Published date:Mar 13 2025

Journal Title: Journal of Spine Practice

Issue title: Journal of Spine Practice (JSP): Volume 4, Issue 2

Pages:1 - 10

DOI: 10.18502/jsp.v4i2.17675

Nikhil Dholarianikhildholaria10@arizona.eduUniversity of Arizona College of Medicine – Phoenix, Phoenix, AZ

Juan P. GiraldoDepartment of Neurosurgery, Barrow Neurological Institute, Phoenix, AZ

Sohail DaulatUniversity of Pittsburgh School of Medicine, Pittsburgh, PA

James KelbertUniversity of Arizona College of Medicine – Phoenix, Phoenix, AZ

Vick S. SahniUniversity of Arizona College of Medicine – Phoenix, Phoenix, AZ

Giovanni BarbagliDepartment of Neurosurgery, Banner University Medical Center – Phoenix, Phoenix, AZ

Christina CannataDepartment of Neurosurgery, Banner University Medical Center – Phoenix, Phoenix, AZ

Diego T. Soto RubioDepartment of Neurosurgery, Tampa General Hospital, Tampa, FL

Annemarie PicoUniversity of Arizona College of Medicine – Phoenix, Phoenix, AZ

Amna HusseinDepartment of Neurosurgery, Banner University Medical Center – Phoenix, Phoenix, AZ

Abdullah Al-ArfajDepartment of Neurosurgery, Banner University Medical Center – Phoenix, Phoenix, AZ

Michael PrimDepartment of Neurosurgery, Banner University Medical Center – Phoenix, Phoenix, AZ

Ali A. BaajDepartment of Neurosurgery, Banner University Medical Center – Phoenix, Phoenix, AZ

Purpose

Even though plate and screw designs in anterior cervical discectomy and fusion (ACDF) have evolved to improve fusion stability and enhance patient outcomes, some argue that pre-tapping remained the best option. The purpose of this study is to evaluate the outcomes and complications of self-drilling, self-tapping screws and evaluate their efficacy in maintaining instrumentation position in plated ACDFs.

Methods

In this retrospective case series, patients who underwent ACDF with plating and selfdrilling, self-tapping screws from February 2021 to May 2023 were consecutively included. Demographic, radiographic, intraoperative, and postoperative data were collected. Odds ratios (ORs) were also utilized to determine factors associated with abnormal C2-C7 Cobb angles and C2-C7 sagittal vertical axes (SVAs) postoperatively.

Results

A total of 50 patients (26M, 24F, mean age: 56.7 ± 10.4) were included. At the final postoperative radiographic follow-up (251.1 ± 226.5 days), 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 (5.667, 95% CI: 1.067 to 30.086, p=0.042). Longer operative times (≥91.5 minutes) were 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.

Conclusion

Patients undergoing ACDF with self-drilling, self-tapping screws had excellent postoperative outcomes and no evidence of instrumentation complications, including pseudoarthrosis. This case series demonstrates the safety of ACDF with this screw design. However, future studies should include a larger cohort of patients to provide more accurate guidelines and recommendations.

Keywords: radiographic outcomes, implant complications, self-drilling, self-tapping screws, self-drilling screws, anterior cervical discectomy and fusion

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