This review paper aims to provide a comprehensive overview of the current state of the art on injectable polymers for trabecular bone repair, highlighting their properties, advantages, and applications. It will also discuss the challenges and future directions in the development of these Figure Cell types found within bone tissue . Reproduced with permission from OpenStax.org Bone has a hierarchical structure and can be viewed as a natural composite material containing organic and inorganic phases, where water accounts for around 25% of the mass of the bone. At a nanoscale level it is composed mainly of type I collagen fibers which account for about 90% of bone's organic matter; collagen is a protein which is responsible for bone's ductility and absorbing energy. Collagen fibers/molecules are tightly packed with a consistent gap of approximately 35 nm between them, which facilitates the formation of crystallization nuclei. The inorganic component of the composite are small hydroxyapatite (HA) crystals, which account for about 65% of dry bone weight and provide the stiffness and structural strength. Mineral crystals have a plate shape and align with the longitudinal direction of collagen fibers (Figure ). These plate shaped crystals vary in thickness from 2 to 7 nm, width from 10 to 80 nm, and length from 15 to 200 nm. This arrangement is responsible for the anisotropic properties (varying, depending on the direction of measurement) of bone such as higher values of stiffness and strength in that direction. Further up the structural hierarchy, these mineralized collagen fibrils (measuring 0.5 -1 μm) organize parallel to each other to form larger fibers. Depending on the bone's developmental stage and its mechanical requirements, these fibers can be arranged in a lamellar (layered) or woven pattern. Woven bone, which appears in the early stages of bone formation, has a less organized structure and is typically replaced by the more structured lamellar bone as the bone matures .