Spinal deformities following selective dorsal rhizotomy

Object. Selective dorsal rhizotomy (SDR) has been shown to provide considerable benefit to children with spastic cerebral palsy (CP). The authors sought to evaluate the risks of postoperative spinal deformities in patients following SDR. Methods. All patients who underwent SDR at McGill University between 1991 and 2001 were identified. Hospital charts and radiographic spinal studies (both preoperative and the latest postoperative) were systematically reviewed. Univariate and multivariate regression analyses were conducted to test all independent variables of potential interest to determine risk factors more likely to be associated with spinal deformity. There were 98 patients whose mean age at surgery was 5.1 years; the mean radiographic follow-up duration was 5.8 years. Thirty-nine (44.8%) of 87 patients in whom postoperative weight-bearing radiographs were obtained had mild scoliosis, and 17 in whom standing radiographs were acquired had hyperlordosis. In all, 18 of 94 patients (19.1 %) who had postoperative radiographs on which the lumbosacral junction was visible were found to have spondylolisthesis. Regression analysis identified the severity of preoperative CP as an important predictor, and less ambulatory patients were more likely to have scoliotic curves. Younger age at surgery and male sex were factors associated with a lower rate of hyperlordosis. Spondylolisthesis developed only in ambulatory children. None of the patients experienced clinically significant deficits. Conclusions. There was a high rate of radiologically documented deformities in patients with CP who underwent SDR. Ambulatory function, CP severity, age at surgery, and sex may be contributing factors.