Significance of thoracolumbar spinal canal dimensions in prediction of neurologic injury in patients with burst fractures

ABSTRACT

The relation between the spinal canal dimensions and its association with neurologic sequelae after cervical spine injuries has been established. A similar relation at the thoracolumbar spine is debated in the literature. The aim of this work is to determine the relation between the spinal canal dimensions and their association with neurologic sequale after thoracolumbar burst fractures. In a prospective study between January 1999 and December 2001, 48 patients with thoracolumbar burst fractures [T11-L2] 22 with neurologic deficit and 26 without neurologic deficit were included in our study. There were 30 males and 18 females, their age ranged from 18 to 62 years with a mean age of 37 years. Computed tomographic [CT] scans were done for all the patients to evaluate the pattern of the fracture and to measure the sagittal, the transverse diameters and the surface areas of the spinal canal at the level of injury, as well as one level above and one level below the fracture level. The type of neurological deficit in all patients was scored on the scale of Frankel et al 1969. All the patients with burst fractures of the thoracolumbar junction, with and without neurologic deficit, were compared in sagittal diameter, transverse diameter, sagittal-to-transverse diameter ratio and cross sectional area [CSA]. Statistical analysis was performed using Student s t-test. We found that the ratio of sagittal-to-transverse diameter at the level of injury was significantly smaller in patients with neurological deficit than those without a neurologic deficit. The mean transverse diameter at the level of injury was significantly larger in patients with neurological deficit than in the neurologically intact patients. The surface area of the canal at the level of the injury was significantly smaller in patients with neurological deficit than in those without a deficit. There was no significant statistical relation between spinal canal measurements above and below the level of injury with the neurologic deficit. We concluded that. There were no anatomic factors at the thoracolumbar junction that predisposed to neurologic injury after burst fracture, however the shape and the size of the canal after injury were predictive of neurologic deficit