Method of lumbar intervertebral disk stabilization

A method of intervertebral disk stabilization comprising the steps of:

• spreading adjacent vertebrae by inserting a spreader comprised of a handle and an integral implant portion between the adjacent vertebrae,
• removing a portion of the intervertebral disk from between the adjacent vertebrae;
• inserting the implant portions of additional spreaders between the adjacent vertebrae, each of the additional spreaders having implant portions of increasingly larger diameters, to spread the adjacent vertebrae progressively further apart;
• inserting an elongate, generally cylindrically-shaped implant having middle and end portions, the middle portion being an expanded larger diameter than the end portions, into the space between the adjacent vertebrae from which a portion off the disk has been removed, the implant portions of the respective spreaders being shaped in a shape similar to the elongate implant;
• and
• rotating the elongate implant to cause threads formed on the outside surface thereof to bear against the adjacent vertebrae to move the implant in an anterior-posterior direction until positioned at a point between the adjacent vertebrae at which both the larger diameter middle portion and the smaller diameter end portion of the elongate implant engage the bodies of the adjacent vertebrae to stabilize the adjacent vertebrae relative to each other.