Burst fractures lead to a fracture-associated intervertebral vacuum phenomenon: a case series of 305 traumatic fractures of the thoracolumbar spine.

Purpose: Intervertebral vacuum phenomenon (IVP) is mainly seen as a sign of degenerative disc diseases. Although studies have shown that IVP also occurs after traumatic injuries to the spine, its clinical relevance in spinal fractures remains unknown. Therefore, the aim of this study was to analyse the prevalence, demographic parameters and fracture morphology in patients with fracture-associated IVP (FAVP) of the thoracolumbar spine.

Methods: In this retrospective cohort study, patients with traumatic fractures of the thoracolumbar spine who were admitted between January 2014 and December 2015 were included. CT scans were assessed for the presence of intervertebral areas of gaseous radiolucency, which were defined as IVP. Fractures were classified according to the AOSpine Thoracolumbar Spine Injury Classification System. Demographic and anamnestic data, including age, sex and trauma mechanism, were documented.

Results: A total of 201 patients with 305 fractures were included. Seventy-three patients with 98 fractures had follow-up CTs. Sixty-eight patients had IVP, of whom 46 patients had FAVP. On the follow-up CT, a significant correlation was found between A3 fractures and FAVP, while initial FAVP was significantly correlated with age and low-velocity trauma mechanisms. Initial degenerative IVP also showed a significant correlation with age.

Conclusions: FAVP occurred significantly more often in burst fractures and therefore may lead to disc degeneration due to nutritional supply disturbances via the vertebral endplate. As surgical management strategies for burst fractures are intensively discussed, the appearance of FAVP should be taken in consideration.