What is the Difference Between Trabecular and Cortical Bone?

Trabecular and cortical bone are the two macroscopic forms of bone tissue in the human body. They have distinct structural and mechanical properties, which contribute to their unique functions.

Trabecular Bone:

• Also known as spongy or cancellous bone.
• Found in the inner parts of bones, surrounding the bone marrow.
• Highly porous (70-80%).
• High surface area, which facilitates bone cell production and mineral exchange.
• Has a larger remodeling area and higher metabolic activity compared to cortical bone.
• Transfers mechanical loads from the articular surface to the cortical bone.
• Hydraulic properties absorb shock.
• Plays a role in mineral homeostasis.

Cortical Bone:

• Also known as compact bone.
• Found on the outer layer of long bones and makes up about 80% of the skeleton.
• Stiff and able to resist higher ultimate stresses than trabecular bone, but also more brittle.
• Thin and strong, providing protection and bearing the weight of the body.
• Resistance to bending and torsion is higher than in trabecular bone.
• Low porosity and less metabolically active than trabecular bone.
• Plays a key role in providing strength and protection to bones.
• Microscopically identical to trabecular bone.

In summary, trabecular bone is characterized by its high porosity and metabolic activity, while cortical bone is dense, strong, and provides protection and support to the bone structure. Cortical bone is stiffer and more brittle than trabecular bone, which is more adaptable and can withstand higher strains. Both types of bone are essential for maintaining bone health and overall strength.

Comparative Table: Trabecular vs Cortical Bone

Trabecular and cortical bone are two different types of bone tissue in the human body. Here is a table highlighting the differences between them:

Trabecular bone is more porous and has a larger surface area than cortical bone, which is denser and has a lower porosity. These differences in structure and properties result in distinct roles for each type of bone tissue, such as mechanical strength for cortical bone and mineral homeostasis for trabecular bone.