Osteosynthetic Implant With An Embedded Hinge Joint

Abstract

An osteosynthesis implant includes at least one coupling in the form of a swivel joint. Each swivel joint includes at least one planar or annular swivel element and two connecting arms that define a pivot axis. The coupling permits rotation about each pivot axis. The implant and coupling may be formed of unitary construction, or a separate coupling may be connectable to the implant. The coupling may receive a bone fastener such as a bone screw, or may be used in applications that require the coupling to directly support portions of the body such as spinal features.

1 . (canceled) 
     
     
         2 . A bone fixation system, comprising:
 a first coupler for coupling a bone screw to a longitudinal support;   a first screw guiding member including a first screw receiving hole defining a first screw axis, the first screw receiving hole being sized so that the first bone screw may be inserted therein only along the first screw axis;   first and second pivot arms extending radially outward from the first screw guiding member along a first pivot axis to connect the first screw guiding member to the first coupler so that the first screw guiding member can pivot relative to the first coupler about the first pivot axis to pivot the first screw axis relative to the first coupler;   a second coupler for coupling a second bone screw to the longitudinal support;   a second screw guiding member including a second screw receiving hole defining a second screw axis, the second screw receiving hole being sized so that the second bone screw may be inserted therein only along the second screw axis; and   third and fourth pivot arms extending radially outward from the second screw guiding member along a second pivot axis to connect the second screw guiding member to the second coupler so that the second screw guiding member can pivot relative to the second coupler about the second pivot axis to pivot the second screw axis relative to the second coupler.   
     
     
         3 . The system of  claim 2 , wherein the longitudinal support is a rod, a longitudinal axis of the rod extending substantially perpendicularly to the first and second screw axes. 
     
     
         4 . The system of  claim 2 , wherein the first coupler includes a first channel sized and shaped to receive the longitudinal support therein. 
     
     
         5 . The system of  claim 4 , further comprising a fastener in threaded engagement with the first coupler to lock the longitudinal support within the first channel. 
     
     
         6 . The system of  claim 2 , wherein the first and second bone screws are pedicle screws and wherein the longitudinal support is a spinal support rod. 
     
     
         7 . The system of  claim 2 , wherein the first screw receiving hole and a head of the first bone screw are structured to create an angularly stable connection between the first bone screw and the first screw guiding member to lock the first bone screw at the first screw axis. 
     
     
         8 . The system of  claim 2 , wherein first screw guiding member includes an outer ring coupled to the first and second pivot arms and an inner ring coupled to the outer ring by fourth and fifth pivot arms extending along a third pivot axis so that the inner ring can pivot about the third pivot axis relative to the outer ring. 
     
     
         9 . The system of  claim 8 , wherein the third pivot axis is substantially perpendicular to the first pivot axis. 
     
     
         10 . A method for treating bone comprising the steps of:
 inserting to a first target location within a living body a first coupler and a first screw guiding member including a first screw receiving hole defining a first screw axis, wherein first and second pivot arms extend radially outward from the first screw guiding member along a first pivot axis to connect the first screw guiding member to the first coupler so that the first screw guiding member can pivot relative to the first coupler about the first pivot axis;   inserting a first bone screw through the first screw receiving hole along the first screw axis;   locking the first bone screw to the first screw guiding member to create an angularly stable connection therebetween;   pivoting the first screw guiding member to a desired angle relative to the first coupler and inserting the first bone screw into a first target portion of bone along a desired axis;   coupling the first coupler to a longitudinal support;   inserting to a second target location within the living body a second coupler and a second screw guiding member including a second screw receiving hole defining a second screw axis, wherein third and fourth pivot arms extend radially outward from the second screw guiding member along a second pivot axis to connect the second screw guiding member to the second coupler so that the second screw guiding member can pivot relative to the second coupler about the second pivot axis;   inserting a second bone screw through the second screw receiving hole along the second screw axis;   locking the second bone screw to the second screw guiding member to create an angularly stable connection therebetween;   pivoting the second screw guiding member to a desired angle relative to the second coupler and inserting the second bone screw into a second target portion of bone along a desired axis; and   coupling the second coupler to the longitudinal support.   
     
     
         11 . The method of  claim 10 , wherein the step of coupling the first coupler to the longitudinal support comprises inserting the rod into a channel of the first coupler and tightening a threaded nut over the channel. 
     
     
         12 . The method of  claim 11 , wherein the first and second bone screws are pedicle screws and wherein the longitudinal support is a spinal support rod. 
     
     
         13 . The method of  claim 10 , further comprising:
 locking a head of the first bone screw in the screw guiding member to create an angularly stable connection between the first bone screw and the first screw guiding member with the first bone screw locked at the first screw axis.   
     
     
         14 . The method of  claim 10 , wherein first screw guiding member includes an outer ring coupled to the first and second pivot arms and an inner ring coupled to the outer ring by fourth and fifth pivot arms extending along a third pivot axis, the method further comprising pivoting the inner ring can pivot about the third pivot axis relative to the outer ring.