ATLANTOAXIAL ARTHRODESIS USING HALIFAX INTERLAMINAR CLAMPS REINFORCEDBY HALO VEST IMMOBILIZATION - A LONG-TERM FOLLOW-UP EXPERIENCE

THIRTY-TWO PATIENTS WHO underwent atlantoaxial arthrodesis using Halif ax interlaminar clamps and halo vests between January 1989 and Decembe r 1992 were reviewed. The atlantoaxial instabilities were related to t rauma in 16 patients, including 14 patients with unstable odontoid fra ctures, 1 patient with a complex C2 fracture, and 1 patient with a dis rupted transverse ligament. Of the other 16 patients, whose atlantoaxi al instabilities were nontraumatic in origin, 9 had instabilities that were secondary to rheumatoid arthritis, 1 had instability that was se condary to tuberculous infection, and 6 had instabilities that were ca used by os odontoideum. The patients were followed postoperatively wit h lateral cervical radiographs for an average of 37 months (range, 16- 59 mo). Solid atlantoaxial arthrodeses were achieved in all (100%) of these 32 patients after 32 to 111 days (average, 84.5 d) of halo immob ilization, indicating atlantoaxial arthrodeses can be reasonably antic ipated when Halifax interlaminar clamps with autogenous iliac bone gra fting are reinforced by halo vest immobilization for 3 months.