RESUMEN
Background: In chronic radial head dislocation cases, the radial head may enlarge and become dome-shaped. To date, there is no validated tool to quantify radial head deformation and predict its influence on surgical outcomes. This study assesses the potential value of volume and surface calculations obtained by quantitative three-dimensional computed tomography scanning (Q3DCT) in the workup for a corrective surgery in pediatric patients with missed Monteggia lesions. Material and methods: Ten consecutive pediatric patients with a missed Monteggia lesion were included (2012-2020). The volume and articular surface size of the radial head were calculated using Q3DCT, and a three-dimensional reconstruction of the articular surface relief was depicted in a heat map. The head-neck ratio was calculated and compared to Q3DCT data of missed Monteggia patients and their age-/sex-matched controls. Results: The radial head volume and radial articular surface size did not differ significantly between patients with missed Monteggia lesions and age-/sex-matched controls (volume 1487 mm3 vs. 1163 mm3, P = .32; articular surface size 282 mm3 vs. 236 mm3, P = .33). Optically, heat maps of the articular surface of missed Monteggia patients did not differ notably from control heat maps. A higher head-neck ratio correlated to a larger radial head volume (Pearson r = 0.73; P = .2). Discussion and conclusion: Q3DCT may be an interesting tool in the preoperative workup of pediatric missed Monteggia lesions. Prospective research with larger cohort sizes and data that compares the affected side to the contralateral elbow is needed to assess its true clinical potential.
RESUMEN
Introduction: Monteggia fracture-dislocations are rare and complex injuries that usually involve a fracture of the proximal ulna associated with a proximal radioulnar and radiocapitellar joint dislocations. These injuries comprise <1% of all pediatric forearm fractures. We report on a pediatric Monteggia fracture-dislocation variant that included an irreducible divergent ulnohumeral joint dislocation, an irreducible anterior radial head dislocation, and a proximal and distal radius and ulna fracture. Case Report: A 6-year-old female came to our emergency room with a right elbow and forearm pain and deformity after a fall from a slide on the same day. X-rays revealed a divergent ulnohumeral joint dislocation, an anterior radiocapitellar joint dislocation, a proximal radioulnar joint dislocation, and a proximal and distal ulna and radius fracture. Closed reduction under sedation in the emergency room was not successful, with persistent ulnohumeral, ulnoradial, and radiocapitellar joint dislocations. The patient was taken to the operating room the next morning. She underwent open reduction and internal fixation of the proximal ulna fracture with a one-third tubular locking plate, and radial head dislocation open reduction. A stable reduction of the ulnohumeral joint was only possible after the fixation of the proximal ulna fracture. The most stable position for the radiocapitellar joint after its open reduction was at 70o of elbow extension and full forearm supination; the patient was casted in that position for 6 weeks. Conclusion: Pediatric Monteggia fracture-dislocations are rare and complex childhood fractures, and new variants of this injury can have even more complex presentations. Open reduction and stable internal fixation addressing all components of this injury will lead to an excellent outcome.
RESUMEN
Monteggia fracture-dislocations in the pediatric population have unique patterns of injury that require distinct considerations in diagnosis and management. When appropriately diagnosed and treated early, acute pediatric Monteggia injuries have favorable outcomes. Missed or inadequately treated injuries result in chronic Monteggia lesions that require more complex surgical reconstructions and are associated with less predictable outcomes. This article reviews the classification, diagnosis, and treatment of acute and chronic pediatric Monteggia injuries as well as the controversies there in.