Treatment planning in severe scoliosis: the role of MRI.

The use of magnetic resonance imaging (MRI) in the preoperative investigation of children with idiopathic scoliosis is controversial. Syringomyelia and other intraspinal lesions may be risk factors for neurological injury during surgical correction. Our purpose was to investigate whether pathology of the neuraxis is associated with scoliosis and to detect lesions which may threaten neurological sequelae during distraction and instrumented correction. We obtained T1- and T2-weighted images of 40 children (28 girls, 12 boys), mean age 12.7 years with severe idiopathic scoliosis (Cobb angle 50-70 degrees) obtained in coronal, sagittal and axial planes from the posterior cranial fossa to the sacrum, and these were assessed by two neuroradiologists and an orthopaedic surgeon prior to further treatment planning. Abnormalities of the neuraxis were found in 24 patients (60%); five (12%) had two or more lesions. No abnormalities of the neuraxis were found in 16 patients (40%). There were 15 patients (38%) with intraspinal abnormalities who deteriorated clinically and nine (22%) who showed no clinical changes. We transferred 16 patients (40%) from the orthopaedic to the neurosurgical department for further assessment. Our results suggest that one should investigate the neuraxis with MRI before contemplating orthopaedic surgical correction of severe idiopathic scoliosis, because the findings may lead to a change of procedure.