Periprosthetic fractures after total knee arthroplasties.

UNLABELLED: The management of periprosthetic fracture around the knee remains a challenging problem. The objective of this article was to review the general concepts, treatment algorithms, and the overall treatment outcomes of femoral and tibial periprosthetic fractures after total knee arthroplasty. This article aimed to highlight the deficiencies of the current classification systems that fail to provide a guideline for selection of appropriate treatment options. We proposed a new classification system for periprosthetic femoral fractures that takes into account the status of the prosthesis, the quality of distal bone stock, and the reducibility of the fracture. Type I fractures are those occurring in patients with good bone stock with the prosthesis being fixed and well positioned. Type IA fractures are either nondisplaced or easily reducible and can be treated conservatively. Type IB fractures are irreducible and require reduction and internal fixation. Type II fractures are defined as those occurring also in patients with good bone stock and being reducible, but either the components are loose or malpositioned. These fractures are treated by revision arthroplasty. Type III fractures are reducible or irreducible fractures that occur in patients with poor bone stock and in the vicinity of loose or malpositioned components. These fractures are treated by distal femoral replacement. LEVEL OF EVIDENCE: Therapeutic study, level V (expert opinion). See Guidelines for Authors for a complete description of levels of evidence.