Title: Neglected Monteggia Lesion Revealed by an Ipsilateral Fracture of the Distal Radius: A Case Report
Authors: Zajli Driss, Lahrach Kamal, Abaydi Anass, Lahlou Hamza, Radi Jihad, Boutayeb Fawzią
Volume: 10
Issue: 9
Pages: 84-89
Publication Date: 2026/09/28
Abstract:
Introduction: A radial shaft fracture associated with dislocation of the distal radioulnar joint defines a Galeazzi fracture-dislocation. In contrast, an ulnar fracture associated with radial head dislocation defines a Monteggia lesion. The association of a distal radius fracture with radial head dislocation is unusual and may cause diagnostic confusion. Misinterpreting the acute or chronic nature of the dislocation may lead to unnecessary or unplanned procedures. Case presentation: We report the case of a 34-year-old man involved in a road traffic accident. An acute comminuted fracture of the distal radius revealed a neglected Monteggia lesion dating from childhood. The main diagnostic challenge was to determine whether the radial head dislocation was acute or chronic. The presence of a distal radius fracture alone could not establish the age of the dislocation, since an acute radial head dislocation may occur when the distal radial injury acts as a second disruption of the forearm ring. Chronicity was established based on several morphological findings: remodeling and osteophyte formation of the radial head, a well-corticated deformity of the proximal ulna without an acute fracture line, chronic radiocapitellar incongruity confirmed by computed tomography, and intraoperative irreducibility of the radial head. The distal radius fracture was treated by open reduction and internal fixation using an anatomical locking plate through an anterior Henry approach. The painless and well-tolerated chronic radial head dislocation was managed non-operatively with regular follow-up. Results: At the six-week follow-up, radiographs showed ongoing union of the distal radius fracture. Elbow flexion-extension was full and painless. Limitation of forearm pronation and supination persisted, without pain or neurological deficit. Conclusion: This case highlights the importance of systematically examining the elbow, forearm, and wrist in patients with a forearm fracture. Associated fractures and dislocations should not only be identified but also dated using clinical findings and radiological signs of chronicity. This approach helps distinguish an old deformity from a recent injury and avoids inappropriate treatment.