Coronal Decompensation After Posterior-only Thoracolumbar Hemivertebra Resection and Short Fusion in Young Children With Congenital Scoliosis

Study Design. A retrospective study. Objective. To determine the incidence and risk factors of coronal decompensation after posterior-only thoracolumbar hemivertebra (HV) resection and short fusion in patients younger than 5-years old. Summary of Background Data. Postoperative coronal decompensation may occur in operated patients during the follow up. However, there is a paucity of valid data regarding this complication in very young patients with thoracolumbar HV. Methods. This study reviewed a consecutive series of patients (younger than 5 years) who had undergone posterior-only hemivertebrectomy and short fusion from January 2006 to December 2014. They had a minimum follow-up of 24 months. According to the coronal compensation behavior, they were divided into two groups: Group P (progressed, curve decompensated beyond twenty degrees) and Group NP (nonprogressed, curve well compensated). Results. There were 179 patients included in this study. Mean age at surgery was 38 ± 11 months. Mean follow-up was 41 ± 11 months. Postoperative coronal decompensation was identified in 18 patients (rate, 10.1%) who constituted Group P. The remaining 161 patients had a well-compensated pattern. In contrast to Group NP, the patients in Group P had greater preoperative lowest instrumented vertebra (LIV) translation (18.5 mm ± 6.4 mm vs. 10.5 mm ± 4.9 mm, P < 0.01), and higher postoperative LIV disc angle (7.0° ± 3.1° vs . 3.1° ± 3.3°, P < 0.01) after surgery. During the follow up, LIV translation and LIV disc experienced continuous aggravation until initiation of bracing. Preoperative LIV translation (≥15.1 mm) and postoperative LIV disc angle (≥5.5°) were identified as two independent risk factors of coronal decompensation after surgery. Conclusion. After thoracolumbar hemivertebrectomy in children younger than 5 years, the overall rate of coronal decompensation is approximately 10.1%. As two independent risk factors of postoperative coronal decompensation, preoperative LIV translation (≥15.1 mm) and postoperative LIV disc angle (≥5.5°) should on all accounts be the major causes for concern. Level of Evidence: 4