Frictional screw-rod connection having an indirect form-locking portion

Abstract

A spinal column implant for elastic stabilization of vertebrae, includes a pedicle screw and an elastic rod which is anchored in a frictional fashion in a receptacle of pedicle screws by means of a filling piece, and a clamping element. The frictional connection is supported additionally by an indirect form-fit portion.

What is claimed is: 
     
         1 . A spinal column implant comprising:
 an elastic connection element;   a plurality of bone screws, each bone screw having a screw head portion, one receptacle for the connection element, a filling piece, and a clamping element;   wherein the connection element is clamped by the clamping element in a space in the receptacle between the screw head portion and the filling piece; and   wherein in an area of the lower receptacle on the screw head portion and in an area of the upper receptacle on the filling piece, a contour of the space deviates from a contour of the connection element.   
     
     
         2 . A spinal column implant according to  claim 1 , wherein the contour of the space also deviates from the contour of the connection element around lateral portions of the receptacle between the screw head portion and the filling piece. 
     
     
         3 . A spinal column implant according to  claim 1 , wherein the deviations of the contour of the space are situated in one or more sections transverse to the longitudinal axis of the connection element, in the same plane or in different planes. 
     
     
         4 . A spinal column implant according to  claim 1 , wherein the deviations in the contour of the space are prominent or recessed. 
     
     
         5 . A spinal column implant according to  claim 2 , wherein the upper and lower deviations of the space are prominent and the lateral deviations are recessed. 
     
     
         6 . A spinal column implant according to  claim 1 , wherein the deviations in the contour of the space are rib-shaped or peg-shaped. 
     
     
         7 . A spinal column implant according to  claim 1 , wherein the connection element is a rod. 
     
     
         8 . A spinal column implant according to  claim 7 , wherein the rod is round. 
     
     
         9 . A spinal column implant according to  claim 1 , wherein the connection element comprises a plastic material. 
     
     
         10 . A spinal column implant according to  claim 9 , wherein the connection element is made of Polycarbonate Urethane. 
     
     
         11 . A spinal column implant according to  claim 1 , wherein the clamping element is a screw nut. 
     
     
         12 . A spinal column implant according to  claim 1 , wherein the filling piece comprises a receptacle for a holding instrument. 
     
     
         13 . A spinal column implant comprising:
 an elastic connection element comprising a plastic material;   a plurality of bone screws, each bone screw having a screw head portion, one receptacle for the connection element, a filling piece, and a clamping element;   wherein the connection element is clamped by the clamping element in a space in the receptacle between the screw head portion and the filling piece; and   wherein at least a portion of a contour of the space deviates from a contour of the connection element.   
     
     
         14 . A spinal column implant according to  claim 13 , wherein the deviations in the contour of the space are situated in one or more sections transverse to the longitudinal axis of the connection element, in the same plane or in different planes. 
     
     
         15 . A spinal column implant according to  claim 13 , wherein the deviations in the contour of the space are prominent or recessed. 
     
     
         16 . A spinal column implant according to  claim 13 , wherein the connection element is made of Polycarbonate Urethane. 
     
     
         17 . A spinal column implant comprising:
 a deformable connection element; and   a bone screw comprising a screw head portion, a receptacle configured to receive a section of the connection element, a filling piece, and a clamping element configured to clamp the section of the connection element in a space in the receptacle between the screw head portion and the filling piece;   wherein at least a portion of a contour of the space deviates from a contour of the connection element; and   wherein at least a portion of the section of the connection element deforms to substantially correspond to a contour of a corresponding portion of the space in the receptacle when the clamping element is clamped to provide a connection of the section of the connection element with the bone screw.   
     
     
         18 . A spinal column implant according to  claim 17 , wherein the connection element comprises Polycarbonate Urethane. 
     
     
         19 . A spinal column implant according to  claim 17 , wherein the section of the connection element deforms around an upper portion of the receptacle at the filling piece and a lower portion of the receptacle at the screw head portion. 
     
     
         20 . A spinal column implant according to  claim 17 , wherein the section of the connection element deforms around lateral portions of the receptacle between the screw head portion and the filling piece. 
     
     
         21 . A spinal column implant according to  claim 17 , wherein the section of the connection element deforms by any one of prominent deformation and recessed deformation. 
     
     
         22 . A spinal column implant according to  claim 17 , wherein a cross section of the connection element is any one of circular, square and triangular shaped. 
     
     
         23 . A spinal column implant according to  claim 1 , wherein the filling piece is laterally guided in the receptacle. 
     
     
         24 . A spinal column implant according to  claim 13 , wherein the filling piece is laterally guided in the receptacle. 
     
     
         25 . A spinal column implant according to  claim 17 , wherein the filling piece is laterally guided in the receptacle. 
     
     
         26 . A spinal column implant according to  claim 1 , wherein the clamping element clamps the connection element in a force-fit fashion. 
     
     
         27 . A spinal column implant according to  claim 13 , wherein the clamping element clamps the connection element in a force-fit fashion. 
     
     
         28 . A spinal column implant according to  claim 17 , wherein the clamping element clamps the connection element in a force-fit fashion.