OBJECTIVETo compare clinical efficacy of Zero-profile implant for anterior cervical discectomy and fusion and conventional titanium plate with cage internal fixation for the treatment of single segmental cervical intervertebral disc herniation.

METHODSFrom August 2011 to March 2014, clinical data of 139 patients with single cervical disc herniation treated with anterior cervical discectomy and interbody fusion with internal fixation were retrospectively analyzed. The patients were divided into two groups according to its operation method. There were 63 patients in group A which performed anterior discectomy and interbody fusion with Zero-profile;76 patients in group B which performed anterior cervical discectomy and cage plate internal fixation. JOA score and Odom functional rating between two groups were compared before and after operation. Videofluorographic swallowing study (VFSS) were used to evaluate thickness of prevertebral soft tissue. Bazaz dysphagia score were used to assess incidence of dysphagia. Postoperative AP X-ray and CT of cervical vertebra at 12 months were applied for evaluating bone graft fusion. Postoperative MRI was applied for evaluating the incidence of adjacent segment degeneration. Blood loss,operative time, preoperative and postoperative JOA score, Odom functional rating and VFSS score, Bazaz score, fusion rate between vertebral bodies and incidence of adjacent segment degeneration were compared between two groups.

RESULTSThere were no statistical meaning between two groups in JOA score, Odom functional rating before and after operation (P > 0.05); and no significant meaning in VFSS score between two groups before operation (P > 0.05); There were no significant difference in operative time and blood loss. There was statistical meaning in VFSS, Bazaz dysphagia score at 2 days, and 6 months after operation (P < 0.05). All patients obtained bone union at 1 year after operation, and no obvious meaning in fusion rate (P > 0.05). Eight patients (12.7%) in group A occurred adjacent segment degeneration and 19 patients (25%) in group B occurred adjacent segment degeneration, and there was significant meaning between two groups (P < 0.05).

CONCLUSIONBoth of Zero-profile implant for anterior cervical discectomy and fusion and conventional cage internal fixation for the treatment of single segmental cervical intervertebral disc herniation could obtain satisfied clinical results. While Zero-profile implant for anterior cervical discectomy and fusion has advantages of lower incidence of adjacent segment degeneration, and its mid and long term following-up results still further observation.