Artificial disc implant

Abstract

An artificial disc implant includes an upper shell, a lower shell, and a spacer therebetween. The spacer preferably has properties similar to that of a natural spinal disc, while the upper and lower shells form a rigid interface between the implant and the adjacent vertebral bodies. The upper and lower shells can be configured to prevent expulsion of the spacer from the disc space. The implant upper and lower shells may further be configured into partially cylindrical shapes for ease of insertion through an insertion tube as presently known for interbody fusion devices. The devices may further be configured for insertion through a double-barreled insertion tube. Methods and instruments for inserting an artificial disc implant are also provided.

1 - 42 . (canceled)  
   
   
       43 . A method for inserting an artificial disc implant into a spinal disc space, comprising: 
 accessing the disc space;    inserting a sleeve adjacent the disc space, the sleeve having a working channel extending between a proximal end and a distal end;    preparing an implant insertion location in the disc space through the sleeve;    providing an implant having an upper shell, a lower shell, and an elastic spacer between the upper shell and the lower shell;    applying a compressive force to the implant to compress the elastic spacer between the upper and lower shells;    inserting the implant in the working channel of the sleeve; and    pushing the implant through the working channel and into the implant insertion location in the disc space.    
   
   
       44 . The method of  claim 43 , wherein providing an implant includes providing the implant with a substantially cylindrical shape.  
   
   
       45 . The method of  claim 44 , wherein: 
 accessing the disc space includes accessing the disc space from a posterior approach; and    the sleeve includes a cylindrical working channel.    
   
   
       46 . The method of  claim 45 , further comprising: 
 accessing the disc space at a second location;    inserting a sleeve adjacent the disc space at the second location, the sleeve having a cylindrical working channel extending between a proximal end and a distal end;    preparing a second implant insertion location in the disc space through the sleeve;    providing a second implant having an upper shell, a lower shell, and an elastic spacer between the upper shell and the lower shell;    applying a compressive force to the second implant to compress the elastic spacer between the upper and lower shells;    inserting the second implant in the working channel of the sleeve; and    pushing the second implant through the working channel and into the second implant insertion location in the disc space.    
   
   
       47 . The method of  claim 43 , wherein the sleeve is a double barrel sleeve having a pair of adjacent working channels.  
   
   
       48 . The method of  claim 47 , wherein providing an implant includes providing the implant with the upper shell and the lower shell, each shell including a pair of partially cylindrical lobes interconnected by an intermediate portion, the implant being configured for insertion through the adjacent working channels of the sleeve as a single unit.  
   
   
       49 . The method of  claim 47 , wherein accessing the disc space includes accessing the disc space from a lateral approach.  
   
   
       50 . The method of  claim 47 , wherein accessing the disc space includes accessing the disc space from an anterior-lateral approach.  
   
   
       51 . The method of  claim 47 , wherein accessing the disc space includes accessing the disc space from an anterior approach.  
   
   
       52 - 53 . (canceled)  
   
   
       54 . A method for inserting an artificial disc implant into a spinal disc space, comprising: 
 inserting a sleeve adjacent the spinal disc space, the sleeve having adjacent working channels extending between a proximal end and a distal end, said adjacent working channels each being substantially cylindrical in shape along at least a portion of said sleeve;    providing an implant having an upper shell, a lower shell, and an elastic spacer between the upper shell and the lower shell, the implant being sized for positioning simultaneously in the adjacent working channels;    compressing the elastic spacer between the upper and lower shells;    inserting the implant in the working channels of the sleeve; and    delivering the implant through the working channels and into an implant insertion location in the disc space.    
   
   
       55 . The method of  claim 54 , wherein providing an implant includes providing the implant with the upper shell and the lower shell, each shell including a pair of partially cylindrical lobes interconnected by an intermediate portion, the implant being configured for insertion through the adjacent working channels of the sleeve as a single unit.  
   
   
       56 . The method of  claim 54 , further comprising accessing the disc space from a lateral approach.  
   
   
       57 . The method of  claim 54 , further comprising accessing the disc space from an anterior-lateral approach.  
   
   
       58 . The method of  claim 54 , further comprising accessing the disc space from an anterior approach.  
   
   
       59 . The method of  claim 54 , wherein the elastic spacer is compressed as the implant is inserted into the working channels.  
   
   
       60 . A method for inserting an artificial disc implant into a spinal disc space, comprising: 
 inserting a sleeve adjacent the spinal disc space, the sleeve having a working channel extending between a proximal end and a distal end;    providing an implant having an upper shell, a lower shell, and an elastic spacer between the upper shell and the lower shell;    compressing the elastic spacer between the upper and lower shells;    inserting the implant in the working channel of the sleeve; and    delivering the implant through the working channel and into an implant insertion location in the disc space, wherein when delivered the elastic spacer returns toward its uncompressed condition and engages the upper and lower shells to an adjacent endplate of vertebrae on each side of the spinal disc space.    
   
   
       61 . The method of  claim 60 , wherein providing the implant includes providing the implant with a substantially cylindrical shape.  
   
   
       62 . The method of  claim 60 , further comprising accessing the disc space the disc space from a posterior approach and wherein the sleeve includes a cylindrical working channel.  
   
   
       63 . The method of  claim 60 , further comprising: 
 inserting a sleeve adjacent a second implant insertion location of the spinal disc space, the sleeve having a cylindrical working channel extending between a proximal end and a distal end;    providing a second implant having an upper shell, a lower shell, and an elastic spacer between the upper shell and the lower shell;    compressing the elastic spacer between the upper and lower shells of the second implant;    inserting the second implant in the working channel of the sleeve; and    delivering the second implant through the working channel and into the second implant insertion location.    
   
   
       64 . The method of  claim 60 , further comprising: 
 preparing the implant insertion location in the spinal disc space through the sleeve before inserting the implant in the spinal disc space.