Combined anterior and posterior instrumentation in severe and rigid idiopathic scoliosis.

A prospective clinical and radiographic evaluation of 33 consecutive patients with severe and rigid idiopathic scoliosis (average Cobb angle 93 degrees, flexibility on bending films 23%) were treated with combined anterior and posterior instrumentation with a minimum follow-up of 2 years. All patients underwent anterior release and VDS-Zielke Instrumentation of the primary curve. In highly rigid scoliosis, this was preceded by a posterior release. Finally, posterior correction and fusion with a multiple hook and pedicle screw construct was performed. Thirty patients were operated in one stage, three patients in two stages. Preoperative curves ranged from 80 to 122 degrees Cobb angle. Frontal plane correction of the primary curve averaged 67% with an average loss of correction of 2 degrees . The apical vertebral rotation of the primary curve was corrected by 49%. In all but three patients, sagittal alignment was restored. There were no neurological complications, deep wound infections or pseudarthrosis. Combined anterior and posterior instrumentation is safe and enables an effective three-dimensional curve correction in severe and rigid idiopathic scoliosis.