초록 ▼

An artificial interbody spinal implant adapted for placement across an intervertebral space formed across the height of a disc space between two adjacent vertebral bodies is disclosed. The implant has an asymmetrical leading end adapted to sit upon the more peripheral areas, such as the apophyseal r

An artificial interbody spinal implant adapted for placement across an intervertebral space formed across the height of a disc space between two adjacent vertebral bodies is disclosed. The implant has an asymmetrical leading end adapted to sit upon the more peripheral areas, such as the apophyseal rim and the apophyseal rim area, of the vertebral end plate region of the vertebral bodies without protruding therefrom. The asymmetrical leading end allows for the safe use of an implant of maximum length for the implantation space into which it is installed. The implant can also include an asymmetric trailing end adapted to sit upon the more peripheral areas of the vertebral end plate region of the vertebral bodies.

대표청구항 ▼

1. An artificial interbody spinal implant for insertion at least in part across the surgically corrected height of a disc space between adjacent vertebral bodies of a human spine, the vertebral bodies having an anterior aspect and a posterior aspect, said implant having a structure comprising: a lea

1. An artificial interbody spinal implant for insertion at least in part across the surgically corrected height of a disc space between adjacent vertebral bodies of a human spine, the vertebral bodies having an anterior aspect and a posterior aspect, said implant having a structure comprising: a leading end for insertion first into the disc space, a trailing end opposite said leading end, and therebetween a length along a mid-longitudinal axis of said implant, said leading end being asymmetrical;opposed portions between said leading and trailing ends adapted to be placed within the disc space to contact and support the adjacent vertebral bodies, said opposed portions being non-arcuate along at least a portion of the length of said implant, said opposed portions having at least one opening therein, said structure being formed at least in part of a base material other than bone, said material comprising at least one of surgical quality titanium and its alloys, cobalt chrome alloy, tantalum, any metal or alloy suitable for the intended purpose, any ceramic material suitable for the intended purpose, and any plastic or composite material suitable for the intended purpose, said openings being in communication with one another to permit for the growth of bone from adjacent vertebral body to adjacent vertebral body through said implant;an interior facing side wall, an exterior facing side wall opposite said interior side wall, and a width therebetween, said width of said implant being less than approximately one-half of the maximum width of the adjacent vertebral bodies into which said implant is adapted to be inserted, said interior and exterior side walls extending between said opposed portions and said leading and trailing ends, said interior side wall adapted to be oriented toward another implant when inserted within the disc space, said exterior facing side wall including a straight portion along the length of said implant, said trailing end being curved across a majority of the width of said implant;a first distance as measured along the mid-longitudinal axis of said implant from an intersection of said leading end and the mid-longitudinal axis of said implant to an intersection of the mid-longitudinal axis of said implant and a plane perpendicular to and bisecting the length along the mid-longitudinal axis of said implant, said first distance being greater than a second distance as measured along the mid-longitudinal axis of said implant from an intersection of said perpendicular plane and said exterior side wall to a junction of said leading end and said exterior side wall; anda third distance as measured along the mid-longitudinal axis of said implant from a junction of said leading end and said interior side wall to an intersection of said interior side wall and said perpendicular plane, said third distance being greater than said second distance, said first distance being greater than said third distance, said leading end including a curved portion extending from the junction of said leading end and said exterior side wall to at least the intersection of said leading end and the mid-longitudinal axis of said implant. 2. The implant of claim 1, wherein said leading end is at least in part non-linear. 3. The implant of claim 1, wherein more than half of said leading end is a curve that extends from said exterior side wall toward the mid-longitudinal axis of said implant in a plane dividing said implant into an upper half and a lower half. 4. The implant of claim 1, wherein said leading end includes a curve that extends from said exterior side wall beyond the mid-longitudinal axis of said implant. 5. The implant of claim 1, further comprising a plurality of surface roughenings for engaging the adjacent vertebral bodies and for maintaining said implant in place, said surface roughenings being present on at least a part of said opposed portions. 6. The implant of claim 1, in combination with a fusion promoting material other than bone. 7. The implant of claim 1, wherein at least a portion of said implant is bioresorbable. 8. The implant of claim 1, further in combination with bone morphogenetic protein. 9. The implant of claim 1, further in combination with an osteogenic material. 10. The implant of claim 1, further comprising a plurality of openings and passages for retaining fusion promoting substance. 11. The implant of claim 1, wherein said leading and trailing ends each have a radius of curvature, the radius of curvature of said leading end being different from the radius of curvature of said trailing end. 12. An artificial interbody spinal implant for insertion at least in part across the surgically corrected height of a disc space between adjacent vertebral bodies of a human spine, the vertebral bodies each having an anterior aspect, a posterior aspect, and an endplate having an apophyseal rim proximate the perimeter of the endplate, said implant having a structure comprising: a leading end for insertion first into the disc space, a trailing end opposite said leading end, and therebetween a length along a mid-longitudinal axis of said implant, said leading end being asymmetrical;opposed portions between said leading and trailing ends adapted to be placed within the disc space to contact and support the adjacent vertebral bodies, said opposed portions being non-arcuate along at least a portion of the length of said implant, each of said opposed portions having at least one opening therein to permit for the growth of bone from adjacent vertebral body to adjacent vertebral body through said implant, said structure being formed at least in part of a base material other than bone, said material comprising at least one of surgical quality titanium and its alloys, cobalt chrome alloy, tantalum, any metal or alloy suitable for the intended purpose, any ceramic material suitable for the intended purpose, and any plastic or composite material suitable for the intended purpose;an interior facing side wall, an exterior facing side wall opposite said interior side wall, and a width therebetween, said width of said implant being less than approximately one-half of the maximum width of the adjacent vertebral bodies into which said implant is adapted to be inserted, said interior and exterior side walls extending between said opposed portions and said leading and trailing ends, said trailing end being curved across a majority of the width of said implant, said leading end including a curved portion extending from a junction of said leading end and said exterior side wall to at least the intersection of said leading end and the mid-longitudinal axis of said implant, said interior facing side wall adapted to be oriented toward another implant when inserted within the disc space, each of said opposed portions having a vertebral body contacting surface between said at least one opening and at least one of said interior facing side wall and said exterior side wall, each of said vertebral body contacting surfaces being adapted to be placed toward one of the adjacent vertebral bodies, said vertebral body contacting portions being at least in part between said interior facing side wall and said exterior side wall, said opposed portions being spaced apart to define a hollow interior in communication with said openings, said exterior facing side wall including a straight portion along the length of said implant;a first distance as measured along the mid-longitudinal axis of said implant from an intersection of said leading end and the mid-longitudinal axis of said implant to an intersection of the mid-longitudinal axis of said implant and a plane perpendicular to and bisecting the length along the mid-longitudinal axis of said implant, said first distance being greater than a second distance as measured along the mid-longitudinal axis of said implant from an intersection of said perpendicular plane and said exterior side wall to the junction of said leading end and said exterior side wall;a third distance as measured along the mid-longitudinal axis of said implant from a junction of said leading end and said interior side wall to an intersection of said interior side wall and said perpendicular plane, said third distance being greater than said second distance, said first distance being greater than said third distance; andsaid implant having a minimum length as measured from said leading end to said trailing end so that said leading end and said trailing end of said implant are adapted to rest upon portions of the apophyseal rim when implanted, said implant being adapted to be wholly contained within the disc space when implanted. 13. The implant of claim 12, wherein said leading end includes a curve that extends from said exterior facing side wall beyond the mid-longitudinal axis of said implant. 14. The implant of claim 12, further comprising at least one protrusion extending from at least one of said opposed portions for engaging at least one of the adjacent vertebral bodies to maintain said implant within the disc space. 15. The implant of claim 12, further comprising a plurality of surface roughenings for engaging the adjacent vertebral bodies and for maintaining said implant in place, said surface roughenings being present on at least a part of said opposed portions. 16. The implant of claim 12, in combination with a fusion promoting substance. 17. The combination of claim 16, wherein said fusion promoting substance is at least one of bone morphogenetic protein and hydroxyapatite. 18. The implant of claim 12, wherein at least a portion of said implant is bioresorbable. 19. The implant of claim 12, wherein at least a portion of said opposed portions are in a diverging relationship to each other from trailing end to leading end for allowing angulation of the adjacent vertebral bodies relative to each other. 20. The implant of claim 12, wherein said leading and trailing ends each have a radius of curvature, the radius of curvature of said leading end being different from the radius of curvature of said trailing end.