Why is the Rib Cage So Important?

Labeled rib cage anatomy diagram with numbers

The rib cage is like a safety shield for your chest! It’s your body’s natural protection around your lungs and heart. Give yourself a hug around your chest, and you can feel many hard rib bones. In the mirror, you might be able to see the outline of some of your ribs.

What is the Rib Cage Made of?

Like most parts of the human skeleton, the rib cage is made of both bone and cartilage.

What are the Parts of the Rib Cage?

Sternum (Breastbone)

The sternum is in the front and middle part of the rib cage. This bone is long, vertical and flat and gives the heart extra protection. Since it is located between the breasts, the sternum is also called the breastbone.

12 Pairs of Ribs

  • Most people have 12 pairs of ribs, which are flat, curved bones. When doctors talk about the rib bones, they give each rib a number from 1 through 12.
    • The first 7 ribs are attached to the sternum with the help of their own cartilage. These are ribs number 1, 2, 3, 4, 5, 6, and 7.
    • The next 3 ribs are attached to the sternum with the help rib number 7’s cartilage. These are ribs number 8, 9, and 10.
    • Ribs number 11 and 12 are considered “floating ribs”, because they are not attached to the sternum. This allows humans to bend forward at the waist.
  • All ribs are connected to the vertebrae (backbone).

Watch This Video for a Peek at the Rib Cage Bones!

What Are the Soft Spaces Between the Ribs?

If you run your hands up and down your sides, you can feel soft grooves in between each rib. These spaces are filled with many important organs:

  • BLOOD VESSELS: Tucked under every rib bone are bundles of veins and arteries. The veins that take away waste and the arteries bring important nutrients to the rib cage.
  • NERVES: Nerves are lined up like wires under each vein and artery. The brain sends messages through those nerves to control your chest muscle movements.
  • MUSCLES: The muscles between each rib move your chest to help you breathe.

What Other Bones are Connected to the Rib Cage?

The clavicles (collarbone) are attached to the top of the sternum.


  • BREATHINGWhen you breathe in air, your lungs get bigger. When you breathe out air, your lungs get smaller. This means your rib cage has to get bigger and smaller, too.
  • PREGNANCY – When a fetus (baby) grows bigger in its mother’s uterus, everything in the belly is crowded. To make space for the baby, the uterus moves up toward the chest. Because of these changes, the rib cage becomes a little wider during pregnancy. Many pregnant women can also feel the fetus kicking their ribs during pregnancy. Ouch!

Updated on July 11, 2022 Reviewed by Betty Choi, MD

Updated on July 11, 2022

Reviewed by Betty Choi, MD