ABSTRACT
Objective:To discuss the atypical radiological features of posterior Monteggia fracture and appropriate treatment of the fracture.Methods:A retrospective study was conducted of the 12 patients who had been treated for posterior Monteggia fracture with atypical radiological features at Department of Orthopaedics and Traumatology, Beijing Jishuitan Hospital from July 2019 to December 2020. They were 7 males and 5 females, aged from 18 to 65 years (mean, 46.5 years). Their elbow X-ray and CT scan features included unidentified upper ulnoradial dislocation, presence of triangular or quadrilateral butterfly fracture pieces in front of the fracture end at the level of ulnar coronal process, normal humeroradial joint or forward dislocated radial head, comminuted fracture or anterior edge fracture of the radial head, or backward angulated fracture of the radial neck. The proximal ulnar fractures were fixated with olecranon anatomical locking compression plate or with assistant kirschner wire and tension band fixation; the ulnar coronoid process fractures were fixated with kirschner wire or lag screws or a mini-plate; the radial head fractures were fixated with headless compressing screws or a mini-plate or treated with radial head replacement; the severe injury to the radial collateral ligament was repaired with a suture anchor. Fracture union time, complications and range of elbow motion at the final follow-up were recorded. Elbow function was assessed by Mayo elbow performance score (MEPS).Results:All patients were followed up for 6 to 28 months (mean, 16.4 months). All fractures achieved bony union after 12 to 19 weeks (14.6 weeks). The final follow-ups revealed the following: the range of elbow flexion and extension ranged from 75° to 145°, averaging 100.5°; the range of forearm rotation ranged from 80° to 155°, averaging 132.0°; the MEPS ranged from 50 to 100 points, averaging 86.2 points and yielding 5 excellent, 4 good, 2 fair and 1 poor cases. Elbow stiffness developed in 3 cases.Conclusion:Understanding the atypical radiological features of posterior Monteggia fracture can promote better diagnosis and treatment of the posterior Monteggia fracture in clinic.