Clinical Outcomes of a Zero Profile Implant for Single-Level Anterior Cervical Discectomy and Fusion

ABSTRACT

STUDY DESIGN: A retrospective study. OBJECTIVES: To evaluate and compare the clinical results of a zero profile implant with a conventional stand-alone cage. SUMMARY OF LITERATURE REVIEW A new zero-profile interbody fusion implant named Zero-P was developed in order to avoid plate-related complications. MATERIALS AND METHODS: Twenty-three patients with cervical degenerative disc disease were enrolled. Twelve of these were implanted with a stand-alone cage, and 11 patients received a Zero-P. The mean follow-up time was 16.7 months, ranging from 12 to 34 months. Intraoperative parameters, clinical outcomes (Korean Neck Pain Disability Index [K-NDI], visual analog scale [VAS] score for neck/arm pain), dysphagia scores, and device-related complications were recorded. RESULTS: At the 6-week, 3-month, 6-month, and 12-month follow up, the K-NDI and VAS scores significantly improved in both groups. Dysphagia scores in both groups have no significant differences (p>0.05). However, the cage subsidence rate was significantly higher in the stand-alone cage group (p<0.05). CONCLUSIONS: Clinical outcomes of ACDF with the Zero-P were satisfactory. The incidence of cage subsidence was lower than with the conventional stand-alone cage.