Abstract
Background
The association between idiopathic scoliosis and intrinsic abnormalities of the spinal cord are well known. MRI is the most sensitive imaging modality available to diagnose an intraspinal anomaly. The use of a routine ‘screening MRI’ prior to scoliosis correction is controversial.
Purpose
This study sought to quantify the frequency of previously unidentified cord anomalies identified by a routine pre-operative MRI, in patients planned for surgical scoliosis correction.
Methods and results
The patient group comprised 206 patients with idiopathic scoliosis who underwent deformity correction from 1998 to 2008. Of these, 20 (9.7 %) patients were diagnosed with an unexpected intraspinal anomaly (isolated syrinx-7, syrinx with Chiari malformation-4, isolated Chiari malformation-4, syrinx with tethered cord-2, split spinal cord-1, intrinsic spinal cord tumour-1, AV fistula-1) on routine pre-operative MRI. In all cases a neurosurgical opinion was sought prior to further intervention. Of the 20 patients, 11 underwent a neurosurgical procedure (de-tethering of cord, decompression of Chiari malformation, decompression of syrinx). No statistically significant difference was identified between individuals with or without a neurosurgical anomaly with respect to the age of presentation, gender, side and degree of curve.
Conclusion
The high frequency of previously unidentified cord abnormalities detected, and the frequent need for subsequent neurosurgical intervention, suggests that MRI assessment prior to deformity correction is important in the management of idiopathic scoliosis.
