Systems and methods for manipulating and/or installing a pedicle screw

Abstract

A nested dilation tube assembly for enabling implantation of a spinal screw assembly into a vertebrae is provided. The dilation tube assembly includes a plurality of dilation tubes. Each dilation tube includes an elongated cylindrical shaft with an outer diameter slightly larger than a preceding dilation tube. After being inserting into a body, the plurality of dilation tubes form a nested, concentric assembly enabling an opening placed in the spinal area and/or vertebrae to be enlarged up to the outer diameter of a last dilation tube. The inner dilation tubes are capable of being removed from outer dilation tubes such that the inner diameter of an inner most remaining dilation tube forms a space for receiving instruments and/or assemblies.

We Claim: 
     
         1 . A nested dilation tube assembly for opening a surgical site, the nested dilation tube assembly comprising:
 a plurality of dilation tubes having at least an inner dilation tube, a medial dilation tube and an outer dilation tube, each of the plurality of tubes have an elongated cylindrical shaft with a bore, each of the elongated cylindrical shaft having an outer diameter, wherein the outer diameter of the outer dilation tube is larger than the outer diameter of the medial dilation tube, and the outer diameter of the medial dilation tube is larger than the outer diameter of the inner dilation tube so as to allow the plurality of dilation tubes to form a nested, concentric assembly enabling an opening to be enlarged up to the outer diameter of the outer dilation tube.   
     
     
         2 . The nested dilation tube assembly as set forth in  claim 1 , wherein the inner dilation tube is configured to be removed from the outer dilation tube so as to provide a space for receiving instruments and/or assemblies for implantation into the surgical site. 
     
     
         3 . The nested dilation tube assembly of  claim 1 , further including a wire, the wire configured to slide within the bore of the inner dilation tube so as to form an initial opening, wherein each of the plurality of dilation tubes may be sequentially inserted into the surgical site so as to progressively enlarge the surgical site. 
     
     
         4 . The nested dilation tube assembly of  claim 1 , wherein the inner dilation tube is longer than the medial dilation tube, and the medial dilation tube is longer than the outer dilation tube. 
     
     
         5 . The nested dilation tube assembly of  claim 1 , wherein the inner dilation tube includes a first lip disposed on a proximal end of the inner dilation tube. 
     
     
         6 . The nested dilation tube assembly of  claim 5 , wherein the first lip is a flared protrusion. 
     
     
         7 . The nested dilation tube assembly of  claim 1 , wherein the medial dilation tube includes a second lip disposed on a proximal end of the medial dilation tube. 
     
     
         8 . The nested dilation tube assembly of  claim 7 , wherein the second lip is a flared protrusion. 
     
     
         9 . The nested dilation tube assembly of  claim 1 , wherein each of the plurality of dilation tubes a pointed head disposed on a distal end of each of the elongated cylindrical shaft the a respective one of the plurality of dilation tubes. 
     
     
         10 . The nested dilation tube assembly as set forth in  claim 9 , wherein the pointed head of the inner dilation tube is narrower than the pointed head of the medial dilation tube, and the pointed head of the medial dilation tube is narrower than the pointed head of the outer dilation tube. 
     
     
         11 . A method of making a surgical opening in a surgical site, the method comprising the steps of:
 providing a plurality of dilation tubes having at least an inner dilation tube, a medial dilation tube and an outer dilation tube, each of the plurality of tubes have an elongated cylindrical shaft with a bore, each of the elongated cylindrical shaft having an outer diameter, wherein the outer diameter of the outer dilation tube is larger than the outer diameter of the medial dilation tube, and the outer diameter of the medial dilation tube is larger than the outer diameter of the inner dilation tube;   providing a wire, the wire disposed within the inner dilation tube;   inserting the wire into the surgical site;   inserting the inner dilation tube into the surgical site;   sliding the medial dilation tube over the inner dilation tube so as to enlarge the surgical site;   sliding the outer dilation tube over the medial dilation tube so as to enlarge the surgical site, wherein the inner dilation tube, the medial dilation tube and the outer dilation tube form a nested, concentric assembly.   
     
     
         12 . The method as set forth in  claim 11 , further including the following steps in sequence:
 removing the wire from the surgical site;   removing the inner dilation tube from the surgical site; and   removing the medial dilation tube from the surgical site.   
     
     
         13 . The method as set forth in  claim 12 , further including the step of inserting a screw into the surgical site within the bore of the elongated cylindrical shaft of the outer dilation tube.