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...http://www.google.es/patents/US20040225361?utm_source=gb-gplus-sharePatente US20040225361 - Intervertebral disk nuclear augmentation system
