Application of a Modular Fixing Device for Arthrodesis Following Periprosthetic Femoral Fracture With Comorbid Pathology: A Clinical Case

Abstract

This clinical case presents the management of a 68-year-old female patient diagnosed with a periprosthetic fracture of the lower third of the left femur, aseptic instability of the femoral component of the knee endoprosthesis, and defects of the left femoral condyles. The patient had a history of right knee joint arthrodesis, and severe comorbid conditions including neurogenic bladder dysfunction and class III obesity (body weight - 160 kg, height - 160 cm).
 Knee arthrodesis, namely the elimination of a joint, has a restricted field of application, especially with the collateral joint immobilized. Due to the patient's excessive body weight, knee arthrodesis was considered as a suitable option to preserve weight-bearing capacity and facilitate early rehabilitation. Various treatment options, including plate fixation, intramedullary (IM) nailing, and revision arthroplasty, were evaluated but deemed unsuitable considering the instability of the endoprosthesis and femoral condylar defects, as well as the patient's comorbidities. The patient declined amputation as a treatment option. Ultimately, a specialized modular IM nail for arthrodesis (FN) (made in Poland) was selected for surgical intervention. This implant facilitated the osteosynthesis of the femoral bone, restoration of limb length using metal cages, and removal of impaired condyles during the procedure. The modular IM nail enabled early verticalization of the patient, consolidation of the femoral fracture, and overall patient satisfaction, despite daily routine limitations.