A spinal surgery tool system including an elongated conduit and an implant is disclosed. The implant assumes a straight configuration within the elongated conduit and is deployable from the elongated conduit into a closed or nearly-closed loop configuration for deployment interposed between two tissue surfaces to define an enclosed volume. The conduit and the implant are configured such that, when the implant is deployed in the loop configuration, an opening formed in a proximal portion of the implant forms a contiguous channel with a passageway along the conduit so as to provide a continuous access channel along the elongated conduit into the enclosed volume.