A spinal surgery system having a base, a cross member suspended from the base, and a pair of cannula guides suspended from the cross member, wherein the cannula guides are adapted to hold cannulae received therein such that the canulae remain co-planar with one another as the cannula guides are moved to various positions in the patient's intervertebral plane. By first suspending a pair of radiopaque markers in the cannual guides, and then viewing the image of the radiopaque markers, the cannulae guides can be aligned so that when the radiopaque markers have been removed and replaced with cannulae, the cannulae can be positioned along various paths which are disposed in the patient's intervertebral plane such that surgical tools can be advanced in preferred paths toward the patient's intervertebral space.