Artificial disc device

摘要

An artificial disc device for replacing a damaged nucleus is disclosed. In one form, the device may be inserted in components such that the device may be assembled within and retained by the natural annulus therein. In another form, the device may be inserted into the natural annulus in a collapsed or compressed state or arrangement and then be expanded within and retained by the annulus therein. In a further form, the device may be provided with a releasable connection so that the device may be connected in an insertion configuration and may be released in an operable configuration. Insertion tools and methods are also disclosed.

主权项

1. A method of replacing a nucleus of a spinal disc, the steps including:
providing an implant device comprising distinct upper and lower disc members having mating inner arcuate bearing surfaces configured to slidingly engage one another to allow the disc members to shift polyaxially with respect to one another and each having a major dimension extending along a longitudinal axis and a minor dimension transverse to the longitudinal axis; forming an opening in an annulus of the spinal disc having a predetermined size and defining an insertion axis about which the opening extends; attaching the upper disc member to a distal end of an inserter instrument at a tool engaging portion of the upper disc member to form a pivotal connection therebetween; attaching the lower disc member to the distal end of the inserter instrument at a tool engaging portion of the lower disc member to form a pivotal connection therebetween such that each one of the upper and lower disc members is held independently of the other one of the upper and lower disc members by the inserter instrument in a superimposed orientation such that the distinct upper and lower disc members are kept from separating, and each one of the upper and lower disc members is configured to be pivoted about its respective pivotal connection at the distal end of the inserter instrument; orienting the device with the longitudinal axis aligned with the insertion axis of the opening to keep the predetermined opening size to a minimum; inserting the device through the opening into the nuclear space along the insertion axis; and pivoting the device relative to the distal end of the inserter instrument while the device is attached thereto within the nuclear space so that the longitudinal axis of the implant device is transverse to the insertion axis; releasing the distinct upper and lower disc members from the distal end of the inserter instrument in the nuclear space.