Diagnosis and treatment of a head-neck separation type of Monteggia equivalent fractures in children / 中华创伤骨科杂志

ABSTRACT

Objective:To explore the clinical characteristics and treatment of a head-neck separation type of Monteggia equivalent fractures in children.Methods:From March 2016 to February 2019, 12 children sought medical attention at Pediatric Orthopedic Hospital, Honghui Hospital Affiliated to Xi'an Jiaotong University for a head-neck separation type of Monteggia equivalent fractures. They were 8 boys and 4 girls, aged from 3 to 14 years (average, 8.3 years). All cases were treated with closed reduction, deformity correction and plaster fixation at emergency department after X-ray examination. In line with the treatment principles for Monteggia fractures, after the ulnar length was first restored and stabilized, a proper fixation method was chosen according to the location and type of the ulnar fracture, followed by treatment of the radial neck fracture. The fracture union and complications were evaluated according to the X-ray films after operation, and the therapeutic efficacy was evaluated according to the Mayo elbow performance score (MEPS) at the final follow-up.Results:The head-neck separation type of Monteggia equivalent fractures in children was characterized by a fracture of ulnar diaphysis or metaphysis and a fracture of the radial neck with complete separation of the head and neck, a longitudinal axis of the radius off the capitellum center at the distal fracture end but normal proximal humeroradial relationship. The fractures were classified into 2 types depending on the angulation direction of the ulnar fracture and the direction of distal displacement of the radial neck fracture 7 cases belonged to the extension-valgus type and 5 cases to the flexion-varus type. The 12 patients were followed up for 8 to 38 months (average, 16.0 months). Of the ulnar fractures, one was treated with closed reduction and Kirschner wire fixation, 4 with elastic intramedullary nail fixation, 5 with plate fixation, one untreated, and one with manual reduction only. Of the radial neck fractures, 11 were treated with closed reduction and elastic intramedullary nail fixation, and one with open reduction and K-wires fixation. All fractures got united after 8 to 12 weeks (mean, 9.6 weeks). The time for removal of internal fixation ranged from 12 to 50 weeks (mean, 31.2 weeks). Avascular necrosis occurred in one case and bulk formation of proximal metaphysis in another. By the MEPS at the final follow-up, the therapeutic efficacy was excellent in 10 cases, good in one and fair in one.Conclusions:The head-neck separation type of Monteggia equivalent fractures in children is different from common Monteggia fractures or radial neck fractures, because its clinical manifestations are characterized by a fracture of ulnar diaphysis or metaphysis and a fracture of the radial neck with complete separation of the head and neck, a longitudinal axis of the radius off the capitellum center at the distal fracture end but normal proximal humeroradial relationship. The treatment options for ulnar fractures include closed reduction with Kirschner wire fixation, elastic intramedullary nailing, open reduction and bone plate fixation or no fixation, while radial neck fractures are mostly treated by closed reduction and elastic intramedullary nailing. Early functional exercise can lead to satisfactory clinical outcomes.