Comparison of Bryan versus ProDisc-C total disk replacement as treatment for single-level cervical symptomatic degenerative disk disease.

PURPOSE: The purpose of this retrospective trial was to compare the role of the Bryan with ProDisc-C total disk replacement (TDR).

MATERIALS AND METHODS: Data were collected before surgery and 1, 3, 6, 12, and 24 months after surgery. Disability and pain were assessed using the Neck Disability Index (NDI) and the Visual Analog Scale of the neck and of the arm pain. SF-36 outcome measures were obtained including the physical component score as well as the mental component score. Functional spinal unit (FSU) was examined on lateral radiographs at 24-month follow-up. Occurrences of heterotopic ossification (HO) were detected from 24-month follow-up X-rays.

RESULTS: The mean NDI, mean VAS, and mean SF-36 scores were not statistically different between groups before surgery and at 24-month follow-up. At 24 months: Bryan 49 and ProDisc-C 53 (P > 0.05). The FSU angle increased slightly for the Bryan group (from 0.7 to 0.8°, P > 0.05), while for the ProDisc-C group, it increased significantly (from 0.5 to 2.3°, P < 0.05). There were 2 additional operations in this series: 1 in the Bryan group and 1 in the ProDisc-C group. There were no intraoperative complications, no vascular or neurologic complications, no spontaneous fusions, and no device failures or explantation. No significant difference was noted in terms of HO formation.

CONCLUSION: Both the Bryan and the ProDisc-C TDR resulted in satisfactory clinical outcome. Moreover, Bryan TDR can maintain the lordosis of FSU, whereas ProDisc-C TDR can restore the lordosis of FSU, whether or not this radiographic evidence leads to more favorable clinical outcome for ProDisc-C TDR requires further investigation.