Closing-opening wedge osteotomy to correct angular kyphotic deformity by a single posterior approach.

Abstract

Seven patients with angular kyphotic deformity of the thoracic or thoracolumbar spine were treated by closing-opening wedge osteotomy using a single posterior approach. To examine the safety and efficacy of closing-opening wedge osteotomy for angular kyphosis. Correction osteotomy of severe kyphosis is a challenging operation. A two-stage operation has been commonly used: anterior release and decompression followed by posterior correction and fusion. Seven patients with angular kyphosis were treated. The apex level of kyphosis was T5 in one patient, T11 in one, and T12 in five. There was old fracture in five patients, congenital deformity in one, and neurofibromatosis in one. The first 30-35 degrees of kyphosis are corrected using the closing wedge technique with the hinge of the anterior longitudinal ligament after veretebrectomy and circumspinal decompression of the spinal cord. Then the hinge is moved posteriorly to the spinal cord and the remainder of the requisit angle of osteotomy is corrected using the opening-wedge technique (closing-opening wedge osteotomy). Spinal curvature is stabilized using posterior instrumentation and graft. Localized kyphosis was reduced from an average of 67 degrees to 18 degrees at 2.2 to 7.5 years' follow-up. Sagittal alignment from T1 to the sacrum became more physiologic than before. There were no neurologic complications. Bony fusion was achieved in all patients, and there was no correction loss. Satisfactory correction is safely performed by closing-opening wedge osteotomy with a direct visualization of the circumferentially decompressed spinal cord. Although the performance is technically laborious, it offers good correction without jeopardizing the integrity of the spinal cord.