Stand alone anterior cage

Abstract

The present invention teaches an improved spinal fusion implant and method of implanting same. The implant includes a shell and an insert, the insert capable of situating first and second plates of the shell with respect to each other and of preventing unwanted loosening of fasteners placed through the shell and into the adjacent vertebral bodies. The method includes implanting a shell, selecting an insert from a plurality of inserts, and placing an insert between first and second plates of the shell.

1 . A spinal implant for fusing together first and second vertebral bodies, the implant comprising:
 a first member having a first surface for engaging the first vertebral body, a second surface, and a first opening extending between the first and second surfaces;   a second member having a third surface for engaging the second vertebral body, a fourth surface, and a second opening extending between the third and fourth surfaces;   a living hinge connecting the first and second members and allowing for movement of the first and second members with respect to one another; and   an insert disposed between the first and second members, the insert covering the first and second openings about the second and fourth surfaces.   
     
     
         2 . The spinal implant of  claim 1 , wherein one of the second or fourth surfaces includes a projection for retaining the insert between the first and second members. 
     
     
         3 . The spinal implant of  claim 2 , wherein each of the second and fourth surfaces include projections. 
     
     
         4 . The spinal implant of  claim 1 , wherein the insert is constructed of bone. 
     
     
         5 . The spinal implant of  claim 1 , wherein the insert is constructed of a polymer. 
     
     
         6 . The spinal implant of  claim 1 , wherein the insert is constructed of a metal. 
     
     
         7 . The spinal implant of  claim 1 , further comprising a first screw disposed in the first opening and a second screw disposed in the second opening. 
     
     
         8 . The spinal implant of  claim 7 , wherein the insert includes a portion for preventing back out of the first and second screws. 
     
     
         9 . The spinal implant of  claim 1 , further comprising a third opening extending between the first and second surfaces of the first member, and a fourth opening extending between the third and fourth surfaces of the second member. 
     
     
         10 . The spinal implant of  claim 9 , wherein the insert includes a main body, a first portion for covering the first and second openings and a second portion for covering the third and fourth openings. 
     
     
         11 . The spinal implant of  claim 10 , wherein the main body of the insert includes an aperture for engagement with a tool. 
     
     
         12 . The spinal implant of  claim 10 , further comprising a first screw disposed in the first opening, a second screw disposed in the second opening, a third screw disposed in the third opening, and a fourth screw disposed in the fourth opening. 
     
     
         13 . The spinal implant of  claim 12 , wherein the insert includes a first portion for preventing back out of the first and second screws and second portion for preventing back out of the third and fourth screws. 
     
     
         14 . The spinal implant of  claim 13 , further comprising a bone growth aperture extending through the first member, the insert, and the second member. 
     
     
         15 . The spinal implant of  claim 1 , wherein the first and second surfaces are located in non-parallel planes. 
     
     
         16 . The spinal implant of  claim 15 , wherein the insert forces non-parallel relationship between the first and second surfaces. 
     
     
         17 . A spinal implant for implantation between first and second vertebral bodies, the implant comprising:
 a shell including:
 a first plate for engaging the first vertebral body, the first plate including a first hole formed therethrough; 
 a second plate for engaging the second vertebral body, the second plate including a second hole formed therethrough; and 
   a resilient member connecting the first and second plates; and   an insert including:   a main body; and
 a portion capable of covering at least one of the first or second holes when the insert is disposed between the first and second plates. 
   
     
     
         18 . The spinal implant of  claim 17 , further comprising a first screw disposed in the first hole and second screw disposed in the second hole. 
     
     
         19 . The spinal implant of  claim 18 , wherein the portion is capable of preventing back out of both of the first and second screws when the insert is disposed between the first and second plates. 
     
     
         20 . The spinal implant of  claim 17 , wherein the insert is constructed at least partially from materials selected from the group consisting of bone, polymer, and metal. 
     
     
         21 . The spinal implant of  claim 17 , wherein one of the first or second plates includes a projection for retaining the insert between the first and second plates. 
     
     
         22 . The spinal implant of  claim 21 , wherein each of the first and second plates include projections. 
     
     
         23 . The spinal implant of  claim 17 , further comprising a third hole formed through the first plate and a fourth hole formed through the second plate. 
     
     
         24 . The spinal implant of  claim 23 , furthering comprising a first screw disposed in the first hole, a second screw disposed in the second hole, a third screw disposed in the third hole, and fourth screw disposed in the fourth hole. 
     
     
         25 . The spinal implant of  claim 24 , wherein the insert includes a first portion for preventing back out of the first and second screws and second portion for preventing back out of the third and fourth screws. 
     
     
         26 . The spinal implant of  claim 17 , further comprising a bone growth aperture extending through the first member, the insert, and the second member. 
     
     
         27 . The spinal implant of  claim 17 , wherein the main body of the insert includes an aperture for engagement with a tool. 
     
     
         28 . The spinal implant of  claim 17 , wherein the first and second plates are located in non-parallel planes. 
     
     
         29 . The spinal implant of  claim 28 , wherein the insert forces non-parallel relationship between the first and second plates. 
     
     
         30 . A method of fusing together first and second vertebral bodies, the method comprising:
 preparing a space between the first and second vertebral bodies to accept a spinal implant;   implanting a shell, the shell including a first plate, and second plate, and a living hinge connecting the first and second plates;   placing a first screw through the first plate and into the first vertebral body;   placing a second screw through the second plate and into the second vertebral body; and   inserting an insert between the first and second plates, wherein the insert prevents back out of the first and second screws.   
     
     
         31 . The method of  claim 30 , wherein the inserting step causes the first and second plates to move with respect to each other, wherein the movement between the first and second plates is translated to the first and second vertebral bodies. 
     
     
         32 . The method of  claim 30 , further comprising the step of choosing the insert from a plurality of inserts. 
     
     
         33 . The method of  claim 30 , further comprising the steps of placing a third screw through the first plate and into the first vertebral body, and placing a fourth screw through the second plate and into the second vertebral body. 
     
     
         34 . The method of  claim 33 , wherein the insert prevents back out of the first, second, third, and fourth screws. 
     
     
         35 . The method of  claim 30 , further comprising the step of retaining the insert between the first and second plates. 
     
     
         36 . The method of  claim 35 , wherein the retaining step includes engaging the insert with projections formed on the first and second plates. 
     
     
         37 . The method of  claim 30 , further comprising the step of allowing bone growth through an aperture formed through the first plate, the insert, and the second plate.