Refracture of pediatric both-bone diaphyseal forearm fracture following intramedullary fixation with Kirschner wires is likely to occur in the presence of immature radiographic healing

Purpose: Refracture of pediatric both-bone diaphyseal forearm fractures (PBDFFs) may occur, even if the fractures are treated with intramedullary nailing. The purpose of this study was to investigate the risk of refracture of PBDFFs treated with intramedullary Kirschner wires (K-wires), which are commonly used in our clinic. Methods: The present multicenter retrospective study included 60 consecutive patients with 60 PBDFFs who were treated with intramedullary K-wires at 5 hospitals between 2007 and 2016. The age of the patients at the time of the primary fracture ranged from 2 to 15 years. The characteristics of the primary fractures and treatment course were evaluated. Results: Refracture occurred in 6 patients (10.0%). Three of the patients were young girls; the other 3 were adolescent boys. Refractures were caused by falling or during sports activity. The duration from primary fracture to refracture ranged from 46 to 277 days, and in 5 of the 6 patients refractures occurred within 6 months. Although we were unable to identify factors significantly contributing to refracture (e.g. fracture type or treatment procedures), radiographs at the latest visit before refracture demonstrated findings of immature healing in five of six patients. Both K-wires and external immobilization had been removed before complete fracture healing in a large proportion of patients with refracture (80.0%). Conclusions: Refracture of PBDFF may occur several months after treatment with intramedullary K-wires if the primary fracture shows immature healing. Physicians should pay special attention when judging radiographic fracture healing, even when the fracture is deemed to have clinically healed.