Expandable spinal implant apparatus and method of use

摘要

A spinal implant apparatus that is an expandable spacer including features to minimize or eliminate spacer cant or offset during and after completing the expansion process. The spacer includes a top component, a base component in engagement with the top component, and an expansion mechanism arranged to change the top component's position with respect to the base component. The mechanism for causing expansion may be a screw, a cam, a wedge or other form of distracting device. In one embodiment, the expandable spacer includes a base component with a set of towers and a top component with a set of corresponding silos, where the towers and silos are configured to minimize or eliminate tilt of the top component as it extends upwardly from the base component. In another embodiment, the spacer may include a stepped arrangement around the perimeter of the top component and the base component for engagement during height expansion with minimal canting or slippage. In another embodiment, the spacer may include texturing modification at the opposite ends of the longitudinal axis of the spacer to prevent tilting, slipping, or canting. Additionally, a portion of one or more exterior surfaces of the spacer may be textured, sawtoothed, dovetailed or the like to increase frictional intervertebral contact. The spacer may contain one or more passageways of selectable shape/dimension for bone growth through the spacer.

主权项

1. A method of implanting a spinal spacer into an intervertebral space of a patient, comprising:
engaging a tip of an insertion tool to a threaded on-axis interface of the spacer substantially parallel to a longitudinal axis of the spacer; inserting a front end of the spacer into the intervertebral space along an insertion direction substantially parallel to the longitudinal axis of the spacer; continuing to insert the spacer so that the front end of the spacer turns until the longitudinal axis of the spacer is non-parallel to the insertion direction; further inserting the spacer into the intervertebral space while the insertion tool is non-parallel to the longitudinal axis of the spacer; and actuating an expansion mechanism to expand the spacer by increasing a distance between a top surface of the spacer and a bottom surface of the spacer, the expansion mechanism being angled with respect to the longitudinal axis of the spacer; wherein the insertion tool includes a shaft configured for positioning outside the intervertebral space while the spacer is within the intervertebral space, the shaft of the insertion tool being non-pivotable with respect to the tip of the insertion tool, the tip configured to be threadedly coupled to the spacer during the step of actuating the expansion mechanism.