Metacarpus facts for kids

Bone: Metacarpals
The five metacarpal bones, numbered.
Multiple fractures of the metacarpals (aka broken hand).

The metacarpus is a group of five bones found in your hand. These bones are often called the "palm bones." They connect your wrist to your fingers. Each of your five fingers, including your thumb, has its own metacarpal bone.

These important bones help give your hand its shape and strength. They also allow you to move your fingers and thumb in many different ways.

What are Metacarpal Bones?

Your hand has five metacarpal bones. They are long bones, but not as long as the bones in your arm or leg. Each metacarpal bone has three main parts:

• A base, which connects to the bones of your wrist.
• A shaft, which is the long middle part.
• A head, which connects to the bones of your fingers.

The metacarpal bones are numbered from one to five. Metacarpal I is the bone for your thumb. Metacarpal V is the bone for your little finger.

Where are Metacarpals Found?

The metacarpal bones are located in the middle part of your hand. They are between the bones of your wrist, called the carpus, and the bones of your fingers, called the phalanges.

Imagine your hand:

• Your wrist is at the bottom.
• Your fingers are at the top.
• The metacarpals are the bones that make up the main part of your palm, connecting these two areas.

What Do Metacarpals Do?

Metacarpal bones are very important for how your hand works. They help you:

• Grip things: They provide a strong base for your fingers to grip objects.
• Move your fingers: Muscles and tendons attach to these bones, allowing you to bend, straighten, and spread your fingers.
• Support your hand: They form the main structure of your palm, giving your hand its shape and strength.

Without healthy metacarpal bones, it would be hard to do everyday tasks like writing, holding a ball, or even waving hello!

Common Metacarpal Injuries

Because your hands are used so much, metacarpal bones can sometimes get injured.

• Fractures: A fracture means a broken bone. Metacarpal fractures can happen if you hit your hand hard, fall on it, or punch something. A common type is a "boxer's fracture," which is a break in the metacarpal bone of the little finger.
• Sprains: Ligaments, which connect bones, can get stretched or torn. This can happen around the joints where metacarpals meet other bones.

If you think you might have a metacarpal injury, it's important to see a doctor. They can take an X-ray to see if a bone is broken and help you get the right treatment.

Images for kids

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  Left hand shown with thumb on left.

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  The principle of homology illustrated by the different shapes of metacarpal bones in mammals. All mammals have similar hand bones, but they are changed to help animals do different things, like flying or swimming. The third metacarpal is shown in a darker color.

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  Carpometacarpal joints of the left hand. Thumb on left.

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  Carpometacarpal joints of the left hand. Thumb on left.

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  An X-ray image of a hand.

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  Metacarpus (yellow). Where muscles attach are shown in red. Left hand, front view.

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  Metacarpus (yellow). Where muscles attach are shown in red. Left hand, back view.

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  Metacarpus of the left hand (shown in red). This is an animation.

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  An X-ray image of a right hand with the thumb on the left.

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  Many broken metacarpal bones (also called a broken hand). (Right hand shown with thumb on left.)

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  An X-ray image of a baby's left hand.

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  A micro-radiography image of an 8-week-old human embryo's hand.

See also

In Spanish: Metacarpo para niños