Correction of thoracic kyphosis and lumbar lordosis in the treatment of idiopathic scoliosis treatment with Cotrel-Dubousset instrumentation.

Background. The treatment of thoracic kyphosis and lumbar lordosis with the C-D method remains controversial. Material and methods. The lateral radiographs of 70 patients with King I, II, III, IV idiopathic scoliosis, treated with C-D instrumentation, were retrospectively analyzed. The average age was 14 +/- 1.8 years. Thoracic kyphosis between T2 and T12 and lumbar lordosis between L1 and L5 were measured. Results. Normalization of thoracic kyphosis occurred in 15 of the 22 hypokyphosis patients. The largest kyphosis correction (average +12 +/- 8 degrees ) was in the preoperative hypokyphosis group. A deep hyperkyphosis (average 64 degrees ) was found preoperatively in patients with postoperative hyperkyphosis. Kyphosis correction in the instrumented region was often reverse to the uninstrumented region correction. Lumbar lordosis remained normal in 29 (63%) and hypolordosis occurred in 14 (31%) of the 45 patients with normal preoperative lordosis. When instrumentation below L1 was performed, a greater decrease in lumbar lordosis was observed. Conclusions. The C-D method enables good kyphosis and lordosis correction in scoliotic patients, but problems may occur in greater deformities. Longer lumbar instrumentation may result in decreased lumbar lordosis.