Compact vs Cancellous Bone | Cortical vs Cancellous Bone
No, do not think that compact and Cancellous are different types of bones (there are 206 different bones in our body). Rather they refer to different types of tissues found in a bone that are called as compact (or cortical) and Cancellous (or spongy) because of their physical properties. Not many people are aware of the differences between compact and cancellous bone tissues and what functions are served by them.
There are mainly two types of tissues found inside our bones namely compact and cancellous. The major difference between these bone tissues lies in the their density. The part of the bone where these tissues are densely packed is called compact bone and the part where they are loosely packed is called cancellous bone.
Compact bone or cortical bone is the outer shaft of the bone. This is where the tissues are closely packed together giving a smooth and white appearance to the bone. This part takes up nearly ¾ of the bone. There are cavities inside compact bones where bone marrow is stored. Compact bone is thus primarily the outer surface of the bone. It is also the shafts in long bones. It is extremely hard bone with very few gaps inside and the connective tissues being densely packed.
Cancellous or spongy bone tissues make up for most of the matter inside a bone. Here, tissues are less densely packed giving it the appearance of a sponge (thus the name). Though it is softer than compact bone, it is really not spongy as the name suggests. It protects internal organs and this is where blood is produced inside the body. It is also a store house for minerals. Red and white blood cells are manufactured here.
Compact vs Cancellous Bone
• Bones are not universally hard as against common misconception. Even the outer part or the surface of the bone has some holes in it. This part is known as compact bone and is a place where bone marrow is kept by body inside cavities
• The interior part of the bones contains tissues that are softer and less densely packed. This part of the bone is called cancellous bone. Also called spongy (though it is still hard), it contains red marrow. This is where red and white blood cells are manufactured and minerals are stored by the body. Cancellous bones protect internal organs of the body.