(hand )

The body part attached to the forearm at the wrist. It includes the wrist (carpus) with its eight bones, the metacarpus or body of the hand (ossa metacarpalia) having five bones, and the fingers (phalanges) with their 14 bones. In some occupations and recreational endeavors, workers use their hand s as hammers, which may damage the ulnar nerve and artery, with consequent signs of ischemia and neuropathy. SYN: manus.

SEE: illus.

anarchic h.Alien limb phenomenon.

ape h.A deformity of the hand in which the thumb is permanently extended, usually caused by a median nerve injury. Paralysis and atrophy of the thenar muscles result.

benediction h.A deformity of the hand in which there is flexion of some of the fingers, especially of the terminal phalanges. The hand at the wrist may be extended. The condition may be caused by paralysis of the ulnar and median nerves.

claw h.

SEE: clawhand .

cleft h.A bipartite hand resulting from failure of a digit and its corresponding metacarpal to develop. SYN: lobster-claw hand ; split hand .

diabetic h.A deformity of the hand marked by stiffness and fibrotic contractures of the metacarpophalangeal and proximal interphalangeal joints in patients with advanced diabetes mellitus.

dominant h.In American Sign Language, the hand that moves during the formation of a sign. SYN: preferred hand .

drop h.Wrist drop.

functional position of h.

SEE: under position.

helper h.In a two-hand ed task, the hand that stabilizes something so the dominant hand can perform a skilled procedure on it.

lobster-claw h.Cleft hand .

obstetrician's h.A deformity of the hand in tetany, marked by extension at the metacarpophalangeal and the interphalangeal joints and adduction of the thumb. It is named for the position of the obstetrician's hand during vaginal examination.

opera-glass h.A deformity of the hand caused by chronic arthritis in which the phalanges appear to be telescoped into one another like an opera glass.

preferred h.Dominant hand .

split h.Cleft hand .

worker h.In a two-hand ed task, the hand that performs the skilled procedure. Also known as the dominant hand .

writing h.A deformity of the hand in which the tips of the thumb and first finger are touching and the other fingers are flexed as if holding a writing instrument. This is seen in Parkinson disease.

illus.