Abstract: According to the analysis on porous structure of human bone and factors influencing scaffold performance, the generation and evaluation method of porous structure of bionic bone scaffold is proposed. Based on the structure of multi-constrained knapsack problem model and an ellipsoid taken as the unit body, the hybrid genetic algorithm is used to solve the inverse model of porous structure. Moreover, porosity and connectivity are used as the constraint condition to ensure the bioactivity of bionic bone scaffold. The model of bionic bone scaffold with pores is generated by Boolean operation between the model of scaffold without pores and the inverse model of porous structure. The evaluation system of porous structure of bionic bone scaffold is established with five evaluation indexes, i.e. porosity of scaffold, connectivity of pore, uniformity of pore distribution, twisting degree of pore canal and specific surface area of scaffold. Based on the inverse model of porous structure of scaffold, the calculation methods of porosity, connectivity, uniformity, twisting degree and specific surface area of scaffold are proposed to evaluate and optimize the porous structure of bionic bone scaffold. The bionic bone scaffold generated with this method has good bioactivity, better mechanical properties and uniform degradation rate.

Key words: Bionic bone scaffold, Connectivity, Knapsack problem model, Porosity, Porous structure