Metaphyseal–diaphyseal Junctional Fractures of the Distal Humerus in Children: Two Case Series

INTRODUCTION: Although there are few descriptions in textbooks and it is stated that the treatment of metaphyseal–diaphyseal junctional (MDJ) fracture is difficult, there is almost no detailed description on its treatment methods and precautions. CASE PRESENTATION: We encountered two patients, 9-year-old and 1-year and 11-month-old Japanese boys, with MDJ fractures of the distal humerus, which are very rare in children. Unlike supracondylar fractures of the distal humerus, the fractures were spiral fractures, which made percutaneous pinning very difficult. Open reduction was performed using a bilateral approach with two skin incisions. Both patients recovered completely and had no problems carrying out activities of daily living or playing sports. CONCLUSIONS: For patients that are old enough to receive a locking plate, we recommend fixation using a locking plate. In cases of unilateral pinning without cross-pinning, retrograde intramedullary nailing should be considered. MDJ fractures of the distal humerus should be treated as distal humeral shaft fractures, not as subtypes of supracondylar fractures of the humerus.