Surgical Management of Old Lower Cervical Dislocations With Locked Facet.

Study Design: Prospective study. Objective: To evaluate the role of the canal and vertebrae sagittal diameter (C/V) ratio in the treatment of old dislocations of the lower cervical spine. Summary of Background Data: Few studies have reported the management of old dislocations of the lower cervical spine. Conservative treatments including the use of a Halo vest, neck brace, and prolonged traction have been problematic. Operative treatment consisted of a primary or staged reduction and fusion using an anterior, posterior, or combined approach. Methods: Fourteen consecutive patients with old dislocations of the lower cervical spine were included in this series. The preoperative C/V value was calculated based on the measurement on the neutral sagittal computed tomography at the most narrow place of the dislocated segments. Closed reduction was attempted in 9 patients with moderate stenosis (C/V>0.5). Five patients with severe stenosis (C/V≤0.5) were treated with a primary combined anterior and posterior operation. Patient’s radiographic information, pain, and neurological function were assessed and recorded before and after surgery. Results: Closed reduction followed by anterior cervical discectomy and fusion was performed in 3 of 9 patients with moderate stenosis. Eleven patients underwent circumferential release, posterior reduction, and fixation followed by anterior fusion. No severe complications were found. The average operative time was 138±43 minutes. The average blood loss was 239±140 mL. The postoperative C/V value was significantly increased. The neurological status improved at least one grade in all 13 neurologically impaired cases except for 2 who had complete spinal cord injuries. Bony fusion was obtained in all patients at 1-year follow-up. Conclusions: The C/V value plays an important role in determining surgical solutions for old lower cervical dislocations with locked facets. Favorable clinical outcomes can be achieved using closed reduction and surgical procedures with anterior or anterior plus posterior approaches.