The fluid phase of morsellized bone: Characterization of viscosity and chemical composition

Morsellized bone is widely used in orthopaedics to fill skeletal defects. The material behaviour is highly time-dependent, due to the liquid consisting of fat and water present in the impacted graft layer. In this study this fluid was characterized with respect to viscosity and chemical composition. Bovine bone was ground in a bone mill, transferred to tubes and centrifuged. This procedure allowed to successfully extract the fluid present inside the ground bone. The fluid was found to have similar composition to yellow bone marrow and a temperature dependent viscosity that could be described by Andrade’s equation with coefficients A=1.3×10−4Pas and B=3950∘C. The viscosity data can be used in quantitative modelling based on a mixture theory approach to simulate the mechanical behaviour of the graft during packing and cement filling in the femur.