Anchors for vertebral body

Abstract

Implantable devices for dynamic interconnection between bones, and especially between vertebrae. Some devices include tethering heads that are independent of the bone connecting member (fastener, plate, hook, loop). The devices provide for various types of manipulation of a flexible connection such as a tether, such as by providing an aperture through which the flexible connection is passed and guided, or a post to which a loop of the flexible connection can be attached, or a groove in which a loop of the flexible connection can be placed.

What is claimed is: 
     
         1 . A member for tethered connection to a bone, comprising:
 a bone connecting member adapted and configured for connection with a bone; and   a tethering head separate from said bone connecting member, said tethering head including a passageway being adapted and configured to accept therein a flexible tether, said tethering head having a bone contacting surface; said tethering head being adapted and configured for coupling to said bone connecting member;   wherein connection of said bone connecting member to a bone places the bone contacting surface in contact with said bone.   
     
     
         2 . The member of  claim 1 , wherein said tethering head has an outer peripheral surface and an ear projecting from the outer surface, and said passageway extends through the ear. 
     
     
         3 . The member of  claim 2 , wherein said ear is a first ear and the passageway is a first through passageway, and which further includes a second ear projecting from the outer surface, the second ear including a second through passageway adapted and configured to accept therein a flexible tether. 
     
     
         4 . The member of  claim 3 , wherein the first ear and second ear are on opposing sides of said tethering head. 
     
     
         5 . The member of  claim 3 , wherein the first and second passageways are substantially parallel. 
     
     
         6 . The member of  claim 1 , wherein said tethering head includes a through aperture adapted and configured to receive therethrough said bone connecting member. 
     
     
         7 . The member of  claim 6 , wherein coupling of said bone connecting member and said tethering head aligns in opposition opposing surfaces of said bone contacting member and said tethering head, and connection of said bone connecting member to the vertebra places the contacting surfaces in compression. 
     
     
         8 . The member of  claim 1 , wherein said tethering head has an outer periphery and the passageway is a groove extending around the periphery of said tethering head, the groove being adapted and configured to contain the flexible connector. 
     
     
         9 . The member of  claim 8 , wherein the flexible connector has a diameter, and the width of the groove is greater than the diameter, and the depth of the groove is greater than the diameter. 
     
     
         10 . The member of  claim 8 , wherein said tethering head includes a pair of separated grooves each extending around the periphery of said tethering head, each groove being adapted and configured to contain the flexible connector. 
     
     
         11 . The member of  claim 10 , wherein said shaft has an axis, and each groove is substantially perpendicular to the axis. 
     
     
         12 . The member of  claim 10 , wherein each groove is substantially parallel to the other groove. 
     
     
         13 . A member for tethered connection to a bone, comprising:
 a bone connecting member adapted and configured for connection with a bone;   a tethering head separate from said bone connecting member, said tethering head having a top surface and including a passageway on the top surface, the passageway being adapted and configured to accept therein a flexible tether, each said passageway having an entrance and an exit, the passageway being accessible from the top of said tethering head; and   a cover adapted and configured to cover the top surface and the passageway   
     
     
         14 . The member of  claim 13 , wherein said cover and said bone connecting member are integral. 
     
     
         15 . The member of  claim 13 , wherein said bone connecting member includes a threaded shaft and said tethering head includes an aperture extending from the top surface of said tethering head through the bone contacting surface, the aperture being sized to accept therethrough the shaft. 
     
     
         16 . The member of  claim 13 , wherein said bone connecting member includes an anchoring head and said tethering head includes a contacting surface, and connection of said bone connecting member to the vertebra places the anchoring head in compression against the contacting surface. 
     
     
         17 . The member of  claim 13 , wherein said tethering head includes a bone contacting surface, the bone contacting surface being in contact with the vertebra when said bone connecting member is connected to a vertebra. 
     
     
         18 . The member of  claim 13 , wherein the entrance and exit are located proximate to each other such that the flexible tether loops from the entrance to the exit around a portion of said tethering head. 
     
     
         19 . The member of  claim 13 , wherein the exit and entrance define a post therebetween, said post includes smoothly contouring surface adapted and configured to permit sliding movement of a tether wrapped around the post without abrasively damaging the tether. 
     
     
         20 . The member of  claim 13 , wherein said passageway is a first passageway, and which further includes a second passageway on the top surface, the second passageway being adapted and configured to accept therein a flexible tether. 
     
     
         21 . The member of  claim 20 , wherein the first and second passageways are located on opposite sides of said tethering head. 
     
     
         22 . The member of  claim 21 , wherein each of the first and second passageways are open to the top surface of said tethering head.