The whole body
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MusclesHow many bones are in the hand?
Each hand has 27 bones: 8 very small ones in the wrist, 5 in the palm and 14 in the fingers. Having so many little bones is what lets the hand make delicate movements, like holding a pencil or picking up a pebble.
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Questions people ask
Why is the thumb so important?
Because it can swivel and touch the tip of every other finger. This movement, called opposition, is what lets us pinch, hold small objects and use tools.
Do fingers have muscles?
Hardly any. The muscles that bend and straighten the fingers are in the forearm and palm, and pull the finger bones through tendons. Wiggle your fingers and watch your forearm: you can see the muscles working.
Which wrist bone breaks most often?
The scaphoid, on the thumb side. It usually breaks when someone falls onto an open hand. Pain at the base of the thumb after a fall should be checked by a doctor.
Why do knuckles crack?
Between the bones there is a fluid that lubricates the joints. When the joint is stretched, a gas bubble forms in that fluid, and that makes the sound. Studies have not shown that cracking knuckles causes arthritis.
Sources
This text was written using these references:
- Skeletal System · National Cancer Institute (SEER Training)
This content has not been medically reviewed.