Long-Term Follow-Up of Anterior Spinal Fusion for Thoracolumbar/Lumbar Curves in Adolescent Idiopathic Scoliosis

Study Design. Retrospective patient series analysis with update of long-term data. Objective. To define the long-term prognosis of the thoracolumbar/lumbar correction after selective anterior spinal fusion (ASF) in adolescent idiopathic scoliosis (AIS). Summary of Background Data. The ASF is a well-described procedure for the treatment of AIS. The correction reliability over time, the consequences in adjacent spinal levels and patient's quality of life are fundamental for the characterization of AIS treatment. Methods. One hundred seven patients were submitted to single-rod ASF for thoracolumbar/lumbar (ThL/L) AIS between 1993 and 2016 in a single-surgeon experience. Seventy five were available for final follow-up evaluation 9 years +/- 4 (2-23) after surgery. A clinical and sequential radiographic evaluations were performed. Results. The mean age at surgery was 16 years +/- 2.33 (14-20) and 94 (87%) were females. The mean final follow-up of the 75 patients available was 9 years +/- 4 (2-23). Sixty-five patients had a Lenke type 5C curve and 10 had a type 6C curve. The mean values of the Scoliosis Research Society 22 (SRS-22) questionnaire in Lenke 5C was 92 +/- 9 (71-109) and in Lenke 6C 90.3 +/- 9 (75-107). In Lenke 5C group, the mean preoperative ThL Cobb angle was 38.4 degrees +/- 9.3 (21-60) and the postoperative was 5.9 degrees +/- 4.5 (0-18; P < 0.001) being similar at the final follow-up (P > 0.05). In Lenke 6C group, the mean preoperative ThL Cobb angle was 58.6 degrees +/- 13.9 (40-90) and the postoperative ThL Cobb was 22.6 degrees +/- 14.5 (5-48, P < 0.001) being similar at the final follow-up (P > 0.05). The mean preoperative Thoracic (Th) Cobb angle was 39 degrees +/- 7.6 (30-50), the postoperative was 30.6 degrees +/- 10.1 (14-49, P < 0.008) and in the final follow-up was 29.3 degrees +/- 10.7 (11-48, P < 0.011). Conclusion. ASF is a safe procedure in the treatment of ThL/L with good long-term results and high rates of satisfaction among patients with AIS Lenke type 5C. The partial correction was frequent in Lenke type 6C despite the absence of progression in the non-instrumented curves.