Stable reconstruction using halo vest for unstable upper cervical spine and occipitocervical instability

Abstract

Upper cervical or occipitocervical disorders such as rheumatoid arthritis present as atlantoaxial subluxation, vertical subluxation of the axis, and subaxial subluxation, which produce myelopathy and severe pain. In such cases, occipitocervical reconstruction surgery may be indicated, and several reports have described reduction of subluxation by fixing the halo vest before this surgery. The purpose of this study was to evaluate the efficacy of using the halo vest before the surgery for unstable upper cervical spine and for occipitocervical instability. Twenty-eight patients (9 men and 19 women; mean age, 61.8 years at surgery) who presented with atlantoaxial or occipitocervical fusion were studied. In all cases, the halo vest was fixed in the conscious condition, and subluxation was reduced before the surgery. The mean follow-up period was 45 months. Roentgenologic measurement and clinical evaluation were performed before the surgery and at the final follow-up. Using the halo vest resulted in significant reductions in the atlantodental interval, the space available for the spinal cord, and the Ranawat value (p < 0.05), and these were maintained until the final follow-up. The mean Japanese Orthopedic Association score significantly improved from 9.5 before surgery to 12.2 at the final follow-up (p = 0.01). Nineteen cases (68%) improved by more than 1 grade by Ranawat's classification after surgery and 16 cases (57%) maintained the same at the follow-up visit. Conscious preoperative reduction using the halo vest for occipitocervical disorders is a useful and safe technique.