Cortical bone is the dense outer surface of bone that forms a protective layer around the internal cavity.

This type of bone also known as compact bone makes up nearly 80% of skeletal mass and is imperative to body structure and weight bearing because of its high resistance to bending and torsion.

Cortical bone in the spine, arms and legs can be damaged by trauma or bone disease such as osteoporosis. To treat weakened cortical bone, cortical bone grafting can be employed using synthetic bone material and other surgical implants including metal plates, screws and wires to reinforce weakened areas of the bone.