odontoid screwvia anterolateral approach (preserves rotation motion!) - wire pin inserted under fluoroscopy is replaced by lag screws (1 or 2 screws have same success); high fusion rates (87-100%)* if performed during first 6 weeks after fracture – odontoid screw works best if placed early! see also p. Op210 >>
*fusion rates in elderly may be as low as 60% (same as with halo) – age is important factor but not all studies agree with that (plus, fibrous union with radiographic stability may be a suitable outcome in elderly patients)
contraindicated if transverse ligament is disrupted.
look at apical ligament before surgery (if calcified*, aseptic necrosis will happen and odontoid screw will not work).
*distal dens blood supply is coming through apical ligament
difficult if patient has prominent chest (hard to achieve angle).