Dolph Houben

57 Combined massive allograft and intramedullary vascularized fibula 3 Introduction Segmental bone loss is a serious and challenging problem after limb saving oncological surgery, severe complex trauma, and infection [1] . Methods used to restore segmental bone loss include vascularized autogenous bone, the Masquelet technique, distraction osteogeneses, prosthetic replacement, re-implantation of autoclaved tumor bone and massive allografts used alone or in combination with a vascularized autograft [2-5] . The Masquelet technique [6] is a commonly used and well-known technique in trauma. This technique uses a combination of unvascularised autologous bone graft and an induced membrane in a specific time frame. The downside of this two-stage reconstruction method is the long time it takes before full weight bearing is allowed and its association with infection, resorption, and non-union [7] . Distraction osteogenesis is also commonly used in trauma cases but is associated with pin-tract infection, soft tissue problems, non-union at the docking site, and prolonged non-weight bearing [8, 9] . Prosthetic replacement is associated with failure rates ranging from 33% to 100%, requiring revision or amputation for mechanical failure and/or infection [10-12] . Massive allografts alone or re-implementation of autoclaved tumor bone are both relatively simple reconstruction methods. They provide a “like with like” tissue reconstruction with immediate strength and no donor site morbidity. However, these non-vascularized bone grafts have many disadvantages and are associated with complications as non-union, infection and graft fractures. This is thought to be due to the avascular status of the graft [7, 13-19] . The vascularized fibula flap provides a good option for the reconstruction of large segmental defects. Vascularized bone grafts contain an intrinsic blood flow, provide osteogenic factors to the reconstruction and are capable of osteogeneses. These factors result in faster union times, improved strength and healing [20] . The downside of the use of a free or pedicled vascularized fibula flap is the risk of flap failure and the need for a donor site with its associated morbidity. In addition, there is a possible mismatch in size and strength between the original bone and the fibular graft, due to a smaller diameter of the fibula. This mismatch may necessitate a long period of non-weight bearing and can lead to fractures of the fibular graft. A combination of a vascularized fibular graft with a massive allograft provides the benefits of both methods and is also known as the Capanna technique [21] . Immediate strength and bulk provided by the massive allograft and the potentials of a vascularized fibular graft for primary union, hypertrophy and resistance to infection [7, 13, 15-19, 22-30] . Current literature on the outcome of the Capanna technique is limited by mostly retrospective studies with small sample size and conflicting results. In order to better understand the existing data, there is a significant necessity to further evaluate this data. This systematic review focuses on union rate, complication rate, re-intervention rate, time to full weight bearing, and functional outcome after reconstruction with massive allograft combined with vascularized fibular inlay.