Bone Type | Description | Purpose | Bones |
Long | Cylindrical, longer than they are wide. Composed mostly of compact bone with spongy bone at the ends. | Support body weight, facilitate movement, and act as levers for muscles. | Femur, tibia, fibula, humerus, radius, ulna, phalanges. |
Short | Cube-shaped, as long as they are wide. Mostly spongy bone with a thin layer of compact bone. | Provide stability and support while allowing some motion. | Carpals (wrist bones), tarsals (ankle bones). |
Flat | Thin, flattened, and often curved. Composed of two layers of compact bone with a layer of spongy bone in between. | Protect internal organs and provide large surface areas for muscle attachment. | Skull bones (frontal, parietal), sternum, ribs, scapula. |
Irregular | Complex shapes that don’t fit into other categories. | Protect organs and support multiple functions like movement. | Vertebrae, sacrum, mandible, pelvis. |
Sesamoid | Small, round bones embedded in tendons. Usually found near joints. | Reduce friction, act as pulleys for tendons, and protect tendons from stress. | Patella (kneecap), small sesamoid bones in the hands and feet. |