Surgical Management of an Atlanto-axial Dislocation in Morquio Syndrome with C1–C2 Sublaminar Wiring

Morquio syndrome (Mucopolysaccharidosis Type IV-A) is a rare lysosomal storage disorder characterized by severe skeletal dysplasias. One of its most critical complications is atlanto-axial dislocation (AAD) secondary to odontoid hypoplasia and ligamentous laxity, leading to potential spinal cord compression and myelopathy. The standard of care for this abnormality is posterior cervical decompression and fusion. We present the case of a 14-year-old boy diagnosed with Morquio syndrome who presented with progressive gait instability, neck pain, and signs of upper motor neuron involvement consistent with cervical myelopathy. Radiological evaluation, including dynamic X-rays, computed tomography, and magnetic resonance imaging of the cervical spine, confirmed AAD with significant stenosis of the spinal canal at the C1–C2 level. The patient underwent surgical stabilization via a posterior approach. A C1–C2 arthrodesis was performed using a sublaminar wiring technique with a resected part of the C2 spinous process acting as a graft. Postoperatively, the patient was immobilized in a rigid cervical collar. At his follow-up, he showed moderate neurological improvement with resolution of myelopathic signs. Radiographs demonstrated a stable reduction of the dislocation and ongoing bony fusion across the C1–C2 joint. Although modern posterior fixation techniques involving C1 lateral mass and C2 pedicle screws are now the gold standard for AAD, this case demonstrates that sublaminar wiring remains a viable and effective surgical option in selected patients with Morquio syndrome. This technique is particularly useful in cases with challenging anatomy, resource limitations, or when screw placement is high-risk. Sublaminar wiring, when performed properly, can achieve stable fusion and good neurological outcomes.