Prediction of stability of cervical spine fracture managed in the halo vest and indications for surgical intervention.

A retrospective study was made of 173 cases of acute cervical spine injury with halo vest management to compare initial injury features with outcome. The object was to determine whether a mathematical model could be developed enabling a prediction to be made at the time of the initial assessment as to the probability of success or failure of conservative management using the halo vest alone, and thus perhaps avoid lengthy, unsuccessful treatment. Patients with facet joint dislocation were found to form a distinct subgroup of the injury population. Of the 70 patients in this subgroup, 44% achieved stability with the halo vest alone, but half of these had a "poor anatomical result." No mathematical model or associated injury features could be found to assist in the outcome prediction in this subgroup. Of the 103 patients without facet joint dislocation, 70% achieved stability with the vest alone and over 75% of these had a "good anatomical result." A useful model of outcome prediction was found for this subgroup by logistic regression analysis; the two most important predictors in the model were the amount of subluxation and the degree of angulation in the sagittal plane.