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 an implant substrate comprising at least one insert cavity and bone securing serrations, and at least one insert component. The at least one insert component and is configured to be securely coupled to the implant substrate via entry of the at least one insert component into the at least one insert cavity via a lateral sidewall thereby forming the spinal implant. The insert component is internally positioned inside the implant substrate when securely coupled to the implant substrate. The at least one insert cavity and the at least one insert component are securely coupled via a mechanical interlock configuration. In an alternative aspect, the spinal implant comprises one insert component configured to be securely coupled to the implant substrate via a first or second insert cavity to thereby form the spinal implant. In such an embodiment, the one insert component, when securely coupled to the implant substrate, laterally spans across the implant substrate between a first and second lateral sidewall. In a preferred aspect, the implant substrate is comprised of a radiopaque titanium (Ti) or metallic material and the at least one insert component is a polyetheretherketone (PEEK) or resorbable material. Additionally, the implant substrate may be coated with a Hydroxyapatite (HA) layer.
The present application also discloses a spinal implant for insertion into and positioning in an intervertebral disc space. The implant comprises an implant substrate comprising at least one insert cavity and bone securing serrations, and at least one insert component configured to be positioned inside the at least one insert cavity. The at least one insert component is configured to be securely coupled to the implant substrate via a lateral sidewall entry into the at least one insert cavity to thereby form the spinal implant. The at least one insert cavity and the at least one insert component are securely coupled via a mechanical interlock configuration. In another aspect, the spinal implant comprises one insert component configured to be securely coupled to the implant substrate via a first or second insert cavity to thereby form the spinal implant. In such an embodiment, the one insert component, when securely coupled to the implant substrate, laterally spans across the implant substrate between a first and second lateral sidewall. In a preferred aspect, the implant substrate is comprised of a radiopaque titanium (Ti) or metallic material and the at least one insert component is a polyetheretherketone (PEEK) or resorbable material. Additionally, the implant substrate may be coated with a Hydroxyapatite (HA) layer.
There is further provided a spinal implant for insertion into an intervertebral disc space for intervertebral stabilization, the implant comprising a radiolucent polymer substrate coupled to a radiopaque and osseoconductive bone securing component
There is further provided a spinal implant for insertion into an intervertebral disc space for intervertebral stabilization. The implant comprises a radiopaque implant substrate having bone securing serrations coupled to a radiolucent insert which provides the spinal implant with secure fixation within the intervertebral disc space and adjacent vertebrae. The disclosed spinal implant includes radiolucent, radiopaque and osseointegrative properties that facilitate radiographic assessment of fusion across the disc space, assessment of osseointegration between vertebral endplates and osseointegration of the spinal implant to adjacent vertebral end plates.
The present application also discloses a biocompatible spinal implant for insertion into an intervertebral space between adjacent vertebral members. The implant imparts, distracts and restores desired disc space height in adjacent vertebral bodies when the implant is positioned in the intervertebral disc space and enables fusion of the adjacent vertebrae. The implant comprises a radiopaque metallic implant substrate having bone securing serrations coupled to a radiolucent polyetheretherketone (PEEK) insert component which enable the spinal implant to be securely positioned in the intervertebral disc space between adjacent vertebral endplates. In a preferred aspect, the implant substrate is preferably a titanium (Ti) material or a titanium (Ti) alloy.
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 a spinal implant with a metallic implant substrate coupled to a polymer insert component where the implant substrate includes surface serrations, teeth, texture or extensions which enable the spinal implant to be securely positioned between adjacent vertebral endplates. The 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 spinal implant includes radiolucent, radiopaque and osseointegrative properties that facilitate radiographic assessment of fusion or the bridging bone mass across the disc space while reducing stress shielding effects, radiographic assessment of osseointegration between vertebral endplates and implant surfaces, and osseointegration of the spinal implant to adjacent vertebral bodies. 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.
In the preferred aspect shown in
In a preferred aspect, the spinal implant 10 comprises a substrate 20 and a pair of insert components 50 and 51. The substrate 20 comprises a leading end 22 which has a substantially curved or rounded surface to permit the implant body 10 to distract collapsed or semi-collapsed adjacent vertebral bodies 100 and 105 when the implant 10 is introduced or inserted into a disc space 101. The implant 10 also includes a rear end 24 with a recess section 26 and orifice 28 extending inwardly in a direction from a rear end wall 29 toward the implant's leading end 22. The recess section 26 and orifice 28 provide a means to attach an instrument (not show) to grasp, attach to and manipulate the insertion and orientation of the spinal implant 10 as the implant 10 is delivered to a selected or desired disc space 101.
The spinal implant substrate 20 further comprises first and second lateral sections or sidewalls 40 and 41 between the leading end 22 and rear end 24. In the preferred embodiment, there is a first insert cavity 30 substantially centered in the first lateral sidewall 40 configured to accept a complimentarily configured insert component 50, and partially extends into the implant's leading and rear ends 22 and 24. The first insert cavity 30 is defined and positioned between the upper and lower portions of the first lateral sidewall 40 and the substrate's leading end 22 and rear end 24. Additionally, there is a corresponding or opposing second insert cavity 31 substantially centered in the second lateral sidewall 41 and partially extends into the implant's leading and rear ends 22 and 24. The second insert cavity is also configured to accept a complimentarily configured insert component 51. The second insert cavity 31 is defined and positioned between the upper and lower portions of the second lateral sidewall 41 and the substrate's leading end 22 and rear end 24. Those of skill in the art will readily recognize that the insert cavity 30 or 31 may have a configuration where the insert cavity 30 or 31 only minimally or does not extend into the implant's leading and rear ends 22 and 24 or only minimally extends into the into the implant's leading and rear ends 22 and 24 such that the insert cavity 30 or 31 is substantially or entirely positioned in a lateral sidewall 40 or 41. For example as shown in
The insert cavities 30 and 31 will facilitate the placement of the insert components 50 and 51 into the implant substrate 20 by permitting sliding entry of the insert components 50 and 51 therein. The insert cavities 30 and 31 and the insert components 50 and 51 preferably have complimentary and corresponding configurations such that the implant substrate 20 and insert components 50 and 51 can be lockingly engaged when the insert components 50 and 51 are slideably coupled or combined with the implant substrate 20. Those of skill in the art will recognize that the insert component 50 and 51 and corresponding insert cavities 30 and 31 can have a variety of complimentary and cooperating configurations which permit the insertion of the insert components 50 and 51 into the implant substrate 20. The locking or secure engagement between the insert components 50 and 51 and the implant substrate insert cavities 30 and 31 can be a result from the complimentary and corresponding configurations of the insert components 50 and 51 and insert cavities 30 and 31. This mechanical coupling or locking engagement is or can be a friction fit or interference fit. Those of skill in the art will recognize that other locking or engagement mechanisms may be use to securely couple the insert components 50 and 51 to the implant substrate 20, for example a rough or uneven surface interface between the insert components 50 and 51 and insert cavities 30 and 31 to increase the friction fit strength. Other attachment means contemplated to securely couple the insert components 50 and 51 to the implant substrate 20 include pins, rivets, screws, bolts and nuts, adhesive bonding, thermal bonding, dove tail, mechanical interlocking, over-molding, insert molding, or combinations thereof.
In the preferred embodiment, the spinal implant substrate 20 further comprises insert securing tenons 21, 23, 25 and 27 which cooperate with corresponding insert component channels 52, 53, 55 and 57 to augment the locking or engagement between the insert components 50 and 51 to the implant substrate 20, when the insert components 50 and 51 are inserted into the insert cavities 30 and 31. The first and second insert securing tenons or extensions 21 and 23 extend inwardly into the insert cavities 30 and 31 away from the interior of the substrate's leading end 22, best shown in
As the insert components 50 and 51 are inserted into the insert cavities 30 and 31, the securing tenons 21, 23, 25 and 27 and insert component channels 52, 53, 55 and 57 travel towards each other until the securing tenons 21, 23, 25 and 27 are positioned inside the insert component channels 52, 53, 55 and 57. At this point, the insert components 50 and 51 are securely coupled to the implant substrate 20. The combined securing tenons 21, 23, 25 and 27 and insert component channels 52, 53, 55 and 57, which are now securely engaged and mechanically interlocked, augment or supplement the friction fit or interference fit between the implant substrate 20 and insert components 50 and 51. This augmented mechanical coupling or locking engagement comprises both a friction fit or interference fit and mechanical interlock between the implant substrate 20 and insert components 50 and 51. Those of skill in the art will recognize that the insert securing tenons 21, 23, 25 and 27 and insert component channels 52, 53, 55 and 57 can have a variety of complimentary configuration which can secure and lockingly engage the insert components 50 and 51 to the implant substrate 20.
In the preferred aspect shown in
The spinal implant substrate 20 also comprises an upper implant surface 60 defined by the upper portions of the leading end 22, rear end 24, first lateral sidewall 40 and second lateral sidewall 41, and a lower implant surface 61 defined by the lower portions of the leading end 22, rear end 24, first lateral sidewall 40 and second lateral sidewall 41. The upper implant surface 60 comprises an implant substrate aperture 62 defined by the upper portions or sections of the substrate's leading end 22, rear end 24 and first and second lateral sidewalls 40 and 41. The lower implant surface 61 comprises an opposing implant substrate aperture 62 defined by the lower portions or sections of the substrate's leading end 22, rear end 24 and first and second lateral sidewalls 40 and 41. The implant's 10 substrate aperture 62 is configured such that that there is a substantially vertical channel or cavity that extends between and through the upper and lower implant surfaces 60 and 61. Additionally, the substantially vertical implant channel 62, in conjunction with the first and second insert cavities 30 and 31, define a substantially lateral or horizontal cavity that extends laterally across and through the implant substrate 20 between the implant's first and second later sidewalls 40 and 41. This will permit insertion of one or more insert components 50, 51, 150, 151 or 250 into the implant substrate 20, 120 or 220.
In a preferred embodiment, the implant substrate apertures 62 permit the insertion of a graft material which assists in promoting fusion 100 and 105 of the adjacent vertebrae 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, a demineralized bone matrix putty or gel and/or any combination thereof. The graft filler material may promote bone growth through and around the substrate aperture 62 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 implant substrate 20 further comprises upper and lower bone securing surface serrations, teeth, projections or extensions 70 which enable the spinal implant 10 to be securely positioned between adjacent vertebral endplates and act as anti-ejection aspects for the coupled implant 10. The surface serrations 70 preferably extend outwardly from the upper and lower implant surfaces 60 and 61. In the upper implant surface 60, the surface serrations 70 are preferably configured and positioned on the upper portions or sections of the first and second lateral sidewalls 40 and 41, between the substrate's leading end 22 and rear end 24. And, in the lower implant surface 61, the surface serrations 70 are preferably configured and positioned on the opposing lower portions or sections of the first and second lateral sidewalls 40 and 41, between the substrate's leading end 22 and rear end 24.
The implant serrations 70 directly interact with and engage the vertebral endplates 103 and 109 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 70 are preferably oriented in a rear lean direction such that the teeth or serrations 70 are oriented away or opposite the implant leading end 22 and toward the implant rear end 24. In this manner, the rear leaning orientation of the teeth or serrations 70 provide minimal resistance when the spinal implant is being inserted into a disc space 101. Once inserted, the rear leaning orientation of the teeth or serrations 70 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
In the preferred aspect shown in
In the preferred aspect shown in
The leading insert end 81, rear insert end 86 and central insert section 83 are configured such that they define an insert component 50 or 51 that has a configuration or shape that is complimentary to a corresponding implant substrate cavity 30 or 31, as shown in
The opposing rear insert end 86 includes a substantially flat engaging surface 86A which comprises insert component channels 55 and 57 which will engage corresponding rear end securing tenons 25 and 27 when the insert 50 or 51 is inserted into the implant insert cavity 30 or 31. The rear insert end 86 will also have a thickness between exterior and interior leading rear end surfaces 86B and 86C. In this embodiment, the rear insert end's 86 thickness between its interior and exterior surfaces 86B and 86C is such that the rear insert end 86 extends into the insert cavity 30 or 31 to about a point substantially midway along the interior facing surface 87 of the substrate's rear end 24. Those of skill in the art will recognize that the rear insert end's 86 thickness between interior or exterior leading insert end 86B and 86C may vary as may be needed or desired by a physician, procedure or medical application. For example,
The central insert section 83 will have a thickness between exterior and interior central insert section surfaces 83B and 83C. In this preferred aspect, the central insert section surface 83C, the leading insert end interior surface 81C and the rear insert end interior surface 86C together form a continuous interior insert surface for the insert components 50 and 51 which will define the implant substrate aperture 62. The central insert section 83 also includes an insert aperture 83A that extends between and through the exterior and interior central insert section surfaces 83B and 83C. The insert aperture 83A is a cylindrical aperture but may have other configurations as may be needed or desired by a physician, procedure or medical application. In this embodiment, the central insert section's 83 thickness between its interior and exterior surfaces 83B and 83C is substantially the same as the thickness of the lateral side walls 40 or 41. Those of skill in the art will recognize that the central insert sections' 83 thickness between interior or exterior leading insert end 83B and 83C may vary as may be needed or desired by a physician, procedure or medical application. For example,
In the preferred aspect, shown in
The implant body or substrate 120 comprises a leading end 122, a rear end 124, and first and second lateral section sidewalls 140 and 141 between the leading end 122 and a rear end 124. The first insert cavity 130 is defined and positioned between the upper and lower portions of the first lateral sidewall 140 and the substrate's leading end 122 and rear end 124. The first cavity 130 has a configuration that is complimentary to the first insert component 150 which permits the first cavity 130 to accept the complimentarily configured insert component 150 therein. An opposing second insert cavity 131 is defined and positioned between the upper and lower portions of the second lateral sidewall 141 and the substrate's leading end 122 and rear end 124. The second insert cavity 131 has a configuration that is complimentary to the second insert component 151 which permits the second cavity 131 to accept the complimentarily configured insert component 151 therein.
The first insert cavity 230 is defined and positioned between the upper and lower portions of the first lateral sidewall 240 and the substrate's leading end 222 and rear end 224. An opposing second insert cavity 231 is defined and positioned between the upper and lower portions of the second lateral sidewall 241 and the substrate's leading end 222 and rear end 224. The first and second cavities 230 and 231 will have configurations that are complimentary to the single insert component 250 size and configuration which thereby permits the insert cavity 230 or 231 to accept the complimentarily configured insert component 250 therein. In this aspect, the insert component 250 is a single body 255 that will be inserted and positioned in the implant substrate 220 and which will laterally span across the implant 210 and the insert cavities 230 and 231 between the first and second lateral side walls 240 and 241, as shown in
In a preferred spinal implant embodiment 10, 110 or 210, the implant substrate 20, 120 and 220 is preferably a titanium (Ti) material which is radiopaque and osseoconductive biomaterial, and the opposing insert components 50, 51, 150, 151 and 250 are preferably polyetheretherketone (PEEK) polymer materials which are radiolucent biomaterials with a lower modulus of elasticity. As discussed above, the implant substrate's 20, 120 and 220 titanium serrations or teeth provide an exterior bone-contacting surface which enables immediate and strong fixation of the implant 10, 110 and 210 to adjacent vertebrae in the disc space. The implant substrate's 20, 120 and 220 titanium serrations or teeth also assist in long-term osseointegration for the device while allowing for radiographic assessment of osseointegration between endplates 103 and 107 and implant's 10, 110 and 210 surfaces. The radiolucent PEEK insert components 50, 51, 150, 151 and 250 allows for radiographic assessment of fusion or bridging bone mass across the disc space while reducing stress-shielding effects. These are advantageous characteristics and properties that are contemplated for the implant embodiments 10, 110, 210 disclosed herein which couple an osseoconductive radiopaque implant substrate 20, 120 and 220 with one or more radiolucent insert components 50, 51, 150, 151 and 250.
In a preferred aspect, where the implant substrate 20, 120 and 220 is titanium and the insert components 50, 51, 150, 151 and 250are PEEK material, the titanium implant substrate 20, 120 and 220, which is a single piece or component, will carry the load or take on compressive force that is exerted on the implant 10, 110 and 210 in the disc space 101. Further, due to the configuration and positioning of the PEEK insert components 50, 51, 150, 151 & 250 inside the substrate insert cavities 30, 31, 130, 131, 230 and 231, the PEEK insert components 50, 51, 150, 151 and 250 will act as a support strut and take or and support compressive load between the implant 10, 110 and 210 upper and lower substrate surfaces. This aspect leads to an advantageous characteristic that there is load sharing between the between titanium implant substrate 20, 120 and 220 and PEEK insert components 50, 51, 150, 151 and 250.
The embodiments of
In the disclosed embodiments, the volume of interior implant substrate 220 taken up by the one or more insert components 50, 51, 150, 151 and 250 will vary depending on spinal implant 10, 110 or 210 used. As shown in
In the preferred aspect, where the implant substrate 20, 120 and 220 is a Ti material and the insert component 50, 51, 150, 151 and 250 is a PEEK polymer material, as the size, mass or volume of the insert component 50, 51, 150, 151 and 250 increases from smaller (second embodiment 120) to larger (third embodiment 220) there results a larger mass or volume of PEEK insert component material 50, 51, 150, 151 and 250 compared to the Ti implant substrate 20, 120 and 220 mass or volume which is decreasing as the mass of PEEK insert component 50, 51, 150, 151 and 250 increases, where the exterior size of the implant substrate does not change. Thus, the ratio of the materials making up the implant 10, 110 and 210 would be more PEEK insert component polymer material 50, 51, 150, 151 and 250 than Ti implant substrate material 20, 120 and 220. This aspect results in an advantageous implant characteristic such that, from an imaging standpoint, the spinal implant 10, 110 and 210 would have more radiolucent insert component material 50, 51, 150, 151 and 250 and thus greater resultant spinal implant 10, 110 and 210 radiolucent properties. Additionally, when there is more PEEK insert component material 50, 51, 150, 151 and 250, the spinal implant's 10, 110 and 210 overall compressive modulus or stiffness is less as compared to when there is more titanium implant substrate material 20, 120 and 220. Lower overall compressive modulus/stiffness for the spinal implant 10, 110 and 210 is an advantageous aspect since such an implant 10, 110 and 210 more closely approximates the modulus of the bone. Those of skill in the art will thus recognize that the size of the PEEK insert component 50, 51, 150, 151 and 250 can be increase to improve overall implant 10, 110 and 210 compressive stiffness, such that one could transition from less PEEK insert mass (the smaller two insert piece second embodiment 120) to a single large PEEK insert mass (the larger single insert piece third embodiment 220) which would then have better overall implant compressive stiffness characteristic and radiolucent properties. The size, mass and volume of the PEEK insert component 50, 51, 150, 151 and 250 and corresponding complimentary implant substrate 20, 120 and 220 size, mass and volume can be selected for a particular spinal implant as may be desired or required by a surgeon or medical procedure or application.
In the disclosed embodiments of
The spinal implants 10, 110 and 210 disclosed in this disclosure are preferably comprised of a biocompatible osseoconductive radiopaque implant substrate with one or more attachable or insertable biocompatible radiolucent insert components which are configured and adapted for insertion into and positioning in an intervertebral disc space so as to contact against adjacent vertebral members. The implant substrate 20, 120 and 220 includes serrations or teeth 70, 170 and 270 which provide or promote fixation as well as long-term osseointegration for the implant device 10, 110 and 210 while allowing assessment of osseointegration between vertebral endplates and spinal implant surfaces. Fusion and osseointegration can be improved and accelerated through the use and application of a Hydroxyapatite or HA coating on the spinal implant surfaces and substrate serrations or teeth 70, 170 and 270. The biocompatible insert component 50, 51, 150, 151 and 250 is preferably a polyetheretherketone (PEEK) polymer material. The spinal implant 10 and 200 contemplated herein allows radiographic assessment of fusion and the bridging bone mass across the disc space while reducing stress-shielding effects.
The biocompatible insert component 50, 51, 150, 151 and 250 is preferably a radiolucent biocompatible materials such as PEEK and carbon fiber reinforced PEEK, etc., however, those of skill in the art will recognize that other insert component material may also be used, including among others, 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 insert component 50, 51, 150, 151 or 250 may also be a resorbable polymer material. The resorbable polymer, includes, but not limited to, polylactide, polyglycolide, copolymers of polylactide and polyglycolide, polycaprolactone, polyorthoester, tyrosine-polycarbonate, polurethane, etc. In the case where the insert component 50, 51, 150, 151 and 250 is a restorable material, the insert components 50, 51, 150, 151 and 250 is resorbed over a period of time such that the restorable insert component 50, 51, 150, 151 and 250 is gradually resorbed away as fusion within the disc space 101 progresses and the resorbable insert components 50, 51, 150, 151 and 250 is not needed anymore. As the resorbable insert component 50, 51, 150, 151 and 250 is resorbed there is left a void or cavity where the insert component 50, 51, 150, 151 and 250 existed before it was resorbed, and bone can grow into the void or cavity.
The biocompatible radiopaque and osseoconductive implant substrate 20, 120 and 220 is preferably a Titanium (Ti) or metallic material. However, those of skill in the art will recognize that other metallic materials may also be used, including, among others, stainless steel, titanium alloys, nitinol, platinum, tungsten, silver, palladium, gold, cobalt chrome alloys, shape memory nitinol and mixtures thereof. Additionally, the metallic material may have a porosity aspect in order to improve fixation of the implant. The bone-contacting surfaces, serrations or teeth of the implant substrate's metallic material 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 pore size diameter 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 porosity 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. Further, the biocompatible substrate 20, 120 and 200 and insert components 50, 51, 150, 151 and 250 used may depend on the patient's need and physician requirements. The spinal implant substrate 20, 120 and 220 and insert components 50, 51, 150, 151 and 250 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 posterior (PLIF) 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 implant 10, 110 or 210 is prepared in the disc space 101. Those of skill in the art will recognize that the 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 implant 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 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 implant 10, 110 or 210 into the vertebral disc space 101 and through the surrounding patient anatomical environment.
The 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 70, 170 and 270 are positioned between and adjacent to the upper and lower vertebral endplates 103 and 107. The substrate serrations 70, 170 and 270 may engage the vertebral endplates 103 and 107 to provide stability to the implant 10, 110 or 210. Once implanted, the implant's upper surface serrations or teeth 70, 170 and 270 will contact the upper vertebral end plate 103 to form an interface between the implant 10, 110 or 210 and the upper vertebral body 100. Also, the implant's lower surface serrations or teeth 70, 170 and 270 will contact the lower vertebral end plate 107 to form an interface between the implant 10, 110 or 210 and the lower vertebral body 105. After the insertion 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.