Modular vertebral stabilizer

Abstract

A stabilizer device ( 1 ) for the spinal column, comprising first engagement means ( 4 ) and second engagement means ( 5 ), which are adapted to be connected to each other by a rod-like element ( 8 ), the first and second engagement means ( 4, 5 ) being adapted to be fitted on first and second pedicle screws ( 2, 3 ), which are adapted to be in turn inserted in two adjacent vertebrae, the first and second engagement means ( 4, 5 ) being fixable on the pedicle screws ( 2, 3 ); the first and second engagement means ( 4, 5 ) accommodate bearing means ( 20 ), which are adapted to rotate within the first and second engagement means ( 4, 5 ) and to be fitted on the pedicle screws ( 2, 3 ), in order to allow the fitting of the first and second engagement means ( 4, 5 ) on the pedicle screws ( 2, 3 ).

1 . A stabilizer device for the spinal column, comprising first engagement means and second engagement means, which are adapted to be connected to each other by a rod-like element, said first and second engagement means being adapted to be fitted on first and second pedicle screws, which are adapted to be in turn inserted in two adjacent vertebrae, said first and second engagement means being fixable on said pedicle screws, characterized in that said first and second engagement means accommodate bearing means, which are adapted to rotate within said first and second engagement means and to be fitted on said pedicle screws, in order to allow the fitting of said first and second engagement means on said pedicle screws. 
     
     
         2 . The device according to  claim 1 , characterized in that said first and second engagement means are connected to each other through a rigid rod-like element. 
     
     
         3 . The device according to  claim 1 , characterized in that said first and second engagement means are connected to each other through a flexible rod-like element. 
     
     
         4 . The device according to  claim 1 , characterized in that said first and second engagement means comprise disk-like bodies provided with at least one protruding portion that is adapted to accommodate said rod-like element. 
     
     
         5 . The device according to  claim 1 , characterized in that said pedicle screws are headless screws. 
     
     
         6 . The device according to  claim 1 , characterized in that at least one of said first and second disk-like elements is provided with a second protruding portion, which is arranged diametrically opposite the first protruding portion and is adapted to accommodate a further rod-like element. 
     
     
         7 . The device according to  claim 1 , characterized in that said first and second disk-like elements are coupled to each other by said rod-like element and by a cord that is adapted to be fastened around said rod-like element that passes within the respective protruding portions of said first and second disk-like elements. 
     
     
         8 . The device according to  claim 1 , characterized in that said flexible rod-like element is provided with two mutually opposite lateral recesses, which are adapted to accommodate said cord suitable to be fastened around said rod-like element. 
     
     
         9 . The device according to  claim 1 , characterized in that cord is provided, at one end, with a plurality of teeth for fastening within accommodation means provided at the opposite end, said accommodation means being adapted to allow the fastening within them of said end provided with teeth, so as to fasten said cord around said rod-like element. 
     
     
         10 . The device according to  claim 1 , characterized in that said protruding portions of said first and second disk-like elements are provided with at least one hole which is adapted to allow either the passage of said cord or the insertion of a threaded grub which is adapted to allow the locking of said rod-like element within said protruding portions. 
     
     
         11 . An element for fixing to a pedicle screw, comprising a disk-like body adapted to be fitted on the head of said pedicle screw, characterized in that said, disk-like body accommodates bearing means which are adapted to rotate within said body in all directions, in order to allow the fitting of said body on said pedicle screw. 
     
     
         12 . The fixing element according to  claim 11 , characterized in that said body is provided with at least one protruding portion which has a receptacle for accommodating a rod-like element adapted to allow connection to a further fixing body.