Long-term Results After the One-stage Posterior-only Surgical Correction of Thoraco-lumbar Kyphoscoliosis in Congenital Spine Deformity Caused by Two Ipsilateral Hemi-vertebrae

Abstract

Background: Two ipsilateral hemivertebrae is less common and presents severe growth imbalance produced by the vertebral anomalies. However, there is a paucity of reports regarding this double ipsilateral thoracolumber hemivertebrae. The purpose was to evaluate the long-term outcomes of the one-stage posterior-only surgical correction of thoraco-lumbar kyphoscoliosis caused by two ipsilateral hemi-vertebrae. Methods: From 2006 to 2014, a total of 14 consecutive pediatric patients with congenital thoraco-lumbar kyphoscoliosis due to two ipsilateral hemivertebrae were treated by posterior excision of hemivertebrae with short segment fusion. The following parameters were measured: coronal segmental curve, cranial and caudal compensatory curve, segmental kyphosis, lumbar lodorsis, trunk shift, apical vertebra translation and sagittal vertical axis. These results were compared and evaluated in preoperative, immediately postoperative and at the final follow-up. All patients had a minimum of 5 years of follow-up period.Results: The mean age at surgery was 11.1±4.8 years (2yos to 17yos). The mean follow-up period was 80.2±19.4 months (60mons to 117mons). There was a mean improvement of 74.2% in the segmental curve from a mean angle of 64.1° before surgery to 15.8° at the latest follow-up. The cranial and caudal curve improved of 69.8% and 69.0% from 25.6° to 7.7°, 26.9 to 8.2, respectively. The mean thoracolumbar kyphosis was 59.9° before and 13.6° after surgery, 20.8° at the final follow-up. Alignment in the coronal and sagittal plane was either maintained or improved within normal values in all patients.Conclusions: Good correction and spinal balance can be achieved by posterior-only hemivertebrectomy in patients with thoracolumbar kyphocsoliosis caused by two ipsilateral hemivertebra. The complication of neurological injury is low but a technically demanding procedure. More attention should be paid in residual curve progression after surgery.