Objective: To compare the effect of thoracoscopic anterior release combined with posterior spinal fusion and posterior-only approach with an all-pedicle screw construct in the treatment of rigid thoracic adolescent idiopathic scoliosis. Methods: From June 2001 to June 2010, 63 patients who were admitted to our hospital with thoracic Cobb angle ≥80 degrees and the flexibility ≤40% were enrolled in our study. They were treated with either a combined anterior/posterior spinal fusion with hooks and screws (group A, n=25) or a posterior spinal fusion alone with an all-pedicle screw construct (group B, n=38). The thoracic Cobb angle in the standing whole-spine anteroposterior x-ray, thoracic kyphosis (T5–T12) Cobb angle, imaging examination parameters, fixation segments, implant density, and complications between the 2 groups were compared. Results: There were no significant differences in operation time, bleeding volume, length of hospital stay, preoperative coronal, sagittal Cobb, coronal curve flexibility, or postoperative coronal Cobb correction ratio between the 2 groups. Moreover, no significant difference in the Scoliosis Research Society-22 score at the last follow-up was present in the 2 groups, although it had been improved compared with that presented during the preoperative period. The implant density of group A (44±4%) was significantly lower than that of group B (55±5%) (P<0.001). In group A, the main complication was chylothorax (n=2) and hemopneumothorax (n=2). In group B, acute intestinal obstruction was observed in 2 patients and pleural effusion was observed in 1 patient. In addition, 12 screws were misplaced (12/403, 3.0%) in group B. Conclusions: In patients with rigid thoracic adolescent idiopathic scoliosis, posterior-only approach with an all-pedicle screw construct could achieve the same curve correction as a combined anterior/posterior spinal fusion by increasing the implant density. However, for scoliosis patients with a high risk of implant complications, anterior release combined with posterior spinal fusion is still recommended.