Selective thoracic fusion with segmental pedicle screw fixation in the treatment of thoracic idiopathic scoliosis - More than 5-year follow-up

Study Design. Retrospective study. Objectives. To evaluate outcomes of selective thoracic fusion with segmental pedicle screw fixation in thoracic idiopathic scoliosis with a minimum 5-year follow-up. Summary of Background Data. Segmental pedicle screw fixation has been proven to enable true segmental control and greater correction both in coronal and sagittal planes of scoliosis. However, there is no long-term study of selective thoracic fusion with segmental pedicle screw fixation in thoracic idiopathic scoliosis. Methods. Two hundred and three thoracic idiopathic scoliosis patients with 236 thoracic curves subject to selective thoracic fusion with segmental pedicle screw fixation were analyzed. Mean patient age at the time of operation was 13.8 years ( range: 8.9-18). Results. The preoperative thoracic curve of 51 +/- 12 degrees was corrected to 16 +/- 7 degrees (69% correction, 3% loss of correction) at the most recent follow-up. The noninstrumented lumbar curve of 30 +/- 10 degrees was corrected to 10 +/- 8 degrees (66% correction, 5% loss of correction) at the most recent follow-up. The preoperative thoracic kyphosis of 18 +/- 11 degrees and the lumbar lordosis of 43 +/- 10 degrees were improved to 23 +/- 8 degrees and 46 +/- 9 degrees, respectively, at the most recent follow-up. There was no junctional kyphosis at the most recent follow- up. Coronal decompensation at the most recent follow- up occurred in 10 patients. Postoperative adding-on occurred in 17 patients, who were fused two levels short of the neutral vertebra. Of the 2,867 thoracic pedicle screws inserted in the thoracic level, 43 screws were found to be malpositioned ( 1.5%), but they did not cause neurologic complications or adversely affect the long-term results. Conclusions. Selective thoracic fusion with segmental pedicle screw fixation in thoracic idiopathic scoliosis had satisfactory radiographic and clinical outcomes after surgery and has been well-maintained for minimum 5-year follow- up. It is a safe and effective method for preservation of lumbar motion segments as well as for restoration and maintenance of both coronal and sagittal alignment.