Combined Antero-Posterior Inverted-U Metaphyseal and Open-Wedge Medial-Epiphyseal Osteotomy for Advanced Blount Disease

Abstract

Background: Blount disease is frequently associated with deformities that may not be adequately corrected by a single metaphyseal osteotomy. This study evaluated the outcome of a combined metaphyseal and epiphyseal osteotomy in severe cases. Methods: We prospectively evaluated the outcome of combining the antero-posterior inverted-U metaphyseal osteotomy with a medial open-wedge hemi-epiphyseal osteotomy in eighteen patients (27 tibiae) with Stage IV to VI Blount disease. Results: The average age of patients was 9 years (ranging from 5 to 17). The tibio-femoral angle improved from 43˚ varus (Range: 34˚ - 78˚) to 2˚ varus (Range: 5˚ valgus to 8˚ varus). The metaphyseal-diaphyseal angle improved from 36˚ to 8˚ varus. Internal tibial torsion improved from 39˚ to 2˚. All the patients were able to achieve 110˚ of knee flexion in a year. Conclusion: In conclusion, the combined metaphyseal and epiphyseal osteotomy satisfactorily corrected tibiofemoral and metaphyseal-diaphyseal varus and internal tibial torsion without recurrence in patients with severe Blount disease. Level of Evidence: IV.