A retrospective study evaluating the correlation between the severity of intervertebral disc injury and the anteroposterior type of thoracolumbar vertebral fractures

OBJECTIVE: To evaluate the correlation between the severity of intervertebral disc injury and the anteroposterior type of thoracolumbar vertebral fractures. METHODS: Fifty-six cases of thoracolumbar vertebral fractures treated in our trauma center from October 2012 to October 2013 were included in this study. The fractures were classified by the anteroposterior classification, whereas the severity of intervertebral disc injury was evaluated using magnetic resonance imaging. The Spearman correlation coefficient was used to analyze the correlation between the severity of intervertebral disc injury and the anteroposterior type of thoracolumbar fractures, whereas a χ(2) test was adopted to measure the variability between different fracture types and upper and lower adjacent disc injuries. RESULTS: The Spearman correlation coefficients between fracture types and the severity of the upper and lower adjacent disc injuries were 0.739 (P(U)<0.001) and 0.368 (P(L)=0.005), respectively. It means that the more complex Arbeitsgemeinschaft für Osteosynthesefragen (AO) classifications are the disc injury is more severe. There was also a significant difference in the severity of injury between the upper and lower adjacent discs near the fractured vertebrae (p<0.001). CONCLUSIONS: In thoracolumbar spinal fractures, the severity of the adjacent intervertebral disc injury is positively correlated with the anteroposterior fracture type. The injury primarily involves intervertebral discs near the fractured end plate, with more frequent and severe injuries observed in the upper than in the lower discs. The presence of intervertebral disc injury, along with its severity, may provide useful information during the clinical decision-making process.