Patent ID: 8579979
Filing Date: 2013-11-12
Classification: A61F

Abstract:
1. An intervertebral spacer comprising: an inferior member including a body having a bottom surface being configured to contact a vertebral body, the body defines a main cavity therein; a superior member including a plate having a top surface being configured to engage an adjacent vertebral body, the top surface including a guide member extending therefrom; a guide hole defined in the inferior member, the guide hole being configured to receive the guide member; and a jack mechanism disposed in the main cavity, wherein the jack mechanism is configured to cause the inferior and superior members to move in a first direction such that the inferior and superior members move apart and in a second direction such that the inferior and superior members move towards each other; wherein the jack mechanism includes a screw shaft extending from a bottom surface of the plate and a ring gear rotatably mounted in the main cavity, wherein the ring gear is internally threaded to mesh with the externally threaded screw shaft such that when the ring gear is rotated in a first direction, the superior member is raised relative to the inferior member and when the ring gear is rotated in a second direction, the superior member is moved toward the inferior member; wherein a drive gear meshes with the ring gear, the drive gear being configured to rotate the ring gear; wherein the drive gear includes an axial bore configured to receive a mounting shaft being rotatably journaled in the main cavity of the inferior member, the mounting shaft includes a head having a socket for receiving a tool.