Methods and devices for minimally invasive spinal fixation element placement

Abstract

Minimally invasive methods and devices for introducing a spinal fixation element into a surgical site in a patient's spinal column are provided. In general, the method involves advancing a spinal fixation element in a first, lengthwise orientation along a pathway extending from a minimally invasive percutaneous incision to a spinal anchor site. As the spinal fixation element approaches the spinal anchor site, the fixation element can be manipulated to extend in a second orientation, which is preferably substantially transverse to the first orientation, to position the fixation element in relation to one or more spinal anchors.

1 .- 20 . (canceled) 
     
     
         21 . A tool assembly for positioning a fixation rod in a bone anchor implanted in a patient, the bone anchor having a rod receiving channel, and the tool assembly extending above a portion of skin of the patient during use, and comprising:
 a) an elongate guide tool member including an upper end portion, a lower side opening, and a lower end portion configured to engage and releasably attach to the bone anchor, whereby the lower side opening is aligned with the rod receiving channel of the bone anchor; and   b) an outer member surrounding the elongate guide tool member.   
     
     
         22 . The tool assembly according to  claim 21 , wherein:
 a) the guide tool member has engagement structure to releasably secure the guide tool member to mating structure on the bone anchor when the guide tool member is in engagement with the bone anchor.   
     
     
         23 . A tool assembly for positioning a fixation rod in a bone anchor implanted in a patient, the bone anchor having a rod receiving channel, and the tool assembly extending above a portion of skin of the patient during use, and comprising:
 a) an elongate guide tool member including an upper end portion, a lower side opening, and a lower end portion configured to engage and releasably attach to the bone anchor, whereby the lower side opening is aligned with the rod receiving channel of the bone anchor;   b) a member engaging the elongate guide tool member; and   c) the member cooperating with the elongate guide tool member to engage and push the fixation rod extending through the lower side opening of the guide tool member down into the bone anchor rod receiving channel when the member is advanced toward the bone anchor.   
     
     
         24 . The tool assembly according to  claim 23 , wherein an end of the member is configured to engage the fixation rod and urge the rod and bone anchor together. 
     
     
         25 . The tool assembly according to  claim 23 , wherein:
 a) the guide tool member has engagement structure to releasably secure the guide tool member to mating structure on the bone anchor when the guide tool member is in engagement with the bone anchor.   
     
     
         26 . In an insertion tool having an elongate body with a tool attachment structure at a lower end thereof adapted to be secured to an implant including a receiver with a channel formed by a pair of upwardly extending arms with internal surfaces having threads and external surfaces configured for attachment with the tool attachment structure, the improvement comprising:
 a) a through bore defining an interior of the body of the tool, the interior having tool threads formed in the body of the tool at an upper portion thereof opposite the lower end of the body;   b) a laterally opening channel formed in the body and communicating with the interior of the body, the laterally opening channel extending upwardly from the lower end of the body to the upper portion thereof so as to provide side access to the interior of the body, a portion of the laterally opening channel being sized to receive a longitudinal connecting member; and   c) the tool threads being sized and shaped for rotating mating engagement with a tool.   
     
     
         27 . In an insertion tool having an elongate body with a tool attachment structure at a lower end thereof adapted to be secured to an implant including a receiver with a channel formed by a pair of upwardly extending arms with internal surfaces having threads and external surfaces configured for attachment with the tool attachment structure, the improvement comprising:
 a) a through bore defining an interior of the body of the tool, the interior having tool threads formed in the body of the tool at an upper portion thereof opposite the lower end of the body;   b) a laterally opening channel formed in the body and communicating with the interior of the body, the laterally opening channel extending upwardly from the lower end of the body to the upper portion thereof so as to provide side access to the interior of the body, a portion of the laterally opening channel being sized to receive a longitudinal connecting member; and   c) a reduction tool configured to reduce the longitudinal connecting member down into the channel of the receiver to be engaged by the tool.   
     
     
         28 . The insertion tool of  claim 27 , wherein the reduction tool comprises a manipulator device effective to allow controlled movement of the longitudinal connecting member. 
     
     
         29 . The insertion tool of  claim 27 , wherein the reduction tool cooperates with the insertion tool to move the longitudinal connecting member down into the channel of the receiver in a controlled manner.