What is the structure of a typical bone?

The two main types of bone are compact bone and trabecular bone.

• Compact (cortical) bone - this is bone which makes up the shafts of long bones (such as the femur or humours). The bone material is laid down in parallel sheets, providing great mechanical strength. It has a relatively greater proportion of the strong inorganic part of bone (80-90%).
• Trabecular (cancellous) bone - this is the bone which takes the form more of a scaffold structure, with 'struts' of bone formed in the planes of most stress with space between them. This gives such bones a degree of stress whilst making the bone very light. Such bone is found at the ends of the long bones (such as the head of the femur) and in light bones such as the vertebrae and parts of the pelvis. It has less inorganic matrix (13-25%).