Fig. 1

a Planned opening-wedge osteotomy with shaft (orange) and distal fragment (cyan) with optimal plate position (yellow). b Pre-reduction guide (pink) with optimal fit on the malunited distal radius with cutting slit. c Ramp guide (gray) attached to malunited distal radius with fixated plate (yellow) on the slope. d Fixated plate (yellow) on the distal fragment before completing the osteotomy