Periprosthetic fractures of the femur after total knee arthroplasty. A literature review and treatment algorithm.

Supracondylar femur fractures after total knee arthroplasty can significantly alter the quality of knee arthroplasties and provide a challenging problem for the treating surgeon. A review of the literature and an approach to the treatment of these periprosthetic fractures is presented. The predisposing factors, mechanisms of injuries, and characteristics of the fractures are identified. A classification system is proposed based on a modified Neer grading system, the degree of comminution, and the location and character of the fracture. A treatment algorithm is developed and based on acceptable alignments of less than 5 mm translations, angulations less than 5 degrees-10 degrees, minimal rotation, less than 1 cm of femoral shortening, and proper tibiofemoral prosthetic joint alignment.