Fourteen small long bones in each hand, two in the thumb and three in each of the other digits
Phalanges — the finger bones.
Anatomy · Bones
Phalanges
The finger and toe bones
Hand and foot · digits
The phalanges are the bones of the fingers and toes. There are 14 in each hand and 14 in each foot, 56 in the whole body: the thumb and the big toe have two each (proximal and distal), and every other digit has three (proximal, middle and distal). The name is from the ancient Greek phalanx, a tight block of soldiers.
How to spot them
- ▸Small long bones in a row in each finger and toe: proximal, middle and distal
- ▸Thumb and big toe have only two phalanges; the other eight digits have three
- ▸Each has a base, shaft and head; the head is pulley-shaped for the hinge-like interphalangeal joint
- ▸The distal phalanx of each finger ends in a flattened tuft supporting the pad and nail bed
What to know
Their name comes from an ancient Greek battle formation, a tightly packed rectangular block of soldiers
Phalanges — from the Greek phalanx (singular phalanx).
Fifty-six of the 206 bones in the body, more than a quarter of the skeleton
Phalanges — 14 in each hand and 14 in each foot.
Each has a base, a shaft and a pulley-shaped head, and adjacent ones meet at hinge joints that flex and extend only
Phalanges — the interphalangeal joints.
A ball hitting the tip of the finger can avulse the extensor tendon from the base of the last one, leaving the fingertip drooping in 'mallet finger'
Phalanges — the distal phalanx.
The only digits with two of these bones are the thumb and the big toe
Phalanges — the pollex and the hallux have proximal and distal phalanges only.
Rounding of the fingertips with swelling of the ends of the digits, 'clubbing', involves the terminal ones
Phalanges — the distal phalanges.
Key ideas
- Because the thumb has only two phalanges but a mobile first metacarpal, it works as a two-jointed lever on a mobile base; the other fingers are three-jointed levers on a fixed base.
- Each finger has a proximal (PIP) and a distal (DIP) interphalangeal joint; the thumb has a single interphalangeal joint.
Quick-fire facts
- •There are 14 phalanges in each hand and 14 in each foot: 56 in the body.
- •The thumb (pollex) and big toe (hallux) each have two phalanges; digits 2 to 5 each have three.
- •Phalanx (plural phalanges) is Greek for a battle line or block of soldiers, in reference to the rows of bones.
- •The distal phalanges of the lesser toes are among the smallest bones of the body after the ear ossicles; the smallest of all is the stapes of the middle ear.
- •Mallet finger is an avulsion of the extensor tendon at the distal phalanx; jersey finger is rupture of the flexor digitorum profundus tendon from the same bone, classically in rugby tackling.
- •Each finger is made of a proximal, middle and distal phalanx; the joints between them are the proximal and distal interphalangeal joints.
- •The metacarpophalangeal joints are the knuckles; the interphalangeal joints are hinges.
- •The phalanges of the toes are much shorter than those of the fingers, apart from the big toe's.
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