The neurologic sequelae of cervical spine facet injuries. The role of canal diameter.

Neurologic outcomes were correlated with the cervical canal diameter for 33 patients who sustained unilateral or bilateral facet fractures, dislocations, subluxations, or perch injuries during a 9-year period. Lateral roentgenograms (target distance, 72 in.) were used to measure the canal and calculate the canal-body ratio (Torg's ratio) at the level of the vertebral injury. Frankel's classification system was employed to compare initial and final neurologic function. The most important factors that determined the long-term functional results after unilateral or bilateral injuries in the cervical spine were the degree of vertebral trauma and the severity of the initial neurologic deficit. There was no correlation between the preinjury canal diameter or ratio and the severity of neurologic injury or the prognosis. Also, neurologic injuries were more common and more severe in patients with bilateral facet injuries. No patients with complete injuries had an improvement in their Frankel grade.