Impact of Preoperative Halo Traction on Cobb Angle Reduction in Adolescent Idiopathic Scoliosis: A Retrospective Analysis

Background/Objectives: Adolescent idiopathic scoliosis (AIS) is a three-dimensional spinal deformity often requiring surgical correction in severe cases. Halo-gravity traction (HGT) is commonly employed preoperatively to enhance spinal flexibility and reduce curve severity. This study aimed to evaluate the effectiveness of HGT in reducing Cobb angles in AIS and to assess how patient age, skeletal maturity (Risser score), and curve type (Lenke classification) influence treatment response. Methods: We conducted a retrospective cohort study of 28 AIS patients with Cobb angles > 65° who underwent preoperative HGT followed by posterior spinal fusion. Traction was applied for a mean of 24.64 days, reaching 40–50% of each patient’s body weight. Radiographic measurements were collected pre-traction, post-traction, and postoperatively. Statistical analyses included paired t-tests, Pearson correlations, Kruskal–Wallis tests, and linear regression. Results: Mean primary Cobb angle was reduced from 82.46° pre-traction to 61.00° post-traction (26.09% reduction) and further to 29.54° postoperatively (64.58% total reduction). Similar reductions were observed in secondary curves. No statistically significant correlations were found between age or Risser score and the magnitude of correction. Lenke type 3 showed the highest traction response, while type 5 had the greatest surgical gain. Curve type and skeletal maturity did not significantly affect final outcomes. Conclusions: Halo-gravity traction is a safe and effective adjunct in the surgical treatment of severe AIS, achieving substantial Cobb angle reduction. The degree of correction was not significantly influenced by age, Risser score, or curve type, supporting the broad applicability of HGT across adolescent patients.