Spinal wedge osteotomy by a single posterior approach for correction of severe and rigid kyphosis or kyphoscoliosis

Study Design. Seven patients with severe angular kyphotic deformity of the spine were treated by circumferential spinal wedge osteotomy using a single posterior approach. Objective. To evaluate the surgical outcomes for seven patients with severe angular kyphosis or kyphoscoliosis treated by spinal wedge osteotomy. Summary of Background Data. Excellent surgical outcomes have been reported-for procedures such as hemi-vertebra excision, vertebral body resection, and spinal osteotomy for angular kyphosis or kyphoscoliosis. However, the safety and efficacy of these procedures for severe and rigid deformities have not been established. Methods. The surgical procedure involves circumferential exposure of the apex vertebra to the anterior aspect using a single posterior approach. Sparing only the spinal cord, the surgeon performs' circumferential wedge bone resection, closure; correction, and stabilization by instrumentation while monitoring the spinal cord. Seven patients (3 kyphotics and 4 kyphoscoliotics) treated by this procedure were evaluated for a minimum of 2 years. Underlying conditions comprised five cases of congenital deformity with hemivertebrae and two cases of skeletal dysplasias: The mean age at surgery was 16.5 years, and the mean follow-up period was 6.9 years. Results. Before surgery; the mean kyphotic curve was 105.4degrees (range, 68-150degrees), and the mean scoliotic curve was 85.3degrees (range, 60-132degrees). After surgery, the curves averaged 48.9degrees and 40degrees, respectively; yielding corrections of 52.9% and 54.9%. The mean posterior trunk shift in global sagittal balance was 21 mm before surgery, becoming 3 mm after surgery. Progressive spinal cord dysfunction had developed in three patients before surgery. In all three, postoperative neurologic improvement was observed. Postoperative complications consisted of transient, unilateral leg paresis in two patients. No incidents of infection or pseudarthrosis were observed. Conclusions: Spinal wedge osteotomy by the single posterior approach is a reliable and safe surgical technique for correcting severe rigid angular kyphosis or kyphoscoliosis.