Bma Illustrated Medical Dictionary

common in sports. Repeated strenuous

exercise may sprain the muscles (see

overuse injury).

handThe hand is made up of the wrist,

palm, and fingers. Movement of the hand

is achieved mainly by tendonsthat attach

the muscles of the forearm to the bones

of the hand (the carpals, metacarpals,

and phalanges) or by short muscles in

the palm of the hand.

The hands are highly susceptible to

injury. Dermatitisis also common. The

hand may be affected by Dupuytren’s

contractureor Volkmann’s contracture.

Degeneration of a tendon sheath on the

upper side of the wrist may cause a

harmless swelling called a ganglion.

Osteoarthritis commonly affects the joint

at the base of the thumb. Rheumatoid

arthritismay cause deformity.

hand–arm vibration syndromePain

and numbness in the handand arm due

to prolonged use of vibrating tools.

Symptoms often also include blue or

white coloration of the fingers and a

tingling sensation in affected areas.

Hand–arm vibration syndrome tends to

develop slowly over years and is the

result of repeated damage to blood ves-

sels and nerves. Exposure to cold tends

to aggravate the condition. There is no

specific treatment, but avoiding vibrat-

ing tools is essential to prevent the

disease progressing. In some cases,

calcium channel blockers may help

relieve some symptoms.

HAND

as a result of osteoarthritis. The joint is
usually tender and swollen. Treatment
of hallux rigidus comprises resting the
toe and wearing a support insert in
the shoe. Surgery may be required.
hallux valgusA deformity of the big toe
in which the joint at the base projects
out from the foot, and the top of the toe
turns inwards. The condition is more
common in women, because it is usually
associated with wearing narrow, pointed,
high-heeled shoes, but it may be caused
by an inherited weakness in the joint. A
hallux valgus often leads to formation
of a bunion or to osteoarthritisin the
joint, causing pain and limiting foot
movement. Severe deformity may be cor-
rected by osteotomyor arthrodesis.
haloperidolAn antipsychotic drugused
to treat mental illnesses such as schizo-
phreniaand mania. Haloperidol is also
given to control symptoms of Gilles de
la Tourette’s syndromeand, in small
doses, to sedate people who are aggres-
sive as a result of dementia. Side effects
include drowsiness, lethargy, weight
gain, dizziness, and parkinsonism.
halothaneA colourless liquid inhaled as
a vapour to induce and maintain general
anaesthesia (see anaesthesia, general).
hamartomaA noncancerous mass, re-
sembling a tumour, which consists of
an overgrowth of tissues that are nor-
mally found in the affected part of the
body. Hamartomas are common in the
skin (the most common is a haeman-
gioma), but they also occur in the lungs,
heart, or kidneys.
hammer-toeA deformity of the toe
(usually the second toe) in which the
main joint stays bent due to a tendon
abnormality. A painful cornoften devel-
ops on this joint. A protective pad can
ease pressure on the joint and relieve
pain, but surgery may be needed if the
pain is persistent.
hamstring musclesA group of muscles
at the back of the thigh. The upper ends
of the hamstring muscles are attached
by tendonsto the pelvis; the lower ends
are attached by tendons called ham-
strings to the tibia and fibula. The
hamstring muscles bend the knee and
swing the leg backwards from the thigh.
Tearing of the hamstring muscles is

HALLUX VALGUS HAND–ARM VIBRATION SYNDROME

H

Carpals

Metacarpals

Phalanges

BONES OF THE HAND