Congenital scoliosis: a frontal plane evaluation of 251 operated patients 14 years old or older at follow-up.

INTRODUCTION

Congenital scoliosis, carrying an incidence between 0.5 and 1 per 1000 births, raise the problem of their evolutive potential.

HYPOTHESIS

Some predictive factors for the evolution of scoliotic curvature due to congenital vertebral malformation (CVM) can be found.

MATERIAL AND METHODS

This was a retrospective multicenter study of 251 patients, at least 14 years old when evaluated at end of follow-up, with CVM and spinal deformity predominating in the frontal plane.

RESULTS

38.8% of patients showed associated neurologic, visceral or orthopedic abnormalities. CVM was single in 60.6%, double in 20.3%, triple in 6.4% and multiple in 12.7% of cases. 34.1% of CVMs were thoracic. Congenital scoliosis curvature was single in 88.8% of patients, double in 10% and triple in 1.2%. Mean curvature angle was 31.7° at diagnosis (range, 0-105°) and 41.3° preoperatively (range, 10-105°). Sixty-one patients showed associated kyphosis. Mean change in postoperative curvature angle over follow-up was 1.6° (range, -20° to 38°) in the 73 patients managed by arthrodesis, -0.4° (-24° to 30°) in the 64 managed by epiphysiodesis, and 0.4° (-18° to 35°) in the 49 managed by hemivertebral (HV) resection. Results were found to correlate significantly with age at surgery for patients managed by epiphysiodesis, but not for those managed by HV resection or arthrodesis.

DISCUSSION

More than 30% of congenital scolioses involve associated intraspinal abnormality. All CVM patients should therefore undergo medullary and spinal MRI to assess the CVM in all three planes, and the medullary canal and its content. The evolution of scoliotic curvature induced by CVM is hard to predict. Several factors are to be taken into account: CVM type, number and location, and patient age. Curvature progression may be slow or very fast. It accelerates during the peak of puberty, stabilizing with bone maturity. Surgery is mandatory in evolutive scoliosis. Four procedures may be recommended, according to type of CVM and especially to patient age: arthrodesis, convex epiphysiodesis, HV resection or rib distraction. Surgery seeks to correct the spinal deformity induced by the CVM and prevent compensatory curvature and neurologic complications, while conserving sagittal and frontal spinal balance and sparing as many levels as possible. In case of HV involvement, the procedure of choice is CVM resection, which provides 87.5% good results in this indication; the procedure is relatively safe, conservative of spinal levels, and without age limit.

LEVEL OF EVIDENCE

Level IV. Retrospective study.