Revival of a Relic: Extra-Long Austin Moore Prosthesis in Revision Arthroplasty for Vancouver B3 Periprosthetic Femur Fracture—A Case Report

Background: Vancouver type B3 periprosthetic femoral fractures present significant surgical challenges due to a loose femoral stem and deficient proximal bone stock. Management typically requires modular, fluted, and tapered revision stems; however, these may be unavailable in resource-limited settings. Case Presentation: We report a 68-year-old male with a 6-year-old bipolar hemiarthroplasty who sustained a low-energy fall resulting in a Vancouver B3 fracture with stem breakage. Preoperative evaluation, including inflammatory markers and intraoperative cultures, ruled out infection. Due to limited access to modern revision implants, a non-cemented extra-long Austin Moore prosthesis was used to achieve distal diaphyseal fixation. Stability was enhanced with a trochanteric locking plate and cerclage cables. Outcomes: Postoperative recovery was uneventful, and the patient commenced supervised full weight-bearing from day 1. At 1-year follow-up, the Harris Hip Score was 78, the Oxford Hip Score was 32, the limb length discrepancy was <1 cm, and the hip range of motion was satisfactory. Radiographs confirmed maintained implant alignment and callus formation. Conclusion: In the absence of modular revision stems, an extra-long Austin Moore prosthesis with adjunctive fixation can provide short-term functional and radiological success in Vancouver B3 fractures. This approach should be considered a salvage strategy and not a standard treatment. Long-term surveillance is planned to assess implant durability.