Hinged knee arthroplasty in a case of non-union distal femur fracture with implant failure in an elderly individual: A case report

Abstract
Introduction: Distal femur fractures are one of the most common fractures accounting for 0.5% of all fractures with incidence of about 7/100000/year. Majority of the fractures occur in elderly population (above 60 year) with osteoporosis resulting from a low energy trauma. In the younger age group these fractures are associated with high energy trauma. Case report: A 68-year-old male presented with chief complaints of pain and deformity in right knee since 1 year. The patient had a history of distal femur fracture 2 years back for which he was operated twice with distal femur plating and bone grafting. The patient was a known case of diabetes mellitus on medication since 5 years. Radiographs of the right knee in anteroposterior and lateral views were taken, which showed distal femur fracture non-union with a broken locking compression plate with grade 4 knee arthritis. Due to the failure of osteosynthesis twice, and the patient demanding for early mobilization, a single staged procedure with implant removal followed by an arthroplasty using cemented modular distal femur endoprosthesis was planned for the patient. Conclusion: Hinged knee arthroplasty can be considered as a treatment option for patients with distal femur non-union with pre-existing severe knee arthritis. It helps in early weight bearing and return to activities of daily living.