SINUSITIS
SKIN
lower forehead; 2 ethmoidal sinuses be-
tween the eyes; 2 maxillary sinuses in
the cheekbones; and the sphenoidal
sinuses in the skull behind the nose.
SKELETON
Parietal bone
Frontal bone
Mucus drains from each sinus along a
channel that opens into the nose. Infec-
tion of a sinus causes
sinusitis.
sinusitis Inflammation of the membrane
lining the facial
sinuses
caused by infec-
tion, usually spread from the nose. The
maxillary and the ethmoidal sinuses are
most commonly affected.
Sinusitis may cause a feeling of fullness
in the affected area, fever, a stuffy nose,
and loss of the sense of smell. A com-
mon complication is the formation of
pus in the affected sinuses, causing
pain and nasal discharge.
Treatment of sinusitis is is usually
with
antibiotics
and a
decongestant.
Steam inhalations
may also be helpful. If
sinusitis persists despite treatment,
surgical drainage of the affected sinuses
may be performed.
sinus tachycardia A fast, but regular,
heart-rate (more than 100 beats per
minute) caused by increased electrical
activity in the
sinoatrial node.
Such a
heartbeat is normal during sudden
stressful moments or exercise. Persis-
tent sinus tachycardia at rest may be
caused by fever or
hj/perthjrroidism.
situs inversus An unusual condition in
which the internal organs are situated
in the mirror image of their normal posi-
tions. No treatment is needed provided
all the organs are functioning normally.
Sjogren's syndrome A condition in
which the eyes and mouth are excessively
dry. The nasal cavity, throat, and vagina
may also be affected. The syndrome
tends to occur with certain
autoimmune
disorders
,
such as
rheumatoid arthritis
and systemic
lupus erythematosus
.
Most
sufferers are middle-aged women.
skeleton
The framework of bones that
gives the body shape and provides
attachment points for the muscles and
underlying soft tissues of the body. The
average human adult skeleton has 213
bones
(counting each of the 9 fused ver-
tebrae of the sacrum and coccyx as
individual bones) joined with
ligaments
and
tendons
at points called
joints.
The
skeleton plays an indispensable role in
Mandible
Scapula
Sternum
Humerus
Radius
Occipital bone
Zygomatic arch
Clavicle
Rib
Vertebral
column
Pubis
Ischium
Carpals
Metacarpals
Phalanges
Tarsals
Phalanges
movement by providing a strong, stable
but mobile framework on which mus-
cles can act. The skeleton also supports
and protects internal body organs.
skin
The outermost covering of body tis-
sue, which protects internal organs from
the environment. Skin has 2 layers: the
outer epidermis, and the inner dermis.
The outermost epidermis is composed
of dead cells and the protein
keratin
.
As
these dead cells are worn away, they are
replaced by new ones from the inner epi-
dermis. Some epidermal cells produce
the pigment
melanin
, which protects the
body from
ultraviolet light
in sunlight.
The dermis is composed of
connective
tissue
interspersed with
hair
follicles,
Ilium
S
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