An intervertebral scaffolding system is provided having a laterovertically-expanding frame operable for a reversible collapse from an expanded state into a collapsed state, the laterovertically-expanding frame having a stabilizer, one or more tensioners, or a combination of the stabilizer with one or more tensioners. The stabilizer slidably engages with the distal region of the laterovertically-expanding frame and both the stabilizer and the one or more tensioners are configured for retaining the laterovertically-expanding frame from a lateral movement that exceeds the expanded state, and the stabilizer can include a locking element that engages with the expansion member to lock the expansion member to the stabilizer when the expansion member is fully inserted into the frame. The expanded state, for example, can be configured to have an open graft distribution window that at least substantially closes upon the reversible collapse.