Mechanical Apparatus and Method for Artificial Disc Replacement

Abstract

The present invention relates to a device and method to 1) facilitate disk fusion, 2) perform an artificial replacement of the nucleus, 3) perform an artificial replacement of the annulus, or 4, perform an artificial replacement of both the nucleus and annulus. The device is designed to be placed into the inter-vertebral space following discectomy. The invention includes a delivery catheter and an expandable continuous mesh loop that has a torus configuration with a lumen within the mesh and a central hole. The mesh loop can be diametrically increased or contracted in diameter by the control element acting on the mesh loop. The mesh loop may be formed of a woven or braided material from a polymer such as PEEK (polyetheretherketone), nylon, polyurethane, polyester, polyethylene, polypropylene or any other biocompatible polymer, or formed from a metallic braid of stainless steel, Elgiloy, Nitinol, or any other biocompatible metal.

1 . A spinal disc device comprising:
 a flexible and expandable expansile loop, said expansile loop having an interior section in slidable cooperation with an outer section, said expansile loop composed of a woven, knitted, or braided material in a tubular or flatten form, said expansile loop further having an interior chamber, wherein said expansile loop is designed to be filled with a biocompatible material(s);   said outer section of said expansile loop having a inside surface and an outer opening;   said interior section of said expansile loop having an outside surface and a distal end;   a first flexible control element, said control element having a distal end, a distal section, and a proximal section, said distal end of said control element in communication with said distal end of said interior section of said expansile loop, said control element looping around said inside surface of said expansile loop whereby said distal section of said control element is located within said interior chamber and said proximal section of said control element exits said expansile loop at said outer opening;   a second flexible control element, said control element having a distal end, said distal end of said control element attached to said distal end of said interior section of said expansile loop, and said first and second flexible control elements in cooperation with said expansile loop, whereby said first and second flexible control elements are designed to mechanically expand said expansile loop without pressurization within an inter-vertebral disc.   
     
     
         2 . The spinal disc device as recited in  claim 1 , further comprising an outer sheath, said outer sheath having an inner lumen. 
     
     
         3 . The spinal disc device as recited in  claim 2 , whereby said spinal disc device is contained within said inner lumen of said outer sheath when said spinal disc device is in a contracted delivery configuration. 
     
     
         4 . The spinal disc device as recited in  claim 1 , wherein said expansile loop is composed of braided material in a tubular form. 
     
     
         5 . The spinal disc device as recited in  claim 1 , wherein said expansile loop is composed from a polymeric material. 
     
     
         6 . The spinal disc device as recited in  claim 1 , wherein said expansile loop is composed from a metallic material. 
     
     
         7 . The spinal disc device as recited in  claim 1 , wherein said control elements are composed from a polymeric material. 
     
     
         8 . The spinal disc device as recited in  claim 1 , wherein said control elements are composed from a metallic material. 
     
     
         9 . The spinal disc device as recited in  claim 3 , wherein said spinal disc device attains an expanded configuration when expelled from said outer sheath. 
     
     
         10 . The spinal disc device as recited in  claim 1 , wherein said expansile loop forms a substantially circular shape when said interior section coaxially engages said outer section. 
     
     
         11 . The spinal disc device as recited in  claim 1 , further comprising an inner chamber which is substantially continuous around said substantially circular shape. 
     
     
         12 . The spinal disc device as recited in  claim 1 , further comprising the function to deliver within said inner chamber a biocompatible material to the inter-vertebral space. 
     
     
         13 . The spinal disc device as recited in  claim 10 , wherein said inner chamber is filled with a polymeric material. 
     
     
         14 . The spinal disc device as recited in  claim 12 , wherein one or more of said biocompatible materials is formed of a material selected from the group consisting of hydrophilic polymers, hydrogels, homopolymer hydrogels, copolymer hydrogels, multi-polymer hydrogels, or interpenetrating hydrogels, acrylonitrile, acrylic acid, acrylimide, acrylimidine, including but not limited to PVA, PVP, PHEMA, PNVP, polyacrylainides, poly(ethylene oxide), polyvinyl alcohol, polyarylonitrile, and polyvinyl pyrrolidone, silicone, polyurethanes, polycarbonate-polyurethane (e.g., Corethane) other biocompatibile polymers, or combinations thereof. 
     
     
         15 . The spinal disc device as recited in  claim 12 , wherein one or more of said biocompatible materials is formed of a material that is allowed to expand through the adsorption of liquids such as water selected from the group consisting of polyacrliamide, polyacrylonitrile, polyvinyl alcohol or other biocompatible hydrogels, solid fibrous collagen or other suitable hydrophilic biocompatible material or combinations thereof. 
     
     
         16 . The spinal disc device as recited in  claim 12 , wherein one or more biocompatible materials is formed of a material selected from the group consisting of steroids, antibiotics, tissue necrosis factor alpha or its antagonists, analgesics, growth factors, genes or gene vectors in solution; biologic materials (hyaluronic acid, non-crosslinked collagen, fibrin, liquid fat or oils); synthetic polymers (polyethylene glycol, liquid silicones, synthetic oils), saline or combinations thereof. 
     
     
         17 . The spinal disc device as recited in  claim 12 , wherein one or more biocompatible materials is formed of a material selected from the group consisting of bone graft materials such as any described “bone cements” or any polymeric bone graft compounds, bone graft materials, nylon fibers, carbon fibers, glass fibers, collagen fibers, ceramic fibers, polyethylene fibers, poly(ethylene terephthalate), polyglycolides, polylactides, and combinations thereof. 
     
     
         18 . The spinal disc device as recited in  claim 1 , wherein said spinal disc device is adapted to promote spinal fixation between two adjacent vertebral bodies. 
     
     
         19 . The spinal disc device as recited in  claim 1 , wherein said spinal disc device is deformable to conform to an interior region of a vertebral disc. 
     
     
         20 . The spinal disc device as recited in  claim 12 , wherein said spinal disc device is adapted to inject a volume of biocompatible material into said inner chamber of said expansile loop until a desired disc height is achieved. 
     
     
         21 . The spinal disc device as recited in  claim 12 , wherein said spinal disc device is adapted to inject an volume of biocompatible material into said inner chamber of said expansile loop until a desired disc pressure is achieved.