ARTHRODESIS
A
(replacement of a joint with an artificial
substitute) or
arthrodesis
(fusion of the
bones in a joint).
arthrodesis
A surgical procedure in which the two
bones in a diseased joint are fused to
prevent the joint from moving, which
relieves pain in the affected area.
HOW AND WHY IT IS DONE
Arthrodesis is performed if a joint is
painful or unstable and other treat-
ments, such as drugs or
arthroplasty
(replacement of the joint with an arti-
ficial substitute), have failed or are
inappropriate.
Arthrodesis of a small joint, such as a
finger joint, may be carried out under
local anaesthetic (see
anaesthesia, local).
Otherwise, a general anaesthetic (see
anaesthesia, general
) is used. In most
cases, cartilage (smooth, shock-absorb-
ing tissue) is removed from the ends of
the two bones, along with a surface
layer of bone from each. The two ends
are then joined so that they will fuse
when fresh bone cells grow. The bones
may need to be kept in position with
plates, rods, or screws; a
bone graft
may
also be carried out in some cases.
In arthrodesis of the knee or ankle
joints, additional immobilization of the
joint (by transfixing it with pins inserted
through the skin) may be necessary to
keep the area stable until healing is
complete.
RECOVERY AND OUTLOOK
Complete union of the bones can take
up to six months but may be much
quicker. In some cases the bones fail to
fuse, but fibrous tissue usually fills the
gap between them and is strong enough
to provide the same effect and strength
as bone fusion.
Following arthrodesis, no movement
can take place in the affected joint,
unlike after arthroplasty. However, the
advantage
of arthrodesis
over
arth-
roplasty
is
that,
once
it
has
been
performed, it requires no regular sur-
veillance or further care; and the patient
can be reasonably confident that the
problem
with
the
joint
has
been
resolved permanently.
arthrography
A diagnostic technique in which the
interior of a damaged joint is X-rayed
following the injection of a radiopaque
(visible on
X-ray
) solution. The proce-
dure is gradually being replaced by
MRI
,
ultrasound scanning,
and
arthroscopy.
arthrogryposis
See
contracture.
arthropathy
A medical term for any disease or disor-
der that involves the
joints.
(See also
diabetic arthropathy.)
arthroplasty
Replacement of a joint or part of a joint
by metal or plastic components. A
hip
replacement
is one of the most common
operations of this type, as is a
knee-joint
replacement.
Replacement
of
other
joints, such as the finger (see
finger-joint
replacement
), shoulder, and elbow, is
also common.
arthroscopy
Inspection through an
endoscope
(a
viewing tube) of the interior of a joint,
usually for diagnostic purposes.
WHY IT IS DONE
Arthroscopy is most often used to diag-
nose disorders of the knee joint but can
also be used in other joints such as the
shoulder, hip, or wrist. The procedure
allows the surgeon to see the surface of
the bones, the ligaments, the cartilages,
and the synovial membrane. Specimens
can be taken for examination.
Some surgical procedures that used to
involve making a large incision, such as
removal of damaged cartilage, repair of
ligaments, and shaving of the patella
HOW ARTHROSCOPY IS DONE
The procedure is usually performed under general anaesthesia. The joint is
distended by injecting air or a saline solution, and the arthroscope and a probe
are inserted into it through small skin incisions. While watching the monitor, the
surgeon can repair or remove tissue, such as damaged cartilage, or drill or shave
the surface of the patella (kneecap).
Surgeon
Arthroscope
An arthroscope is a type of
rigid endoscope - a hollow
stainless steel tube
containing optical fibres,
a lens, and a light source.
Air or waterstopcocks
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