Background: There is no consensus on the correction of adolescent idiopathic scoliosis (AIS) double major curves. Posterior only fusion may require extensive distal fusion or additional instrumentation, subsequently leading to a variety of complications. Alternatively, an anterior-posterior fusion (APF) is a powerful technique which can save lumbar motion segments while restoring lumbar apical rotation and tilt effectively.
Methods: A retrospective review was performed at our institution (RNOH) for patients undergoing AIS correction. Two thousand three hundred and fourteen cases from 2006 to 2012 (minimum 2-year follow-up) were identified. Preoperative demographics and mean values of: Standing radiograph Cobb, Harrington Stable Zone, Supine Bending Radiograph Cobb and Postoperative mean values: Correction Rate, Supine Bend Flexibility and Supine Bending Flexibility Index, LIV Tilt and Rotation Perdriolle Grade.
Results: Fifty-eight of 2,314 consecutive AIS cases were managed with a two stage anterior-posterior strategy. Comparison of pre- and post-operative radiographic parameters proved significant for cobb angle (MT: 62.7, 19.5; TL: 59.1,12.6; P<0.001), thoracic kyphosis (26.36°, 8.59°; P<0.001), lumbar lordosis (59.57°, 50.66°; P<0.001), LIV-ground angle (21.9°, 4.5°; P<0.001), and reduction in Perdriolle grade (1.7, 1.1; P<0.001). On average, the two-stage APF approach saved 1.58 motion segments compared to the HSZ method.
Conclusions: This technique achieved a high postoperative correction rate and supine bend correction index despite differing levels of stiffness, and an LIV of L3 or above was achieved in 90% of cases. The two stage APF surgical strategy attains desirable correction of coronal, sagittal, and rotational alignment in addition to saving lumbar motion segments compared to other methods.
