Lumbar Spine Instability Fracture in a Patient With Residual Adolescent Idiopathic Scoliosis: A Case Report.

Lumbar spine instability fractures in patients with residual adolescent idiopathic scoliosis (AIS) are rare, and optimal treatment strategies remain unclear. Surgical management must consider both immediate fracture stabilization and the potential need for future scoliosis correction. A 24-year-old woman with residual AIS (Cobb angles: 47° thoracic, 60° lumbar) sustained an AO Spine Classification Type B2 lumbar fracture (L2) after falling from the second floor. She presented with severe back pain but no neurological deficits. Radiographic evaluation confirmed vertebral body collapse and posterior ligamentous injury. Posterior fixation alone was chosen over combined anterior-posterior fixation to maintain future options for scoliosis correction. The patient recovered uneventfully, achieving solid bone fusion by seven months postoperatively, at which time the implants were also removed. At the two-year follow-up, she remained asymptomatic with no progression of scoliosis or instability. For lumbar fractures in patients with residual AIS, surgical decision-making should consider future scoliosis management. Posterior fixation alone may be a viable strategy to ensure both stability and surgical flexibility.