Figure 1.

A 58-year-old female (case 2) with nonunion fracture odontoid with atlantoaxial instability (a,b,c). Preoperative halo-vest traction (d) was given. Posterior instrumented C1C2 fusion was planned. Intraoperative navigation (e,f) helped in accurate localization of entry point and in ascertaining trajectory and dimensions of pedicle screws. Postoperative radiographs (g,h) showed satisfactory alignment. Ten-month follow-up CT scan (i,j) showed good placement of C1 and C2 pedicle screw and union in satisfactory alignment (k,l).