Trabeculae are the fundamental structural units that make up trabecular bone, also known as spongy bone. These are small, rod-like or plate-like structures that form an irregular, lattice-like network, creating a honeycomb-like pattern within the bone.
Trabeculae form a three-dimensional network that provides structural support while reducing the overall weight of the bone. Unlike compact bone, which is dense and solid, trabecular bone has spaces between the trabeculae that are filled with bone marrow. This arrangement creates an efficient structure that maximizes strength while minimizing weight.
Trabeculae serve several critical functions in bone structure. They distribute mechanical stress throughout the bone, minimize overall bone weight while maintaining strength, maximize surface area for cellular activity, and provide support for bone marrow. This design creates an optimal balance between structural strength and weight efficiency, making bones both strong and lightweight.
Trabecular bone and compact bone have distinct characteristics. Trabecular bone makes up only twenty percent of the skeleton's mass but provides eighty percent of the bone surface area, leading to higher metabolic activity. It has a porous structure with spaces between trabeculae. In contrast, compact bone comprises eighty percent of skeletal mass but only twenty percent of surface area, with lower metabolic activity and a dense, solid structure.