Craniovertebral junction anomalies and C1-C2 instability resulting in myelopathy have been well described in the literature on mucopolysaccharidosis IV (MPS-IV). Spinal involvement in MPS-IV patients, with neurological impairment, other than atlanto-axial instability and thoracolumbar kyphosis, has been scarcely mentioned in the literature.
Retrospective clinical and radiologic review of the medical records and imaging studies of 4 individuals with Morquio A syndrome, who had undergone decompression and fusion of the cervicothoracic spine for myelopathy secondary to cervicothoracic stenosis between 1990 and 2009. Data regarding the presence of kyphosis at the cervicothoracic and upper thoracic spine, and neurological symptoms and signs were obtained.
There were 3 girls and 1 boy with an average age of 5 years and 11 months at presentation with neurological symptoms. Half of the patients had previously undergone occipitocervical fusion for atlanto-axial instability, whereas the other half were noted to have spinal cord compression at both the upper cervical and cervicothoracic regions, and underwent decompression and fusion at both levels concomitantly. All patients showed postoperative neurological improvement. All patients presented with the classical Morquio syndrome vertebral morphology. Cervicothoracic kyphosis was found in all of our patients in a varying severity (10 to 35 degrees). Levels of stenosis were similar in 3 patients, C7-T2; and occurred at a lower spinal level, T1-T4, in the remaining patient. Posterior disk bulging and thecal sac indentation were found in all 4 patients.
Neurological problems secondary to progressive kyphosis and stenosis at the cervicothoracic and upper thoracic spine are seen in children with Morquio syndrome. Early detection with a careful neurological assessment, whole spine MR imaging, and appropriate surgical treatment can prevent permanent neurological sequelae.