Management of post-traumatic cervical spine instability: operative fusion versus halo vest immobilization. Analysis of 49 cases.

A 5-year retrospective analysis was conducted for all cervical spine fractures associated with neurologic deficit initially treated at the University of Michigan Hospitals. Forty-nine cases of lower cervical spine fracture (C3-C7) were reviewed. Twenty-eight patients underwent early operative fusion followed by immobilization with either halo vests, or hard cervical collars, and 20 patients were initially immobilized in halo vests only. One patient refused treatment and was kept in a hard cervical collar. The average period of immobilization was 3 months. Eight patients in the halo vest group demonstrated radiographic evidence of spinal instability following immobilization (40%). Five of these eight patients subsequently required operative stabilization. Two of these five suffered progression of neurologic deficit secondary to loss of reduction while immobilized. Spinal instability occurred in two of the 28 patients initially fused (7%) (p less than 0.01), and in the patient treated in a collar. The findings indicate: 1) the halo vest does not protect patients with cervical instability from neurological injury, nor does it absolutely immobilize the cervical spine; 2) surgery may be required to provide spinal stability, even after a 3-month orthotic treatment period; and 3) there appears to be an increased rate of spinal stability with fusion and immobilization versus immobilization alone.