Correlation between disc injury and parameters of vertebral body damage in patients with neurologically intact thoracolumbar bust fractures

Abstract

Objective To assess the disc injury in neurologically intact thoracolumbar bust fractures and to evaluate the correlation between the severity of disc injury and the parameters of vertebral body damage as as to formulate radiologic index for further MRI examination. Methods A retrospective case series review was made on 22 patients (44 discs) with thoracolumbar burst fractures without neurologic deficit treated from January 2015 to December 2015. Vertebral level involved was from T11-L2. There were 12 males and 10 females, with the mean age of 47.9 years (range, 43-60 years). MRI were used to evaluate the severity of disc injury. Among the 44 discs, 18 were Grade 0, 11 were Grade 1, 12 were Grade 2, and three were Grade 3. Then patients with Grade 0 and 1 were taken as disc intact group and other 12 patients disc rupture group. Vertebral wedge angle, local kyphosis angle, anterior and posterior vertebral body height and canal compromise were measured on CT to determine the damage of fracture. Spearman correlation coefficient was used to analyze the correlation between the severity of disc injury and the parameters of vertebral body damage, and receiver operative curve (ROC) was used to assess the effectiveness of these indexes in predicting disc injury. Results Vertebral wedge angle and anterior/posterior vertebral body height ratio were correlated with the severity of superadjacent disc injury (P 0.05). Threshold of canal compromise, vertebral wedge angle and anterior/posterior vertebral body height ratio were 21%, 15.4°, and 0.69 respectively. Conclusions Vertebral wedge angle and anterior/posterior vertebral body hight ratio are correlated with the severity of superadjacent disc injury. Canal compromise>21%, VWA>15°and anterior/posterior vertebral body height ratio > 0.69 may be the practice preferences of indications for ordering a MRI in patients with neurologically intact thoracolumbar bust fractures. Key words: Thoracic vertebrae; Lumbar vertebrae; Intervertebral disc; Magnetic resonance imaging; Neurologically intact