[Comparison of effectiveness between zero-profile anchored cage and plate-cage construct in treatment of consecutive three-level cervical spondylosis].

Abstract

Objective: To evaluate the safety and effectiveness of anterior cervical discectomy and fusion (ACDF) by using zero-profile anchored cage (ZAC) in treatment of consecutive three-level cervical spondylosis, by comparing with plate-cage construct (PCC).

Methods: A clinical data of 65 patients with cervical spondylosis admitted between January 2020 and December 2022 and met the selection criteria was retrospectively analyzed. During consecutive three-level ACDF, 35 patients were fixed with ZAC (ZAC group) and 30 patients with PCC (PCC group). There was no significant difference in baseline data between the two groups ( P>0.05), including gender, age, body mass index, surgical segment, preoperative Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), visual analogue scale (VAS) score, prevertebral soft tissue thickness (PSTT), cervical lordosis, and surgical segmental angle. The operation time, intraoperative blood loss, hospital stay, clinical indicators (JOA score, NDI, VAS score), and radiological indicators (cervical lordosis, surgical segmental angle, implant subsidence, surgical segment fusion, and adjacent segment degeneration), and the postoperative complications [swelling of the neck (PSTT), dysphagia] were recorded and compared between the two groups.

Results: Patients in both groups were followed up 24-39 months. There was no significant difference in follow-up duration between the two groups ( P>0.05). The operation time and intraoperative blood loss were lower in ZAC group than in PCC group, and the length of hospital stay was longer, but there was no significant difference ( P>0.05). At each time point after operation, both groups showed significant improvements in JOA score, VAS score, and NDI compared with preoperative scores ( P<0.05), but there was no significant difference between the two groups at each time point after operation ( P>0.05). Both groups showed an increase in PSTT at 3 days and 3, 6 months after operation compared to preoperative levels ( P<0.05), but returned to preoperative levels at last follow-up ( P>0.05). The PSTT at 3 days and 3 months after operation were significantly lower in ZAC group than in PCC group ( P<0.05), and there was no significant difference between the two groups at 6 months and at last follow-up ( P>0.05). The incidences of dysphagia at 3 days and 3 months were significantly lower in ZAC group than in PCC group ( P<0.05), while no significant difference was observed at 6 months and last follow-up between the two groups ( P>0.05). There was no postoperative complication in both groups including hoarseness, esophageal injury, cough, or hematoma. Both groups showed improvement in cervical lordosis and surgical segmental angle compared to preoperative levels, with a trend of loss during follow-up. The cervical lordosis loss and surgical segmental angle loss were significantly more in the ZAC group than in PCC group ( P<0.05). The incidence of implante subsidence was significantly higher in ZAC group than in PCC group ( P<0.05). There was no significant difference between the ZAC group and PCC group in the incidences of surgical segment fusion and adjacent segment degeneration ( P>0.05).

Conclusion: In consecutive three-level ACDF, both ZAC and PCC can achieve satisfactory effectiveness. The former can reduce the incidence of postoperative dysphagia, while the latter can better maintain cervical curvature and reduce the incidence of implant subsidence.