INTERVERTEBRAL DISK NUCLEAR AUGMENTATION SYSTEM

摘要

Various implants are provided to at least partially replace a nucleus of a spinal disk. The implants are spring-like in nature. In one embodiment, a helical spring is provided with various different unique outlines to act as the implant. The helical spring is oriented with a center line substantially perpendicular to the spine and to a direction of compression loads experienced within the disk space. The helical spring or other implant is preferably delivered through a delivery cannula which has a size which is smaller than a cross-sectional size of the implant. The implant is preferably formed of nickel titanium or otherwise configured so that it can be compressed significantly within the delivery cannula and then become enlarged after being advanced out of the delivery cannula and into the intervertebral space. In other embodiments the implant is generally cylindrical and expandable in height after delivery.