Journal of neurosurgery. Spine
-
Multicenter Study Clinical Trial
Stabilization of the atlantoaxial complex via C-1 lateral mass and C-2 pedicle screw fixation in a multicenter clinical experience in 102 patients: modification of the Harms and Goel techniques.
Stabilization of the atlantoaxial complex has proven to be very challenging. Because of the high mobility of the C1-2 motion segment, fusion rates at this level have been substantially lower than those at the subaxial spine. The set of potential surgical interventions is limited by the anatomy of this region. In 2001 Jürgen Harms described a novel technique for individual fixation of the C-1 lateral mass and the C-2 pedicle by using polyaxial screws and rods. This method has been shown to confer excellent stability in biomechanical studies. Cadaveric and radiographic analyses have indicated that it is safe with respect to osseous and vascular anatomy. Clinical outcome studies and fusion rates have been limited to small case series thus far. The authors reviewed the multicenter experience with 102 patients undergoing C1-2 fusion via the polyaxial screw/rod technique. They also describe a modification to the Harms technique. ⋯ Fusion of C1-2 according to the Harms technique is a safe and effective treatment modality. It is suitable for a wide variety of fracture patterns, congenital abnormalities, or other causes of atlantoaxial instability. Modification of the Harms technique with distraction and placement of an allograft spacer in the joint space may restore C1-2 height and enhance radiographic detection of fusion by demonstrating a graft-bone interface on plain x-ray films, which is easier to visualize than the C1-2 joint.