Percutaneous transphyseal intramedullary Kirschner wire (K-wire) fixation was performed for diaphyseal fracture of the forearm in 84 children. In 60 patients (71%) closed reduction was performed, while in the remaining 24 (29%) closed reduction was supplemented with a mini-open reduction The K-wire was inserted transphyseally through the radial styloid or the Lister tubercle for the radius, and through the tip of the olecranon for the ulna. With an average follow-up of 70 months and a minimum follow-up of 2 years, all the patients reviewed were found to have good functional results; none had nonunion, deep infection, or premature physeal closure. Moreover, initial preoperative translation of the fracture of more than 100% displacement was found to be associated with a significantly higher chance of requiring a mini-open reduction. The authors concluded that percutaneous transphyseal intramedullary K-wire pining for forearm diaphyseal fracture in children is a convenient, effective, and safe operation, without any deleterious effects on subsequent growth of the distal radius.