107 patients with single-level cervical spondylosis were randomized to undergo either cervical disc arthroplasty (CDA) with the Mobi-C Cervical Disc Prosthesis or ACDF. The purpose of this study was to compare patient-reported outcome measures, the radiographic range of motion of the index segment, and subsequent surgery rates between groups. At 5 year follow-up, no significant differences were observed in patient-reported outcome measures. Subsequent surgery rates were significantly lower in the CDA group compared to the ACDF group, and range of motion of the index level was significantly higher in the CDA