Selectively expanding spine cage, hydraulically controllable in three dimensions for enhanced spinal fusion

A selectively expandable spinal implant for posterior insertion between opposed superior and inferior vertebral end plates of a patient, comprising:

• a cylinder block defining two or more slave cylinders, and a central cavity between said cylinders adapted to receive bone graft material;
• two or more corresponding pistons positioned within said cylinders to provide a corrective bone engaging surface for expanding against a first vertebral end plate;
• and
• said cylinder block comprising a base for resting on a second vertebral end plate, the base defining an opening therethrough communicating with said central cavity and with an intervertebral space after insertion of the implant.

An implant positionable between first and second vertebral bodies, comprising:

• a base member;
• at least two first members each including first sidewalls that extend around and form a first interior space, said first members disposed on the base member;
• at least two second members each including second sidewalls that extend around and form a second interior space, with each said second member slidable in a corresponding first member;
• a top member disposed on said at least two second members opposite the base member;
• and
• at least one of the first and second members positionable between collapsed and expanded orientations, with the collapsed orientation comprising the second member nested within the first interior space of the first member, with the first and second sidewalls overlapping and with the expanded orientation comprising the second member extending from the first member;
• wherein at the first members, second members, base member and top member define therebetween a central cavity configured for placement of bone graft material therein.

An apparatus for providing spinal correction, comprising:

• a selectively expandable spinal implant for insertion between opposed vertebrae of a patient, said implant comprising:
• a base member configured and dimensioned to engage one said vertebra;
• at least two cylinders carried by said base member;
• at least first and second pistons respectively disposed in said cylinders, said pistons being configured to be rigidly fixed at an extended position;
• a bone engaging member cooperating with pistons opposite the base member and configured and dimensioned to engage the opposite vertebra:
• and
• wherein the base member, the bone engaging member, and each cylinder and piston received therein define therebetween a central cavity for configured to receive bone graft material, and the base member and the bone engaging member define openings therethrough communicating said central cavity.

An apparatus for providing spinal correction, comprising:

• a selectively expandable spinal implant for insertion between opposed vertebrae of a patient, said implant comprising:
• a base member configured and dimensioned to engage one said vertebra;
• at least two cylinders carried by said base member;
• at least first and second pistons respectively disposed in said cylinders, said pistons being configured to be actuated by fluid applied to the cylinders and rigidly fixed at an extended position;
• a bone engaging member cooperating with pistons opposite the base member and configured and dimensioned to engage the opposite vertebra
• an insertion tool for inserting the implant and delivering fluid to the cylinders, said insertion tool being releasably engageable with said implant and comprising a handle with an insertion end configured to engage and insert the implant into an insertion opening.