Vertebral and Intraspinal Anomalies in Indian Population with Congenital Scoliosis: A Study of 119 Consecutive Patients

STUDY DESIGN: Retrospective case study by clinical and radiological data analysis. PURPOSE: To analyze different types of vertebral anomalies and the incidence of associated intraspinal anomalies in the Indian population. OVERVIEW OF LITERATURE: This is the largest study of congenital scoliosis and associated intraspinal anomalies in Indian population. Incidence of intraspinal anomaly in this series is 47% which is higher than previous literature. Hemivertebra was the most common anomaly as seen in previous studies. METHODS: A total of 119 patients with congenital scoliosis who underwent surgery between December 2006 and December 2012 were studied. Data was reviewed with medical records, plain radiographs, and magnetic resonance imaging (MRI) scans. RESULTS: Thoracolumbar curve was most common, seen in 43.6% of patients. In addition to scoliotic deformity, kyphosis was seen in 26% of patients. Failure of formation, the most common vertebral anomaly, was seen in 51.2% of patients, failure of segmentation was seen in 19.3% of patients, and there were 29.4% patients having both formation and segmentation anomalies. Hemivertebra was the most common vertebral anomaly seen in 66.3% of patients and for whom 63.2% were in thoracic spine. Intraspinal anomalies were associated with 47% of patients with congenital scoliosis. Tethered cord was the most common intraspinal abnormality and was found in 48.2% patients with intraspinal anomalies. The patients with failure of segmentation and mixed deformities were found to have a significantly higher incidence of intraspinal anomalies (65% and 57%, respectively) than those with failure of formation (34%). Out of 31 patients with kyphotic deformity 29% had intraspinal anomalies, and amongst them tethered cord was the most common anomaly seen in 66% patients. Out of 12 patients with neurocutaneous markers, 83% patients had intraspinal anomaly. CONCLUSIONS: Intraspinal anomalies were seen in 47% of patients with congenital scoliosis in the Indian population. Tethered cord was the most common intraspinal anomaly, seen in 48% cases of congenital scoliosis. Hemivertebra was seen in 66% cases and was the most common vertebral defect. Hence MRI imaging of whole spine should be done in all cases of congenital scoliosis before any surgical intervention. Special attention should be given to physical examination and visualization of any neurocutaneous markers, which are associated with a higher incidence of intraspinal anomalies; absence of a neurocutaneous marker, however, does not rule out intraspinal anomaly.