Avascular Necrosis After a Supracondylar Humerus Fracture Resulting in Capitellar Dissolution and Fishtail Deformity:...

A six-year-old boy sustained a displaced and rotated supracondylar humerus fracture (SCHF) after falling from the monkey bars. He underwent closed reduction and percutaneous pinning using two lateral-entry Kirschner wires. He had an uneventful postoperative recovery and returned to full normal activity. A routine follow-up radiograph obtained one year after the injury showed that the capitellum ossific nucleus was absent, presumably due to dissolution caused by avascular necrosis (AVN). He also had AVN of the trochlea. Despite these radiographic findings, he was completely asymptomatic. He was treated with activity restrictions to avoid upper-extremity weight-bearing for two years. Eleven years after the fracture, he remained asymptomatic, with an elbow range of motion of 5°-135°. His radiograph demonstrated a fishtail deformity of the distal humerus resulting from the effects of AVN on the distal humeral growth plate.