Expandable tissue spacer implant and method of use

Abstract

A horizontal and vertical expandable tissue spacer implants, insertion tools, assembly methods and surgical methods are disclosed. The horizontal expandable tissue spacer implant includes a first lateral member with a first side, a second lateral member with a first side, and an intermediate spacer member. The intermediate spacer member is adapted to cooperatively engage and hold the first side of the first lateral member and the first side of the second lateral member. A vertical expandable tissue spacer implant includes a top member with a bottom surface, a bottom member with a top surface, and an intermediate spacer member with a coupling mechanism. The coupling mechanism cooperatively engages the bottom surface of the top member to the intermediate spacer member and the top surface of the bottom member to the intermediate spacer member.

What is claimed is: 
     
         1 . A horizontal expandable tissue spacer implant, the implant comprising:
 a first lateral member with a first side;   a second lateral member with a first side;   an intermediate spacer member being adapted to cooperatively engage and hold the first side of the first lateral member and the first side of the second lateral member, wherein the intermediate spacer member includes an inner cavity defined by a top side opposite a bottom side and a front side opposite a rear side, wherein the rear side includes a tapered opening extending across the entire rear side; and   a spacer insert for insertion into the inner cavity of the intermediate spacer member, wherein the spacer insert engages at least a portion of the front side of the inner cavity and at least a portion of the rear side of the inner cavity.   
     
     
         2 . The implant of  claim 1 , wherein the intermediate spacer member, the first lateral member, and the second lateral member each have a generally rectangular outside perimeter. 
     
     
         3 . The implant of  claim 2 , wherein the spacer insert has a generally rectangular outside perimeter. 
     
     
         4 . The implant of  claim 3 , further comprising:
 a threaded rod for engaging the intermediate spacer member and the spacer insert to activate a coupling mechanism.   
     
     
         5 . The implant of  claim 1 , further comprising:
 a coupling mechanism, wherein the coupling mechanism, comprises:
 two pairs of projections on the intermediate spacer member; 
 a pair of projections on the first side of the first lateral member; and 
 a pair of projections on the first side of the second lateral member. 
   
     
     
         6 . The implant of  claim 5 , wherein the two pairs of projections include a first pair of projections on a first side of the intermediate spacer member and a second pair of projections on a second side of the intermediate spacer member. 
     
     
         7 . The implant of  claim 6 , wherein the first pair of projections of the intermediate spacer member engages the corresponding pair of projections on the first side of the first lateral member and the second pair of projections of the intermediate spacer member engages the corresponding pair of projections on the first side of the second lateral member. 
     
     
         8 . The implant of  claim 1 , wherein the spacer insert comprises:
 a first end with an opening configured to engage the threaded rod; and   a second end configured with at least two angled portions for contacting the tapered opening of the intermediate spacer member, wherein the second end of the spacer insert extends into the tapered opening of the intermediate spacer member.   
     
     
         9 . The implant of  claim 7 , wherein the two pairs of projections of the intermediate spacer member, the pair of projections on the first side of the first lateral member, and the pair of projections on the second lateral member comprise dovetails. 
     
     
         10 . An expandable tissue spacer implant, the implant comprising:
 a top member with a bottom surface;   a bottom member with a top surface;   a lateral member with a first side; and   an intermediate spacer member having coupling members, wherein the coupling members cooperatively engage the bottom surface of the top member to the intermediate spacer member, the top surface of the bottom member to the intermediate spacer member, and the first side of the lateral member to the intermediate spacer member.   
     
     
         11 . The implant of  claim 10 , wherein the coupling members, comprises:
 two pairs of projections disposed on the intermediate spacer member;   a pair of projections disposed on the bottom surface of the top member;   a pair of projections disposed on the top surface of the bottom member; and   a pair of projections disposed on the first side of the lateral member.   
     
     
         12 . The implant of  claim 11 , wherein the two pairs of projections include a first pair of projections on a top side of the intermediate spacer member and a second pair of projections on a bottom side of the intermediate spacer member. 
     
     
         13 . The implant of  claim 12 , wherein the first pair of projections of the intermediate spacer member engage at least a portion of the pair of projections on the bottom surface of the top member and the second pair of projections of the intermediate spacer member engage at least a portion of the pair of projections on the top surface of the bottom member. 
     
     
         14 . The implant of  claim 13 , wherein the pair of projections of the lateral member engage at least a portion of one of the projections on the bottom surface of the top member and at least a portion of one of the projections on the top surface of the bottom member. 
     
     
         15 . The implant of  claim 13 , wherein the intermediate spacer member further comprises a passageway on a front wall and the lateral member further comprises an opening on a front wall. 
     
     
         16 . The implant of  claim 15 , further comprising:
 a locking mechanism with a head portion for engaging the front wall of the lateral member and an extension portion for insertion into the passageway of the intermediate spacer member.   
     
     
         17 . The implant of  claim 16 , wherein the locking mechanism further comprises two legs each with a protrusion for engaging the top member and the bottom member. 
     
     
         18 . The implant of  claim 10 , wherein the lateral member further comprises an engagement member extending from the inner side and forming a front wall of the lateral member, wherein an interior surface of the engagement member engages a portion of the front wall of the intermediate spacer member. 
     
     
         19 . The implant of  claim 11 , wherein the projections comprise dovetails. 
     
     
         20 . A surgical method for maintaining a space between two tissue bodies in a living being, comprising:
 obtaining a medical device comprising:
 a first member; 
 a second member; and 
 an intermediate spacer member having a coupling mechanism, wherein the coupling mechanism slidingly couples the first member to the intermediate spacer member and the second member to the intermediate spacer member; 
   coupling the first and second members to an insertion instrument;   positioning and inserting the insertion instrument with the coupled first and second members into a space between the two tissue bodies to maintain or increase the space therebetween;   slidingly inserting the intermediate spacer member within the insertion instrument and into the space between the first and second members; and   securing the intermediate spacer member to the two first and second members.