Long-term outcomes after surgery for subaxial cervical spine injuries in octogenarians, a matched controlled analysis

Introduction: Spinal fusion surgeries have been increasing worldwide due to a rise in aging population and advances in surgical techniques and anesthesia. An increasing life expectancy has necessitated changes in various medical disciplines to effectively address the healthcare needs of the elderly. Although surgical treatment for subaxial cervical fractures in octogenarians is common practice, the associated outcomes have been poorly described. Identifying risk factors that predict outcomes can affect decision-making and increase the safety of surgical interventions in older people. We aim to identify the differences in and predictors of surgical outcomes between octogenarians and a matched cohort of younger patients with subaxial cervical spine injuries.

Methods: Eligible for inclusion were all patients surgically treated between 2006 and 2018, with either anterior or posterior fixation for subaxial cervical spine injuries at the study center. A cohort of octogenarians was identified and matched 1:1 to a corresponding cohort of younger adults based on the American Spinal Cord Injury Association (ASIA) Impairment Scale (AIS) at admission, surgical approach and number of fused levels.

Results: Fifty-four patients were included in each of the octogenarian and younger groups (median age: 84.0 vs. 38.5). Surgery was performed at a median of 2 days from the cervical trauma in both groups. There were no significant differences in estimated blood loss (p=0.403) or operative time (p=0.625). While the risks for surgical complications, including dural tears and wound infections, were similar between groups, the risks of postoperative medical complications, including respiratory or urinary tract infections, were significantly higher among the elderly (p < 0.001). Screw loosening occurred more frequently in the elderly (p=0.027), however there were no significant differences between groups in terms of revision surgeries (p=0.495). Short- and long-term neurological outcomes (AIS) did not significantly differ between groups (p=0.860 and p=0.775). The 30 and 90-day mortality rates were significantly higher among the elderly (19% vs. 2%; p=0.004 and 28% vs. 2%; p< 0.001).

Conclusion : Octogenarians with comorbidities were more susceptible to postoperative complications such as postoperative infections, explaining the increased short-term mortality in this group.