Editorial: Biofabrication and Biopolymeric Materials Innovation for Musculoskeletal Tissue Engineering cook

The human musculoskeletal system provides form, support, stability, and movement to the body. It is made up of the bones of the skeleton, muscles, cartilage, tendons, ligaments, joints, and other connective tissues. The primary functions of the musculoskeletal system include supporting the body, allowing motion, and protecting vital organs. The skeletal portion of the system serves as the main storage system for calcium and phosphorus and contains critical components of the hematopoietic system (Li and Niu, 2020). Musculoskeletal Disorders (MSDs) include injuries and diseases that primarily affect the movement of the human body. They are characterized by pain and limitations in mobility, dexterity, and overall level of functioning, reducing patients’ ability to work and maintain a good quality of life. A recent analysis of Global Burden of Disease data showed that approximately 1.71 billion people globally have musculoskeletal conditions (Woolf and Pfleger, 2003). MSDs such as osteoarthritis, rheumatoid arthritis, psoriatic arthritis, gout, and ankylosing spondylitis affect joints (McInnes and Schett, 2011; Loeser et al., 2012; Litwic et al., 2013); osteoporosis, osteopenia and associated fragility fractures, as well as traumatic fractures, affect bones (Florencio-Silva et al., 2015); sarcopenia affects muscles, and back and neck pain affect the spine of the human body

Parametric Design of Femoral Implant with Gradient Porous Structure

Patients who has been implanted with hip implant usually undergo revision surgery. The reason is that high stiff implants would cause non-physiological distribution loadings, which is also known as stress shielding, and finally lead to bone loss and aseptic loosening. Titanium implants are widely used in human bone tissues; however, the subsequent elastic modulus mismatch problem has become increasingly serious, and can lead to stress-shielding effects. This study aimed to develop a parametric design methodology of porous titanium alloy hip implant with gradient elastic modulus, and mitigate the stress-shielding effect. Four independent adjustable dimensions of the porous structure were parametrically designed, and the Kriging algorithm was used to establish the mapping relationship between the four adjustable dimensions and the porosity, surface-to-volume ratio, and elastic modulus. Moreover, the equivalent stress on the surface of the femur was optimized by response surface methodology, and the optimal gradient elastic modulus of the implant was obtained. Finally, through the Kriging approximation model and optimization results of the finite element method, the dimensions of each segment of the porous structure that could effectively mitigate the stress-shielding effect were determined. Experimental results demonstrated that the parameterized design method of the porous implant with gradient elastic modulus proposed in this study increased the strain value on the femoral surface by 17.1% on average. Consequently, the stress-shielding effect of the femoral tissue induced by the titanium alloy implant was effectively mitigated