BackgroundTo investigate the effectiveness and feasibility of a novel vertebral osteotomy technique, transpedicular opening-wedge osteotomy (TOWO) for correcting rigid thoracolumbar kyphotic deformity in patients with ankylosing spondylitis (AS).Methods18 AS patients underwent TOWO for correcting rigid thoracolumbar kyphosis. Radiographic parameters were compared before surgery, 1 week after surgery and at last follow-up. SRS-22 questionnaire was assessed before surgery and at last follow-up to evaluate clinical improvement. The operating time, estimated blood loss and complications were analyzed. ResultsThe mean operating time and estimated blood loss were 236 minutes and 595 ml, respectively. Sagittal parameters improved significantly after surgery. The height of anterior column of osteotomized vertebrae was increased significantly at 1 week after surgery and last follow-up when compared to preoperative, but the height of middle column did not changed significantly. SRS-22 scores were improved significantly at last follow-up than preoperative. Solid fusion was achieved in all patients after 12 months follow-up, no screw loosening, screw pull out or rod breakage was noticed at last follow-up. ConclusionsTOWO could achieve a satisfactory kyphosis correction by opening anterior column instead of vertebral body decancellation and posterior column closing, which simplified the osteotomy procedure and improved the surgical efficacy.