Transphyseal Separation of Distal Humerus Extending to the Lateral Condyle Mimics Isolated Lateral Condyle Fracture in Children: A Case Report.

Introduction: The most common injuries around the elbow are the supracondylar humerus, followed by lateral condyle fractures. Transphyseal separations are uncommon, especially in children older than 3 years. Type 3 Weiss lateral condyle fractures appear similar to transphyseal separations on standard radiographs but have articular incongruity and may need open reduction. In comparison, transphyseal separations often need only closed reduction.

Case report: We present a case of injury of the distal humerus in a 4-year-old child sustained due to a fall on the outstretched hand.Diagnoses, Treatment and Outcome: Transphyseal Separation and Lateral condyle humerus fractures were the differential diagnoses. The patient was treated with closed reduction and lateral pinning. The child had complete pain-free movements at the elbow at 3 and 12 months follow-up. With the help of the case report, we describe the importance of intraoperative post-reduction arthrograms to differentiate type 1, type 2 Weiss lateral condyle, and transphyseal separations from type 3 Weiss lateral condyle fractures.

Conclusion: Transphyseal separation of the distal humerus can mimic lateral condyle fracture in children. Proper pre-operative radiographs and intraoperative arthrogram can avoid unnecessary open reduction and complications. This article presents a flowchart to help make a better decision regarding management.