Central Structures Spreader for the Lumbar Spine

Abstract

A spinal device and associated method are provided for spreading of first and second vertebral elements, each of the first and second vertebral elements having a circumferential surface defining a vertebral body and a pedicle having a pedicle root portion adjacent the circumferential surface. The device includes a first end member having at least one surface adapted to conform to at least one of the circumferential surface and the pedicle root portion of the first vertebral element, and a second end member having at least one surface adapted to conform to at least one of the circumferential surface and the pedicle root portion of the second vertebral element. The device further includes a resilient member extending between the first and second end members and being adapted to exert a force against the first and second vertebral elements.

What is claimed is: 
     
         1 . A spinal device for spreading first and second vertebral elements of a spine, comprising:
 a first end member insertable into a lateral aspect of the spine adjacent the first vertebral element;   a second end member insertable into a lateral aspect of the spine adjacent the second vertebral element;   a first fastener adapted to secure the first end member to the first vertebral element;   a second fastener adapted to secure the second end member to the second vertebral element; and   a resilient member having a longitudinal axis extending from the first end member to the second end member;   wherein the spinal device is configured to allow movement between the first and second vertebral elements.   
     
     
         2 . The spinal device of  claim 1 , wherein the first end member includes a surface adapted to conform to an outer lateral surface of the first vertebral element. 
     
     
         3 . The spinal device of  claim 1 , wherein the second end member includes a surface adapted to conform to an outer lateral surface of the second vertebral element. 
     
     
         4 . The spinal device of  claim 1 , wherein the resilient member is adjustable to define a distance between the first end member and the second end member. 
     
     
         5 . The spinal device of  claim 1 , wherein the first end member includes a laterally projecting flange having an aperture extending therethrough, the aperture configured to receive the first fastener therein. 
     
     
         6 . The spinal device of  claim 1 , wherein the second end member includes a laterally projecting flange having an aperture extending therethrough, the aperture configured to receive the second fastener therein. 
     
     
         7 . A spinal device for spreading first and second vertebral elements of a spine, comprising:
 a first end member insertable into a lateral aspect of the spine adjacent the first vertebral element;   a second end member insertable into a lateral aspect of the spine adjacent the second vertebral element;   a first fastener adapted to secure the first end member to the first vertebral element;   a second fastener adapted to secure the second end member to the second vertebral element; and   an elastic member coupled to the first end member and the second end member;   wherein the spinal device is configured to allow movement between the first and second vertebral elements.   
     
     
         8 . The spinal device of  claim 7 , wherein the first and second fasteners are bone screws. 
     
     
         9 . The spinal device of  claim 7 , wherein an axial position of the elastic member with respect to the first end member is adjustable. 
     
     
         10 . The spinal device of  claim 7 , wherein the first end member and the second end member each include a bottom face configured to conform to the first vertebral element and the second vertebral element, respectively. 
     
     
         11 . The spinal device of  claim 10 , wherein the first fastener is configured to secure the bottom face of the first end member against the first vertebral element, and the second fastener is configured to secure the bottom face of the second end member against the second vertebral element. 
     
     
         12 . The spinal device of  claim 7 , wherein the elastic member exerts a distraction force against the first end member and the second end member. 
     
     
         13 . A method of spreading first and second vertebral elements of a spinal column, comprising:
 securing a first end member to a first side of the first vertebral element;   coupling a first end of a flexible intermediate member to the first end member;   securing a second end member to a first side of the second vertebral element, wherein the first sides of the first and second vertebral elements are on one side of the spinal column;   coupling a second end of the flexible intermediate member to the second end member; and   positioning the flexible intermediate member such that the flexible intermediate member applies a distraction force to the first and second vertebral elements;   wherein the flexible intermediate member is configured to permit movement between the first and second vertebral elements allowing for natural alignment of the first and second vertebral elements.   
     
     
         14 . The method of  claim 13 , wherein the first end member includes a laterally projecting flange having a first aperture configured to receive a first fastener therethrough, the first fastener being adapted to secure the first end member to the first vertebral element; and
 wherein the second end member includes a laterally projecting flange having a second aperture configured to receive a second fastener therethrough, the second fastener being adapted to secure the second end member to the second vertebral element.   
     
     
         15 . The method of  claim 13 , wherein the first and second end members each include a bottom face configured to conform to an outer surface of the first and second vertebral elements, respectively. 
     
     
         16 . The method of  claim 15 , wherein the bottom face of the first end member is secured against an outer surface of the first vertebral element, and the bottom face of the second end member is secured against an outer surface of the second vertebral element. 
     
     
         17 . The method of  claim 13 , wherein an axial position of the flexible intermediate member relative to the first end member is adjustable to control an exposed length of the flexible intermediate member between the first vertebral element and the second vertebral element. 
     
     
         18 . The method of  claim 17 , wherein movement of the flexible intermediate member with respect to the first end member is limited to one direction. 
     
     
         19 . The method of  claim 18 , wherein the one direction is away from the first end member and toward the second end member. 
     
     
         20 . The method of  claim 13 , further comprising:
 securing a third end member to a second side of the first vertebral element;   coupling a first end of a second flexible intermediate member to the third end member;   securing a fourth end member to a second side of the second vertebral element;   coupling a second end of the second flexible intermediate member to the fourth end member; and   positioning the second flexible intermediate member such that the second flexible intermediate member applies a distraction force to the first and second vertebral elements;   wherein the second sides of the first and second vertebral elements are on one side of the spinal column are generally opposite the first sides of the first and second vertebral elements.