm 312 and 314 in communication with the upper surface 302, respectively. The rear proximal end 306 further includes inclined lift surfaces 312b and 314b, respectively, extending upward from the lower surface 304 and at the free end of each arm 312 and 314 communicating with the lower surface 304. The front distal end 308 includes an inclined lift surface 308 a that extends upwardly from the lower surface 304 and communicates with the lower surface 304 adjacent to the base surface 305 a. The inclined raising / lowering surfaces 312b, 314b, and 308a form substantially the same angle in the same direction. The elevating surfaces 312b, 314b, and 308a are inclined ramps having a plurality of contacts for contacting and cooperating with complementary surfaces of expansion components on the inserter 100 to lift the elevator 18, as will be described. Define. Inclined surface 308a is generally centered along the elongate axis of the elevator, while surfaces 312b and 314b are spaced on either side. Thus, the lift surfaces 308a, 312b, and 314b define three triangulation contacts. The elevator has a recess 310 that extends into the elevator base 305 on each side thereof. The recess 310 is sized to receive the rail 14b on the inner surface of the lower end plate 14, as described. In one particular embodiment, the elevator 18 is formed from a type 2 titanium alloy that may be anodized for lubricity. Other materials such as PEEK may also be used as the elevator 18 material.

  The distal front end of the elevator body 300 includes a flexible latch 318 that projects upward from the top surface 302. The latch 318 includes a pair of spaced apart, flexible arms 320a and 320b configured to bend toward each other. Flexible arms 320a and 320b include outwardly directed locking surfaces 322a and 322b, respectively, for receiving and cooperating within receptacle 220 of each insert 16, as shown in FIG. 5b. . After receiving the latch 318 into the receptacle 220, the locking surfaces 224a and 224b elastically engage the locking surfaces 322a and 322b, respectively. The latch 318 protrudes above the upper surface 302 and a height that is slightly greater than the thickness of the insert 16. The lateral width of the elevator body 300 between the side surfaces 312c and 314c of the arms 312 and 314, respectively, is pointed above between the inner surfaces 40a and 42a of the lower end plate 14, as shown in FIG. 5c. So that it fits and slides relatively closely.

  Referring now again to FIGS. 1a-1c and FIGS. 8 and 8a, details of the inserter 100 are described. The inserter 100 is elongated and has a distal end 100a and a frame 101 at the proximal end 100b. The trigger actuator 102 that expands the device 10 and inserts the insert 16 into the device 10 after expansion comprises a frame 101 at the proximal end 100b of the inserter. A plurality of inserts 16 are movably supported on the elongate track 104 by a linear arrangement so that they can be inserted one after another into the device 10. The track 104 supports at least one insert 16, for example, can support an array of five inserts 16, but with fewer or more inserts 16 supported as desired. Good.

  The distal end 100a is shown in detail in exploded view in FIGS. 8 and 8a. The inserter 100 includes an elongated track 104 and an outer elongated track cover 106 that is substantially rigidly coupled to the track 104. The track 104 is configured as a closed passage and is supported within the outer track cover 106. The cover 106 is fixed to the frame 101 so that it does not move, but in certain arrangements, the cover 106 can be removably attached to the frame 101 as described. The elongate guide pin 108 is supported in an opening 110 that extends longitudinally through the cover 106. The distal end 108a of the guide pin 108 has a thread for releasably screwing into and engaging in the opening 56 at the proximal rear end wall 44 of the lower end plate 14. The proximal end of the guide pin 108 includes a threaded knob 112 for pressing and releasably attaching the cover 106, thereby attaching the track 104 to the device 10. The track cover 106, in one arrangement, includes a pair of opposing pins 114, which in the rear wall 44 of the lower endplate 14 (FIG. 19) to assist in rigidly securing the inserter 100 to the device 10. Engage with the corresponding hole 58. It will be appreciated that other securing structures may be used to releasably attach the inserter 100 to the device 10. The track 104, in one embodiment, is formed from stamped stainless steel and the cover 106 is an extruded aluminum alloy. Stainless steel or strong reinforced plastic can also be used for the cover 106.

  The track 104 at the distal end 100a of the inserter 100 moves on the track 104 to move relative axially to slidably contact and cooperate with the elevator 18 to expand the device 10. An expansion component defined by an axially translatable lifting platform 116 that is supported is supported. The lifting platform 116 is elongated, generally flat, and has an upper surface 118 and a lower surface 120, both of which are generally planar and substantially parallel (FIG. 18). The lift platform 116 has a thickness dimensioned between the upper surface 118 and the lower surface 120 that is the same as the thickness of the elevator 18, ie, slightly greater than the thickness of the insert 16. The lifting platform 116 is supported by the inserter 100 for axial reciprocation in the protruding and retracting directions. As will be described, the proximal end of the lifting platform 116d is coupled to the trigger actuator 102 to provide such a protruding and retracting direction.

Elevating platform 116 includes an inclined elevating surface 116 a that projects axially slidably outward from track 104 and extends downwardly from upper surface 118 and communicates with upper surface 118 at its free distal end. In an arrangement spaced proximal of the lift surface 116a, the lift platform further comprises a pair of laterally spaced inclined surfaces 116b and 116c. The inclined elevating surfaces 116a, 116b, and 116c form an angle approximately equal to the angle of the inclined elevating surfaces 312b, 314b, and 308a of the elevator body 300 in the same direction. Inclined surfaces 116 a, 116 b, and 116 c define a ramp ramp having a plurality of complementary contacts for contacting and cooperating with elevator 18. Inclined surface 116a is generally centered along the elongate axis of lifting platform 116, while surfaces 116b and 116c are spaced on either side. Accordingly, the inclined surfaces 116a, 116b, and 116c are arranged to be in contact with and cooperate with the elevating surfaces 308a, 312b, and 314b when the elevating platform 116 is moved in the protruding direction, respectively, and three triangles spaced from each other. Define survey contacts. Elevating platform 116, in particular inclined surfaces 116 a, 116 b, and 116 c, are coded to facilitate slidable contact with elevator 18 for expansion of device 10, or otherwise suitable in some other manner. Various lubricants. If the lifting platform 116 is made from stainless steel, for example, such a lubricant may include a molybdenum disulfide (MoS ₂ ) material.

  Still referring to FIGS. 8 and 8 a, the inserter 100 further supports a drive device 124 at its distal end 100 a for axial translation within the track 104. As will be described, the proximal end 124 a (FIG. 8) of the drive device 124 is coupled to the trigger actuator 102 and causes the drive device 124 to translate. The distal end of the drive 124 enters the opening 216 of the insert body 200 and engages the hold-down surface 218 to move the insert 16 from the track 104 when the drive 124 is moved axially distally. 10 is provided with a pressing surface 124b that is sized and configured to be pushed into 10. Further, the driving device 124 includes an upper surface 124c that supports the insert 16 so as to be movable in a linear arrangement. Further, as shown in FIG. 8, in cooperation with the driving device 124, the positioning should be performed so as to contact the pressing surface 124b of the driving device individually while preventing the retrograde of the insert 16 when positioned. Also included is an indexing member 125 that progressively moves the insert 16 distally in the protruding direction.

  Still referring to FIG. 8 a, the inserter 100 comprises a flexible graft shield 128 that projects distally from the inner track 104. The graft shield 128 is not supported at the opposite end 128b but is supported at the one end 128a by a cantilever system that can be bent freely. Graft shield 128 is elongate and generally flat so as to substantially block communication between opening 38 through upper end plate 12 and insert 16 slidably inserted into device 10. Size is determined and configured. As will be described, the graft shield 128 is configured to penetrate into the device 10 through a passage 50 between the upper endplate 12 and the expanded structure adjacent the lower surface 30 of the upper endplate 12.

  Next, the trigger actuator 102 of the inserter 100 and its operating mechanism and function will be described in detail with reference to FIGS. 9 and 9a to 9b. The trigger actuator 102 includes a pair of hand grips 132 and 134 that are biased and separated by an expansion spring 136. The hand grip 132 is fixed to the frame 101 of the inserter 100 so as not to move. The hand grip 134 is pivotally connected to the frame 101 at the pivot portion 138 and is movable toward the hand grip 132 against the bias of the expansion spring 136 by hand pressure. The handgrip 134 has gear teeth 140 that interface with a gear rack 146 that is slidably coupled to the frame 101. The gear mechanism is sized to provide an appropriate translation of the gear rack 146 in the protruding direction when the trigger actuator 102 is actuated. Also, slidably coupled to the frame 101 is configured to articulate with a drive slide 150 that is configured for relative articulation with the drive device 124 and a lifting platform 116. The elevating slide 154. The gear rack 146 includes a lower surface 146a that defines a tooth pattern, an upper surface 146b that defines a retainer surface 146d, a ramp surface 146e, and a distal end 146c. The distal end 146c includes a pawl 148 that is configured to provide limited rotation about the pivot 148a, with the distal end of the pawl 148 biased toward the drive slide 150 by a compression spring 152. The Prior to actuation of the trigger 102, the pawl 148 is constrained from rotating around the pivot 148 a by the lower surface 150 a of the drive slide 150. After the first actuation of the trigger 102, and thus after translation of the gear rack 146 in the protruding direction, the pawl 148 slides along the lower surface 150 a under the bias of the compression spring 152. When sufficient translation of the gear rack 146 occurs and the pawl 148 passes the distal end of the drive slide 150, the pawl 148 rotates counterclockwise as shown in FIG. 9a. Rotates around and moves to a position limited by contact with the top surface 146f of the gear rack 146.

  The pawl 148 includes a pressing surface 148b sized to engage the pressing surface 154a at the proximal end of the lift slide 154. Furthermore, actuation of the trigger 102 facilitates contact of the holding surfaces 148b and 154a, and thus movement of the lifting slide 154 and lifting platform 116 in the protruding direction, causing expansion of the device 10.

  The lift slide 154 further comprises a proximal elongate anchoring portion 154b sized so that the hold-down surface 154c engages the hold-down surface 150b at the proximal end of the drive slide 150. After the elevating slide 154 is translated in the protruding direction, the pressing surface 154c engages with the pressing surface 150b for joint translation between them.

  The drive slide 150 further includes an upper raised feature 156 that defines pressing surfaces 156a and 156b that are sized to fit within the slot 124d (FIG. 8) of the drive device 124. The slot 124d includes pressing surfaces 124e and 124f that are spaced apart from each other in a complementary axial direction. The length of the slot 124d is such that translation of the drive slide 150 during the first actuation of the trigger 102 does not induce contact between the pressing surfaces 156b and 124f and thus does not result in translation of the drive device 124. The size is decided.

  The drive slide 150 further includes a pawl 158 configured to provide limited rotation about the pivot 158a, with the proximal end of the pawl at the side of the gear rack 146 by bilateral torsion springs (not shown). It is urged towards. Prior to actuation of the trigger 102, the pawl 148 is constrained from rotating about the pivot 158 a by a protruding surface 160 that is rigidly coupled to the frame 101. After the drive slide 150 is translated in the protruding direction, the claw 158 slides along the upper protruding surface 160 under the bias of the torsion spring. When sufficient translation of the drive slide 150 occurs and the pawl 158 passes the distal end of the protruding surface 160, the pawl 158 rotates counterclockwise around the pivot 158a as shown in FIG. 9a. And move to a position limited by contact with the lower surface 150c of the drive slide 150. Such translation is slightly longer than the translation required by the lifting platform 116 to achieve full expansion of the device 10 so that the pawl 158 does not rotate when the device 10 is not fully expanded. Configured as follows. Further, rigidly coupled to the pawl 158 to rotate together are double-sided flags 162 positioned in the slots 163 in the frame 101 (FIG. 1a), and these flags 162 can be seen from both sides of the frame 101. Projects outward in the direction. After articulation of the pawl 158 and flag 162, the user is visually aware of the position of the drive slide 150 and the lift slide 154, thereby achieving full expansion of the device 10, introducing additional inserts. The user knows that he cannot get it.

  The pawl 158 is a ramp that is sized to engage a retaining surface 158b that is sized to engage the retaining surface 146d of the gear rack 146 and a ramp surface 146e of the gear rack 146. A surface 158c. Following full actuation of trigger 102 and full stroke and release of grip pressure, gear rack 146 and handgrip 132/134 are returned under the bias of expansion spring 136. As the gear rack 146 is retracted, the associated ramp surfaces 146e and 158c collide, causing the pawl 158 to rotate clockwise, thereby allowing the gear rack 146 to pass. After the gear rack 146 is sufficiently translated in the retracting direction so that the ramp surface 146e has already passed through the proximal edge of the ramp 158c, the pawl 158 rotates counterclockwise around the pivot 158a. Thus, the drive slide 150 returns to a position limited by contact with the lower surface 150c.

  After completion of the first actuation of the trigger 102 and completion of the first stroke, the lift platform 116 remains protruding and maintains the expanded state of the device 10, and its drive slide 150 is anchored to the lift slide 154. It will be understood that it remains partially protruding due to 154b. Note that the pawl 158 remains in a rotational state limited by contact with the drive slide 150, but the pawl 148 returns to its original collapsed state limited by the lower surface 150a of the drive slide 150. .

  After the second actuation of the trigger 102, the gear rack 146 again protrudes so that the press surface 146d contacts the press surface 158b of the pawl 158, causing joint translation of the gear rack 146 and the drive slide 150. Translate to. After further actuation, the pressing surface 156b of the drive slide 150 contacts the pressing surface 124f of the drive device 124, causing a joint translation between them, thereby inserting at the completion of the second stroke of the trigger actuator 102. Engage with the holding surface 218 of the object 16 to push the insert 16 from the track 104 into the device 10.

  A cam 164 and a gear 166 are provided for the purpose of returning the truck lifting platform 116 to its original position in the retracted direction. The gear 166 is joined to a second gear rack 154 d that is rigidly connected to the lower surface of the elevating slide 154. The cam 164 is coupled to the gear 166 for counter rotation between them, and after the insert 16 is partially inserted into the device 10, with the notch 170 (FIG. 8 a) in the drive 124. Positioned to contact. In addition, the trigger is activated to return the lifting platform 116 to its original position, but the drive inserts more inserts 16. When full triggering is achieved, the gear rack 146 and handgrip 132/134 are returned under the bias of the expansion spring 136. To manually reset the position of drive slide 150, the user pulls up on both side tabs 162b that are rigidly coupled to flag 162, thereby causing rotation of pawl 158 and translation of drive slide 150 in the retracted direction. . Due to the rotational state of the flag 162 and the pawl 158, the drive slide 150 can be returned to its original retracted position by the rotation of the pawl 158 limited by the protruding surface 160. Bidirectional ratchet mechanism 168 prevents unwanted movement of drive slide 150 in the wrong direction. If full expansion of the device 10 is achieved and the surgeon prefers to interrupt the operation without further introduction of the insert 16, a hex fitting 174 (FIG. 1a) coupled to the gear 166 may be replaced with a hex wrench or other It can be actuated by a suitable tool. The rotation of the fitting 174 causes the gear 166 to rotate, which translates the lifting slide 154 directly, thus translating the lifting platform 116 proximally and expanding the device 10 with no insert 16 introduced. To release.

  Thus, it should be understood how the trigger actuator 102 operates to expand the device 10 and introduce one or more inserts 16. In the first stroke, only the lifting platform 116 translates in the protruding direction, causing the device 10 to expand. The drive device 124 remains stationary throughout the first stroke. After the handgrip 132/134 is completed in the first stroke and returned to the starting position under the bias of the expansion spring 136, the lifting platform 116 expands the device 10 when the handgrip 132/134 returns. It remains stationary at the protruding position that maintains the state. In the second stroke of the trigger actuator 102, the drive device 124 is translated in the protruding direction while the lifting platform 116 is initially stationary in the protruding direction. When the drive 124 partially inserts the insert 16 into the expanded device 10, the continuous movement of the trigger actuator 102 causes the lifting platform 116 to be retracted in the retracting direction. As the lifting platform 116 retracts, the drive 124 continues to advance in the protruding direction, pushing the insert 16 fully in place after the second stroke is complete.

  Thus, for the specific device described for insertion into the intervertebral disc space in the posterior approach, expansion of the device 10 is accomplished in the first stroke of the trigger actuator 102 and complete insertion of the insert 16 Is achieved at the completion of the second stroke. For longer devices, such as devices that can be inserted from a side access path, the mechanism of the inserter 100 is such that the longer device is expanded on the first stroke and the insert 16 is expanded on the second stroke. And can be adjusted to be fully inserted in the third stroke. Accordingly, those skilled in the art will appreciate that the stroke used to expand the device 10 and the number of insertions of the insert 16 into the expanded device 10 can be varied by suitable adjustment of the operating mechanism of the trigger actuator 102. Will be done. Such adjustment may include, for example, changing the number of retaining surfaces 146d provided on the gear rack 146 to engage the pawl 158.

  Referring now to FIGS. 10a-10b and FIGS. 11-12, the assembly of device 10 and inserter 100 is described. The upper end plate 12 and the lower end plate 14 are assembled to the inserter 100 in an unexpanded state, and the upper end plate 12 is completely contained in the cavity 48 of the lower end plate 14. In such a state, the elevator 18 moves between the upper end plate 12 and the lower end plate 14 as described above and shown in FIG. 5c for independent movement along the direction 130 of expansion. Captured and held. The inserter 100 is releasably attached to the device 10 after the guide pin 108 is threaded and engaged into a threaded opening 56 in the proximal rear end wall 44 of the lower endplate 14. Graft shield 128 penetrates into device 10 through passage 50 between upper end plate 12 and elevator 18 adjacent to lower surface 30 of upper end plate 12. With the inserter 100 secured to the device 10, the lifting platform 116 and the drive 124 are axially translatable relative to the device 10 in the protruding and retracting directions. In this unexpanded state, there is no insert 16 in the device 10. In the arrangement described, there are five inserts 16 supported on the track 104 in a linear array.

  In the positions illustrated in FIGS. 10 a-10 b and FIGS. 11-12, the lifting platform 116 is in a retracted position relative to the device 10 and the elevator 18. The insert 16 is disposed on the track 104 such that it can be inserted into the device 10 outside the device 10 as shown in FIG. 10a. In this position, the lower surface 120 of the lifting platform 116 is placed on the lower inner surface 54 of the lower end plate 14. Similarly, the lower surface 304 of the elevator 18 is supported by the lower inner surface 54 of the lower end plate 14. As such, the lifting platform 116 and the elevator 18 are in substantially the same plane, and the upper surface 118 of the lifting platform 116 is substantially in the same plane as the upper surface 302 of the elevator 18. With the inserter 100 attached to the device 10, the elevator 18 is fixed axially with respect to the axial movement of the lifting platform 116.

  In the state shown in FIGS. 10 a-10 b, the apparatus 1 comprising the unexpanded device 10 releasably attached to the inserter 100 is in the intervertebral disc space between two opposing vertebral body parts. When the device 10 is inserted into the device, it can be used immediately. Prior to insertion, the opening 38 through the upper endplate 12 may be pre-filled with a suitable bone graft material to facilitate fixation of the opposing vertebral body through the device 10. Graft shield 128 penetrates into device 10 through passage 50 between upper end plate 12 and elevator 18 adjacent to lower surface 30 of upper end plate 12 defining a pocket for receiving bone graft material. The free end 128b of the graft shield 128 is left unattached on the internal protrusion 12b of the upper end plate 12 adjacent to its distal end. Accordingly, the opening 38 is open adjacent to the outer surface 12 a of the upper end plate 12 and is closed by the graft shield 128 adjacent to the lower surface 30. As such, the graft shield 128 forms a barrier between the bone graft material and the elevator 18 and insert 16 that are inserted into the device 10 upon expansion. Pre-filling the bone graft material into the opening 38 on the graft shield 128 advantageously allows for a reduction in the introduction of bone graft material in situ, so that sufficient bone graft material is present throughout the device 10. Through and through the upper endplate 12 and the lower endplate 14 to be received in the openings 38 and 60, further ensuring that the opposing vertebral body is placed under stress. In addition, the graft shield 128 is slidable on the insert 16 during expansion and can interfere with the expansion of the device 10 or can be hindered by the bone graft material on the sliding interface. By substantially preventing interference with proper insertion, a barrier is formed that substantially prevents the bone graft material in the opening 38 from being disturbed.

  At this point in the surgical procedure, the inserter 100 is used to insert the unexpanded device 10 into the intradisc space. The device 10 can be implanted into the spine from the posterior or posterior lateral, bilaterally or unilaterally, or with an anterior or lateral approach, as described above, depending on surgical instructions and surgeon preference. . Then, after the device 10 has been inserted into a suitable location in the intervertebral disc space, the actuator 102 as described above is operated in a first actuation. Initially, in the first stroke, the lifting platform 116 is translated axially while the drive 124 remains stationary. The lifting platform 116 moves in a protruding direction from the retracted position of FIGS. 10 a-10 b, thereby moving the lifting platform 116 further into the device 10. When moving in the protruding direction, the lift surfaces 116a, 116b, and 116c of the lift platform 116 are in contact with the associated lift surfaces 308a, 312b, and 314b of the elevator 18, respectively. In the associated engagement, the elevator 18 moves in the direction of expansion, moves away from the lower inner surface 54 of the lower end plate 14, and moves toward the upper end plate 12. The upper surface 302 of the elevator 18 is in contact with the lower surface 30 of the upper end plate 12, and the elevator 18 is slidably moved along the rail 14b as shown in FIGS. 13a to 13b. 12 toward the expansion direction and away from the lower endplate 14 thereby expanding the device 10.

  When full expansion of the device 10 is achieved, as described above, the first stroke of the trigger actuator 102 is complete and the handgrip 132/134 is returned to its original starting position. The trigger actuator 102 is then operated in a second operation to initiate a second stroke. When the second stroke begins, the lifting platform 116 remains stationary, holding the device 10 in an expanded state, during which time the axial translation of the drive 124 begins. As shown in FIGS. 13 a-13 b, the continued operation of the actuator 102 is such that the distal front end 208 is adjacent to the upper end plate 12 and the proximal end of the device 10 with the distal front end 208 of the insert 16. Push the insert 16 distally to move freely through the passage 50 and into the expanded device 10 until it is partially inserted into the expanded device 10 with the lower endplate 14.

  With the insert 16 partially inserted into the device 10, the continued operation of the actuator 102 during the second stroke causes the lifting platform 116 to move proximally, thereby moving the lifting platform 116 in the retracting direction. Cause to do. With the distal front end 208 of the insert 16 supporting the upper end plate 12, continued proximal movement of the lifting platform 116 causes the lifting surfaces 116 a, 116 b, and 116 c of the lifting platform 116 to each of the elevators 18. Causing the associated lift surfaces 308a, 312b, and 314b to fully disengage, the elevator 18 moves away from the upper end plate 12 in the expansion direction and moves along the rail 14b toward the lower end plate 14, FIG. -Allows to return to the position of the elevator 18 shown in Fig. 10b. When the elevator 18 returns to a position where the lower surface 120 of the lift platform 116 is placed on the lower inner surface 54 of the lower endplate 14, a space such as a space 64 as described below with reference to FIG. , Formed between the lower surface 30 of the upper end plate 12 and the upper surface 302 of the elevator 18. Such a space between the upper end plate 12 and the elevator 18 is slightly larger than the thickness of the insert 16 and communicates directly with the lower surface 30 of the upper end plate 12 and the upper surface 302 of the elevator 18. Upon completion of the second stroke of the actuator 102, the drive 124 continues to move axially and slidably distally to move the insert 16 into such space of the expansion device 10 as shown in FIG. Pushing completely in, the lower surface 204 of the insert 16 faces the upper surface 302 of the elevator 18 and slidably contacts it. The drive 124 is retracted proximally to the original position shown in FIGS. 10a-10b when the hand grip 134 of the actuator 102 is released.

  When the insert 16 is inserted into the device 10, the receptacle 220 described above at the distal end 208 of the insert 16 has locking surfaces 224a, 224b, and 322a, 322b shown in FIG. 5b. The complementary flexible latch 318 on the upper surface 302 of the elevator 18 is received and coordinated so as to be elastically interlocked. Such interlocking substantially resists retraction of the insert 16 through the passage 50 when the drive 124 is withdrawn from the insert 16 in the retracted position. If the device 10 is further expanded, the initial insert 16 is moved upward with the upper endplate 12 by the elevator 18 as described below. Then, when the elevator 18 returns downward toward the lower endplate 14, as will be described, the latch 318 is separated from the receptacle 220 when the space 64 is formed. When the initial insert 16 is moved upward, it is placed over the passage 50 and held in a state of being captured by the inner surface of the lower end plate 14, including the inner surface 44 a of the rear end wall 44. An interlocking structure between the insert 16 and one or more inner surfaces of the lower endplate 14 while the insert 16 is held in place within the device 10 by interlocking of the receptacle 220 and latch 318, or It will be appreciated that other structures can be provided that resist the backward movement of the insert 16, such as interlocking structures between adjacent inserts 16. After completing the insertion of the insert 16, the opening 216 of the insert 16 is at least partially aligned with the opening 316 of the elevator 18, the opening 38 of the upper end plate 12, and the opening 60 of the lower end plate 14. The After the inserter 100 is removed from the expanded device after completion of the surgical procedure, the insert opening 216, elevator opening 316, and graft chambers 38 and 60 are each at least partially aligned. And communicate with each other.

  If the surgeon determines that an additional insert 16 is required to make an appropriate correction for the height of the disc space, 1 in the same manner as described for the insertion of the first insert 16. Actuator 102 may be manipulated to insert one or more additional inserts 16. 15a-15b shows the first actuator 102 by the elevator 18 after one insert 16 has been inserted and the device 10 has been lifted by the lifting platform 116 in the same process as described with respect to FIGS. 13a-13b. The device 10 is shown in which the second insert 16 is partially introduced after further expansion in the stroke. As the second insert 16 enters the further expanded device 10 in the second stroke, the lifting platform 116 is pulled proximally in the retracting direction to lift the lifting surfaces 116a, 116b, and 116c of the lifting platform 116. Are fully disengaged from the associated lift surfaces 308a, 312b, and 314b of the elevator 18, respectively, allowing the elevator 18 to freely return to the inner surface 54 of the lower end plate 14. However, if the elevator 18 cannot fully or partially return to such position when the drive 124 pushes the second insert 16 into the device 10, the second insert 16's An inclined surface 208a adjacent to the front distal end 208 contacts the inclined surfaces 312a and 314a at the upper free end of each arm 312 and 314 of the elevator 18, respectively, as shown in FIGS. 16a-16b. Then, the elevator 18 is urged toward and brought into contact with the lower surface 54 of the lower end plate 14 to form a space 64 between the lower surface 204 of the first insert 16 and the upper surface 302 of the elevator 18. Alternatively or in addition, a suitable biasing element may be included to normally bias the elevator 18 toward the inner surface 54 of the lower endplate 14. The lower endplate 14 is provided with a lip 46a on the front end wall 46 adjacent to the distal end of the cavity 48 to accommodate a spring 107 acting as a biasing element, for example as shown in FIG. 15a. Can be formed. It will be appreciated that the feature that biases the elevator 18 toward the lower inner surface 54 of the lower endplate 14 functions upon insertion of the first insert 16 and all subsequently inserted inserts 16. I will.

  By continuously operating the actuator 102 in the second stroke, the second insert 16 continues to move until it is fully inserted as shown in FIG. When the second insert 16 is inserted into the device 10, the resilient interlocking feature of the receptacle 220 described above the second insert 16 is flexible on the distal end of the elevator 18. And interlock with the interlocking features complemented by the latch 318. After completion of the insertion of the second insert 16, the opening 216 of the insert 16 is connected to the opening 216 of the first insert, the opening 38 of the upper end plate 12, and the opening 60 of the lower end plate 14. They are at least partially aligned and all communicate after removal of the inserter 100. The second insert 16 is the bottom insert and is directly under the first insert 16 and in contact with the first insert 16 as shown in FIGS. Is placed on the upper surface 302 of the elevator 18. The drive 124 is then retracted proximally again to the original position shown in FIGS. 10a-10b when the hand grip 134 of the actuator 102 is released.

  When the intervertebral disc space is expanded to its maximum anatomical extent, and the spine reaches ligament taxis and the device 10 cannot expand further, the surgeon determines such a condition by tactile feedback. can do. Insertion of the insert 16 into the device 10 can only be accomplished after the elevator 18 has reached its final movement in the direction of expansion towards the upper end plate 12. As such, if the handgrip 132/134 cannot be compressed in a manner that completes the first stroke of the actuator 102, the surgeon has reached ligament taxis and the proper intervertebral disc height has been restored. Can be recognized. Incomplete insertion of the insert 16 can be avoided to the extent that insertion of the insert 16 allows expansion of the device 10 after complete movement of the elevator 18 in the expansion direction towards the lower endplate 14. An indication that the device 10 has reached full expansion can also be determined visually as described above by the observation that the flag 162 on the actuator 102 is rotating with respect to the frame 101. The surgeon then terminates the surgery by actuating the hex fitting 174 as described above. The inserter 100 is then removed from the expanded device 10 by rotatably removing the knob 112 from the proximal end of the guide pin 108. As shown in FIG. 19, the guide pin 108 remains releasably connected to the expanded device 10 and serves as a locator for subsequent attachment to an apparatus for housing a suitable bone graft. Assists in delivering such material into the passage 50 of the lower endplate 14 through which the 16 is inserted. As such, after removal of the inserter 100 from the expanded device 10, a substantially unobstructed path passes from the passage 50 through the opening 316 of the elevator 18 and the opening 216 of the insert 16. Enter the openings 38 and 60 that penetrate the upper endplate 12 and the lower endplate 14, respectively, and bone graft material is introduced into the expanded device 10 through the flow path 50 and completely within the device 10, respectively. Allows to flow.

  According to some specific applications of the device 10 for posterior implantation as described above, the total length of the device 10 as defined by the length of the lower endplate 14 is about 25 mm. The width of the device 10 is about 10 mm. The height of the unexpanded device 10 of FIGS. 1a-1c in which the upper end plate 12 is completely nested within the lower end plate 14 is about 7 mm. With the introduction of five inserts 16 each having a thickness of about 1.0 mm, the height of device 10 can be expanded from an unexpanded height of about 7 mm to an expanded height of about 12 mm. It will be appreciated that these dimensions are exemplary only and that the number of inserts 16 and the dimensions of device 10 may vary depending on the particular surgical procedure and application. For example, the device 10 for posterior implantation has an unexpanded initial height in the range of about 7-10 mm, a width in the range of about 10-14 mm, and a length in the range of about 20-35 mm. Good, up to 16 or 8 inserts for higher sizes. In order to implement such a later sized device 10, the trigger actuator 102 expands the device 10 in a first stroke and fully inserts the insert 16 in a second stroke. It may have an operating mechanism as described.

  For some applications of the device 10 that can be implanted from the outer approach, the device 10 has an unexpanded height in the range of about 8-10 mm, a width in the range of about 14-26 mm, and about 35- It may have a length in the range of 60 mm. To implant such a device 10 from the outer approach path, the trigger actuator 102 expands the device 10 in a first stroke, partially inserts the insert 16 in a second stroke, and in a third stroke. It may have an operating mechanism adjusted to fully insert the insert 16.

  The passage 50 through the back end wall 44 facilitates the introduction of suitable bone graft material by a bone graft delivery device that can use the guide pin 108 as a positioning tool, as shown in FIG. The size is determined and configured as follows. Such a bone graft delivery device may have an entry tip sized and configured to enter the passageway 50. In certain arrangements, it may be desirable to increase the entry opening to further facilitate the delivery of bone graft material. In such a case, a portion of the rear end wall 44 can be notched out to form an increased passage portion 50a directly below the threaded opening 56. A passage portion 50a located below the threaded opening 56 guides the incoming flow of bone graft material into the center of the expanded device 10. The passage portion 50a may be suitably configured to receive and cooperate with the entry tip of the bone graft delivery device, such passage portion 50a being rectangular, square, or arcuate. In the example device 10 for rear applications, the passage portion 50a may be specifically configured to be square. If such a device 10 has an unexpanded initial height of 7 mm and a width of 10 mm, the passage portion 50 a has a width of 3 mm and a height of 3 mm measured perpendicularly from the inner surface 54. Can do. In the example device 10 for external applications, the passage portion 50a may be specifically configured to be generally rectangular. If such a device 10 has an unexpanded initial height of 8 mm and a width of 16 mm, the passage portion 50 a has a height of 3 mm and a width of 6 mm, measured perpendicularly from the inner surface 54. Can do. For the purpose of delivering bone graft material in the form of an autograft, the minimum dimension of the passage portion 50a, or a portion of the passage 50 used as an entrance to such autograft material, is about 2 mm or more. It is desirable to be. However, it will be understood that such minimum dimensions may vary depending on the viscosity of the bone graft material to be delivered.

  Referring now to FIG. 20, an alternative inserter 400 that implements a modular structure is described. The inserter 400 includes an actuator 402 and a releasable cartridge 404. Actuator 402 includes a pair of handgrips 407 and 408 that are biased away by an expansion spring in the same manner as trigger actuator 102 described above. The actuator 402 includes a frame 410 that houses an operation mechanism 411 that is substantially the same as the operation mechanism of the trigger actuator 102. The grip 407 is fixed to the frame 410 so as not to move, but the grip 408 is pivotally connected to the frame 410 by a pivot pin 412. The frame 410 supports a rotatable flag 414 that is coupled to the operation mechanism 411 as the trigger actuator 102. The frame 410 includes a pair of spring-loaded flexible latches 416 that protrude upwardly from the mating surface 410a adjacent to the proximal end 410b of the frame 410. Adjacent the distal end 410c of the frame 410 is a support surface 410d. The actuator 402 in certain embodiments is reusable. Frame 410, and also frame 101, and handgrips 407, 408, and handgrips 132, 134 are all formed from stainless steel in a particular arrangement, but other materials such as aluminum alloys and plastics are also possible. Can be used.

  The cartridge 404 includes a track 406 housed in an outer cover 418 similar to the track 104 and cover 106 of the trigger actuator 102. The cartridge 404 is similarly fabricated in the same manner as the lifting platform 116, the drive 124, and the indexing member 125 of the trigger actuator 102 and functions in the same manner. And an indexing member (all not shown). A support 420 comparable to the support 172 is fixed to the bottom of the cover 418. The cartridge 404 supports a plurality of inserts 16 that are in a linear array for insertion into the expandable device 10. A cooperating latch structure is provided on the bottom surface of cover 418, thereby releasably engaging latch 416 of actuator 402. In one particular embodiment, the cartridge 404 is disposable.

  The cartridge 404 initially engages the support 420 with the support surface 410d on the frame 410 and then rotates the cartridge down until the latch 416 is releasably attached to the associated latch structure at the bottom of the cartridge 404. And releasably attached to the frame 410 by pointing toward the proximal end 410b. After the cartridge 404 is attached to the actuator 402, the components of the operating mechanism 411 join the drive and lift mechanism in the track 406 in a manner comparable to the actuator 102, which is the same as the slot 124d of the drive 124. Receiving a raised feature 422 (same as raised feature 156) in the slot. The cartridge 404 can be released from the actuator 402 by actuating a release lever 424 that is supported on both sides by the frame 410 and is movably coupled to a latch 416. In all other respects, the modular inserter 400 operates in the same manner as the trigger actuator 102 described above.

  While the invention has been illustrated and described in detail in the drawings and foregoing description, the illustration and description are to be considered illustrative and not restrictive in nature. It will be appreciated that only the preferred embodiments have been presented and that all changes, modifications and further applications within the spirit of the invention should be protected. For example, an inserter comprising a graft shield, such as shield 128, can be used with an expandable interbody fusion device having an expanded structure without an elevator 18 as described above. For example, an inserter comprising a graft shield 18 may be used with the expandable interbody fusion device shown and described in US Pat. It will be expanded after the introduction of the wafer. The shield 128 may be used as described herein, with a barrier between bone graft openings through one of the endplates, such as the upper endplate and the wafer. Provide. Such a barrier substantially prevents the bone graft material prefilled in such openings from interfering with the sliding acceptance of such wafers during device insertion and expansion. In addition, it will be appreciated that actuators other than trigger actuators, including threaded rotation mechanisms and the like, may be used with the inserter 100 described herein.

DESCRIPTION OF SYMBOLS 1 Apparatus 10 Expandable spinal interbody fusion device 12 Upper end plate 12a Upper outer surface 12b Lower protrusion 14 Lower end plate 14a Lower outer surface 14b Rail 16 Insert 18 Elevator 20 Hub 22, 24 Side surface 26, 28 Cross section 30 Lower surface 38 Opening 40, 42 Side wall 40a, 42a Inner surface 44, 46 End wall 44a Inner surface 46a Lip portion 48 Cavity 50 Insert passage 50a Passage portion 54 Lower inner support surface 56 Threaded connection opening 58 Hole 60 Opening 100 Inserter 100a Distal end 100b Proximal end 101 Frame 102 Trigger actuator 104 Track 106 Outer elongated track cover 107 Spring 108 Guide pin 110 Opening 112 Threaded knob 114 Pin 116 Lift platform 116a Inclined lift surface 116b, 11 6c Inclined surface 116d Elevating platform 118 Upper surface 120 Lower surface 124 Driving device 124c Upper surface 124d Slot 124e, 124f Holding surface 125 Index member 128 Graft shield 128a One end 128b Free end 132, 134 Hand grip 136 Extension spring 138 Pivoting portion 140 Gear teeth 146 Gear rack 146a Lower surface 146b Upper surface 146c Distal end 146d Holding surface 146e Ramp surface 146f Upper surface 148 Claw 148a Pivoting portion 148b Holding surface 150 Driving slide 150a Lower surface 150b Holding surface 150c Lower surface 152 Slide spring 154 Slide surface 154 Elongate anchoring portion 154c holding surface 154d rack of second gear 156 upper raised feature 156a, 156b holding 158 Claw 158a Pivoting portion 158b Holding surface 158c Ramp surface 160 Projecting surface 162 Both sides flag 162b Both sides tab 163 Slot 164 Cam 166 Gear 168 Bidirectional ratchet mechanism 170 Notch 172 Support body 174 Hexagon fitting 200 Main body portion 202 Upper surface portion 202 Upper surface portion 204 Upper surface portion 204 Rear rear proximal end 208 Front front distal end 208a Inclined surface 212, 214 Arm 212a, 214a Side surface 216 Generally U-shaped opening 218 Surface 218 Holding surface 220 Latch receptacle 222a, 222b Arm 224a, 224b Locking surface 300 Elongated, generally flat body 302 Upper surface 304 Lower surface 305 Base 305a Rear facing surface 306 Rear rear proximal end 308 Front front distal end 308a Inclined lifting surface 10 Depressions 312 and 314 Arms 312a and 314a Inclined surfaces 312b and 314b Inclined ascending and descending surfaces 312c and 314c Side surfaces 316 Openings 318 Latches 320a and 320b Arms 322a and 322b Locking surfaces 400 Inserters 402 Actuators 404 Cartridges 406 Tracks 407 and 408 Hands Grip 410 Frame 410a Joint surface 410b Proximal end 410c Distal end 410d Support surface 411 Operating mechanism 412 Pivot pin 414 Flag 416 Spring loaded flexible latch 418 Outer cover 420 Support 422 Raised feature

Claims (15)

  An inserter for dilating an expandable spinal interbody fusion device and inserting an insert therein
  Frame,
  An elongated lifting platform movably supported by the frame to expand the expandable spinal interbody fusion device;
  An elongate drive movably supported by the frame for inserting an insert into the expandable spinal interbody fusion device, the drive moving at least partially independent of the lifting platform A drive that is possible;
  An actuator supported by the frame and operatively coupled to the drive device to cause independent movement of the drive device and the lifting platform after its movement with respect to the frame;
With
  The inserter characterized in that the lifting platform is moved axially in the first stroke of the actuator and the drive is moved axially in the second stroke of the actuator.   The inserter according to claim 1, wherein the lifting platform is generally flat and has a distal free end protruding outwardly from the inserter.   The inserter of claim 1, further comprising a guide pin releasably connectable to the expandable interbody fusion device and removably connected to the inserter.   The inserter of claim 1, wherein the inserter further comprises a graft shield sized and configured to project from a distal end of the inserter and to penetrate into the expandable interbody fusion device. The inserter according to claim 1 , wherein the elongate lifting platform is moved entirely through the first stroke while the drive remains stationary. 6. The inserter according to claim 5 , wherein the drive is moved exclusively during a portion of the second stroke while the elongate lifting platform remains stationary. The inserter according to claim 6 , wherein the elongate lifting platform and the drive are moved in opposite axial directions in a further portion of the second stroke.   The inserter according to claim 1, wherein the actuator includes a pair of hand grips, one grip is fixed to the frame so as not to move, and the other grip is pivotally connected to the frame. The inserter of claim 1 , further comprising an indicator movably coupled to the lifting platform to provide a visual indication of the position of the lifting platform. An inserter for dilating an expandable spinal interbody fusion device and inserting an insert therein
An actuator comprising a frame and an operating mechanism;
An elongate cartridge releasably connected to the frame, the cartridge movably supporting an elongate elevating platform for dilating the expandable intervertebral body fusion device and at least partially from the elevating platform; An elongate track supporting an elongate drive for inserting an insert into the expandable interbody fusion device, and a plurality of linearly arranged inserts, so as to move independently independently An elongate cartridge disposed on the frame such that the lift platform and the drive are operably connected to the operating mechanism separately;
An inserter comprising: The inserter according to claim 10 , wherein the cartridge is disposable. The inserter according to claim 11 , wherein the actuator is reusable. The inserter of claim 10 , wherein the frame of the actuator comprises a flexible latch for releasably connecting to the cartridge. 14. The inserter according to claim 13 , wherein the frame comprises a movable lever for actuating the flexible latch and releasing the cartridge from the frame. The actuator includes a pair of hand grips, one grip is fixed to the frame so as not to move, the other grip is pivotally connected to the frame, and is spring-loaded with respect to the one grip. The inserter according to claim 10 .

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