Epidemiology, AO morphology, and diagnostic delay of discontinuous thoracolumbar fractures: A 10-year single-center...

Discontinuous thoracolumbar fractures are uncommon but clinically important injuries that may be overlooked during the initial evaluation. Their epidemiological features, morphological characteristics, and patterns of diagnosis remain incompletely defined.

We retrospectively screened 4394 patients with spinal fractures treated at a single center between January 2016 and December 2025. After predefined exclusions, 186 patients with discontinuous thoracolumbar fractures were included. Baseline demographic and injury characteristics were compared with those of patients with single-level fractures. Within the discontinuous fracture cohort, we analyzed the number of fractured levels, regional distribution, number of intact vertebrae between fractures, vertebral-level involvement, AO Spine morphology according to fracture order, patient-level AO combination patterns, and time to diagnosis of initially missed lesions.

Discontinuous thoracolumbar fractures accounted for 4.2% of all spinal fractures and 64.4% of multilevel vertebral fractures. Two-level injuries were most common (49.5%), followed by three-level (35.5%) and ≥ 4-level patterns (15.1%). All cases involved the lumbar region, and 72.6% had one or two intact vertebrae between the injured levels. Compared with single-level fractures, discontinuous fractures were more frequently associated with falls from height, concomitant injuries, and polytrauma. The fracture burden was concentrated at the thoracolumbar junction and lower lumbar spine, and L1 was the most common site of the most severe injury. AO morphology exhibited a severity gradient: the most severely injured vertebra was usually classified as A3, A4, or B2, whereas subsequent injured vertebrae were predominantly classified as A1. At the patient level, A-only combinations were most common (50.5%), followed by A + B combinations with a single B-type level (38.7%); C-type injuries were rare (1.1%). The second fracture was initially missed in 44.1% of cases; cumulative recognition increased to 81.7% within 24 h and 94.6% within 48 h.

Discontinuous thoracolumbar fractures have distinct epidemiological and morphological characteristics, including clustering at the thoracolumbar-lumbar junction, a predominance of compression-based AO combinations, and a high rate of initially missed diagnoses. These findings support systematic whole-spine assessment and careful imaging review in patients who sustain high-energy spinal trauma.