Where the first metacarpal bone sits in the skeleton
The first metacarpal bone is the 1st of the five metacarpals of the palm, in line with the thumb. It joins the wrist bones at its base and the thumb's proximal phalanx at its head. Shorter and thicker than the others and more mobile, it lets the thumb meet the other fingers. Its base forms a saddle-shaped carpometacarpal joint with the trapezium.
Frequently asked questions
Which part of the skeleton is the first metacarpal bone in?
The first metacarpal bone is one of the bones of the hand. The hand is made of eight carpal bones, five metacarpals and fourteen phalanges.
How many bones are in the hand?
Each hand has 27 bones: eight carpal bones in the wrist, five metacarpals in the palm and fourteen phalanges in the fingers.
Is there one first metacarpal bone or a pair?
The first metacarpal bone is paired: there is one on the left and one on the right, and this page covers both.
Which wrist bone does the first metacarpal meet?
The trapezium. This saddle joint is what lets the thumb turn to meet the other fingers.
Other bones of the hand
- Scaphoid
- Lunate
- Triquetral
- Pisiform
- Trapezium
- Trapezoid
- Capitate
- Hamate
- Second metacarpal bone
- Third metacarpal bone
- Fourth metacarpal bone
- Fifth metacarpal bone
- Proximal phalanx of thumb
- Distal phalanx of thumb
- Proximal phalanx of index finger
- Middle phalanx of index finger
- Distal phalanx of index finger
- Proximal phalanx of middle finger
- Middle phalanx of middle finger
- Distal phalanx of middle finger
- Proximal phalanx of ring finger
- Middle phalanx of ring finger
- Distal phalanx of ring finger
- Proximal phalanx of little finger
- Middle phalanx of little finger
- Distal phalanx of little finger
Joints of the first metacarpal bone
Compare with similar bones
Bone counts
By region
Read more
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