Spinal fixation tool set and method

Abstract

The disclosure describes systems and methods for implanting bone screws and a rod for spinal surgery. In one embodiment, a system may include a guide tool having an elongate body that includes a proximal end, a distal end, a channel extending longitudinally between the proximal end and the distal end and having a channel opening at the proximal end thereof. The elongate body may include an engagement structure having first and second projections disposed at the distal end. The system may also include a bone screw assembly including first and second tool engagement structures disposed thereon. Each of the first and second projections is sized and shaped to be received in a corresponding one of the first and second tool engagement structures of the bone screw assembly, for releasable attachment thereto. A method utilizing the system allows a surgeon to percutaneously implant bone screws and the rod in the patient.

What is claimed is: 
     
         1 . A system for affixing a fixation rod to a spine of a patient, comprising:
 a guide tool comprising:
 an elongate body including: a proximal end, a distal end, a channel extending longitudinally between the proximal end and the distal end and having a channel opening at the proximal end thereof, and 
 an engagement structure at the distal end of the elongate body, the engagement structure having a first projection disposed thereon and extending radially inward therefrom, and a second projection disposed opposed to the first projection and extending radially inward, and 
   a bone screw assembly comprising a first tool engagement structure disposed thereon and a second tool engagement structure disposed opposed to the first tool engagement structure,   wherein each of the first and second projections is sized and shaped to be received in a corresponding one of the first and second tool engagement structures of the bone screw assembly, for releasable attachment thereto.   
     
     
         2 . The system of  claim 1 , wherein the first and second projections include a first proximally projecting lip and a second proximally projecting lip, respectively, and the first tool engagement structure and the second tool engagement structure include a first proximally projecting inner recess and a second proximally projecting inner recess therein, respectively. 
     
     
         3 . The system of  claim 2 , wherein each of the first and second proximally projecting lips is sized and shaped to be received in a corresponding one of the first and second proximally projecting inner recesses in the bone screw assembly. 
     
     
         4 . The system of  claim 1 , wherein the elongate body comprises a handle portion disposed at the proximal end, and a first elongate leg and an opposite, second elongate leg each extending distally from the handle portion, and a longitudinal through-slot formed between the first and second elongate legs. 
     
     
         5 . The system of  claim 4 , wherein each of the first and second projections extends radially inwardly from a corresponding inner surface of the first and second elongate legs into the channel. 
     
     
         6 . The system of  claim 4 , wherein the through-slot is sized and shaped to allow manual flexing of the first and second elongate legs to increase a distance between the first and second projections during insertion of the bone screw assembly into the guide tool. 
     
     
         7 . The system of  claim 1 , wherein a diameter of the channel is variable through the elongate body. 
     
     
         8 . The system of  claim 1 , wherein the guide tool further comprises a lateral channel opening extending through an outer surface of the guide tool and along at least a portion of the overall length of the elongate body, the lateral channel opening sized and shaped for side loading and receiving of at least a portion of a spinal rod. 
     
     
         9 . The system of  claim 1 , wherein the bone screw assembly comprises: a head including a central bore defining a rod-receiving channel, and a shank configured to be coupled to the head. 
     
     
         10 . The system of  claim 9 , wherein the bone screw assembly further comprises: a retaining structure sized and shaped to be inserted into the head, and a fastener configured to be rotatably inserted onto an upper end of the shank and to secure the retaining structure within the head. 
     
     
         11 . The system of  claim 1 , further comprising a driving tool receivable in the channel of the guide tool and configured to attach to the bone screw assembly for rotating and driving the bone screw assembly into bone. 
     
     
         12 . The system of  claim 11 , wherein the guide tool further includes an outer guide and advancement structure, and
 the driving tool includes: a stem, a driving structure disposed at a proximal end of the stem, and a fastener configured to couple the stem to the driving structure, wherein the fastener is freely rotatable with respect to the stem and includes an inner guide and advancement structure mateable with the outer guide and advancement structure of the guide tool.   
     
     
         13 . The tool set of  claim 12 , wherein a distal end of the stem includes a socket for receiving an upper portion of the bone screw assembly. 
     
     
         14 . A system for affixing a fixation rod to a spine of a patient, comprising:
 a guide tool comprising:
 an elongate body including:
 a proximal end, a distal end, a channel extending longitudinally between the proximal end and the distal end and having a channel opening at the proximal end thereof, 
 a handle portion disposed at the proximal end, and a first elongate leg and an opposite, second elongate leg each extending distally from the handle portion, and 
 a first projection disposed on the first elongate leg and extends radially inwardly into the channel, and a second projection disposed on the second elongate leg and extends radially inwardly into the channel, and 
 
   a bone screw assembly comprising a first tool engagement structure disposed thereon and a second tool engagement structure disposed opposed to the first tool engagement structure,   wherein the first and the second elongate legs are shaped to allow manual flexing of the first and the second elongate legs and a snap-on cooperation between each of the first and second projections and a corresponding one of the first and second tool engagement structures in the bone screw assembly.   
     
     
         15 . The system of  claim 14 , wherein the bone screw assembly comprises: a head including a central bore defining a rod-receiving channel, a shank configured to be coupled to the head, a retaining structure sized and shaped to be inserted into the head, and a fastener configured to be rotatably inserted onto an upper end of the shank and to secure the retaining structure within the head. 
     
     
         16 . The system of  claim 14 , wherein the first and second projections include a first proximally projecting lip and a second proximally projecting lip, respectively, and the first tool engagement structure and the second tool engagement structure include a first proximally projecting inner recess and a second proximally projecting inner recess therein, respectively, and wherein each of the first and second proximally projecting lips is sized and shaped to be received in a corresponding one of the first and second proximally projecting inner recesses in the bone screw assembly. 
     
     
         17 . The system of  claim 14 , further comprising a driving tool receivable in the channel of the guide tool and configured to attach to the bone screw assembly for rotating and driving the bone screw assembly into bone. 
     
     
         18 . A method for implanting a bone screw assembly in a patient, the method comprising:
 providing a guide tool comprising:
 an elongate body including: a proximal end, a distal end, a channel extending longitudinally between the proximal end and the distal end and having a channel opening at the proximal end thereof, and 
 an engagement structure at the distal end of the elongate body, the engagement structure having a first projection disposed thereon and extending radially inward therefrom, and a second projection disposed opposed to the first projection and extending radially inward, 
   providing a bone screw assembly comprising a head and a shank configured to be coupled to the head, the head including a first tool engagement structure disposed on an outer surface thereof and a second tool engagement structure disposed opposed to the first tool engagement structure on the outer surface; and   sliding the guide tool relative to an outer surface of the head until each of the first and second projections is received into a corresponding one of the first and second tool engagement structures of the head.   
     
     
         19 . The method of  claim 18 , further comprising pulling the guide tool relative to the outer surface of the head after the sliding and causing a proximally projecting lip of the first projection to enter a corresponding proximally projecting inner recess of the first tool engagement structure. 
     
     
         20 . The method of  claim 18 , wherein the elongate body further comprises a handle portion disposed at the proximal end, and a first elongate leg and an opposite, second elongate leg each extending distally from the handle portion, and
 wherein the method further comprises flexing the first and second elongate legs to increase a distance between the first and second projections before the sliding.