Manus (anatomy)

Manus (anatomy)

The Manus is the zoological term for the distal portion of the forelimb of an animal. In humans, it is referred to as the hand, including the wrist, palm, thumb, and fingers. The manus contains 27 bones, divided into three groups: the carpus, metacarpus, and phalanges.

Structure

Carpus

The carpus or wrist is made up of eight carpal bones, which are arranged in two rows. The proximal row is, from lateral to medial: scaphoid, lunate, triquetral and pisiform. The distal row is, from lateral to medial: trapezium, trapezoid, capitate and hamate.

Metacarpus

The metacarpus is made up of five metacarpal bones, which are numbered from medial to lateral. Each metacarpal consists of a base, a shaft, and a head.

Phalanges

The phalanges are the bones of the fingers. Each finger (except the thumb) has three phalanges: a proximal, a middle, and a distal phalanx. The thumb only has a proximal and a distal phalanx.

Function

The manus is capable of a wide variety of functions due to its complex structure and the flexibility of its joints. These functions include fine motor skills like grasping and manipulating objects, as well as gross motor skills like waving and punching.

Clinical significance

Injuries and diseases of the manus are common and can have significant impacts on quality of life. These include carpal tunnel syndrome, fractures, arthritis, and tendonitis.

See also

• Pediculus
• Digit
• Limb