Stable mechanical fixation in a bionic osteochondral scaffold considering bone growth

In the field of tissue engineering, there is significant subsidence of the porous design scaffold several months after implantation. To avoid stress shielding and stimulate bone and cartilage ingrowth, high scaffold porosity is needed to diminish the mechanical properties of the scaffold. The closer the mechanical properties of the scaffold are to those of surrounding tissues, the better biological properties it will get. Besides, adequate mechanical stability is needed as the scaffold needs to be well fixed in the target area and it will endure load after surgery. Evaluating the mechanical fixation of the scaffold at the initial stage and the long-term performance of a scaffold for in vivo study is hard, as no facility can be put into the target area for the friction test. This study investigated the mechanical stability of the biomimetic scaffold at the initial stage of implantation by finite element analysis (FEA). According to in vivo study, scaffold could not maintain its original position and would sink 1–2 mm in the target area. The simulation results suggested that mechanical loading is not the main reason for scaffold subsidence.