AUTHOR=Jin Zhe-yu , Teng Yun , Wang Hua-zheng , Yang Hui-lin , Lu Ying-jie , Gan Min-feng 

TITLE=Comparative Analysis of Cage Subsidence in Anterior Cervical Decompression and Fusion: Zero Profile Anchored Spacer (ROI-C) vs. Conventional Cage and Plate Construct

JOURNAL=Frontiers in Surgery

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/surgery/articles/10.3389/fsurg.2021.736680

DOI=10.3389/fsurg.2021.736680

ISSN=2296-875X

ABSTRACT=<p><bold>Background:</bold> Anterior cervical discectomy and fusion (ACDF) has been widely performed to treat cervical generative diseases. Cage subsidence is a complication after ACDF. Although it is known that segmental kyphosis, acceleration of adjacent segmental disease, and restenosis may occur due to cages subsidence; however detailed research comparing zero-profile cages (ROI-C) and conventional plate and cage construct (CPC) on cage subsidence has been lacking.</p><p><bold>Objective:</bold> The objectives of this study was to compare the rate of postoperative cage subsidence between zero profile anchored spacer (ROI-C) and conventional cage and plate construct (CPC) and investigate the risk factors associated with cage subsidence following ACDF.</p><p><bold>Methods:</bold> Seventy-four patients with ACDF who received either ROI-C or CPC treatment from October 2013 to August 2018 were included in this retrospective cohort study. Clinical and radiological outcomes and the incidence of cage subsidence at final follow up-were compared between groups. All patients were further categorized into the cage subsidence (CS) and non-cage subsidence (NCS) groups for subgroup analysis.</p><p><bold>Results:</bold> The overall subsidence rate was higher in the ROI-C group than in the CPC group (66.67 vs. 38.46%, <italic>P</italic> = 0.006). The incidence of cage subsidence was significantly different between groups for multiple-segment surgeries (75 vs. 34.6%, <italic>P</italic> = 0.003), but not for single-segment surgeries (54.55 vs. 42.30%, <italic>P</italic> = 0.563). Male sex, operation in multiple segments, using an ROI-C, and over-distraction increased the risk of subsidence. Clinical outcomes and fusion rates were not affected by cage subsidence.</p><p><bold>Conclusion:</bold> ROI-C use resulted in a higher subsidence rate than CPC use in multi-segment ACDF procedures. The male sex, the use of ROI-C, operation in multiple segments, and over-distraction were the most significant factors associated with an increase in the risk of cage subsidence.</p>