Analysis of the sagittal plane after surgical management for Scheuermann's disease - A view on overcorrection and the use of an anterior release

Study Design. A historic cohort study was conducted to investigate surgical correction and sagittal alignment in 33 patients with thoracic Scheuermann's disease. Objective. To evaluate kyphosis correction, correction loss, sagittal balance, and the effect of an anterior release. Summary of Background Data. Currently, both posterior and anteroposterior techniques seem to produce impressive corrections for Scheuermann's disease. However, few reports have been made on sagittal malalignment after surgery. Methods. A cohort of 33 patients who had undergone surgery for their Scheuermann's kyphosis were reviewed: Group A: posterior technique (n = 16), Group B: anteroposterior technique (n = 17). Pre- and postoperative curve morphometry (Cobb, Ferguson, Voutsinas), balance (C7 plumb line), and Oswestry score were compared. Results. The mean follow-up period was 4.5 +/- 2 years (range, 2-8.2 years), The mean preoperative kyphosis (Cobb) was 78.7degrees +/- 8.9degrees, and the mean postoperative kyphosis was 51.7degrees +/- 10.3degrees. At follow-up evaluation, the correction loss was 1,4degrees +/- 3.9degrees. There was no difference 'in curve morphometry, correction, sagittal balance, average age, and follow-up period between Groups A and B. One junctional kyphosis, in Group B, was noted. After surgery, all the patients were satisfied, and the Oswestry score showed significant improvement. No neurologic complications were observed. Conclusions. Good follow-up results included a 100% follow-up rate, adequate corrections, little correction loss, lower Oswestry scores, and a high satisfaction rate in both groups. The anteroposterior treatment did not influence the curve morphometry more than posterior fusion only. In reducing postoperative sagittal malalignment, the authors believe that surgical management should aim at a correction within the high normal kyphosis range of 40degrees to 50degrees, consequently providing good results and, particularly in flexible adolescents and young adults, minimizing the necessity for an anterior release.