PurposeStudy of a biplanar crossed pin construct by two crossed Kirschner wires in the management of displaced extension type supracondylar humeral fractures in children.MethodsSixty-four patients with such fractures were included and treated according to the study protocol: after achieving closed reduction under general anesthesia with fluoroscopic control, two crossed Kirschner wires of equal diameter were inserted percutaneously. The first lateral wire tracts from the posterolateral corner of the epicondyle to the anteromedial cortex proximally. Then, the medial wire is inserted from the anteromedial corner of the epicondyle to the posterolateral cortex proximally after crossing the fracture site. Thus, a biplanar crossed pin construct was achieved, as each wire had two separate fixation points and the crossed construct was achieved not only in the coronal plane but also in the sagittal plane. Every effort was made to get this construct right at the very first attempt without repetition.ResultsTwo patients were lost to follow-up during the first postoperative year. The mean follow-up for the remaining 62 patients was 14.5 months (range 6–24 months). At the final follow-up, using Flynn’s overall modified classification, the clinical result was considered to be satisfactory in 60 (96.8 %) patients and unsatisfactory with poor result in two (3.2 %) patients. Technical error was thought to be the cause of the poor results. There were no postoperative neural or vascular complications.ConclusionA biplanar crossed pin construct achieved by two Kirschner wires crossed in the coronal and sagittal planes is efficient to stabilize a displaced extension type supracondylar fracture of the humerus in children.