Comparison of patient-specific implants with standard plates after 3-D-planned corrective osteotomy for distal radial malunions

We compared 3-D-printed patient-specific implants (PSIs) with standard palmar locking plates for radiological accuracy after extra-articular corrective osteotomy for malunited distal radial fractures. Eleven patients were operated on with a PSI. Additionally, a plastic printed model of each patient was operated on with a standard plate <i>in vitro</i>. Three months postoperatively, radial alignment in patients and models was compared with the preoperative ideal planning using CT scans. Patients with PSIs showed smaller rotational deviations (median 7°) compared with standard plate models (9°). Deviations in the direction of translation, radial inclination, palmar tilt, radial height and ulnar variance were also smaller or similar with the PSI compared with the standard plates. The preoperative grip strength with a median of 8 kg and a Patient-Rated Wrist Evaluation score of 44 improved to 23 kg and 3 points, respectively, at a median follow-up of 13.5 months. Our results indicate superior radial alignment after PSI compared with standard plates, but the clinical relevance of these findings needs to be investigated.<b>Level of evidence:</b> IV.