Spinal implant

Abstract

An implant is disclosed for use in spinal stabilization. In one preferred embodiment, the implant is described as including a hollow, cylindrical body having external threading and a plurality of openings formed radially through the body in communication with the body interior. The holes are positioned to chip bone into the implant as the implant is rotated.

What is claimed is:  
     
         1 . An implant for insertion into a bore formed between opposing vertebrae of a spine where said vertebrae are separated by a spacing, said implant comprising: 
 a rigid body having a leading end and a trailing end spaced apart by a longitudinal axis of said body;    said body comprising at least exposed threads disposed at least partially between said leading end and said trailing end, said threads selected to engage vertebra material and draw said body along a direction of said axis upon rotation of said body about said axis;    said body having a hollow, generally cylindrical shell with said threads disposed on an exterior surface of said shell;    said body having means defining a chamber disposed within said body and said body is provided with a rib disposed within said cylindrical shell;    said body having means defining at least one opening formed through said body in communication with said chamber and with said opening extending generally radially to said axis; and    said body sized to have a dimension generally transverse to said longitudinal dimension selected to be greater than said spacing for said body to urge said opposing vertebrae apart upon insertion of said body between said vertebrae with a portion of said body opposing a first of said opposing vertebrae and with an opposite side of said body opposing a second of said opposing vertebrae.    
     
     
         2 . An implant for insertion into a bore formed between opposing vertebrae of a spine where said vertebrae are separated by a spacing, said implant comprising: 
 a rigid body having a leading end and a trailing end spaced apart by a longitudinal axis of said body;    said body comprising at least exposed threads disposed at least partially between said leading end and said trailing end, said threads selected to engage vertebra material and draw said body along a direction of said axis upon rotation of said body about said axis;    said body having a hollow, generally cylindrical shell with said threads disposed on an exterior surface of said shell;    said body having means defining a chamber disposed within said body;    said body having means defining at least one opening formed through said body in communication with said chamber and with said opening extending generally radially to said axis said opening comprising a hole formed through said shell with said hole disposed with an axis offset from said longitudinal axis; and    said body sized to have a dimension generally transverse to said longitudinal dimension selected to be greater than said spacing for said body to urge said opposing vertebrae apart upon insertion of said body between said vertebrae with a portion of said body opposing a first of said opposing vertebrae and with an opposite side of said body opposing a second of said opposing vertebrae.    
     
     
         3 . An implant for insertion into a bore formed between opposing vertebrae of a spine where said vertebrae are separated by a spacing, said implant comprising: 
 a rigid body having a leading end and a trailing end spaced apart by a longitudinal axis of said body;    said body comprising at least exposed threads disposed at least partially between said leading end and said trailing end, said threads selected to engage vertebra material and draw said body along a direction of said axis upon rotation of said body about said axis;    said body having a hollow, generally cylindrical shell with said threads disposed on an exterior surface of said shell;    said body having means defining a chamber disposed within said body;    said body having means defining at least one opening formed through said body in communication with said chamber and with said opening extending generally radially to said axis;    said body sized to have a dimension generally transverse to said longitudinal dimension selected to be greater than said spacing for said body to urge said opposing vertebrae apart upon insertion of said body between said vertebrae with a portion of said body opposing a first of said opposing vertebrae and with an opposite side of said body opposing a second of said opposing vertebrae; and    indicator means for indicating an alignment of said body, said opening comprising holes formed through said shell and said holes including a first plurality disposed in alignment with said indicator and a second plurality disposed transverse to said indicator, said first plurality having openings sized greater than openings of said second plurality.    
     
     
         4 . An implant for insertion into a bore formed between opposing vertebra of a spine, said implant comprising: 
 a rigid body having a leading end and a trailing end spaced apart by longitudinal axis of said body;    said body having exposed threads disposed at least partially between said leading end and said trailing end, said threads selected to engage a vertebra material and draw said body along a direction of said axis upon rotation of said body about said axis;    said body having means defining a chamber disposed within said body;    said body having a plurality of holes formed through said body in communication with said chamber, said holes disposed with a hole axis offset from said longitudinal axis.    
     
     
         5 . An implant for insertion into a bore formed between opposing vertebra of a spine, said implant comprising: 
 a rigid body having a leading end and a trailing end spaced apart by a longitudinal axis of said body;    said body having exposed threads disposed at least partially between said leading end and said trailing end, said threads selected to engage a vertebra material and draw said body along a direction of said axis upon rotation of said body about said axis.    said body having means defining a chamber disposed within said body;    said body having means defining a plurality of holes formed through said body in communication with said chamber;    indicator means for indicating an alignment of said body with respect to said vertebra; and    said holes including at least a first plurality disposed in alignment with said indicator and a second plurality disposed out of alignment with said indicator.    
     
     
         6 . An implant according to  claim 5  wherein said first plurality have opening size greater than openings of said second plurality.