Methods and Apparatuses for Vertebral Body Distraction and Fusion Employing a Coaxial Screw Gear Sleeve Mechanism

A method comprising:

• causing a distractible intervertebral body fusion device to be manufactured and made available, the device including a first bearing surface, a second bearing surface, and at least one coaxial screw gear sleeve mechanism disposed between the first bearing surface and the second bearing surface, the coaxial screw gear sleeve mechanism including a threaded post, a corresponding sleeve having an interior thread mating with the threaded post and a helically geared exterior surface adapted to mate with a drive mechanism;
• providing instructions on a tangible medium for performing an intervertebral body fusion and distraction procedure with the distractible intervertebral body fusion device, the instructions comprising:
• inserting the distractible intervertebral body fusion device in a compressed configuration into an intervertebral disc space of a patient defined between adjacent vertebrae such that the first bearing surface interfaces with an end plate of a superior vertebra of the intervertebral disc space and the second bearing surface interfaces with an end plate of an inferior vertebra of the intervertebral disc space;
• distracting the device into an expanded configuration by operating the drive mechanism to rotate the sleeve, thereby telescopically expanding the first bearing surface with respect to the second bearing surface by causing the sleeve to translate relative to one of the first bearing surface and the second bearing surface simultaneously with the threaded post translating relative to the sleeve to distract the end plate of the superior vertebra relative to the end plate of the inferior vertebra of the intervertebral disc space.

A method of intervertebral body distraction and fusion comprising:

• inserting a distractible intervertebral body fusion device into an intervertebral disc space defined between adjacent vertebrae, the distractable device including a first bearing surface configured to interface with an end plate of a superior vertebra of the intervertebral disc space, a second bearing surface configured to interface with an end plate of an inferior vertebra of the intervertebral disc space, and at least one coaxial screw gear sleeve mechanism disposed between the first bearing surface and the second bearing surface, the coaxial screw gear sleeve mechanism including a threaded post, a corresponding sleeve having an interior thread mating with the threaded post and an exterior gear adapted to mate with a drive mechanism;
• and
• distracting the distractable device from a collapsed configuration to an expanded configuration by operating the drive mechanism to rotate the sleeve relative to the post, thereby telescopically expanding the first bearing surface with respect to the second bearing surface by causing the sleeve to translate relative to one of the first bearing surface and the second bearing surface simultaneously with the threaded post translating relative to the sleeve to distract the end plate of the superior vertebra relative to the end plate of the inferior vertebra of the intervertebral disc space.

A method comprising:

• causing a size-adjustable implant to be manufactured and made available, the implant including a first member, a second member and a size-adjustable support engaging the first and second members to provide an adjustable separation distance between the first and second members, the support comprising commonly-actuated, coaxial first and second axially rotatable joints to provide the adjustable separation distance, wherein the support comprises a first sleeve member and a second sleeve member, the first sleeve member rotationally mounted in a first threaded lumen with the first member and the second member rotationally mounted in a second, substantially parallel threaded lumen with the first member;
• providing instructions on a tangible medium for performing an intervertebral body fusion and distraction procedure with the implant, the instruction comprising:
• inserting the implant between first and second vertebral bodies in a compressed configuration such that the first member contacts the first vertebral body and the second member contacts the second vertebral body;
• and
• expanding the implant into an expanded configuration by actuating the first and second axially rotatable joints.