Use of Axial and Subaxial Translaminar Screws in the Management of Upper Cervical Spinal Instability in Children

Abstract

INTRODUCTION: The management of upper cervical spinal instability in children represents a technical challenge. A number of wiring techniques followed by halo orthosis have been applied; however, they have been associated with a high nonunion rate and poor tolerance for the halo. Screw fixation allows more rigid fixation, but it is technically demanding and associated with vertebral artery injuries. Recently, C2 translaminar screws have been added to the armamentarium of the pediatric spine surgeon as a safe and efficacious method of fixation. However, subaxial translaminar screws have not been described in children. We describe axial and subaxial translaminar screw fixation in six pediatric patients. METHODS: Six pediatric patients with the diagnosis of upper cervical spinal instability required surgical fixation (age, 19 mo–10 yr; sex, three males and three females; follow-up duration, 2–18 mo). The etiologies were trauma (n = 2), os odontoideum/os terminale (n = 2), and hypoplastic dens (n = 2). All patients underwent axial and/or subaxial translaminar screw insertion. Iliac crest bone graft was used for fusion in three patients, and BMP and cancellous morselized allograft was used in three patients. A rigid cervical collar was applied postoperatively in all cases for 12 weeks. RESULTS: All patients had postoperative computed tomographic scans. Subaxial translaminar screws were placed at C3 and in the upper thoracic spine. Hybrid constructs (C2 translaminar screw plus C2 pars screw) were incorporated in three patients. There were no perioperative complications related to translaminar screw placement. No patients were found to have a breach of the ventral laminar cortex. All patients with at least a 3-month follow-up achieved solid fusion. CONCLUSION: This represents the only series of pediatric patients treated with axial and subaxial translaminar screws to date. Axial and subaxial translaminar screw fixation is a viable option for upper cervical spinal fusion in children. The technique is safe and results in high fusion rates.