Bone screw systems and methods of use

Abstract

A bone plating system is provided that permits maintenance of a compression force while also accommodating bony subsidence, among other features. Methods of implantation are also provided that improve alignment and placement during implantation and avoid maneuvers that weaken the vertebral bodies. A modular distraction screw is placed during the initial stages of surgery when all relevant landmarks are still intact. After completion of the surgical bone work, a proximal end of the distraction screw is detached, leaving a protruding distal segment implanted in the centerline of the vertebral bodies above and below the newly fused disc space. A bone plate is guided into proper position relative to the upper and lower vertebra by attaching the bone plate to the protruding distal segments. The distal segments of the distraction screws are tightened onto the plate and the plate is held stationary while bone screws are placed. The bone plating system is also extendable, allowing additional bone plates to be placed and coupled with existing plate components to create a multi-level plating system. Additional bone plates may be placed contemporaneously or during a subsequent surgical procedure.

1 . An orthopedic implant adapted to fixate at least three skeletal bones of a human or animal subject, comprising: 
 a connector adapted to connect a plurality of bone anchors, the connector having a slotted bore hole, wherein at least one bone anchor is positioned into each of a skeletal bone, wherein the connector is adapted to allow movement between at least three skeletal bones wherein movement between at least one set of immediately adjacent bones is provided by movement between a connector segment attached to a first bone and another connector segment attached to a second bone,    and wherein movement between at least a second set of immediately adjacent bones is provided by movement of at least one bone anchor within the slotted bore hole wherein the bore is contained within a single plate segment that inter-connects both bones of the second set of adjacent bones.    
   
   
       2 . A method for the manipulation and movement of a first vertebral bone relative to an adjacent set of vertebral bones that have been collectively inter-connected by a first orthopedic implant at a first operation, comprising: 
 coupling an extension member to an aperture of the first orthopedic implant while the first orthopedic implant remains attached to the inter-connected set of vertebral bodies; and    applying a force onto the extension member so as to produce collective movement of the set of inter-connected vertebral bodies relative to the first vertebral body.    
   
   
       3 . A method as in  claim 2 , further comprising: 
 distracting a disc space that is anatomically positioned between the first vertebral body and the adjacent set of inter-connected vertebral bodies; and    producing a bone fusion across the disc space.    
   
   
       4 . A method as in  claim 2 , further comprising: 
 placing a second orthopedic implant between the first vertebral body and the adjacent set of inter-connected vertebral bodies.    
   
   
       5 . A method for the positioning of a vertebral bone connector that is used to fixate at least two vertebral bones wherein at least one bone distraction screw is placed into each of an upper most and a lower most of the fixated vertebral bones, the method comprising: 
 actuating a bone distraction screw to position the bones in a desired spatial configuration relative to one another;    positioning at least one end of the vertebral bone connector onto a distraction screw so that a segment of the distraction screw transverses a slotted bore hole contained on an end of the connector, wherein the slotted bore hole is adapted to interact with at least a segment of the distraction screw to permit the connector to move relative to the underlying bone in a first plane while limiting movement in a second plane;    moving the connector in the first plane until a desired connector position is achieved; and    actuating a distraction screw segment so as to immobilize the connector relative to the underlying bone.    
   
   
       6 . A method as in  claim 5 , further comprising: 
 surgically manipulating at least one disc space that is positioned between an upper most vertebral bone that is attached to a distraction screw and a lower most vertebral bones that is attached to a distraction screw, wherein the manipulation is performed prior to placement of the connector device.    
   
   
       7 . A method for the attachment of a vertebral bone connector that is used to fixate at least two vertebral bones wherein at least one bone distraction screw is placed into each of an upper most and a lower most of the fixated vertebral bones, the method comprising: 
 actuating bone distraction screws to position the bones in a desired spatial configuration relative to one another;    positioning at least one end of the vertebral bone connector onto a distraction screw so that a segment of the distraction screw transverses a slotted bore hole contained on an end of the connector, wherein the distraction screw segment is adapted to transverse the slotted bore hole from an inferior to superior direction and to reversibly capture and retain the connector in the seated position.    
   
   
       9 . An orthopedic implant adapted to fixate at least two skeletal bones of a human or animal subject, comprising: 
 a connector adapted to connect a plurality of bone anchors, wherein at least one bone anchor is adapted to be positioned into each of a skeletal bone;    a slotted bore hole that is contained within at least one end of the connector and is adapted to interact with at least a segment of a distraction screw so as to permit the connector to move relative to the underlying bone in a first plane while limiting movement in a second plane, wherein the slotted bore hole is has a vertical thickness less than that of the surrounding connector so as form a recess at a superior slot surface, wherein the recess provides a bearing surface against which an anchor may be forcibly seated to immobilize the connector relative to the underlying bone.