Unstable Thoracolumbar Injuries: Factors Affecting the Decision for Short-Segment vs Long-Segment Posterior Fixation

Abstract

Background: Factors influencing the length of spinal instrumentation have been mostly evaluated in burst fractures, receiving more attention than other unstable thoracolumbar injuries. We aimed to evaluate clinical factors affecting surgical decision-making and associated complications. Methods: This was a multicentric retrospective cohort study. Outcomes of patients with AO Spine injury classification types B2, B3, and C operated through an open posterior-only approach were analyzed. Length of instrumentation was correlated with age, type of injury, comorbidities, level of injury, neurological status, and complications. Results: Among 439 patients, 30.3% underwent short-segment fixation (SSF) and 69.7% underwent long-segment fixation (LSF). Type C injuries were treated with LSF in 89.4% of cases (P < 0.001). On multivariate analysis, age ≤39 years (OR: 2.06), AO spine type B2 (OR: 3.58), and type B3 (OR: 7.48) were statistically significant predictors for SSF, while hypertension (OR: 4.07), upper thoracic injury (OR: 9.48), midthoracic injury (OR: 6.06), and American Spinal Injury Association Impairment Scale A (OR: 3.14) were significantly associated with LSF. Patients with SSF had fewer overall complications (27.1% vs 50.9%, P < 0.001) and were less likely to develop pneumonia (6.0% vs 18.3%, P < 0.001) and urinary tract infections (6.8% vs 16.3%, P < 0.007). Conclusions: Unstable thoracolumbar injuries were mostly treated by LSF. Length of instrumentation was affected by the type of spinal injury, location of the injury, and neurological status. SSF was associated with lower rates of early complications than LSF. Clinical Relevance: The decision on the length of fixation in the surgical treatment of unstable thoracolumbar injuries is affected by different factors, and it will impact the rate of postoperative complications.