Anterior instrumentation for traumatic C1-C2 instability.

STUDY

DESIGN

Technical note, case report. and review of literature.

OBJECTIVE

Description of anterior transarticular internal fixation for traumatic C1-C2 instability.

SUMMARY OF BACKGROUND DATA: The currently effective posterior approaches for instrumentation of the C1-C2 junction require considerable soft tissue dissection and prone patient positioning. Some medical and anatomic conditions restrict the posterior approach.

MATERIALS AND

METHODS

An odontoid screw and anterior transarticular C1-C2 screws were used to instrument an unstable injury at this junction. The lesion consisted of a type II dens fracture and C1 ring disruption. Two high-quality fluoroscopy machines, a radiolucent OSI fracture table, and the Synframe (Synthes, Paoli, PA) retraction system are used for this procedure. The implant of choice is the 4.0-mm cannulated titanium screw.

RESULTS

At 4-month follow-up, successful stabilization without failure of hardware is documented. The patient's neurologic status is stable, with a minor residual left upper extremity motor deficit. The patient has restricted C-spine rotation but no neck pain with movement.

CONCLUSION

Anterior stabilization through a standard Smith-Robinson approach of the C1-C2 junction with screws into the odontoid and the lateral masses of C1 is effective. Supine positioning and minimal soft tissue dissection are advantages of this method over standard posterior transarticular instrumentation. Knowledge of the local anatomy, strict adherence to the operative protocol, and high-quality fluoroscopy avoid potential surgical complications.