Is the pelvis "organ protective" in pelvic and spine trauma? A database study of spine and pelvic combination injuries.

Abstract

Traumatic spine fractures often occur with multisystem injuries. Pelvic and transverse process (TP) fractures have been linked to visceral trauma, but whether the pelvis behaves as an "organ protective" structure in spine injury is unclear. To determine how concomitant pelvic fractures and TP fracture burden influence visceral injury patterns in patients with spinal fractures. This retrospective cohort included adult trauma patients with CT-confirmed spinal fractures at a single Level I trauma center (2015-2023). Patients were grouped into spine-only or spine-plus-pelvic fracture groups. Demographics, mechanism, TP characteristics, and visceral injuries (thoracic, abdominal, neurologic) were recorded. Liver, spleen, and kidney injuries were graded using the American Association for the Surgery of Trauma criteria, and a Visceral Injury Complexity Score (VICS) was calculated. Bivariate analyses and multivariable Poisson regression assessed associations between pelvic injury and TP fracture count with visceral injury burden and organ-specific severity. Among 154 patients (86 spine only, 68 spine plus pelvic), overall visceral (92.5% vs 70.9%) and abdominal injuries (85.1% vs 50.9%) were more common in spine only trauma, which also showed higher VICS and spleen injury grades. Pelvic injury independently predicted fewer abdominal injuries and lower liver, spleen, and composite organ injury severity, whereas increasing TP fracture count predicted higher total visceral, thoracic, and neurologic injury counts and greater spleen, kidney, and composite organ injury severity. In spine trauma, pelvic fractures were associated with reduced abdominal organ injury burden, while greater TP fracture burden identified patients with more extensive multisystem trauma, supporting a dual role of the pelvis as both an injury marker and a potential organ protective structure.