Halifax clamp fixation for atlanto-axial instability: C1-C3 fixation, a new technique

We present a new technique for stabilizing atlanto-axial instability and describe our series of 42 patients who presented with atlanto-axial instability and underwent C1-C3 fixation using Halifax interlaminar clamps. This is the largest reported series employing Halifax clamps for C1-C2 instability. Solid arthrodesis depends upon proper selection, positioning, and tightening of the clamp, as well as crimping the threads of the screw after placement to prevent screw backout. We included C3 in this technique based on several C1-C2 clamp failures. Over a follow-up that has ranged from 18 to 57 months (mean, 35.6 months), we achieved a 97.6% fusion rate in all 42 patients with autologous bone grafting. Patient selection, operative indications, and technical aspects involved in the use of Halifax clamps from C1-C3 with autogenous bone grafting are presented. We believe this technique provides internal fixation and is an alternative for atlanto-axial arthrodesis.