Active bone screw

Abstract

A bone screw includes a head portion and shank portion. The shank portion includes a regularly outwardly expanding threaded portion.

1 - 28 . (canceled) 
     
     
         29 . A method of inserting a bone screw into a bone by:
 threading a screw into a bone and forming a complimentary threaded socket in the bone; and   expanding a thread of the screw into the threaded socket as the threaded socket expands with wear over time.   
     
     
         30 . A method of maintaining a bone screw in a socket formed by the screw in a bone by expanding the thread of the screw into complimentary threads of the socket as the socket wears away over time. 
     
     
         31 . A method of expanding a thread of a screw. 
     
     
         32 . A method of inserting a bone screw into a bone by:
 Forming a socket in a bone and inserting a bone screw shank portion into the socket, while maintaining a radially expandable threaded portion of the screw shank portion in a compressed condition.   
     
     
         33 . The method of  claim 32  further including the steps of cutting a helical recess in the socket during said forming step and expanding the threaded portion into the helical recess as the shank portion is inserted into the socket. 
     
     
         34 . The method of  claim 33  further includes the step of expanding the thread portion into the helical recess as the helical recess wears over time. 
     
     
         35 . The method as set forth in  claim 33  wherein said cutting step is further defined as cutting the helical recess in the socket with an edge of the thread. 
     
     
         36 . The method as set forth in  claim 32  wherein said forming step is further defined as forming the socket with a diameter greater than major diameter of the bone screw shank portion and expanding the radially expandable threaded portion to engage and grip a wall of the socket. 
     
     
         37 . The method of  claim 36  wherein said expanding step is further defined as expanding the thread portion as the shaft portion is inserted into the socket. 
     
     
         38 . The method of  claim 36  wherein said expanding step is further defined as expanding the thread portion after the shaft portion is inserted into the socket. 
     
     
         39 . A method of inducing bone remodeling by applying a controlled force on a wall of a socket in a bone and creating a stress condition favorable for remodeling of the wall of the bone in the socket. 
     
     
         40 . A method as set forth in  claim 39  wherein said applying step is defined as radially outwardly expanding a threaded portion of a screw shank within the socket. 
     
     
         41 . A method of gaining and maintaining better pull out strength of a bone screw from a socket in a bone by applying a controlled force on a wall of a socket in a bone and creating a stress condition favorable for remodeling of the wall of the bone in the socket. 
     
     
         42 . A method of inducing intervertebral bone remodeling by applying a controlled force from an interbody fusion system against opposing vertebral surfaces. 
     
     
         43 . A method as set forth in  claim 42  wherein said applying step is further defined as outwardly expanding a threaded portion from a body of the interbody fusion system. 
     
     
         44 - 47 . (canceled)