An instrument for insertion, implanting, and removing a cylindrical intervertebral spacer member having a deep circumferential groove, including: a shaft having a proximal end and a distal end, said proximal end forming a handle and the distal end forming a spacer member engaging subassembly; said spacer member engaging subassembly including at least one selectively expanding and contracting enclosure into which a central core of the spacer member may be introduced when the engaging subassembly is in the expanded state, and which holds the spacer member so that it cannot move when the selectively expanding and contracting enclosure is rendered into the contracted state; and an actuating mechanism, extending from the proximal end to the distal end, by which the spacer member engaging subassembly may be selectively expanded and contracted.