Locking Device And Method Employing A Posted Member To Control Positioning Of A Stabilization Member Of A Bone Stabilization System

Abstract

A locking device and method are provided for a bone stabilization system which includes a bone anchor, a coupling mechanism and a stabilization member, wherein the coupling mechanism couples the stabilization member to the bone anchor. The locking device includes a seating member and a posted member. The seating member is operatively associated with the coupling mechanism for securing the stabilization member within the coupling mechanism, and is configured with an opening therein. The posted member, which includes an interface member and a post extending therefrom, is configured for disposition between the seating member and the stabilization member with the post extending therefrom being received into the opening in the seating member when the seating member is employed to secure the stabilization member within the coupling mechanism. The post is sized to engage and facilitate control of the stabilization member as the seating member operatively engages the coupling mechanism.

1 - 33 . (canceled) 
     
     
         34 . A surgical drive tool for inserting/extracting a locking device of a bone stabilization system including a bone anchor, a coupling mechanism, and a stabilization member, wherein the coupling mechanism is configured to couple the stabilization member to the bone anchor, and wherein the locking device comprises a seating member operatively associated with the coupling mechanism for securing the stabilization member within the coupling mechanism, the seating member being configured with at least one opening therein, and comprises a posted member including an interface member and at least one post extending therefrom, the posted member being configured for disposition between the seating member and the stabilization member with the at least one post extending from the interface member being received into the at least one opening of the seating member when the seating member is employed to secure the stabilization member within the coupling mechanism, and wherein the surgical drive tool comprises:
 a first component configured to operatively engage the seating member to facilitate positioning of the seating member within the coupling mechanism; and   a second component configured to operatively engage the at least one post of the posted member to facilitate maintaining the posted member fixed and in physical contact with the stabilization member as the first component is employed to secure the seating member within the coupling mechanism, thereby securing the stabilization member within the coupling mechanism between the posted member and the coupling mechanism.   
     
     
         35 . The surgical drive tool of  claim 34 , wherein the seating member comprises a threaded portion configured to threadably engage the coupling mechanism, and wherein the first component rotatably engages the seating member to facilitate threading of the seating member into the coupling mechanism, and the second component engages the at least one post of the posted member to maintain the posted member fixed and in physical contact with the stabilization member as the seating member is threaded into the coupling mechanism. 
     
     
         36 . The surgical drive tool of  claim 35 , wherein the first component comprises an outer shaft and the second component comprises an inner shaft, the outer shaft engaging a surgical tool receiving portion of the seating member, and the inner shaft engaging at least a portion of the at least one post of the posted member, the outer shaft being rotatable to facilitate the threaded engagement of the threaded portion of the seating member to the coupling mechanism. 
     
     
         37 . The surgical drive tool of  claim 36 , further comprising a locking mechanism for selectively locking the inner shaft and the outer shaft together, thereby forcing the inner shaft and outer shaft to turn together. 
     
     
         38 . The surgical drive tool of  claim 37 , wherein the locking mechanism comprises a gear and pawl apparatus, wherein with rotation of the outer shaft in a first direction, the pawl allows the gear to rotate, while rotation of the outer shaft in a second direction locks the pawl and gear and causes the inner shaft and outer shaft to turn together. 
     
     
         39 . The surgical drive tool of  claim 38 , wherein the at least one post comprises a post including a break-off post portion which is removed after the seating member is employed to secure the stabilization member within the coupling mechanism, wherein the outer shaft is employed to secure the seating member within the coupling mechanism by rotating the outer shaft in the first direction, and wherein the break-off post portion is removed by rotating the outer shaft in the second direction, causing the inner and outer shafts to turn together, thereby causing break-off of the break-off post portion, and wherein the post has a transverse cross-section comprising one of a circular cross-section, a triangular cross-section, a rectangular cross-section or a hexagonal cross-section, and wherein the inner shaft is configured to matably receive at least part of the break-off post portion. 
     
     
         40 . The surgical drive tool of  claim 37 , wherein the locking mechanism comprises a mating plate having at least one arm configured for selective placement through a first opening in a cap associated with the outer shaft, and a second opening in a disc associated with the inner shaft, wherein placement of the arm through the first opening and the second opening results in the inner shaft and the outer shaft turning together. 
     
     
         41 . The surgical drive tool of  claim 37 , wherein selective locking of the inner shaft and the outer shaft facilitates break-off of a portion of the at least one post along a circumferential break-off line provided in the at least one post. 
     
     
         42 . A method for stabilizing a spinal column, the method comprising
 providing a bone stabilization system comprising a bone anchor, a stabilization member, a coupling mechanism, and a locking device, wherein the coupling mechanism is configured to couple the stabilization member to the bone anchor, and the locking device is operatively associated with the coupling mechanism, and wherein the locking device further comprises a seating member configured to threadably engage the coupling mechanism and a posted member configured to control the stabilization member as the seating member threadably engages the coupling mechanism, the posted member comprising an interface member and at least one post extending therefrom, and wherein the seating member comprises at least one opening therein;   attaching the bone anchor with the coupling mechanism secured thereto to a vertebra of the spinal column;   positioning the stabilization member in the coupling mechanism;   positioning the posted member with the at least one post thereof within the at least one opening of the seating member, and threading the seating member into the coupling mechanism while holding the at least one post of the posted member fixed and in physical contact with the stabilization member, thereby maintaining control of the stabilization member as the seating member engages the coupling mechanism; and   continuing to threadably advance the seating member into the coupling mechanism, thereby causing the posted member to become fixed between the seating member and the stabilization member, and securing the stabilization member between the posted member and the coupling mechanism.   
     
     
         43 . The method of  claim 42 , further comprising employing a surgical drive tool for performing the threading of the seating member into the coupling mechanism and the holding of the at least one post of the posted member fixed and in physical contact with the stabilization member. 
     
     
         44 . The method of  claim 43 , wherein the surgical drive tool includes a first component configured to operatively engage the seating member to facilitate the threading of the seating member into the coupling mechanism and a second component configured to operatively engage the at least one post of the posted member to facilitate the holding of the at least one post of the posted member fixed and in physical contact with the stabilization member. 
     
     
         45 . The method of  claim 42 , further comprising breaking off at least one of a portion of the seating member after threadable engagement of the seating member within the coupling mechanism or a portion of the at least one post of the posted member. 
     
     
         46 . The method of  claim 45 , wherein the providing further comprises providing the seating member with a circumferential break-off line extending around the perimeter thereof, and wherein the continuing further comprises continuing to advance the seating member until break off of a break-off portion of the seating member along the circumferential break-off line thereof. 
     
     
         47 . The method of  claim 46 , wherein the providing further comprises providing the at least one post with a circumferential break-off line extending around the perimeter thereof, and wherein the method further comprises breaking off a portion of the at least one post after threadably advancing the seating member into the coupling mechanism and causing the posted member to become fixedly positioned between the seating member and the stabilization member.