Traumatic Spondylolisthesis Of The Axis

Background There is ambiguity concerning the nomenclature and classification of the traumatic spondylolisthesis of the Axis(TSA).The criteria of Stability, The optimal therapy, The respective indications for operative and conservative treatment, The Surgical technique over the therapeutical concept leading to optimal functional results for the TSA are still controversial, and there is a argument between the rigid and the non-rigid external fixation of method of conservative treatment. Objective To explore the classification and the choice of treatment for TSA, to make the treatment of TSA individual, regular, reasonable and standard. Methods Twenty-five Patients of AST were studied from 1991 to 2003, which all had radiological films at admission. These materials were analyzed, among which 12 cases by comparison of pre-post operation, 13 case by conservative treatment, based on Roy-Camille's method. The stability was assessed by the Francis and Coric et al's crieterias. According to the classification of Levine-Edwards, cases were divided.Surgical technique was mainly anterior fusion and bone graft and internal plate fixation between C2-C3.Conservativetreatment had the rigid and non-rigid external fixation. Results Radiological. The mean AT in the 25 patients at admission was 3.7 mm (0 to 8 mm), the mean RA was 9.7 (-7 to +25), the gap between fragments was not measured . 16 fractures were considered unstable and 9 stable . 4 cases were divided into Type I, 19 Type 11(76%), 2Type Ha , no Type III. Of the 14 cases investigated by CT, ten were asymmetrical, of which seven were unstable, four were symmetrical. In the conservative treatment, five were treated by non-rigid external fixation, seven were rigid external fixation. Clinical results were all very good . The radiological result, eight cases were considered good, 1 fair, 3 no comparison. Operation treatment, 10 very good, 1 fair , 2 poor. Conclusions. The definition of TSA is that the fracture line must cross the arch of axis on the side, on the opposite side may involve the vertebral body of the axis . The fracture are usually asymmetrical, and almost always bilateral, because of the mechanism of rotation as well as violent extension or lateral flexion forces. CT, MRI should routinely be the means of diagnosis. Levine-Edwards classification will be expanded by the rotation and extension-distraction forces for the injury mechanism. The sorts of criterias of stability are unlikely reliable, ought to combine with results of dynamic radiograghs and cervical traction for deciding. Themajority of TSA responds to a conservative treatment, according to the stability, to decide whether the external fixation is non-rigid or not. The indications of operation should be strictly controled. Type II cases with no-effect on conservative treatment are recommended operation. The anterior and posterior approaches of surgery respectively have merits . providing a guideline diagram of the remedy.