Abstract
Monteggia equivalent fractures, a spectrum of proximal ulnar and radial injuries extending beyond classic Monteggia patterns, are rare and diagnostically challenging, particularly in adults. Delayed presentation further complicates management and increases the risk of long-term morbidity. This report details a case series of two adult patients with Type I Monteggia Equivalent fractures, one with a delayed presentation, successfully treated with open reduction and internal fixation (ORIF) of the radial fracture. We aim to elucidate effective diagnostic and treatment principles for this specific injury pattern, emphasizing favorable outcomes and highlighting the unique aspects of adult presentations and the management of delayed cases. We present two male patients, aged 20 and 24, with Bado Type I Monteggia Equivalent fractures. The first patient had a one-month-old injury, while the second presented acutely. Both underwent ORIF of the radius using a 3.5 mm dynamic compression plate. Anatomical restoration of radial length and alignment consistently led to spontaneous and stable reduction of the radiocapitellar joint in both instances, confirmed intraoperatively and at follow-up. These cases reaffirm that meticulous anatomical fixation of the radial fracture is pivotal in treating Monteggia equivalent lesions, facilitating spontaneous radial head reduction even in situations with delayed presentations. The outcomes, characterized by Mayo Elbow Performance Scores (MEPS) of 100 at 6-month follow-up, align with principles advocating for stable surgical fixation to restore joint stability and function. This series contributes specific Introduction and Importance: Monteggia equivalent fractures, a range of proximal ulnar and radial injuries extending beyond classic Monteggia patterns, are rare and difficult to diagnose, especially in adults. Delayed presentation further complicates management and raises the risk of long-term complications. This report presents a case series of two adult patients with Type I Monteggia Equivalent fractures, one with a delayed presentation, successfully treated with open reduction and internal fixation (ORIF) of the radial fracture. Our goal is to clarify effective diagnostic and treatment principles for this specific injury pattern, emphasizing successful outcomes and highlighting the unique aspects of adult cases and managing delayed presentations. Data on adult Type I Monteggia equivalent fractures, a less documented variant, underscores the potential for excellent results despite delayed presentation. Notably, Case 1 demonstrates that even after a one-month delay, precise anatomical reduction of the radius can achieve stable radiocapitellar joint reduction without the need for extensive soft tissue releases, which may be a point of departure from some pediatric literature. Anatomical ORIF of the radial fracture is a highly effective treatment for Type I Monteggia Equivalent lesions, yielding excellent functional outcomes and complete recovery. A high index of suspicion, prioritization of anatomical radial fixation, and the understanding that favorable results can be achieved even with delayed treatment are critical for optimal patient care. This series specifically reinforces the efficacy of this approach in adult patients and in chronic settings, offering valuable insights into a complex and often overlooked injury pattern.