Cervical crossing laminar screws: early clinical results and complications.

OBJECTIVE: C2 crossing laminar screws are a new technique for axis fixation with a purported lower risk for neurological or vascular injury. However, to date, few clinical series on this technique have appeared in the peer-reviewed literature. This report describes our initial clinical experience and complications using this new spinal fixation technique.

METHODS: Thirty patients underwent high cervical intralaminar fixation with crossing intralaminar screws. Indications for surgery included occiput to cervical fixation for basilar invagination in six patients, fixation for atlantoaxial subluxation or trauma in six patients, cervical swan neck deformity in four patients, and laminectomy and instrumented fusion for cervical stenosis in 14 patients. Two cases involved C3 fixation resulting from congenital anomalies. A total of 59 screws were placed, and the patients were assessed both clinically and radiographically with postoperative computed tomographic scans.

RESULTS: There were no intraoperative complications and no cases of neurological worsening or vascular injury from hardware placement. One patient reported local neck pain resulting from hardware prominence. Computed tomographic scans demonstrated a partial dorsal laminar breach in 11 patients and violation of the spinal canal in one patient. None of these resulted in neurological symptoms. Early hardware fractures were observed in two patients.

CONCLUSION: Crossing C2 laminar screws provide the surgeon with an expanded armamentarium for fixation in the high cervical spine. This technique is straightforward and easily adopted. However, the unique position of the screw heads may result in increased stress and strain on the intralaminar screws. Thus, larger diameter screws or additional fixation points at adjacent levels are recommended.