EXPANDABLE INTERVERTEBRAL IMPLANT

摘要

An implant for therapeutically separating bones of a joint has two endplates each having an opening through the endplate, and at least one ramped surface on a side opposite a bone engaging side. A frame is slideably connected to the endplates to enable the endplates to move relative to each other at an angle with respect to the longitudinal axis of the implant, in sliding connection with the frame. An actuator screw is rotatably connected to the frame. A carriage forms an open area aligned with the openings in the endplates. The openings in the endplates pass through the carriage to form an unimpeded passage from bone to bone of the joint. The carriage has ramps which mate with the ramped surfaces of the endplates, wherein when the carriage is moved by rotation of the actuator screw, the endplates move closer or farther apart.

主权项

1. An implant, having a longitudinal axis defined between a proximal end of the implant and a distal end of the implant, for placement between adjacent vertebrae comprising:
a first end plate configured to engage a superior vertebra; a second endplate configured to engage an inferior vertebra adjacent to the superior vertebra; a first bone screw socket, corresponding to the superior vertebra and disposed on the proximal end of the implant, configured to receive a first bone screw; a second bone screw socket, corresponding to the inferior vertebra and disposed on the proximal end of the implant, configured to receive a second bone screw; an actuator comprising a frame, a carriage, and an actuator screw, said actuator disposed in between the first endplate and the second endplate; wherein the carriage is configured to engage one or more ramps disposed on each of the first endplate and second endplate, wherein the actuator screw is configured to rotate within the frame and the carriage is configured to move within frame upon rotation of the actuator screw, and wherein the first end plate and second end plate are configured to separate in a direction transverse to the longitudinal axis of the implant when the actuator screw is rotated in a first direction and converge in direction transverse to the longitudinal axis when the actuator screw is rotated in a second direction, wherein movement of the first endplate and the second endplate is directed by the carriage engaging the one or more ramps disposed on each of the first endplate and the second endplate.