Percutaneous navigation-assisted versus open posterior fixation for thoracolumbar fractures in ankylosing spinal diseases: a single-institution 15-year cohort analysis.

OBJECTIVE: Ankylosing spinal pathologies including ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) predispose patients to long bone-type unstable fractures after even low-velocity mechanisms of injury. These fractures often require long-segment pedicle screw fixation. Patients with AS and DISH tend to be elderly and have significant comorbidity burdens, emphasizing the importance of minimizing surgical complications. Therefore, the authors investigated outcomes of patients undergoing percutaneous minimally invasive (MIS) pedicle screw fixation versus traditional open pedicle screw fixation with arthrodesis. METHODS: This study was a retrospective cohort analysis of patients undergoing posterior fixation surgery for AS and DISH thoracolumbar fractures from 2010 to 2025 at a tertiary academic level 1 trauma center. Use of MIS or open techniques was determined according to surgeon preference. Intraoperative, in-hospital, 90-day, and 1-year outcomes and variables were evaluated for both groups. The initial univariate analysis was performed using the Wilcoxon rank-sum test for continuous variables and Fisher's exact test for categorical variables. Multivariable linear regression analysis was performed for continuous variables, while logistic regression analysis was performed for categorical variables. RESULTS: A total of 98 patients underwent spinal fixation for AS and DISH thoracolumbar fractures, including 73 undergoing MIS fixation and 25 undergoing open fixation with arthrodesis. Patients undergoing MIS fixation had greater Charlson Comorbidity Index scores. MIS fixation resulted in significantly lower estimated blood loss (EBL) and intraoperative transfusion volumes. No significant differences were found between approaches in terms of operative time, length of stay, 90-day complications, and 1-year reoperations. CONCLUSIONS: MIS fixation for patients with AS and DISH thoracolumbar fractures is feasible, with similar long-term outcomes to traditional open fixation with arthrodesis. Additionally, the MIS approach was associated with lower EBL and transfusion requirements despite these patients being more ill, which is vitally important in the already medically frail and older AS and DISH populations.