Trial Evaluating the Safety and Effectiveness of NUBAC™ Disc Arthroplasty

STUDY DESIGN: Multicenter, prospective, randomized (1:1), controlled study comparing the artificial nucleus to ProDisc. After implanting artificial nucleus in two patients during the training session, enrollment of randomized patients shall begin. The study is expected to be completed in four years. NUMBER OF INVESTIGATIONAL SITES and INVESTIGATORS: 10 - 20 investigational sites, 1 to 2 investigators per site, approximately 20-40 patients per site