Type 3 bone-disc-bone osteotomy (grade 4+ osteotomy) combined with presurgical halo-pelvic traction: a safe and effective solution to correct severe angular-like kyphoscoliosis.

Background: Treatment of severe angular-like kyphoscoliosis is a technically demanding surgical challenge and requires high-risk spinal osteotomy, such as vertebral column resection. Preoperative halo-pelvic traction is commonly used to decrease the curve magnitude. However, few studies have utilized the potent method of bone-disc-bone osteotomy, which could theoretically provide correction up to 60°. This study aimed to evaluate the safety and effectiveness of type 3 bone-disc-bone osteotomy combined with presurgical halo-pelvic traction to correct severe angular-like kyphoscoliosis. Methods: This was a retrospective cohort study. Patients with severe angular-like kyphoscoliosis who underwent presurgical halo-pelvic traction and type 3 bone-disc-bone osteotomy from January 2017 to December 2019 were consecutively reviewed. Patient demographics and clinical data were recorded. The coronal and sagittal Cobb angles were measured preoperation, post-traction, post-operation, and at the final follow-up. Complications were also recorded. Patients' health-related quality of life was evaluated by the Scoliosis Research Society 22 (SRS-22) questionnaire. Paired Student's t test and one-way analysis of variance were used for comparisons among different groups. Results: Thirty patients (18 females and 12 males) with an average age of 20.2 years (range, 13-33 years) were included. The mean preoperative coronal and sagittal Cobb angles were 123.1°±16.4° (range, 90°-155°) and 120.3°±19.9° (range, 90°-156°), respectively. After 2.9±0.7 months (range, 2-4 months) of halo-pelvic traction, the coronal and sagittal Cobb angles decreased significantly to 81.9°±13.2° and 76.0°±12.6°, respectively. Postoperatively, the scoliotic and kyphotic angles further decreased to 42.4°±12.2° and 33.9°±8.8°, respectively. After a mean follow-up of 2.93±1.05 years, the correction rates were maintained at 64.3%±10.6% and 70.5%±6.3%, respectively. Nine patients experienced positive evoked potential events during surgery. Common complications after surgery included transient lower extremity weakness, pneumonia, and pleural effusion. The self-image scores were significantly improved from 2.66±0.27 to 3.36±0.23 compared to preoperation. Conclusions: This study proposes a novel strategy to correct severe angular-like spinal deformities. The combination of presurgical halo-pelvic traction and type 3 bone-disc-bone osteotomy (grade 4+ osteotomy) achieves substantial correction and satisfactory aesthetic outcomes without serious complications.