Trabeculae refers to the network of spiny bone processes that make up the framework of spongy bone. Red or yellow marrow is located in the spaces between each trabecula. The type of marrow depends on the person's age and in which bone it is located.
Spongy bone is also known as cancellous bone. It comprises about 20 percent of the human skeletal system and provides structure and support. It is located in regions of the bone that are more likely to be stressed. Cancellous bone can turn into compact bone with cells known as osteoblasts. Osteoblasts deposit bone material around the trabeculae. When the spaces between the trabeculae are eliminated, a compact bone is formed.