Embodiments of the invention are directed to a method of directing medical instruments towards an intervertebral disc space, removing intervertebral disc material from such disc space, and filling such disc space with a material to fuse vertebrae. Embodiments of the invention are further directed to a path that passes structural portions of an ilium. In some aspects, embodiments of the invention are directed to using electro stimulation to avoid certain nerve roots to access an L5-S1 disc space for the purposes of bone fusion.