Tower tool for minimally invasive surgery

Abstract

A rod reduction tool assembly includes an outer tube with outer tangs for engaging a bone anchor, an inner partially tubular pin support and a threaded cap mated to the outer tube and engaging the inner pin support.

What is claimed and desired to be secured by Letters Patent is as follows: 
     
         1 . In a medical implant holding tool having engagement structure at a lower end thereof operably mateable with opposed arms of an open receiver of a bone anchor, the receiver opposed arms defining a channel for receiving a longitudinal connecting member, the improvement comprising:
 a) an elongate outer holding tool with an upper tubular portion having a top surface and a first helical thread, the tubular portion terminating at a pair of opposed downwardly extending tangs located opposite the top surface, each tang having an aperture and the engagement structure for mating with one of the arms of the bone anchor receiver; and   b) a cap having a bottom surface and a second helical thread sized and shaped for mating engagement with the first helical thread of the outer holding tool, the cap bottom surface engageable with an elongate portion and wherein rotation of the cap with respect to the outer holding tool moves the elongate portion downwardly into a location against an outer surface of the bone anchor, thereby rotationally fixing the holding tool tangs with respect to the bone anchor.   
     
     
         2 . The improvement of  claim 1 , wherein the pin support upper portion has a cylindrical outer surface portion and the cap is slidingly received thereon. 
     
     
         3 . The improvement of  claim 2 , further comprising a deformable ring partially located in an annular recess formed in the cylindrical surface portion, the deformable ring located above the cap. 
     
     
         4 . The improvement of  claim 1 , wherein the tang apertures are in the form of axial through bores. 
     
     
         5 . The improvement of  claim 1 , wherein the outer holding tool tubular portion is integral with the downwardly extending tangs. 
     
     
         6 . The improvement of  claim 1 , wherein the inner pin support upper portion is fixed to the pair of opposed elongate pins. 
     
     
         7 . The improvement of  claim 1 , wherein each tang has a first surface and an opposed second surface, the first surface sized and shaped for engaging an inner curved surface of a receiver arm and the second surface sized and shaped for engaging an outer curved surface of the receiver arm, the first and second tangs rotatably mounted on and off of the receiver arm surfaces. 
     
     
         8 . The improvement of  claim 1 , further comprising an inner pin support received within the outer holding tool, the pin support having an upper portion connected to a pair of opposed elongate pins, each pin sized and shaped to extend through the aperture of one of the outer holding tool tangs. 
     
     
         9 . In a combination of a bone attachment structure having a receiver and a medical implant holding tool having receiver attachment structure at a lower end thereof operably mateable with the receiver; the improvement wherein:
 a) the receiver has two arms, each arm having an undercut first surface projecting downwardly toward a bottom thereof and a curved surface located directly above the undercut surface; and   b) the tool has an outer portion, an inner portion slidably received within the outer portion and a cap, the outer portion having structure in engagement with the receiver undercut surface, the inner portion having a pair of opposed pins, each pin extending through an aperture of the outer portion, the cap threadably connected to the outer portion and in abutment with the inner portion, and wherein rotation of the cap with respect to the outer portion causes the cap to press against and move the inner portion in a downward direction toward the receiver and thereby move the pair of opposed pins into engagement with the receiver arm curved surfaces.   
     
     
         10 . The improvement of  claim 9 , wherein each receiver arm has an inner surface located directly above a dual start guide and advancement structure and wherein the tool engages the inner surface. 
     
     
         11 . The improvement of  claim 10 , wherein the tool is rotatable on and off of the receiver in both a clockwise and a counterclockwise manner. 
     
     
         12 . In a medical implant holding tool having engagement structure at a lower end thereof operably mateable with opposed arms of an open receiver of a bone anchor, the receiver opposed arms defining a channel for receiving a longitudinal connecting member, the improvement comprising:
 a) an elongate outer holding tool with a tubular portion having a top surface and an inner cylindrical surface having a first helical thread, the tubular portion terminating at a pair of opposed downwardly extending tangs located opposite the top surface, each tang having an aperture and the engagement structure for mating with one of the arms of the bone anchor receiver;   b) an inner pin support received within the outer holding tool, the pin support having an upper portion connected to a pair of opposed elongate pins, each pin sized and shaped to extend through the aperture of one of the outer holding tool tangs; and   c) a cap having a bottom surface and a second helical thread sized and shaped for mating engagement with the first helical thread of the outer holding tool, the cap bottom surface engageable with the inner pin support upper portion and wherein rotation of the cap with respect to the outer holding tool moves the pins downwardly into a location against an outer surface of the bone anchor, thereby rotationally fixing the holding tool tangs with respect to the bone anchor.