Severe rigid scoliosis: Evaluating the role of anterior release and its impact on pulmonary function

Severe rigid scoliosis (>90° Cobb angle; <30 % flexibility) presents major challenges in deformity correction and pulmonary preservation. This narrative review outlines current surgical strategies, with a focus on anterior spinal release and its biomechanical and respiratory implications. Disc-rib-head excision improves axial rotation and sagittal alignment, reducing the need for extensive posterior osteotomies and high implant density. Techniques such as open thoracotomy, video-assisted thoracoscopic surgery (VATS), mini-open thoracoscopically assisted thoracotomy (MOTA), and posterior convex release with interbody fusion (PCRIF) yield comparable coronal and sagittal corrections. Minimally invasive approaches are associated with reduced blood loss, postoperative pain, and hospital stay. Pulmonary function typically declines by ∼40 % postoperatively due to inflammatory lung injury, but returns to baseline or improves within 6-12 months. Preoperative halo-gravity or femoral traction enhances curve flexibility, thoracic volume, and may improve respiratory parameters. For long, rounded curves, especially with coronal and sagittal imbalance, a staged approach-anterior release via thoracotomy followed by posterior instrumentation after 10-14 days-is preferred. Ponte osteotomies and asymmetric pedicle subtraction osteotomy (PSO) may be added for Cobb angles >120° or significant hyperkyphosis. In contrast, sharply angulated or focal curves, typical of congenital, neurofibromatosis-related, or post-infective scoliosis, respond better to posterior vertebral column resection (PVCR). Anterior instrumentation is especially useful in thoracolumbar curves to preserve motion segments and prevent crankshaft phenomenon in growing children. Despite transient pulmonary decline, long-term respiratory outcomes are favourable. A morphology-driven, patient-specific surgical strategy is essential to maximize correction, preserve function, and minimize complications in managing severe rigid scoliosis.