Fixation of a Peri-Implant Distal Femur Fracture Adjacent to Cephalomedullary Nail With Retrograde Intramedullary Nail in a Capacious Canal

CASE: A 75-year-old woman presented after a low-energy fall with a minimally displaced, extra-articular peri-implant distal femur fracture at the tip of a previously placed cephalomedullary nail. Her proximal femur was in native varus, and she was profoundly osteoporotic, resulting in a capacious distal femoral metaphyseal canal and a laterally positioned distal nail tip. Because her anatomy appeared to permit safe implant overlap without excessive canal "overstuffing," a retrograde femoral nail was inserted adjacent to the existing cephalomedullary nail using a percutaneous technique. She was mobilized weight bearing as tolerated. At approximately 1 year postoperatively, documentation noted painless full knee range of motion, intact distal vascular status, and continued safe wheelchair transfers. CONCLUSION: In carefully selected patients with favorable anatomy, peri-implant distal femur fractures at the tip of a cephalomedullary nail may be stabilized with an overlapping retrograde femoral nail as one option alongside minimally invasive plating and other strategies.