Supplementary Material

Files in this Data Supplement:

• PDF file - A table showing the clinical details of all study subjects
• MPG file - Video 1: Details of the Simulation Technique (Case 9). A computer program was used to manually superimpose the distal part of the malunited radius (yellow) to the corresponding part of the mirror image of the contralateral, normal bone (white), which was followed by surface-based registration²⁰. The same procedure was then applied to the proximal part. By calculating the difference between the positions of the proximal and the distal parts, we acquired a matrix for the displacement, i.e., the deformity of the distal part relative to the proximal part. This displacement can be further defined in terms of rotation around and translation along a certain axis with use of the screw displacement axis technique^21-23 (See Video 2). Thus, bone deformity can be determined as the rotation around and translation along one unique axis. When the translation is small, the screw displacement axis can be regarded simply as the deformity axis. In the present case, correction of the radius is to be completed by performing a rotational osteotomy through a plane that is perpendicular to the deformity axis (see also Fig. 2).
• MPG file - Video 2: Screw Displacement Axis. In a three-dimensional space, every body motion can be expressed in terms of rotation around and translation along one unique axis, or the screw displacement axis^21-23.
• MPG file - Video 3: Surgery with Use of a Custom-Made Osteotomy Template (Case 9). After the template was fit onto the bone surface, it was fixed with Kirschner wires through the drill-holes, and the bone was divided through the cutting slit on the template. The template was removed, and the two sets of Kirschner wires were made parallel to each other by rotating the distal segment. A reduction guide was used to maintain the reduced position.