Distal radius fracture after proximal row carpectomy.

Introduction: We encountered a patient with distal radius fracture (DRF) after proximal row carpectomy (PRC). The mechanism of the DRF after PRC is discussed in this report.

Presentation Of Case: The patient was a 73-year-old female who had undergone PRC due to Kienböck disease before. The wrist range of motion was: 45° on dorsiflexion and 20° on flexion. DRF has occurred at 3 years after PRC. The fracture type was extra-articular fracture. Osteosynthesis was performed using a volar locking plate. No postoperative complication developed, the Mayo score was excellent at 6 months after surgery, and the daily living activity level recovered to that before injury.

Discussion: Since the wrist range of motion decreased and the lunate fitted into the joint surface after PRC, making the forearm join with the hand like a single structure, pressure may have been loaded on the weak distal end of the radius from the dorsal side, causing volar displacement and fracture.

Conclusion: The pressure distribution and range of motion of the radiocarpal joint after PRC are different from those of a normal joint, and the mechanism of fracture also changes due to PRC.