A system for percutaneous spinal fusion may include two spaced apart blades connected together by a coupling such that the blades define a percutaneous pathway from a skin incision to an implanted pedicle fastener. The coupling may be c-shaped and may have at least one flexible tab for engaging one or more holes along the length of the blades. If one of the blades becomes disconnected from the pedicle fastener, a supplemental access device may be provided comprising a tubular body having a channel therein for receiving the other of the blades. If both of the blades become disconnected, a supplemental access device may be provided comprising a gripping member received within a locking member. The gripping member may have two legs engageable with the pedicle fastener, and the locking member may move along the gripping member to prevent the legs from disengaging the pedicle fastener.
