Bone screw retaining and removal system

Abstract

A bone screw retention system is provided for a plate which defines a plurality of transversely extending bores that are configured to receive a hone screw for engaging the plate to the cervical spine. One or more retention members, having an elliptical, arcuate, straight, or other shape, can be positioned therein a cavity of the plate such that portions of the retention member(s) extend into a portion of an upper region of each bore to retain a bone screw therein. A bone screw removal device is provided, having at least one tongue member configured to selectively displace the one or more retention members to allow the bone screw to be removed from the respective bore.

1 - 25 . (canceled) 
     
     
         26 . A bone screw removal device for removing a bone screw from a plate, wherein the bone screw is retained in place by at least one elastically deformable retention member covering at least a portion of a head of the bone screw, the bone screw removal device comprising:
 an inner tubular sleeve having an outer diameter and defining a conduit extending from an upper end to a lower end of the inner sleeve, wherein the inner sleeve has at least one resilient tongue member comprising at least one protrusion extending outwardly from the lower end of the inner sleeve; and   an outer tubular sleeve having an inner diameter and defining at least one notch in a lower end of the outer sleeve for complementarily receiving the at least one protrusion of the inner sleeve;   wherein the inner diameter of the outer sleeve is greater than the outer diameter of the inner sleeve such that the inner sleeve is insertable into the outer sleeve, wherein when the inner sleeve is inserted into the outer sleeve, the at least one tongue member is movable about and between a first compressed position, in which the at least one protrusion of the at least one tongue member is resiliently biased inwardly toward a longitudinal axis of the conduit of the inner sleeve, and a second relaxed position, in which at least a portion of the at least one protrusion of the at least one tongue member of the inner sleeve is complementarity received therein the at least one notch of the outer sleeve, and wherein in the second relaxed position, at least a portion of the at least one protrusion engages a portion of the retention member and urges the retention member away from the head of the bone screw.   
     
     
         27 . The bone screw removal device of  claim 26 , wherein in the second relaxed position, the at least one protrusion of the at least one tongue member engages a portion of an outer edge of the at least one retention member. 
     
     
         28 . The bone screw removal device of  claim 26 , wherein in the second relaxed position, the at least one protrusion of the at least one tongue member engages an inner edge the at least one retention member. 
     
     
         29 . The bone screw removal device of  claim 26 , wherein the at least one resilient tongue member comprises a pair of resilient tongue members. 
     
     
         30 . The bone screw removal device of  claim 26 , wherein the at least one resilient tongue members comprises a plurality of resilient tongue members. 
     
     
         31 . The bone screw removal device of  claim 30 , wherein the at least one retention member comprises a plurality of retention members and wherein the number of resilient tongue members is equal to the number of retention members. 
     
     
         32 . The bone screw removal device of  claim 26 , wherein the at least one resilient tongue member has a spring constant greater than a spring constant of the at least one retaining member. 
     
     
         33 . The bone screw removal device of  claim 26 , further comprising a removal tool, wherein a portion of a distal end of the removal tool is configured to operatively engage the head of the bone screw. 
     
     
         34 . The bone screw removal device of  claim 26 , further comprising a removal tool, wherein a portion of a distal end of the removal tool is configured to engage at least a portion of the at least one protrusion of the at least one resilient tongue members, thereby urging the protrusion outwardly away from the longitudinal axis of the conduit. 
     
     
         35 . The bone screw removal device of  claim 26 , wherein the at least one protrusion of the at least one resilient tongue member is configured to be in opposition to the at least one retention member. 
     
     
         36 . The bone screw removal device of  claim 26 , wherein the diameter of the conduit of the inner sleeve member is greater than the diameter of the head of the bone screw. 
     
     
         37 . The bone screw removal device of  claim 26 , wherein, in the second relaxed position, the at least one protrusion of the at least one tongue member engages portions of the at least one retention member thereby medially biasing portions of the at least one retention member away from the longitudinal axis of the conduit. 
     
     
         38 . The bone screw removal device of  claim 26 , wherein, in the second relaxed position, an outer surface of the at least one protrusion of the at least one tongue member is substantially co-planar with an exterior surface of the outer sleeve proximate the at least one notch. 
     
     
         38 . The bone screw removal device of  claim 26 , wherein at least one longitudinal guide slot is defined in a portion of a body of the inner sleeve, wherein the at least one longitudinal guide slot is substantially parallel to the longitudinal axis of the conduit, and wherein the at least one longitudinal guide slot extends longitudinally for a predetermined length along the body of the inner sleeve. 
     
     
         39 . The bone screw removal device of  claim 38 , wherein the at least one longitudinal guide slot comprises a plurality of longitudinal guide slots. 
     
     
         39 . The bone screw removal device of  claim 38 , wherein the outer sleeve comprises at least one longitudinal projection that extends inwardly from an inner wall of the outer sleeve, wherein the length of the at least one projection is less than the length of the at least one longitudinal guide slot, and wherein the at least one projection is configured to be received therein the at least one guide slot of the inner sleeve. 
     
     
         40 . A method of removing a bone screw from a plate, wherein the bone screw is retained in place by at least one elastically deformable retention member covering at least a portion of a head of the bone screw, the method comprising:
 providing a bone screw removal device comprising:
 an inner tubular sleeve having an outer diameter and defining a conduit extending from an upper end to a lower end of the inner sleeve, wherein the inner sleeve has at least one resilient tongue member comprising at least one protrusion extending outwardly from the lower end of the inner sleeve; and 
 an outer tubular sleeve having an inner diameter and defining at least one notch in a lower end of the outer sleeve for complementarily receiving the at least one protrusion of the inner sleeve; 
 wherein the inner diameter of the outer sleeve is greater than the outer diameter of the inner sleeve such that the inner sleeve is insertable into the outer sleeve, wherein when the inner sleeve is inserted into the outer sleeve, the at least one tongue member is movable about and between a first compressed position, in which the at least one protrusion of the at least one tongue member is resiliently biased inwardly toward a longitudinal axis of the conduit of the inner sleeve, and a second relaxed position, in which the at least one protrusion of the at least one tongue member of the inner sleeve is complementarity received therein the at least one notch of the outer sleeve; 
   positioning the lower end of the outer sleeve on a shoulder of the bone screw such that the at least one notch is positioned over a portion of the retention member;   moving the inner sleeve so that the at least one tongue member is biased from the first compressed position to the second relaxed position, wherein in the second relaxed position, at least a portion of the at least one protrusion engages a portion of the retention member and urges the retention member away from the head of the bone screw;   inserting a removal tool through the conduit of the inner sleeve to operatively engage the head of the bone screw; and   removing the bone screw.