Outcomes Following Anterior Cervical Discectomy and Fusion with Plating and Self-drilling, Self-tapping Screws: A Single Surgeon’s Experience in 50 Consecutive Patients
Medical Student University of Arizona College of Medicine - Phoenix Glendale, AZ, US
Disclosure(s):
Nikhil Dholaria, BS, BA: No financial relationships to disclose
Introduction: The use of plating in anterior cervical discectomy and fusion (ACDF) has evolved to improve fusion stability and enhance patient outcomes. While early self-tapping screws benefit in securing the construct, advancements of screw design, such as self-drilling tips, aided in ensuring precise screw placement and fusion while minimizing damage to adjacent tissues. This study aims to compare the outcomes and complications with self-drilling, self-tapping screws and evaluate their efficacy in maintaining instrumentation position.
Methods: Patients who underwent ACDF with plating and self-drilling, self-tapping screws from February 2021 to May 2023 were consecutively included in our retrospective case series. Demographics, intraoperative characteristics and postoperative data were collected. The C2-C7 Cobb angle and C2-C7 sagittal vertical axis (SVA) were also collected from preoperative, immediate postoperative, and final follow-up lateral radiographs. Odds ratios (ORs) were also utilized to determine factors associated with abnormal C2-C7 Cobb angles and C2-C7 SVAs postoperatively.
Results: A total of 50 patients (26M, 24F, mean age: 56.7 ± 10.4) operated on at an average of 1.8 levels were included. Average length of stay was 1.4 ± 2.0 days with an average clinical follow-up of 242.4 ± 229.3 days and an average radiographic follow-up was 251.1 ± 226.5 days. From preoperative to final postoperative radiographic follow-up, the C2-C7 Cobb angle increased by 21.03%, with the C2-C7 SVA increasing by 3.25%. OR assessment found an association with the American Society of Anesthesiologists (ASA) physical status classification score of ≥ 3 and abnormal postoperative C2-C7 SVA (95% CI: 0.033 to 0.937, p=0.042). Longer operative times (≥91.5 minutes) was less likely to be associated with abnormal postoperative C2-C7 Cobb angles when compared to shorter operative times (0.175, 95% CI: 0.032 to 0.952, p=0.044). No fixation system complications or evidence of radiographic or clinical pseudoarthrosis were noted on any of the postoperative x-rays until final follow-up. Though four patients required a secondary surgery, there were no revision surgeries.
Conclusion : Patients undergoing ACDF with unicortical self-drilling, self-tapping screws to fixate the plate had excellent postoperative radiographic outcomes. No evidence of instrumentation complications, including pseudoarthrosis, were evidenced. This cohort demonstrates the safety of ACDF with this screw design.