Intraoperative O-arm navigation yields 100% accuracy in pedicle screw placement for adolescent idiopathic scoliosis: a single-institution study.

BACKGROUND

Adolescent idiopathic scoliosis (AIS) often presents with significant spinal curvature and small, anatomically distorted pedicles, particularly in the thoracic spine. These factors make pedicle screw placement technically challenging and elevate the risk of neurovascular injury and poor bone purchase. Intraoperative O-arm navigation has emerged as a promising tool for enhancing screw placement accuracy and minimizing complications. This study aimed to (I) determine the accuracy of pedicle screws placed with intraoperative O-arm guidance at the thoracic and lumbar levels in spinal fusions for AIS; (II) evaluate postoperative curve correction and fusion maintenance; and (III) assess reoperation and complication rates due to screw misplacement.

METHODS

A single-institution retrospective review was performed for pediatric patients (<18 years) who underwent posterior spinal instrumentation and fusion (PSIF) for AIS from June 2023 to August 2024. Patients included had Lenke 1AN-6C curves and preoperative Cobb angles >40°. Intraoperative O-arm CT was used for navigation and final assessment of screw positioning. Postoperative X-rays assessed correction and alignment. Chart review identified reoperations and complications attributable to screw malposition.

RESULTS

A total of 227 pedicle screws were placed in 12 AIS patients (mean age: 14 years). All screws (100%) were accurately placed without cortical breach. The Wilcoxon Signed-Rank test showed a large, significant difference between the Pre-Operative Cobb Angles (Mdn =51.5, n=12) and the Post-Operative Cobb Angles (Mdn =19.7, n=12), (W+ =0, P<0.001, r=-1). 0 patients experienced screw-related complications or required reoperation.

CONCLUSIONS

In AIS patients with severe curves and narrow pedicles, intraoperative O-arm navigation provides precise, breach-free pedicle screw placement and facilitates safe, durable deformity correction. These results support the use of intraoperative navigation in complex pediatric spinal deformity surgery.