Nonunion of forearm shaft fractures in children after intramedullary nailing.

The elastic stable intramedullary nailing (ESIN) is the current treatment of choice for unstable forearm shaft fractures in children. There is no large study on paediatric nonunion of forearm shaft fractures in children after intramedullary nailing. There are only sporadic reports on nonunions after ESIN in children. The aim of this study was to define predisposing factors of nonunions in paediatric forearm fractures. All children who had been treated for forearm fractures by ESIN in our hospital from 1990 to 2006, and all children treated elsewhere surgically and being followed up at our institution were included in the study. In these children, we identified all patients who did not show bony consolidation of the fracture after 6 months from ESIN. Over a period of 16 years, 537 patients were primarily treated in our hospital and 55 children had been initially treated in a different institution. Six children were identified to fulfill the criteria of having developed a pseudarthrosis. Of these six children, three patients had been primarily treated in another hospital and three were our original patients. The average age was 11.1 years (9-14 years). There were only pseudarthroses of the ulna to be observed. In five children, the pseudarthrosis was in the middle third and in one patient in the distal third of the ulna. There were five closed fractures and one first-degree open fracture. Five times an open reduction of the ulna had been performed because closed reduction and insertion of the ESIN was impossible, whereas the radius had been treated closed in five cases and open in one case for intramedullary stabilization. Three cases were refractures, in one child it was a second refracture. In one case, we identified a technical error as cause of the development of the pseudarthrosis. Four children needed a revision surgery. In these children, the ulna was plated. Two patients showed spontaneous healing of the pseudarthrosis. In five patients, there was a hypertrophic pseudarthrosis present and in one case was hypotrophic pseudarthrosis. The reintervention was necessary because of increasing deformity in four patients and implant failure in one case. In conclusion, Non-unions after forearm fractures are observed in children and adolescents mainly in the middle third of the ulna. With the need of initial open reduction or the presence of an open fracture in the first instance, the risk of developing a pseudarthrosis. It may also be higher in such cases, which represent a refracture. Despite the small risk of developing a pseudarthrosis after forearm fracture, the indication for ESIN is clear. The surgical trauma needs to be as minimal as possible in cases with open reduction with as little as possible compromise of the blood circulation of the affected bone.