walking Movement of the body by lifting
the feet alternately and bringing
into contact with the ground before the
other starts to leave it. A person's gait is
determined by body shape, size, and
posture. The age at which children first
walk varies enormously.
Walking is controlled by nerve signals
from the brain's motor cortex (see
brum), basal ganglia,
travel via the spinal cord to the muscles.
Abnormal gait may be caused by joint
stiffness, muscle weakness (sometimes
due to conditions such as
or skeletal abnor-
malities (see, for example,
congenital dislocation of; scoliosis; bone
Children may develop
of the hip
are also common.
Adolescents may develop a painful limp
due to a slipped epiphysis (see
) or to fracture or dis-
ease of the
Abnormal gait may also be the result
of neurological disorders such as
(commonly resulting in
, various forms of
chorea. Meniere's disease
may cause sev-
ere loss of balance and instability.
walking aids Equipment for increasing
the mobility of people who have a dis-
order that affects their ability to
Aids include walking sticks, crutches,
and walking frames.
walking, delayed Most children walk
by around 15 months of age. Delayed
walking may be suspected if the child is
unable to walk unassisted by 18 months
treat and prevent abnormal
. Warfarin is used to treat
who are at
risk of an
It is also prescribed
to prevent emboli from developing on
replacement valves (see
gery). A faster-acting anticoagulant, such
, may also be prescribed for
the first few days following a deep-vein
thrombosis or pulmonary embolism.
Warfarin may cause abnormal bleeding
in different parts of the body, so regular
tests are carried out to allow careful
regulation of dosage. Warfarin may also
cause nausea, diarrhoea and a rash.
wart A common, contagious, harmless
growth that occurs on the skin or mucous
membranes. Only the topmost layer of
skin is affected. An overgrowth of cells
in this layer causes a visible lump to
develop. Warts are caused by the human
papillomavirus, of which at least 30 dif-
ferent types are known. These cause
different types of warts at various sites,
such as on the hands or genitals.
Raised surface of wart
Flat warts are flesh-coloured, sometimes
itchy lumps with flat tops that occur
mainly on the wrists, backs of hands, and
face. About 50 per cent of warts disap-
6 -1 2
months without treatment.
However, genital warts should be treated
promptly. Common, flat, and plantar
warts can sometimes be destroyed using
a wart-removing liquid or special plaster.
Several treatments may be necessary,
and sometimes the wart returns. Warts
are commonly treated by