Intervertebral implant

Abstract

The present invention provides an intervertebral implant for implantation in a treated area of an intervertebral space between vertebral bodies of a spine. The implant includes a spacer portion having an inferior and superior surface, wherein the inferior and superior surfaces each have a contact area capable of engaging with anatomy in the treated area, and the inferior and superior surfaces define a through-hole extending through the spacer body. The present invention further provides holes extending from a side portion to the inferior and superior surfaces of the spacer portion and a plate portion rigidly coupled to the spacer portion, wherein the plate portion contains holes for receiving screws. A fastener back out prevention mechanism adapted on the plate to prevent the back out of the fasteners from the holes and to secure the spacer to the plate of the intervertebral implant.

What is claimed is: 
     
         1 . An intervertebral implant for implantation in a treated area of an intervertebral space between vertebral bodies of a spine, the implant comprising:
 a spacer having an inferior surface and a superior surface and screw holes extending from an anterior surface of the spacer to the inferior and superior surfaces, wherein the inferior and superior surfaces each have a contact area capable of engaging with anatomy in the treated area, the spacer having a fastener hole at its anterior surface;   a plate coupled to the spacer, the plate having a fastener hole and a plurality of bone screw holes;   a fastener positioned through the fastener holes of the plate and the spacer to secure the plate and the spacer together and to simultaneously act as a bone screw blocker to block a bone screw inserted through one of the bone screw holes.   
     
     
         2 . The intervertebral implant of  claim 1 , wherein the fastener is a screw and the only screw that secures the plate and the spacer together. 
     
     
         3 . The intervertebral implant of  claim 1 , wherein the fastener is a screw and the only screw that secures the plate and the spacer together, and the only screw that acts as the bone screw blocker. 
     
     
         4 . The intervertebral implant of  claim 1 , wherein the plate includes a recess on which the fastener is received and wherein a posterior surface of the plate includes first and second extensions configured to mate with first and a second recesses of the spacer. 
     
     
         5 . The intervertebral implant of  claim 1 , wherein the first and second extensions are curved from a center portion of the posterior surface of the plate to a side surface of the plate and the curved surface corresponds to the curvature of the first and second recesses of the spacer. 
     
     
         6 . The intervertebral implant of  claim 1 , wherein the plate includes a tongue that mates with a first groove in the spacer. 
     
     
         7 . The intervertebral implant of  claim 6 , wherein the tongue of the plate has a curvature and is configured to couple to a first groove of the spacer having a corresponding curvature. 
     
     
         8 . The intervertebral implant of  claim 1 , wherein the fastener includes a pin screw and a nut through which the pin screw is threaded. 
     
     
         9 . The intervertebral implant of  claim 8 , wherein the pin screw includes a head for blocking the bone screw, an unthreaded shaft extending from the head and a threaded portion extending from the unthreaded shaft. 
     
     
         10 . The intervertebral implant of  claim 9 , wherein the head is shaped to block and unblock the bone screw based on a circumferential position of the head. 
     
     
         11 . The intervertebral implant of  claim 9 , wherein the head is shaped to block and unblock two bone screws simultaneously based on a circumferential position of the head. 
     
     
         12 . An intervertebral implant for implantation in a treated area of an intervertebral space between vertebral bodies of a spine, the implant comprising:
 a spacer having an inferior surface and a superior surface and screw holes, and having a fastener hole at its anterior surface;   a plate coupled to the spacer, the plate having a fastener hole and a plurality of bone screw holes;   a fastener positioned through the fastener holes of the plate and the spacer to secure the plate and the spacer together and to simultaneously act as a bone screw blocker to block a bone screw inserted through one of the bone screw holes, the fastener having a head shaped to overlie at least one of the screw holes upon rotation of the fastener.   
     
     
         13 . The intervertebral implant of  claim 12 , wherein the fastener is a screw and the only screw that secures the plate and the spacer together. 
     
     
         14 . The intervertebral implant of  claim 12 , wherein the fastener is a screw and the only screw that secures the plate and the spacer together, and the only screw that acts as the bone screw blocker. 
     
     
         15 . The intervertebral implant of  claim 12 , wherein the plate includes a recess on which the fastener is received and wherein a posterior surface of the plate includes first and second extensions configured to mate with first and a second recesses of the spacer. 
     
     
         16 . The intervertebral implant of  claim 12 , wherein the first and second extensions are curved from a center portion of the posterior surface of the plate to a side surface of the plate and the curved surface corresponds to the curvature of the first and second recesses of the spacer. 
     
     
         17 . The intervertebral implant of  claim 12 , wherein the plate includes a tongue that mates with a first groove in the spacer. 
     
     
         18 . The intervertebral implant of  claim 17 , wherein the tongue of the plate has a curvature and is configured to couple to a first groove of the spacer having a corresponding curvature. 
     
     
         19 . The intervertebral implant of  claim 12 , wherein the fastener includes a pin screw and a nut through which the pin screw is threaded. 
     
     
         20 . The intervertebral implant of  claim 19 , wherein the pin screw includes an unthreaded shaft extending from the head and a threaded portion extending from the unthreaded shaft.