The present application is directed to implants, devices and methods for stabilizing vertebral members, and more particularly, to intervertebral implants, devices and methods of use in replacing, in whole or in part, an intervertebral disc, a vertebral member, or a combination of both to distract and/or stabilize the spine.
The spine is divided into four regions comprising the cervical, thoracic, lumbar, and sacrococcygeal regions. The cervical region includes the top seven vertebral members identified as C1-C7. The thoracic region includes the next twelve vertebral members identified as T1-T12. The lumbar region includes five vertebral members L1-L5. The sacrococcygeal region includes nine fused vertebral members that form the sacrum and the coccyx. The vertebral members of the spine are aligned in a curved configuration that includes a cervical curve, thoracic curve, and lumbosacral curve. Intervertebral discs are positioned between the vertebral members and permit flexion, extension, lateral bending, and rotation.
Various conditions and ailments may lead to damage of the spine, intervertebral discs and/or the vertebral members. The damage may result from a variety of causes including, but not limited to, events such as trauma, a degenerative condition, a tumor, or infection. Damage to the intervertebral discs and vertebral members can lead to pain, neurological deficit, and/or loss of motion of the spinal elements.
Various procedures include replacing a section of or an entire intervertebral disc, a section of or an entire vertebral member, or both. One or more spinal implants may be inserted to replace damaged discs and/or vertebral members. The implants are configured to be inserted into an intervertebral space and contact against adjacent vertebral members. The implants are intended to reduce or eliminate the pain and neurological deficit, and increase the range of motion.
The curvature of the spine and general shapes of the vertebral members may make it difficult for the implants to adequately contact the adjacent vertebral members or to position the adjacent vertebral members in a desired orientation. There is a need for spinal implants or devices configurable to match the spinal anatomy for secure contact and/or desired orientation of the spinal implants or devices implanted into an intervertebral disc space.
The present application discloses a spinal implant for insertion into and positioning in an intervertebral disc space. The implant comprises a first implant section, an opposing second implant section and at least one expander attached between the first and second implant sections. The at least one implant expander can be selectively expanded to thereby actuate the spinal implant to an expanded position. The at least one implant expander is expanded via injection of an expanding material. The at least one implant expander is selectively expanded to impart substantially vertical expansion, angular expansion or vertical and angular expansion to the spinal implant. The at least one expander can be a balloon that accepts bone cement as the expanding material. The at least one implant expander can impart vertical expansion in the range of between eight and fourteen millimeters (8-14 mm) or an angular expansion in the range of between zero degrees to twelve degrees (0°-12°). The first and second implant sections can be polyetheretherketone (PEEK) or a metallic material such as titanium (Ti).
The present application also discloses a biocompatible expandable spinal implant for insertion into an intervertebral space between adjacent vertebral members. The expandable implant imparts, distracts and restores desired disc space height and angular orientation to adjacent vertebral bodies when the implant is positioned and expanded in the intervertebral disc space and enables fusion of the adjacent vertebrae. The implant comprises a first implant section comprising bone securing serrations, an opposing second implant section comprising bone securing serrations, a first lateral expander attached between the first and second implant sections, and an opposing second lateral expander attached between the first and second implant sections. The first and second lateral expanders can be selectively expanded to actuate the spinal implant to an expanded position. The first and second lateral expanders can be expanded via injection of an expanding material. The first and second lateral expanders can be selectively expanded to impart substantially vertical expansion, angular expansion or vertical and angular expansion to the spinal implant. The first and second lateral expanders can be a balloon that accepts bone cement as the expanding material. The first and second lateral expanders can impart vertical expansion in the range of between eight and fourteen millimeters (8-14 mm) or an angular expansion in the range of between zero degrees to twelve degrees (0°-12°). The first and second lateral expanders can be polyetheretherketone (PEEK) or a metallic material such as titanium (Ti).
The various aspects of the various embodiments may be used alone or in any combination, as is desired. Disclosed aspects or embodiments are discussed and depicted in the attached drawings and the description provided below.
The present disclosure is directed to intervertebral implants for spacing apart vertebral members. The present disclosure relates to medical devices such as spinal intervertebral implants implanted between adjacent vertebral bodies of a spinal column section, and methods of use. More particularly, to an expandable spinal implant with opposing upper and lower implant sections coupled to one or more expandable component or expander such as a bag, balloon, pouch, or sac, where the opposing upper and lower implant sections include surface serrations, teeth, texture or extensions enable the assembled expandable spinal implant to be securely positioned between adjacent vertebral endplates. The expandable implant imparts, distracts and restores desired disc space height in adjacent vertebral bodies when the implant is positioned in the intervertebral disc space. The disclosed expandable spinal implant comprises properties which enable the expandable spinal implant to be expanded vertically to increase the implant's overall height, lordotically to angularly expand the spinal implant or a combination of height and lordotic implant expansion. For purposes of promoting an understanding of the principles of the invention, reference will now be made to one or more embodiments or aspects, examples, drawing illustrations, and specific language will be used to describe the same. It will nevertheless be understood that the various described embodiments or aspects are only exemplary in nature and no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments or aspects, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates.
Additionally, the expandable spinal implant 10 can be selectively controlled to expand such that the expandable spinal implant 10 can be expanded vertically to increase the implant's overall height by expanding the first and second expandable or inflatable components or expanders 40 and 50 by the same amount, as shown in
In the preferred aspect shown in
In a preferred aspect, the expandable spinal implant 10 comprises an upper implant section 20, an opposing lower implant section 30 and opposing first and second expandable components or expanders 40 and 50. The upper implant section 20 comprises an exterior section surface 15 defined by the upper portions of a leading end 12, first lateral sidewall 13 and second lateral sidewall 14, and a rear end 18. The upper implant section 20 further comprises an opposing underside interior section surface 16 defined by the lower portions of the leading end 12, first lateral sidewall 13 and second lateral sidewall 14, and rear end 18. The exterior section surface 15 is partially curved or rounded at the leading end 12 above the substantially flat underside interior section surface 16. The leading end 12, in conjunction with an opposing and complimentary lower implant section 30 leading end 32, facilitates entry or insertion of a collapsed implant body 10 into the disc space 101 to thereafter enable selective or desired distraction of collapsed or semi-collapsed adjacent vertebral bodies 100 and 105. The rear end 18, in conjunction with an opposing and complimentary lower implant section 30 rear leading end 38 and first and second expanders 40 and 50, provide a means to attach one or more insertion instruments (not shown) to grasp, attach to and manipulate the insertion, orientation and expansion of the expandable spinal implant 10 as the implant 10 is delivered to a selected or desired disc space 101.
The upper implant section 20 also comprises an upper aperture 17 defined and bounded by the leading end 12, first lateral sidewall 13, second lateral sidewall 14, and rear end 18. The upper implant section aperture 17 is configured such that it is a substantially vertical channel or cavity that extends between and through the exterior and opposing interior section surfaces 15 and 16. In a preferred aspect, the upper aperture 17 permits the insertion of graft material which assists in promoting fusion of the adjacent vertebrae 100 and 105 at the disc space 101 where the implant 10 is inserted. The graft material may be composed of any type of material that has the ability to promote, enhance and/or accelerate the bone growth and fusion or joining together of the vertebral bodies 100 and 105 by one or more fusion mechanisms such as osteogenesis, osteoconduction and/or osteoinduction. The graft material may include allograft material, bone graft, bone marrow, demineralized bone matrix putty or gel and/or any combination thereof. The graft filler material may promote bone growth through and around the upper aperture 17 to promote fusion of the intervertebral joint 100 and 105. Those of skill in the art will recognize that the use of filler graft material is optional, and it may or may not be used depending on the needs or requirements of a physician or a medical procedure.
The exterior section surface 15 of the implant substrate 20 additionally comprises bone securing surface serrations, teeth, projections or extensions 19 which extend outwardly or away from the exterior section surface 15. The exterior bone securing surface serrations or teeth 19 enable the spinal implant 10 to engage adjacent vertebral endplates 103 and 107 so that the implant 10 can be securely positioned between the adjacent vertebral endplates 103 and 107 and act as an anti-ejection mechanism. In the exterior section surface 15 of the implant substrate 20, the bone securing surface serrations or teeth 19 are preferably configured and positioned on the upper portions or sections of the first and second lateral sidewalls 13 and 14, between the upper implant section's leading end 12 and rear end 18. The implant serrations or teeth 19 directly interact with and engage the vertebral endplates 103 and 107 when the spinal implant 10 is positioned in the disc space 101 and provide, in part, stability of the implant 10 in the disc space 101 between adjacent vertebrae 100 and 105.
In the preferred embodiment, the implant serrations or teeth 19 are preferably oriented in a rear lean direction such that the teeth or serrations 19 are oriented away or opposite the upper implant section's leading end 12 and toward the upper implant section's rear end 18. In this manner, the rear leaning orientation of the teeth or serrations 19 provide minimal resistance when the spinal implant 10 is being inserted into a disc space 101. Once inserted, the rear leaning orientation of the teeth or serrations 19 provide a mechanism to prevent the assembled spinal implant 10 from being ejected, or minimize or retard implant movement in a direction tending to eject the implant 10 from the disc space 101, once the spinal implant 10 is positioned in the disc space 101. In the aspects shown in
The underside interior section surface 16 of the upper implant substrate 20 additionally comprises first and second expander channels 25 and 26, best shown in
The first and second expander channels 25 and 26 will facilitate positioning and secure attachment therein of the respective first and second expandable components or expanders 40 and 50. The secure attachment can be accomplished via a sufficiently and appropriate biocompatible adhesive which will securely bond or attach the first and second expandable components or expanders 40 and 50 to the respective first and second expander channels 25 and 26. In this manner, the upper and lower implant sections 20 and 30 can appropriately translate the force imparted by the expanding first and second expandable components or expanders 40 and 50, as the expandable spinal implant 10 transitioned between a collapsed position, as shown in
With regard to the lower implant section 30, in the disclosed aspect, shown in
The topside interior section surface 36 additionally comprises first and second expander channels 45 and 46, best shown in
In a preferred aspect shown in
In the preferred aspect, the first and second expandable components or expanders 40 and 50 comprise three individual adjacent and attached tube-like expandable parts or segments 41, 42, 43, 51, 52 and 53. The expandable parts or segments 41, 42, 43, 51, 52 and 53 can be an item such as a balloon, bag, pouch, sac, conduit, duct or other item that can selectively expanded. In one aspect, the expandable balloon, bag, pouch, sac, conduit, duct or other item could be comprised of biocompatible material that degrades or can be absorbed over time such that the injected material and by then hardened material remains as a load bearing structure. Although, three expandable parts or segments 41, 42, 43, 51, 52 and 53 are preferred, more or less expandable parts or segments may be used. For example, the first and second expandable components or expanders 40 and 50 could comprise a single expandable part or segment which is coupled or attached between the upper and lower implant sections 20 and 30. Those of skill in the art will recognize that the number of expandable parts or segments 41, 42, 43, 51, 52 and 53 may vary depend on the need or selection of a surgeon or medical procedure or application. The expandable parts or segments 41, 42, 43, 51, 52 and 53 can be securely attached to each other via a sufficiently strong adhesive which will securely bond or attach adjacent expandable parts or segments 41, 42, 43, 51, 52 and 53 to each other and to respective upper and lower first and second expander channels 25, 26, 45 and 46. Those of skill in the art will recognize that other attachments means or mechanisms may be used to securely attach or couple the adjacent expandable parts or segments 41, 42, 43, 51, 52 and 53 to each other and to respective upper and lower first and second expander channels 25, 26, 45 and 46. For example, among others, thermal bonding, a friction fit, an interference fit, a rough or uneven surface interface, mechanical coupling or combinations thereof.
The expandable implant 10 can transition between a collapsed position, shown in
As the expanding material or solution is injected into the parts or segments 41, 42, 43, 51, 52 and 53, the expandable components or expanders 40 and 50 expand, which results in imparting or translating an outward expanding force on the upper and lower implant sections 20 and 30. Continued injection of the material or solution into the parts or segments 41, 42, 43, 51, 52 and 53, and thus continued expansion of the expandable components or expanders 40 and 50, forces the upper and lower implant sections 20 and 30 to continue to expand. As the upper and lower implant sections 20 and 30 continue to expand, they 20 and 30 will in turn impart or translate the outward expanding force to the adjacent vertebral end plates 103 and 107, which will result in expansion of the adjacent vertebrae 100 and 105 and disc space 101. In this manner, the upper and lower implant sections 20 and 30 can appropriately translate the force imparted by the expanding first and second expandable components or expanders 40 and 50, to transition the expandable spinal implant 10 from a collapsed position, as shown in
In this manner, the implant's overall lordotic or angular orientation θ can increase from zero degrees (θ=0°) to a selected or desired lordotic or angular orientation (θ>0°), on a second lateral side with height H4 as shown in
Additionally, those of skill in the art will recognize that that instead of two identical first and second expandable components or expanders 40, 50, 140, 150, 240 and 250, a spinal implant 10, 110, 210 may instead have a single expandable component or expander (not shown) to impart selected or desired height, lordotic or angular expansion, or a combination of height and lordotic or angular expansion as might be needed or required. For example, such an expandable component or expander might have a toroid, ring or other configuration which is complimentarily coupled or attached between the upper and lower implant section 20, 30, 120, 130, 220 and 230. In such a case, the single expandable component or expander would also span the implant 10 between the between the upper and lower implant sections 20 and 30 in order to permit the expandable spinal implant 10 to take on or transition between a collapsed position and an expanded position. Whether one or more expandable components or expanders (not shown) are used with the upper and lower implant section will depend on the selection or requirements of a surgeon or medical procedure or application. Additionally, the expandable spinal implant can comprise an overall shape, configuration or size as may be needed by a surgeon or an implant procedure or application.
In the disclosed embodiments of
The spinal implants 10, 110, 210 upper and lower implant sections 20, 30, 120, 130, 220 and 230 are preferably comprised of a polyetheretherketone (PEEK) polymer material which allows radiographic assessment of fusion and the bridging bone mass across the disc space while reducing stress-shielding effects. While, the biocompatible upper and lower implant sections 20, 30, 120, 130, 220 and 230 are preferably a radiolucent biocompatible materials such as PEEK, those of skill in the art will recognize that other insert component material may also be used, including among others, carbon fiber reinforced PEEK polymer material, homopolymers, co-polymers and oligomers of polyhydroxy acids, polyesters, polyorthoesters, polyanhydrides, polydioxanone, polydioxanediones, polyesteramides, polyaminoacids, polyamides, polycarbonates, polylactide, polyglycolide, tyrosine-derived polycarbonate, polyanhydride, polyorthoester, polyphosphazene, polyethylene, polyester, polyvinyl alcohol, polyacrylonitrile, polyamide, polytetrafluorethylene, poly-paraphenylene terephthalamide, polyetherketoneketone (PEKK); polyaryletherketones (PAEK), cellulose, carbon fiber reinforced composite, and mixtures thereof. The upper and lower implant sections 20, 30, 120, 130, 220 and 230 may also be comprised of a Titanium (Ti) or other metallic material which enable fusion and osseointegration of the implant in the disc space, including, among others, stainless steel, titanium alloys, nitinol, platinum, tungsten, silver, palladium, gold, cobalt chrome alloys, shape memory nitinol and mixtures thereof.
Additionally, the upper and lower implant sections 20, 30, 120, 130, 220 and 230 may have a porosity aspect in order to improve fixation of the implant 10, 110 and 210. The bone-contacting surfaces, serrations or teeth of the implant may have porosity of appropriate or desired sizes and geometry or configuration for optimal and rapid bony in growth. The bone-contacting surfaces, serrations or teeth porosity may have pores that are non-connected or interconnected pores with selected or desired pore size diameters, for example in the range between 1 to 1000 micrometers, preferably between 50 and 250 micrometers. The porosity may have predetermined patterns or have a porosity that has a random geometry or configuration in nature. The upper and lower implant sections 20, 30, 120, 130, 220 and 230 can be further coated or filled with osseoconductive and/or osseoinductive biomaterials such as hydroxyapatite (HA) and human recombinant bone morphogenic protein (rh BMP2). Those of skill in the art will recognize that the pore sizes, pore configuration, pore coating, and/or pore inter-connectivity aspect may be selected or vary for a particular spinal implant 10, 110 or 210 depending on needs or requirements of a physician, procedure or medical application. The spinal implant 10, 11, 210 can be made or manufactured by typical or known techniques and methods know to those of skill in the art, including among others, machining, molding, extrusion, stamping, laser processing, water-jet cutting or combination thereof.
The implant 10, 110 or 210 may be implanted in the disc space 101 using known methods, procedures and approaches, including a posterior (PLIF), direct lateral (DLIF), anterior (ALIF), translateral (TLIF) or any other suitable oblique direction and approach, as those of skill in the art will recognize. Further, a spinal implant may be delivered and inserted through known surgical technique and procedures, including: open, mini-open, minimal access spinal technologies (MAST) or other minimally invasive surgical (MIS) techniques.
In one approach, the implant 10, 110 or 210 is inserted via a direct lateral (DLIF) approach, for example as shown in
Prior to insertion, known medical instruments and tools may be used to prepare the intervertebral disc space 101, including pituitary rongeurs and curettes for reaching the nucleus pulposus or other area in the disc space 101. The disc space 101 may be prepared with a partial or complete discectomy. Ring curettes may be used as necessary to scrape abrasions from the vertebral endplates 103 and 107. Using such instruments, a location which will accept the collapsed implant 10, 110 or 210 is prepared in the disc space 101. Those of skill in the art will recognize that the collapsed implant 10, 110 or 210 may be positioned at any desired location between the adjacent vertebral bodies 103 and 107 depending on the surgeon's need and the performed surgical procedure or medical application.
The collapsed implant 10, 110, 210 is then inserted into the prepared disc space 101 using insertion instruments which are appropriate with the shape and configuration of the implant and surgical procedure to be used. A medical imaging technique and device may be used to visualize the implant 10, 110 or 210 during the insertion procedure by taking advantage of the implant's radiolucent and/or radiopaque properties. During the insertion step, the enhanced implant visualization will permit the surgeon to better maneuver and control the trajectory, position and orientation of the collapsed implant 10, 110 or 210 into the vertebral disc space 101 and through the surrounding patient anatomical environment.
The collapsed implant 10, 110 or 210 is then delivered into the intervertebral disc space 101 and positioned in a selected location and orientation between the end plates 103 and 107 of the adjacent vertebral bodies 100 and 105. The implant is inserted into the disc space 101 such that the implant upper and lower surface serrations or teeth are positioned between and adjacent to the upper and lower vertebral endplates 103 and 107. The implant's serrations may engage the vertebral endplates 103 and 107 to provide stability to the implant 10, 110 or 210. Once implanted, the implant is selectably and controbably expanded such that the implant's surface serrations or teeth will contact the upper and lower vertebral end plates 103 and 107 to form an interface between the implant 10, 110 or 210 and the adjacent vertebral bodies 100 and 105. The expanded implant will impart selected or desired height, lordotic or angular expansion, or a combination of height and lordotic or angular expansion. After the insertion and expansion of the implant 10, 110 or 210 between the vertebral bodies 100 and 105 has been completed, the implant graft material will promote the fusion or joining together of the vertebral bodies 100 and 105.
Spatially relative terms such as “under”, “below”, “lower”, “over”, “upper”, and the like, are used for ease of description to explain the positioning of one element relative to a second element. These terms are intended to encompass different orientations of the device in addition to different orientations than those depicted in the figures. Further, terms such as “first”, “second”, and the like, are also used to describe various elements, regions, sections, etc and are also not intended to be limiting. Like terms refer to like elements throughout the description.
As used herein, the terms “having”, “containing”, “including”, “comprising” and the like are open ended terms that indicate the presence of stated elements or features, but do not preclude additional elements or features. The articles “a”, “an” and “the” are intended to include the plural as well as the singular, unless the context clearly indicates otherwise.
While embodiments of the invention have been illustrated and described in detail in the present disclosure, the disclosure is to be considered as illustrative and not restrictive in character.
While embodiments of the invention have been illustrated and described in the present disclosure, the disclosure is to be considered as illustrative and not restrictive in character. The present invention may be carried out in other specific ways than those herein set forth without departing from the scope and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes and modifications that come within the spirit of the invention are desired to be protected and are to be considered within the scope of the disclosure. Further, all changes coming within the meaning and equivalency range of the appended claims are also intended to be embraced therein.