Bilateral Periprosthetic Knee Fracture with the Right Floating Total Knee and Left Periprosthetic Patella Fracture Management Strategy: A Case Report

INTRODUCTION: Periprosthetic fractures (PPFs) in total knee replacement are an uncommon condition. The floating knee injury around total knee arthroplasty (TKA) is even rare and poses challenges in management. Incidence is increasing due to growing primary joint arthroplasties and revision procedures. We report a case of bilateral PPF with a floating total knee. CASE REPORT: A 74-year-old female involved in a violent car accident sustained bilateral knee injuries, facial, and hand injury. In the emergency room, the initial resuscitation and trauma protocol stabilization were done and she was provisionally immobilized for her limb injuries. She presented with the right-sided floating total knee involving periprosthetic periarticular comminuted distal femur fracture and midshaft comminuted fracture tibia fibula. The patient also had left knee lower pole periprosthetic patellar fracture. The patient had a history of bilateral TKA around 2 years back. She underwent surgical management of the right floating total knee by stabilization of distal femur fracture and tibial shaft fracture fixation with locking plates. She underwent primary autologous bone grafting for both fracture sites. The left knee patellar fracture was managed conservatively in a brace. At 8 months follow-up, the patient was pain free and had consolidation of fractures. The patient walked without any walking aids. At 18 months, she had regained her pre-injury functional status. CONCLUSION: Each fracture in a floating total knee injury is unique and treatment should be decided based on individual analysis and the extent of soft-tissue injuries. An uncommon occurrence highlights the complex injury patterns involving PPF requiring individualized case specific management strategy.