The risk of spinal deformity after selective dorsal rhizotomy.

To define the risk of spinal deformity after selective dorsal rhizotomy (SDR) for the treatment of spasticity due to cerebral palsy, 43 patients were reviewed before and after the procedure. The average length of follow-up was 5.3 years with a range of 2-9 years. Scoliosis was present in three patients before rhizotomy. One patient had a thoracic hyperkyphosis, and another, a lumbar hyperlordosis deformity preoperatively. Wide laminectomies were performed in 46 patients, and none had laminoplasties. Twenty-eight significant spinal deformities developed in 19 patients; 15 cases of scoliosis, seven instances of lumbar hyperlordosis, five thoracic hyperkyphosis, and one L4-5 spondylolisthesis. Five patients were placed in braces, and three patients went on to have surgical stabilization of their deformities. For the entire group, the risk of developing a structural spinal deformity was 36%, with 6% requiring stabilization at an average of 4.9 years after SDR. Older age, more severe neurologic impairment, and preexisting spinal deformity seems to increase this risk.