Anterior spinal fusion versus posterior spinal fusion for moderate Lumbar/Thoracolumbar adolescent idiopathic scoliosis

Study Design. A prospective study. Objective. Comparison study of radiologic and clinical outcomes, efficiency, and cost between anterior spinal fusion (ASF) and posterior spine fusion (PSF) in surgical treatment of moderate lumbar/thoracolumbar adolescent idiopathic scoliosis (AIS). Summary of Background Data. ASF and PSF indicated for lumbar and thoracolumbar adolescent idiopathic scoliosis surgical treatment have respective advantages and disadvantages. However, up until today, a related prospective AIS comparative study has rarely been reported. Methods. Thirty-two cases in this prospective study with patients enrolled in either method A or B alternately in a sequence were divided into 2 groups. Group A underwent ASF with single solid rod and single screw constructs, and group B underwent PSF with segmental total pedicle screw system. Inclusion criteria were: (1) AIS diagnosis; (2) diagnosis classification as Lenke5CN type; (3) Cobb angles 35 60 on anteroposterior view radiographs. Exclusion criteria were: (1) a history of spinal surgery; (2) age younger than 10 years; (3) Risser sign 0 degrees; (4) lumbar/thoracolumbar kyphosis. All patients were observed with 2-year minimum follow-up (24-46 months). Clinical and radiologic outcomes of both groups A and B were analyzed. Results. Statistical t test or Mann-Whitney U test demonstrated no significant difference in preoperative age (P = 0.380), Risser sign (P = 0.733), magnitude (P = 0.936), flexibility (P = 0.815), apical vertebra rotation (AVR, P = 0.756), and apical vertebra translation (AVT, P = 0.355) of the lumbar/thoracolumbar curves, trunk shift (TS, P = 0.448), sagittal kyphosis from T5-T12 (P = 0.792) and sagittal lordosis from L1-L5 (P = 0.299). Average coronal correction of thoracolumbar/lumbar curves was 83% after surgery and 77% at follow-up in group A and 87% after surgery and 82% at follow- up in group B (P = 0.236 and P = 0.138). No significant differences were observed regarding correction of sagittal alignment, TS, AVT, AVR and hospitalization days on last follow-up between both groups (P = 0.05). No pseudarthrosis, reoperation, neurologic complications, infection, and no other problems were observed. Excellent clinical fusion results were present in all patients on their last follow-up. However, significant differences were evident in group A in regards to reduced operative time (P = 0.046), reduced estimated blood loss (P = 0.003), decreased blood transfusion (P = 0.006), reduced implants cost and hospitalization expenses (P = 0.000). Additionally, group A had shorter fusion levels than group B (p(50) = 4 vs. p(50) = 5, P = 0.003). Conclusion. ASF versus PSF comparison in treating moderate lumbar/thoracolumbar AIS did not show significant differences in regards to safety or efficacy but demonstrated shorter fusion levels, reduced surgical trauma and costs in ASF.