Romosozumab Following Long-Term Bisphosphonate Use for Severe Osteoporotic Vertebral Collapse (Vertebra Plana): Potential Facilitation of Vertebral Fracture Healing

Purpose: To evaluate the clinical and radiologic effects of switching from long-term bisphosphonate therapy to romosozumab in an elderly patient with severe osteoporosis and vertebra plana–type severe osteoporotic vertebral collapse, followed by transition to denosumab maintenance therapy.Methods: An 85-year-old woman with a history of osteoporotic fractures and prolonged intravenous bisphosphonate therapy presented with an acute L2 compression fracture. Conservative management with a body cast was initiated, and romosozumab was introduced as a switching therapy when anabolic treatment was indicated. Thoracolumbar spine radiographs were obtained at presentation and at 1, 3, 7, and 12 months after injury. Computed tomography was performed at presentation and again at 7 and 12 months to assess fracture consolidation. Bone mineral density (BMD) was measured beginning at 18 months after injury and annually thereafter. Functional assessments were recorded throughout a 30-month follow-up period.Results: During romosozumab therapy, the L2 vertebra plana–type severe osteoporotic vertebral collapse showed marked radiologic improvement, characterized by progressive intravertebral bone fill-in and gradual restoration of trabecular continuity without further loss of height. Serial follow-up CT and MRI demonstrated consolidation of the previously cavitated vertebral body, indicating substantial structural recovery rather than simple stabilization. Clinically, the patient experienced steady improvement in pain and ambulatory capacity. After completing six monthly doses of romosozumab, therapy was transitioned to denosumab. L2 bone mineral density improved from a T-score of –1.7 to –0.9, accompanied by gains in femoral BMD. No additional fragility fractures occurred throughout the follow-up period.Conclusions: Switching from long-term bisphosphonate therapy to romosozumab resulted in improved BMD, progressive vertebral bone fill-in, and stabilization without further collapse in this elderly patient with severe osteoporosis. Although not established as a fracture-healing agent, romosozumab may serve as a practical anabolic option in selected cases, with denosumab maintenance ensuring ongoing skeletal protection.