Diagnostic Pitfalls and Management of Transphyseal Fractures of the Distal Humerus: A Retrospective Review of 25 Cases

Background/Objectives: Transphyseal fracture of the distal humerus (TFDH) is a rare but clinically important pediatric elbow injury that predominantly affects children under 3 years of age. Due to the radiolucent nature of the cartilaginous distal humeral epiphysis in this age group, TFDH is often misdiagnosed as elbow dislocation, supracondylar fracture, or lateral/medial condyle fracture. Time pressures, limited pediatric musculoskeletal expertise, and incomplete clinical histories in emergency settings further compound this diagnostic challenge. Despite the importance of early and accurate diagnosis to prevent complications such as cubitus varus, systematic studies on diagnostic pitfalls and strategies for improving recognition remain scarce. We therefore aim to characterize misclassification patterns, standardize radiographic cues, and evaluate management outcomes. Methods: We conducted a single-center retrospective review of 25 pediatric patients with TFDH who were misdiagnosed at initial presentation between 2012 and 2022. Clinical records, radiographic features, treatment modalities, and complications were analyzed over a minimum follow-up period of 24 months. Results: All 25 cases were initially misdiagnosed. The most common misdiagnoses were supracondylar and lateral condyle fractures (each 6/25, 24%), followed by elbow dislocation (4/25, 16%). Misclassification was primarily attributed to failure to assess global forearm–humerus alignment and misinterpretation of the radiocapitellar line. All patients underwent emergency management, with 18/25 (72%) receiving closed reduction and percutaneous K-wire fixation, and 7/25 (28%) undergoing closed reduction and cast immobilization. Cubitus varus developed in 5/25 (20%) overall and was more frequent after closed reduction with cast immobilization (3/7, 43%) than after K-wire fixation (2/18, 11%). Overall, 92% achieved excellent functional outcomes according to the Mayo Elbow Performance Index (MEPI). The implementation of a targeted curriculum improved diagnostic accuracy among trainees from 70% to 100%. Conclusions: TFDH poses substantial cognitive and radiographic diagnostic challenges. A structured radiographic assessment, early senior review, and targeted education may improve recognition and outcomes. These findings offer actionable insights to enhance diagnostic accuracy and optimize care for this vulnerable patient population.