Patent ID: 8439832

Claim:
A system for forming an operating corridor to a lumbar spine, comprising: a distraction assembly to create a tissue distraction corridor in a lateral, trans-psoas path to a lumbar spine, wherein said distraction assembly includes an elongate inner element and a plurality of dilators, the plurality of dilators being configured to sequentially advance along the lateral, trans-psoas path to the lumbar spine, the elongate inner element being positionable in a lumen of an initial dilator of the plurality of dilators, wherein at least one instrument from the group consisting of said elongate inner element and said dilators includes a stimulation electrode that outputs electrical stimulation for nerve monitoring when the at least one instrument is positioned in the psoas muscle; a three-bladed retractor tool slidable over an exterior of an outermost sequential dilator of the dilator system toward the targeted spinal disc along the lateral, trans-psoas path, the three-bladed retractor assembly including: a blade-holder assembly, and a posterior-most retractor blade, a cephalad-most retractor blade, and a caudal-most retractor blade that extend from the blade-holder assembly, wherein the posterior-most, cephalad-most, and caudal-most retractor blades are slidably advanced over the exterior of the outermost sequential dilator while in a first position, wherein the blade-holder assembly is adjustable to move the posterior-most, cephalad-most, and caudal-most retractor blades to a second position in which the cephalad-most and caudal-most retractor blades are spaced apart from the posterior-most retractor blade to define an operative corridor, wherein three-bladed retractor tool is configured to define the operative corridor along the lateral, trans-psoas path to the lumbar spine in which a space extending to the targeted spinal disc between the posterior-most, cephalad-most, and caudal-most refractor blades is dimensioned so as to pass an implant through the operative corridor along the lateral, trans-psoas path to the lumbar spine.