Phalanx bones
From Wikipedia, the free encyclopedia
The name Phalanx (plural phalanges) is commonly given to the bones that form fingers and toes. In primates such as humans and monkeys, the thumb and big toe have two phalanges, while the other fingers and toes consist of three. Phalanges are classified as long bones.
The phalanges do not really have individual names but are named after the digit, and their distance from the body.
- Distal phalanges are at the tips of the fingers and toes.
- Proximal phalanges are closest to the hand (or foot) and articulate with the metacarpals of the hand, or metatarsals of the foot.
- Middle or Intermediate phalanges are between the distal and proximal. The thumb and big toe do not have middle phalanges.
The term phalanx or phalanges refers to an ancient Greek army formation in which soldiers stand side by side, several rows deep, like an arrangement of fingers or toes.
The number of phalanges in animals is often expressed as a phalangeal formula, that indicates the numbers of phalanges in digits (beginning from medial), e.g. human has the formula 3-3-3-3-2, a deer has the formula 3-3 and most lizards have the formula 2-3-4-5-4.
