Surgical Management of Exceptionally Severe Cubitus Varus Deformity in Osteogenesis Imperfecta: A Case Report.

INTRODUCTION: Osteogenesis imperfecta (OI) is a rare genetic disorder characterized by significant bone fragility and progressive skeletal deformities. While cubitus varus (CV) is a common complication after pediatric supracondylar fractures, deformities exceeding 40° in patients with OI are exceptionally rare. This report describes a severe case managed through a staged surgical strategy to overcome challenges associated with bone fragility. CASE REPORT: A 4-year-old male with OI presented with a 45° CV deformity of the right elbow following recurrent fractures. Due to extreme bone fragility and the complexity of the 3D deformity, a staged surgical plan was implemented. The initial surgery prioritized osteotomy site stability and coronal correction using a stepped cut osteotomy. Once bone union was achieved, a second corrective wedge osteotomy was performed a year later to refine the alignment. At the final follow-up at age 7, the patient maintained a 15° carrying angle and a good range of motion. The improved alignment successfully prevented further fractures. CONCLUSION: For complex pediatric elbow deformities with underlying bone fragility, a staged approach prioritizing stability over immediate anatomical perfection is a realistic strategy. Establishing a shared understanding with the family regarding the potential necessity of multiple procedures is essential for clinical success and safety.