Outcomes of Unstable Subaxial Cervical Spine Fractures Managed by Posteroanterior Stabilization and Fusion

Study Design Retrospective study. Purpose To evaluate clinical and radiological outcomes of unstable subaxial cervical spine injuries managed by both posterior tension band column stabilization and anterior decompression, stabilization, and fusion. Overview of Literature Unstable subaxial cervical spine injuries often involve disruption of the anterior column and posterior tension band osteoligamentous complex. Such injuries need immediate surgical intervention. Different methods of reduction and surgical approaches have been published in the literature, with lack of consensus on a uniform or standardized method. Controversy still exists regarding stabilization of unstable cervical fractures by anterior or posterior approach alone or combined approaches. Methods We retrospectively evaluated 24 patients with post-traumatic unstable subaxial cervical spine injuries with their preoperative clinical details, X-ray, computed tomography, and magnetic resonance imaging of the cervical spine for fracture classification based on the mechanism of injury with status of disc herniation and posterior tension band disruption. All patients were managed by immediate reduction, posterior and anterior stabilization, and fusion in a single session of anesthesia. Data of all patients were analyzed with respect to pre- and postoperative neurological status based on American Spinal Injury Association grading, Visual Analog Scale score, the observation of bony fusion, and implant failure at 1, 3, 6, and 12 months. Data were analyzed using paired t-test. Results All patients had solid fusion at the desired level with considerable neurological improvement at the 1-year follow-up. Conclusions In unstable cervical injuries, stabilization of disrupted posterior tension band increases the stability of anterior plating and fusion. This method of immediate reduction and circumferential stabilization is rapid, safe, and effective and has a low rate of complications

Effect of surgical experience and spine subspecialty on the reliability of the {AO} Spine Upper Cervical Injury Classification System

OBJECTIVE The objective of this paper was to determine the interobserver reliability and intraobserver reproducibility of the AO Spine Upper Cervical Injury Classification System based on surgeon experience (< 5 years, 5–10 years, 10–20 years, and > 20 years) and surgical subspecialty (orthopedic spine surgery, neurosurgery, and "other" surgery). METHODS A total of 11,601 assessments of upper cervical spine injuries were evaluated based on the AO Spine Upper Cervical Injury Classification System. Reliability and reproducibility scores were obtained twice, with a 3-week time interval. Descriptive statistics were utilized to examine the percentage of accurately classified injuries, and Pearson’s chi-square or Fisher’s exact test was used to screen for potentially relevant differences between study participants. Kappa coefficients (κ) determined the interobserver reliability and intraobserver reproducibility. RESULTS The intraobserver reproducibility was substantial for surgeon experience level (< 5 years: 0.74 vs 5–10 years: 0.69 vs 10–20 years: 0.69 vs > 20 years: 0.70) and surgical subspecialty (orthopedic spine: 0.71 vs neurosurgery: 0.69 vs other: 0.68). Furthermore, the interobserver reliability was substantial for all surgical experience groups on assessment 1 (< 5 years: 0.67 vs 5–10 years: 0.62 vs 10–20 years: 0.61 vs > 20 years: 0.62), and only surgeons with > 20 years of experience did not have substantial reliability on assessment 2 (< 5 years: 0.62 vs 5–10 years: 0.61 vs 10–20 years: 0.61 vs > 20 years: 0.59). Orthopedic spine surgeons and neurosurgeons had substantial intraobserver reproducibility on both assessment 1 (0.64 vs 0.63) and assessment 2 (0.62 vs 0.63), while other surgeons had moderate reliability on assessment 1 (0.43) and fair reliability on assessment 2 (0.36). CONCLUSIONS The international reliability and reproducibility scores for the AO Spine Upper Cervical Injury Classification System demonstrated substantial intraobserver reproducibility and interobserver reliability regardless of surgical experience and spine subspecialty. These results support the global application of this classification system