Clinical outcomes of BRYAN cervical disc arthroplasty: a prospective, randomized, controlled, multicenter trial with 24-month follow-up.

Study Design/Setting: Prospective, randomized, 3-center, clinical trial. Objective: To prospectively compare the outcomes of cervical arthroplasty with the BRYAN Cervical Disc Prosthesis (Medtronic Sofamor Danek, Inc, Memphis, TN) to anterior cervical discectomy and fusion (ACDF). Summary of Background Data: Surgical treatment of cervical disc pathology commonly involves techniques that employ discectomy and fusion (ACDF). This "gold-standard" technique has demonstrated good clinical and radiographic outcomes. Common adverse effects of this procedure are associated with the adjacent level degeneration and bone-graft harvest. Several investigators have independently reported successful short-term outcomes with the BRYAN Cervical Disc Prosthesis. In addition, a significant body of knowledge has been collected regarding the wear patterns and adjacent level effects of this device in human and animal models. Methods: As part of an FDA IDE trial, 3 centers collected prospective outcomes data on 115 patients randomized in a 1:1 ratio to ACDF (Control group) or arthroplasty with the BRYAN Cervical Disc Prosthesis (Investigational group). Results: Demographic and surgical data were generally similar in the 2 populations. Outcomes data collected at routine postoperative intervals for 24 months demonstrated that the Investigational group had statistically significant (P < 0.05) improvements as assessed by the Neck Disability Index, the Neck Pain Score, and SF-36 Physical component scores. The improvement in the Mental Component Subscore values for the BRYAN and control groups was equivalent at 24 months (P = 0.055). Arm pain relief was similar in both groups (P = 0.152). During the course of the 2-year follow-up, 4 patients in the Control group required surgical intervention and 3 patients in the Investigational group required ACDF for adjacent level disease. Conclusions: At 24 months, cervical arthroplasty with the BRYAN Cervical Disc Prosthesis compares favorably with ACDF as defined by standard outcomes scores.