Purpose of the study: Within the framework of a regional study, we compared the efficacy of pinning using the PY technique and the Kapandji method for the treatment of fractures of the distal radius with posterior displacement.

Material and methods: This was a prospective study designed as a phase III randomised therapeutic trial in parallel groups. An open monocentric study with multiple operators compared the PY and Kapandji techniques. Two comparable groups were established: the PY group and the Kapandji group (K) for which we measured: quality of reduction using the radiographic frontal and sagittal radial inclination (FRI and SRI), radial length and inferior radioulnar index. Objective and subjective functional outcome assessed range of motion and the DASH and Jakim scores. The quality of the intra-articular reduction of articular fractures was assessed arthroscopically at the time of implant removal during the sixth week.

Results: The series included 97 patients followed for one year. The preoperative FRI was 15.17 with mean posterior shift of −19.2. At one year, the RI was 25.5 in the PY group versus 22.6 in the K group (p=0.009) and the SRI 10.5 in the PY group versus 3.7 in the K group (p=0.04). For fractures with a posteromedian fragment and Gerard-Marchand fractures, the DASH at one year was 2 in the PY group versus 32 in the K group. The Jakim score was 71 in the PY group versus 58 in the K group (p=0.03) for posteromedian fragment fractures. The arthroscopic control at six weeks of articular fractures did not reveal any significant difference in intra-articular reduction. There were no tendon tears in this series.

Discussion: This series shows the quality of pin fixation for wrist fractures, comparable with plating. It emphasizes the importance of adapting the type of pinning to the fracture type and the patient.

Conclusion: Treatment of fractures of the distal radius with posterior displacement with pin fixation remains a treatment of choice, reserving PY osteosynthesis for fractures with a posteromedian fragment and Gerard-Marchand fractures and Kapandji osteosynthsis for simple Colles fractures.