Current methods and treatment options for interprosthetic femur fracture: An overview

As life expectation is prolonged and the elderly population increases, we are witnessing a growth in the number of prosthesis implanted; therefore, an increase in interprosthetic femoral fractures can be expected in the next future. For this reason, a proper and specific classification system needs to be. Nowadays, depending on the localization of the fracture, Vancouver or Rorabeck classifications are used, and some attempts have been made to create a new one or adjust and adapt the previously mentioned systems. However, there is no unique classification system that is accepted worldwide. The goal would be a classification that permits identifying the correct surgical treatment based on the type of interprosthetic femoral fracture. A pragmatic grading scale to provide a standardised approach, so that the best possible outcomes could be achieved. Despite minimal diffusion, in our opinion the Pires classification system should be universally accepted and used. Interprosthetic femoral fractures (IFF) are fractures occurring between two prosthetic components implanted in the same femur. They are considered as a developing issue over the last few years in the trauma field, due to the increase in the aging population and, as a consequence, the increase in joint prostheses implanted. Although the actual incidence remains unknown, Valle Cruz et al. reported an incidence of 8.8% 1,2. IFFs represent a genuine challenge for orthopedic surgeons and are associated with high rates of mortality and revision surgery 3. The first reported case in the literature about surgical treatment of this kind of fracture dates to 1995, when Dave et al. treated an interprosthetic fracture using a Mennen’s plate 4. Subsequent works focused on the investigation of IFF risk factors, epidemiology, classifications, biomechanics, surgical approaches and techniques, results and outcomes. However, data in literature do not currently provide an official classification or a gold standard treatment. Moreover, studies are limited by cohort size, standardization and level of evidence; the creation of a systematic approach appears challenging. Given the current trend of the aging population, the number of implanted prostheses is increasing, and thus the number of patients at risk of interprosthetic femoral fractures; surgical treatment of such fractures is unavoidably destined to become a routine procedure. In order to obtain appropriate standardization of classification systems, guidelines, indications, approaches and rehabilitation steps, a deeper insight on all aspects related to interprosthetic femoral fractures is needed. This is of great importance for several reasons: the severity of the injury and its substantial impact on patient morbidity and mortality; potential negative outcomes; level of surgical skills and knowledge needed to appropriately provide satisfactory treatments. The aim of the present study is to carry out a narrative literature review on interprosthetic femoral fractures, including all relevant aspects and focusing primarily on classification, biomechanics and surgical indications; to sum up current knowledge about this type of fracture to highlight the most up to date evidence presented in literature and reporting our experience and considerations. An electronic search was performed throughout the Pubmed, Embase and Cochrane databases. Studies were analyzed without concern for the time of publication.