Sublaminar Wiring Highly effective for Atlanto-Axial Dislocation in Morquio Syndrome, Case Report
A recent case report highlights C1–C2 sublaminar wiring as a safe, highly effective treatment for atlanto-axial dislocation in Morquio syndrome when anomalous vascular anatomy makes modern screw-based fixation too dangerous. This traditional approach successfully stabilized the spine and reversed progressive myelopathy in a pediatric patient, proving its essential value as a surgical rescue option.
These findings of the case report are published in the Journal of Spinal Surgery by Dalvin Thomas and colleagues.
A 14-year-old boy with Morquio syndrome (MPS IV-A) presented with progressive gait instability, neck pain, hyperreflexia, mild lower-limb proprioceptive deficits, and a positive Romberg’s sign. Dynamic cervical radiographs and MRI revealed severe C1–C2 joint instability, spinal cord compression, and canal stenosis. A preoperative CT angiogram identified an anomalous left vertebral artery crossing the posterior aspect of the C1–C2 joint, which presented a high risk of catastrophic hemorrhage during screw placement. Consequently, the surgical approach was modified from screw fixation to C1–C2 sublaminar wiring. Following a midline posterior exposure, sublaminar wires were passed beneath the C1 and C2 laminae using the Medtronic Atlas Cable system. Joint reduction was achieved via cable tensioning and secured with a cable crimp. To promote solid osseous fusion, a local bone graft from the resected C2 spinous process was applied alongside osteoconductive hydroxyapatite crystals.
The mechanical instability in the case stems from the ligamentous laxity and odontoid hypoplasia characteristic of Morquio syndrome, which subjects the cervical spinal cord to repetitive, motion-induced compression. Although rigid screw-rod constructs are the modern standard for stabilization, abnormal vertebral artery pathways and dysplastic bone structures make screw dissection highly hazardous. Sublaminar wiring circumvents these anatomical barriers by securing the posterior elements without drilling into the pedicles or lateral masses. Tensioning the cables creates a posterior tension band that reduces the dislocation and compresses the joint surfaces, while the combination of a decorticated C1–C2 bed, local autograft, and hydroxyapatite crystals provides the necessary mechanical and osteoconductive scaffolding to accelerate stable, long-term bone fusion.
Clinical Implications
Although modern screw-rod constructs are the standard of care, sublaminar wiring remains a vital alternative. It eliminates the risk of vertebral artery injury and serves as an excellent primary or rescue method in patients with dysplastic bone structures or anomalous vascular paths.
Reference
Thomas, D., Abdullah, M., Menon, S. K., & Sreekesh, P. V. (2026). Surgical management of an atlanto-axial dislocation in Morquio syndrome with C1–C2 sublaminar wiring. Journal of Spinal Surgery, 13(2), 117-120.
