To observe the effect of selective dorsal rhizotomy (SDR) on the deformity of the lumbar spine, a retrospective review was conducted from October 1992 to December 2002 on children who had undergone SDR in our department, and in whom preoperative and postoperative spine radiographs had been obtained. The angles of hyperlordolysis were measured. The study group comprised 219 patients, in which 61 cases were followed up and examined between May 2004 and February 2005. The mean age at surgery was 6.9 years (range 3-20 years), with a mean time to recent follow-up radiographs of 6.3 years (5-9 years). A total 219 children underwent laminectomy from L(2)-S(1). Scoliosis existed in one case, and two cases of L(5) spondylolysis were detected before surgery. One case presented lumbar hyperlordosis. After SDR, 10 cases showed distinctively abnormal walking posture of hyperlordolysis. Compared with the preoperative angle of hyperlordolysis, the angle was improved after the operation. Among them, four patients developed spondylolysis and spondylolisthesis (grade I). We also observed that one case developed lumbar kyphosis deformity. In conclusion, cerebral palsy patients may develop spinal deformity. Some cases showed distinctively abnormal walking posture of hyperlordolysis, and they developed spondylolysis and spondylolisthesis after surgery.