Novel Medial Application of a Locking Attachment Washer in Managing Hoffa Fracture Non-union With Peri-Implant Femoral Fracture: A Case Report.

Non-union of Hoffa fractures is an uncommon but challenging complication due to the intra-articular nature and limited bone surface area available for fixation. When compounded by a peri-implant distal femur fracture, treatment becomes significantly more complex, particularly in the presence of previous hardware. We present a rare case of a 59-year-old male with a chronic non-union medial Hoffa fracture complicated by a peri-implant fracture at the proximal end of a distal femoral locking plate. Definitive management involved implant removal, retrograde intramedullary femoral nailing using the RFN-Advanced™ system, bone grafting via the Reamer-Irrigator-Aspirator technique, and the novel medial application of a lateral locking attachment washer (LAW) to stabilize the Hoffa fragment. This configuration provided dual-plane stability and facilitated successful fracture union. Radiological union was observed at three months postoperatively, with the patient achieving a 0-130 degrees range of motion and a Knee Society Score of 90/100 at one year. No complications were reported, and functional recovery was excellent. The medial deployment of a lateral LAW in conjunction with a retrograde femoral nail represents a biomechanically sound and surgically viable solution for complex distal femoral fracture patterns involving Hoffa non-union and peri-implant fractures. This technique broadens the applicability of the LAW and may serve as a reference for future cases with similar dual pathology.