Hook Plate Fixation of an Isolated Pisiform Fracture with a Small Proximal Fragment: A Case Report.

Introduction: The report describes hook plate fixation for an isolated, displaced pisiform fracture characterized by a small proximal fragment. Case Report: A 64-year-old woman presented with ulnar-sided wrist pain after a fall. Radiography and computed tomography revealed intra-articular displacement with mild comminution. Open reduction and internal fixation using a 1.2-mm hook plate resulted in a stable anatomical reduction without the need for fragment excision. Postoperatively, the wrist was immobilized in a volar splint in neutral position for 3 weeks, after which progressive mobilization was initiated. At 12-month follow-up, the patient was pain-free with wrist extension of 85° and flexion of 75°. Grip strength was 29.6 kg on the operated side, while 24.3 kg on the contralateral side. Patient-reported outcomes were excellent, indicating satisfactory functional recovery and pain relief. Radiographs confirmed bone union and anatomical alignment, with no evidence of pisotriquetral degenerative changes. Conclusion: Hook plate fixation may represent a feasible joint-preserving alternative for select comminuted pisiform fractures with small fragments, offering stable fixation and enabling relatively early rehabilitation.