views updated May 29 2018

wrist The joint between the end of the forearm and the hand. Confusion can arise because a ‘wrist’ watch is actually worn above the wrist (it would be both inconvenient and uncomfortable to wear a watch over the joint itself). Movements occur in two planes — flexion/extension and adduction/abduction (inward/outward). This is a relatively complex joint as it is an articulation between the lower end of the long bones of the forearm (radius and ulna) and the eight small bones of the hand (carpal bones). These carpal bones are connected to one another by ligaments so that they form an arch, concave towards the palm, with its ends connected by a fibrous tissue band. Through this ‘tunnel’ run long tendons which control the fingers and, more importantly, the median nerve which carries the nerve supply to some muscles of the hand and to the skin of some of the fingers. This arrangement can present problems; the sheaths of the tendons can become inflamed and swollen thereby compressing the median nerve, leading to loss of sensation of the thumb, index, and middle fingers and loss of fine co-ordinated movements of the thumb (carpal tunnel syndrome). This can result from repetitive movements when using machinery, and the condition has become recognized as a form of industrial injury. Because of the reflex protective outstretching of the hand during a fall, the wrist is a common site of injury, often sprains. Fractures of the ends of the radius and ulna also occur (Colles fracture), particularly in elderly women with osteoporosis.

William R. Ferrell

See also hands; joints; skeleton.


views updated Jun 27 2018

wrist / rist/ • n. 1. the joint connecting the hand with the forearm.See also carpus. ∎  the equivalent joint (the carpal joint) in the foreleg of a quadruped or the wing of a bird. ∎  the part of a garment covering the wrist; a cuff.2. (also wrist pin) (in a machine) a stud projecting from a crank as an attachment for a connecting rod.


views updated Jun 11 2018

wrist OE., corr. to (M)LG. wrist, (M)HG. rist wrist, instep, withers, ON. rist instep:- Gmc. * wristiz, prob. f. * wrið-, f. wk. grade of the stem of WRITHE. Comp. wristband part of a sleeve that covers the wrist. XVI.
Hence wristlet XIX.


views updated May 21 2018

wrist (rist) n.
1. the joint between the forearm and hand. It consists of the proximal bones of the carpus, which articulate with the radius and ulna.

2. the whole region of the wrist joint, including the carpus and lower parts of the radius and ulna.