Midterm outcomes of total cervical total disc replacement with Bryan prosthesis

Abstract

Short-term results have indicated that the Bryan cervical total disc replacement (TDR) favorably compares to anterior cervical decompression and fusion, while it is associated with fewer complications and higher levels of satisfaction. The aim of the present work was to assess the safety and efficacy of the device in the treatment for cervical degenerative disc disease, at 6-year follow-up. Fifty-eighty patients have performed their 6-year follow-up visit and have been analyzed clinically and radiologically. Clinical evaluation was based on neck disability index (NDI), visual analog scale (VAS), SF-36, and range of motion (ROM) at index levels. Each measurement was taken preoperatively and at 3months, 6months, 1year, 3years, and 6years postoperatively. Complications and re-operations were also investigated. Occurrences of heterotopic ossifications (HO) and of adjacent level degeneration were detected by radiographs at 6-year follow-up. The mean NDI and VAS scores for arm and neck were significantly reduced for all postoperative periods compared with the average preoperative values. Motion was preserved at index levels (mean ROM=8.6°±0.2° at 6years), and 81.3% of the segments were mobile at 6years. HO was evident in 12/64 operated segments and not restricting the movement of the prosthesis in any case at 6-year follow-up. Six of sixty-four upper adjacent levels and 4/64 lower adjacent levels showed a slight degradation. There was 2 case of posterior migration of the prosthesis, which did not cause any clinical symptoms. No case showed evidence of subsidence, wear of the implant. At a 6-year follow-up, the cervical TDR using Bryan prosthesis displayed satisfactory clinical and radiographic outcomes without any significant complication. However, future efforts need to be directed toward the evaluation of a larger number of patients with longer follow-up.