Femoral shaft nonunions are disabling complications of fractures, with relevant socioeconomic and psychological impact. The incidence of femoral shaft nonunions is not negligible, ranging between 1% and 10% after intramedullary nailing, but can exceed 20% in case of subtrochanteric fractures. Treatment options are influenced by pathomechanical, anatomical, and clinical factors. Hypertrophic nonunions are usually treated by enhancing stability of fixation, while atrophic nonunions require additional biological stimulation to achieve bone union. The Reamer-Irrigator-Aspirator (RIA) System® was developed to reduce intramedullary pressure and heat generation during intramedullary reaming, thus preventing thermal necrosis and decreasing the risk of fat embolism. The RIA System allows to provide large volumes of high-quality morselized autologous bone, that has shown high osteogenetic and osteoinductive properties. Therefore, its use has been expanded as a valuable source of autologous bone graft for the treatment of large bone defects of different nature. In this article, we present two cases of complex femoral nonunions treated with the use of the RIA System. A review of the published literature on the treatment of femoral nonunions with RIA was also performed. Core tip: In case of atrophic nonunions, the RIA System can be used to obtain biologically active tissue to enhance bone healing. Despite the absence of high-quality studies focused on femoral nonunions, the efficacy of RIA is well-known and orthopaedic surgeons should be aware of this powerful tool.
Keywords: aseptic nonunion; autologous bone graft; fracture nonunion; reamer-irrigator-aspirator; ria system.