Einfluss der Granulatgröße des Knochenersatzmaterials Herafill und der 'bone marrow mononuclear cells' auf die Knochendefektheilung unter Verwendung der induzierten Membrantechnik nach Masquelet in vivo

Human bone has a great ability to repair and regenerate following injuries or surgeries. Bone healing involves a complex interaction of cells, growth factors, cytokines and the extracellular matrix (Hoerth et al., 2014). Nonetheless, bone fracture dramatically changes the mechanical stability of the bone. The distance between the two fracture ends plays a crucial role in bone healing. Here a distinction is made between the primary, the osteonal bone healing and the secondary, the callus-forming bone healing. The larger the fracture gap, the greater is the instability, the healing delay and thus the danger of a pseudarthrosis (Hoerth et al., 2014, Marsell et Einhorn, 2011). Large diaphyseal defects are usually caused by trauma, infection or tumor. They are referred to as a critical size defect (CSD) when surgical intervention is needed to induce the healing process (Rosset et al., 2014). Long bone defects still represent a major challenge in reconstructive surgery. Therefore research and development of implantable biomedical materials is an important task in the treatment of CSD. Currently the most common treatment for large diaphyseal defects is Autologous Spongiosaplasty (ASP) and it is the gold standard of therapy. However, the autologous bone materials are limited and cause many comorbidities. In addition there are allogeneic, xenogeneic and synthetic bone grafts. Nevertheless, none of the treatment options is so advanced that the ASP could be replaced. The allogeneic and xenogenic materials are unlimited in quantity, but have lower biocompatibility, higher risk of infection, and worse long-term efficacy results (Wang et al., 2014). Another disadvantage over the ASP is that the synthetic bone replacement materials have no osteoinductive and osteogenic properties. One way to obtain all the required qualities is to combine them with cell suspensions, such as bone marrow mononuclear cells (BMC) and thus try to develop a mature therapy concept. Moreover Masquelet et al. (2000) describes a new technique, a ...