Abstract: A surgical tool for use in spinal stabilization for fusing contiguous vertebra in an animal spine. The tool includes a distal end having external dimensions sized for the distal end to be inserted within the animal body and located against a tissue layer between contiguous vertebra. Cutting blades are carried on the distal end for cutting at least a portion of the layer and at least a portion of vertebra bodies to form a chamber within the contiguous vertebra. The cutting blades are selected for the chamber to be sized greater than the external dimensions of the distal end. A control element is provided for controlling a depth of cut of the cutting blade between at least first and second positions with the cutting blade retained within the external dimensions when in the first position and with the cutting blade extended to form the chamber when in the second position.

Abstract: A coil fusion implant is formed as a length of wire helically wound up or torqued about a center axis. It has terminal sections at opposed ends that can be releasably gripped and axially twisted about the reference axis to reduce the outer diameter of the coil. The coil can be screwed into place between opposing bony surfaces of a joint while it is constrained in a reduced diameter state. Following its insertion between the prepared bony surfaces, the coil is permitted to gradually recoil as its diameter increases. The coil, in its expanded state then exerts compressive forces radially outward against the bone surfaces in opposition to forces exerted by the ligaments and other tissues connecting the contacted bones of the joint.

Abstract: A surgical tool is disclosed for use in spinal stabilization for fusing contiguous vertebra in an animal spine. The tool includes a distal end having external dimensions sized for the distal end to be inserted within the animal body and located against a tissue layer between contiguous vertebra. Cutting blades are carried on the distal end for cutting at least a portion of the layer and at least a portion of vertebra bodies to form a chamber within the contiguous vertebra. The cutting blades are selected for the chamber to be sized greater than the external dimensions of the distal end. A control element is provided for controlling a depth of cut of the cutting blade between at least first and second positions with the cutting blade retained within the external dimensions when in the first position and with the cutting blade extended to form the chamber when in the second position.

Abstract: An expandable spinal implant is disclosed. The implant includes a plurality of ribs which are deformable between first and second states. In the first state, the ribs present a generally cylindrical implant. In the expanded second state, the ribs are arced outwardly to define a generally spherical implant. A tie mechanism is provided for urging the ribs between the first and second states and for holding the ribs in the expanded state. A novel surgical method is disclosed for stabilizing the spine by inserting the implant in the first state between opposing vertebrae and expanding the implant to the second state.

Abstract: A spinal stabilization method is disclosed for fusing contiguous vertebra in an animal spine. The method includes the steps of forming an access opening into at least a layer of tissue disposed between contiguous vertebra to be fused. Additional portions of the tissue layer as well as material of the vertebra body portions are removed to form an enlarged chamber disposed between the contiguous vertebra. The chamber is at least partially filled with a graft medium.