Acute minimally invasive bone grafting of long bone fractures to reduce the incidence of fracture non-union

Abstract

Diaphyseal fractures of the femur and tibia are a frequent consequence of trauma and are most often managed with intramedullary nailing. Although outcomes from these fractures are generally perceived as good, it is estimated that 7 to 14% of people with tibial and femoral shaft fractures progress to non-union and an even greater proportion suffer delayed union, which causes substantial health and economic burdens both for patients and health services. Compared to those whose fractures unite within the normal timeframe, patients suffering delayed union or non-union suffer more pain, worse functional outcomes, greater psychological disability and longer amounts of time off work. In response to non-union, invasive and costly secondary procedures such as exchange nailing, supplementary fixation and/or bone grafting are commonly required. We hypothesise that performing acute autologous bone grafting at the time of the primary intramedullary nailing procedure would reduce the incidence of fracture delayed union and non-union for tibial and femoral shaft fractures. The autologous cancellous bone retrieved during reaming with intramedullary nailing is usually discarded. We propose a minimally invasive surgical technique to transplant the retrieved intramedullary reamings to the fracture site during the primary fracture fixation. Autologous cancellous bone grafting is the gold standard for management of fracture non-union, and works by providing osteoprogenitor cells, an osteoconductive scaffold, and growth factors to the fracture site, where they are crucial for fracture healing. Proprietary biological products have also been developed that aim to replicate the results from bone grafting. Although autologous cancellous bone grafting is a proven and robust technique for the treatment of atrophic fracture non-union, it has not been widely studied in the acute management of femoral and tibial shaft fractures. The proposed hypothesis is amenable to testing in randomized clinical trials. If found to be effective in reducing rates of delayed union and non-union with minimal adverse events, this method could be adopted on a large scale, potentially transforming acute management of long bone fractures, and improving patient outcomes from these injuries.