Which skeletal sites are predominantly made up of cortical bone?

• A. Spine and Ward's Area
• B. Total body, femoral neck, and fingers
• C. Proximal forearm and distal forearm
• D. All options listed above

Answer: (D)

Cortical bone, also known as compact bone, is the dense outer surface of bone that forms a protective layer around the internal cavity. It is primarily found in areas that require more structural integrity and strength. When considering the skeletal sites mentioned:

• The spine consists of vertebrae, which contain a mix of both cortical and trabecular (spongy) bone. However, regions of interest within the vertebrae may still support some level of measurement in terms of cortical density.

• The femoral neck is particularly important in assessing hip fractures and osteoporosis as it provides a significant amount of weight-bearing support. It is predominantly composed of cortical bone, which contributes greatly to its load-bearing capabilities.

• The fingers, particularly the distal phalanges, have a significant cortical component, which is necessary for protection and support during gripping.

• The total body measurement encompasses various types of bones, including both cortical and trabecular structures and thus would not be exclusively cortical.

• The proximal and distal forearm regions largely represent areas with substantial cortical bone, given their role in weight-bearing and movement.

Since the question asks for skeletal sites predominantly made of cortical bone, the comprehensive inclusion of various sites in Option D reflects the correct understanding that all listed options