Minimally Invasive Interbody Device

Abstract

An interbody device that restores the disc space height between two vertebrae during spinal fusion surgery. The device includes a center plate surrounded by a perimeter portion that combine to have a relatively flat configuration in one dimension and relatively wide configuration in a perpendicular dimension. After the disc space has been cleared, the device is inserted into the disc space in a direction so that the wide dimension of the device is substantially parallel to the body of the vertebrae. The device is then rotated so that the wide dimension of the device becomes perpendicular to the vertebral body so as to cause the disc space height to be restored. Bone graft material is then introduced through a fill tube coupled to the device so that the bone graft material is distributed on both sides of the center plate and into the disc space.

1 - 20 . (canceled) 
     
     
         21 . An interbody device for restoring the disc space height of the disc space between opposing vertebral bodies of adjacent vertebrae during a spinal fusion procedure, said device comprising:
 a perimeter portion including spaced apart elongated members extending along a length of the perimeter portion and opposing end pieces coupled to the elongated members, wherein one of the end pieces includes a channel extending therethrough; and   a center plate member positioned within the perimeter portion and extending along the length of the perimeter portion, said center plate member extending along a central plane of the device between the end pieces of the device, said plate member including an opening proximate the channel so that a bonegraft material introduced through the channel and into the opening is distributed by the plate member to both sides of the plate member and the perimeter portion, wherein the device has a length defined by the distance between the end pieces, a width defined by the width of the elongated members and a height defined by the distance between the elongated members where the height of the device is substantially greater than the width of the device so that the device is operable to be inserted into the disc space in a substantially flat orientation and be rotated to an orientation where the elongated members contact the opposing vertebral bodies.   
     
     
         22 . The device according to  claim 21  wherein the channel is rectangular. 
     
     
         23 . The device according to  claim 21  wherein the elongated members have a plurality of spaced apart ribs defining spaces therebetween. 
     
     
         24 . The device according to  claim 21  wherein the channel extending through the end piece is configured to accept a fill tube that is operable to rotate the device and distribute a bone graft material through the channel and into the device. 
     
     
         25 . The device according to  claim 24  wherein the fill tube includes a pair of opposing clasps that connect to an outside surface of the one end piece. 
     
     
         26 . The device according to  claim 24  wherein the channel is threaded and the fill tube includes a threaded end portion that is operable to be threaded to the threaded channel. 
     
     
         27 . The device according to  claim 24  wherein the channel includes one or more of a slot and an elongated tab and the fill tube includes one or more of a slot and an elongated tab that are configured to engage each other to allow the interbody device to be rotated. 
     
     
         28 . An interbody device assembly for restoring the disc space height of the disc space between two vertebral bodies of adjacent vertebra during a spinal fusion procedure, said assembly comprising:
 an interbody device including a perimeter portion having spaced apart spines extending along a length of the perimeter portion and opposing end pieces coupled to the spines, wherein one of the end pieces includes a channel extending therethrough, and wherein the perimeter portion has a length defined by the distance between the end pieces, a width defined by the width of the spines and a height defined by the distance between the spines where the height of the device is substantially greater than the width of the device, said interbody device further including a center plate positioned within the perimeter portion and including an opening proximate the channel, said center plate extending along the length of the perimeter portion, said center plate extending along a central plane of the device between the end pieces of the device, wherein the device is operable to be inserted between two vertebrae in a disc space and then rotated to restore disc space height; and   a fill tube coupled to the one end piece and in fluid communication with the channel, wherein the fill tube is operable to provide bone graft material to the space within the perimeter portion and the center plate is effective to distribute the bone graft material within the disc space on both sides of the device, said fill tube also being operable to rotate the interbody device.   
     
     
         29 . The assembly according to  claim 28  wherein the spines include a series of ribs defining spaces therebetween extending along a length of the perimeter portion. 
     
     
         30 . The assembly according to  claim 28  wherein the fill tube has a rectangular shape and includes a plurality of fingers that are positioned within slots in an outside surface of the one end piece. 
     
     
         31 . An interbody assembly comprising an interbody device to be positioned within a disc space between two vertebrae, said device including an opening and a center plate extending along the length of the device, said center plate extending along a central plane of the device between ends of the device, said assembly further comprising a fill tube including a fill chamber, said fill tube being coupled to the device so that bone graft material can be passed through the fill chamber in the fill tube and into the opening in the device and being distributed within the disc space on both sides of device by the center plate, said fill tube also being operable to rotate the device. 
     
     
         32 . An interbody device assembly for restoring the disc space height of the disc space between opposing vertebral bodies of adjacent vertebrae during a spinal fusion procedure, the assembly comprising:
 a body having a first end, a second end, a top, and a bottom, the body defining a height and a width, wherein the height is greater than the width, wherein the body is configured to be inserted into the disc space in a substantially flat orientation and to be rotated to an orientation where the top and the bottom contact the opposing vertebral bodies;   wherein the body comprises a distribution feature positioned along a central plane defined by the body, the central plane extending generally from the top to the bottom and from the first end to the second end, the distribution feature configured to distribute bone graft material to either side of the central plane when the top and bottom of the body contact the opposing vertebral bodies.   
     
     
         33 . The interbody device assembly of  claim 32  wherein the distribution feature comprises a nub. 
     
     
         34 . The interbody device assembly of  claim 33  wherein the body comprises a central plate lying along the central plane, and the nub is formed as part of the central plate. 
     
     
         35 . The interbody device assembly of  claim 32  wherein the distribution feature comprises a ridge. 
     
     
         36 . The interbody device assembly of  claim 33  further comprising a fill tube, the fill tube configured to be coupled to the body proximate to one of the first and second ends so that bone graft material can be passed through the fill tube to the distribution feature and be distributed to either side of the central plane by the distribution feature. 
     
     
         37 . The interbody device assembly of  claim 36  wherein the fill tube includes a bore that is substantially open along the length of the bore, wherein the assembly is configured to provide a substantially unimpeded flow path through the bore to the distribution feature when the fill tube is coupled to the interbody device. 
     
     
         38 . The interbody device assembly of  claim 36  wherein the fill tube comprises an end having a shape that conforms with a shape of the distribution feature. 
     
     
         39 . An interbody device for restoring the disc space height of the disc space between opposing vertebral bodies of adjacent vertebrae during a spinal fusion procedure, said device comprising:
 a perimeter portion including spaced apart elongated members extending along a length of the perimeter portion and opposing end pieces coupled to the elongated members, wherein one of the end pieces includes a channel extending therethrough; and   a center plate member positioned within the perimeter portion and extending along the length of the perimeter portion, said center plate member extending along a central plane of the device between the end pieces of the device, said plate member including an opening proximate the channel so that a bonegraft material introduced through the channel and into the opening is distributed by the plate member to both sides of the plate member and the perimeter portion, wherein the device has a length defined by the distance between the end pieces, a width defined by the width of the elongated members and a height defined by the distance between the elongated members.   
     
     
         40 . An interbody device assembly for restoring the disc space height of the disc space between two vertebral bodies of adjacent vertebra during a spinal fusion procedure, said assembly comprising:
 an interbody device including a perimeter portion having spaced apart spines extending along a length of the perimeter portion and opposing end pieces coupled to the spines, wherein one of the end pieces includes a channel extending therethrough, and wherein the perimeter portion has a length defined by the distance between the end pieces, a width defined by the width of the spines and a height defined by the distance between the spines, said interbody device further including a center plate positioned within the perimeter portion and including an opening proximate the channel, said center plate extending along the length of the perimeter portion, said center plate extending along a central plane of the device between the end pieces of the device; and   a fill tube coupled to the one end piece and in fluid communication with the channel, wherein the fill tube is operable to provide bone graft material to the space within the perimeter portion and the center plate is effective to distribute the bone graft material within the disc space on both sides of the device.   
     
     
         41 . An interbody assembly comprising an interbody device to be positioned within a disc space between two vertebrae, said device including an opening and a center plate extending along the length of the device, said center plate extending along a central plane of the device between ends of the device, said assembly further comprising a fill tube including a fill chamber, said fill tube being coupled to the device so that bone graft material can be passed through the fill chamber in the fill tube and into the opening in the device and being distributed within the disc space on both sides of device by the center plate.