Bendy Backbone - Human Body Encyclopedia Series

Your spine is a length of bones running down the back of your body. Without it you couldn’t hold up your head and body, or make any sort of movement. The amount of movement between  each vertebra and its neighbours is actually very small, but added together they allow for a large range of movement.

Stack of bones

Your spine contains 24 separate bones called vertebrae. At the bottom are nine more vertebrae. They are much smaller and are fused together.
The first seven bones are in your neck. They are known as the cervical vertebrae.

The next 12 are called the thoracic vertebrae. The five lumbar vertebrae bear most of your weight. The five sacral vertebrae are fused together. The coccyx consists of four fused vertebrae.

The thoracic vertebrae form joints with the ribs. A straight back is actually quite curvy.

The fused bones of the sacrum and coccyx don’t allow much movement.

Segments of the spine

Each vertebra has a strong, stubby section that supports the weight of your body, and a hole for the spinal cord to pass through.

 

Shock absorbers

You twist and bend your spine almost every time you move. Sandwiched between the vertebrae are pads of cartilage to stop them banging and rubbing against each other and getting worn out.

 

Ribcage

Your thoracic vertebrae connect to your ribs. Together they form a cage around your heart and lungs. Rib bones are curved. They are  also thinner and more bendy than the bones in your spine.

Pelvis

Reproductive organs and some digestive organs rest in the bowl-shaped hollow of your pelvis. The sacral vertebrae and coccyx form the bottom of the bowl. A woman’s pelvis is shaped differently to a man’s. A baby can pass through it when she gives birth.