Thecal sac injury secondary to burst fractures of the thoracolumbar and lumbar spine with compromise of the posterior vertebral body wall, and its association with the AOSpine Classification System variables

AbSTRAcT Introduction: Fractures of the thoracolumbar spine can trigger thecal sac injuries due to the impingement of the cauda equina between bone fragments. Objectives: To carry out a retrospective analysis of clinical and radiological variables, the AOSpine Classification System and the possibility of secondary thecal sac injury in a series of thoracolumbar burst fractures treated at our center. Materials and methods: A retrospective, observational study of a series of patients with thoracolumbar fractures with compromise of the posterior vertebral body wall, who underwent surgery at our center between January 2012 and December 2017. Results: Forty-six patients were included, 16 of which had secondary thecal sac injury. The differences in the variables—percentage of spinal canal involvement, interpedicular distance, angle of the retropulsed fragment, neurological deficit and type C fractures—were statistically significant according to the comparison made with the presence or absence of thecal sac injury (p = 0.046, p = 0.007, p = 0.046, p = 0.004, p = 0,001 respectively). conclusions: This study suggests that traumatic thecal sac injury could be suspected when managing burst fractures with prominent fragments in the posterior vertebral body wall, acute angle of the retropulsed fragment, severe compression of the spinal canal, wide interpedicular distance, neurological deficit and fracture displacement (fracture type C according to the AOSpine Classification System).