Background: The aim of this work was to develop a three-dimensionally (3D) printed brace for the acute treatment of dorsally dislocated and correctly reduced distal radius fractures (DRF). The hypothesis was that a brace shaped to the mirror image of the contralateral (non-fractured) wrist will have an optimal anatomical fit, resulting in improved comfort and lower rates of secondary fracture displacement. Method: Validation: the circumference of both wrists and comfort of the brace were studied in healthy volunteers and effectiveness of the brace was evaluated in an ex vivo fracture model. Clinical study: the brace was tested for comfort and effectiveness in patients with a well reduced unstable DRF. Results: Validation: the circumference of both wrists may be different, the brace retained the reduction in the ex vivo fracture model and was well tolerated in the volunteers. Clinical study: in DRF patients comfort scores were lower and pain scores higher compared to the healthy volunteers. After 3 and 5 weeks all patients were independent in ADL according to the Katz-index. Posttraumatic swelling subsided in the first week. In two of the five patients secondary fracture dislocation occurred. Conclusions: Treatment of a dislocated DRF in the acute setting (day one) with a custom-made 3D printed brace, anatomically modelled from a 3D scan of the contralateral wrist, is possible. Difference between both wrists and posttraumatic swelling must be adapted for. The high rate of secondary fracture displacement led to early discontinuation of the study and a small sample size.