The etiology of congenital scoliosis: genetic vs. environmental—a report of three monozygotic twin cases

Abstract

To describe the presence of congenital scoliosis in a genetically identical population as it relates to the possible genetic vs. environmental etiologic factors. The authors describe three cases of congenital scoliosis in monozygotic twins. The first pair includes two 4-year-old girls presenting with mirror curves, one of whom had an associated stage I Chiari malformation. The second pair is a 4-year-old girl who presented with thoracic scoliosis, a T10-11 hemivertebra, and multilevel failure of segmentation in the lumbar spine whose identical sibling is unaffected. The third pair includes a 4-month-old boy with T9 and L4 hemivertebra whose brother is also unaffected. All three cases were managed conservatively with observation and remained asymptomatic throughout the duration of follow-up. There were no associations with extraspinal deformities, although one patient presented with concomitant type I Chiari malformation. The variable presentation of congenital scoliosis in a genetically unique population serves as testament to the complexity associated with its development, likely involving both environmental factors and a genetic predisposition.