Cotrel-Dubousset instrumentation in idiopathic scoliosis a 5-year follow-up.

The results of Cotrel-Dubousset instrumentation in 50 patients with idiopathic scoliosis were evaluated. The patients were followed for 24 to 108 months with a mean follow-up of 5 years. Their average age was 15 years and 3 months. The scoliotic curves were classified according to King et al. There were 4 type I, 20 type II, 10 type III, 10 type IV and 1 type V. Five curves could not be included in this classification: 2 double lumbar, 1 right lumbar and 2 left thoracic curves. Coronal plane analysis showed an average postoperative correction of 56% for thoracic curves and 57% for lumbar curves. The loss of correction at the most recent follow-up was 14% and 15%, respectively. Higher corrections were obtained in King types III and IV than in types I and II. Mild increase of thoracic kyphosis was noted in previously hypokyphotic curves. The normal sagittal curve in the lumbar spine was maintained at the most recent follow-up. There were no major neurological deficits. A symptomatic pseudarthrosis developed in one patient with a concomitant L5-S1 spondylolisthesis. Another patient developed a delayed deep wound infection that resolved after the instrumentation was removed. The data from this study suggest that Cotrel-Dubousset instrumentation achieves a satisfactory correction of the curves with an acceptable loss of correction over time. The system also preserves lumbar lordosis when fusion to the lower lumbar spine is required.