Dr. M. J. Bazos,
Patient Handout
Joint
Injection/Aspiration
What is done during a joint
injection/aspiration?
Joint injections
or aspirations (taking fluid out of a joint) are usually performed under local
anesthesia in the office or hospital setting. After the skin surface is
thoroughly cleaned, the joint is entered with a needle attached to a syringe. At
this point, either joint fluid can be obtained and sent for appropriate
laboratory testing or medications can be injected into the joint space. This
technique also applies to injections into a bursa or tendon to treat tendinitis
and bursitis, respectively.
What
benefit is derived from a joint aspiration
?
Joint aspiration is usually done as a
diagnostic or therapeutic procedure. Fluid obtained from a joint aspiration can
be sent for laboratory analysis, which may include a cell count (the number of
white or red blood cells), crystal analysis (so as to confirm the presence of
gout or pseudogout), and/or culture (to determine if an infection is present
inside the joint). Drainage of a large joint effusion can provide pain relief
and improved mobility. Injection of a drug into the joint may yield complete or
short-term relief of symptoms.
What
benefit is derived from a joint injection ?
Joint injections are given to treat
inflammatory joint conditions, such as rheumatoid arthritis, psoriatic
arthritis, gout and occasionally osteoarthritis. Corticosteroids are frequently
used for this procedure as they are anti-inflammatory agents that slows down the
accumulation of cells responsible for producing inflammation within the joint
space. Although corticosteroids may also be successfully used in osteoarthritis,
their mode of action is less clear. Hyaluronic acid (Hyalgan ®, Synvisc
®) is a viscous lubricating substance that may relieve the symptoms of
osteoarthritis of the knee.
Are
there situations where a joint injection should not be given
?
Yes. The most common reasons for not
performing a joint injection are the presence of an infection in or around a
joint and if someone has a serious allergy to one or more of the medications
that are injected into a joint.
What is
usually injected into the joint space
?
Most joint injections utilize
anti-inflammatory medications called corticosteroids (such as methylprednisolone
or triamcinolone). These medications act locally and have few systemic
side-effects (such as a fever, rash, or a disturbance of an internal organ). In
degenerative joint diseases such as osteoarthritis, a joint lubricant such as
hyaluronic acid (described above) may be used with aim of relieving
pain.
Which joints are usually
injected ?
Commonly injected joints
include the knee, shoulder, ankle, elbow and wrist and small joints of the hands
and feet. Hip joint injection may require the aid of an X-Ray called fluoroscopy
for guidance. Facet joints
of the lumbar
spine (low back area) may also be injected by experienced rheumatologists,
orthopaedists, anesthesiologists, and
radiologists.
What are the risks of
joint injections and aspirations
?
Common side effects include allergic
reactions (to the medicines injected into joints, to tape or the betadine used
to clean the skin, etc). Infections are extremely rare complications of joint
injections and occur
less than 1 time per
15,000 corticosteroid injections. Another uncommon complication is
"post-injection flare" - joint swelling and pain several hours after the
corticosteroid injection - which occurs
in
approximately one out of 50 patients and
usually subsides within several days. It is not known if joint damage may be
related to frequent corticosteroid injections. Generally, repeated and numerous
injections
into the same joint/site should
be discouraged. Other complications, though infrequent, include depigmentation
(a whitening of the skin), local fat atrophy (thinning of the skin) at the
injection site and rupture of a
tendon
located in the path of the
injection.
For more
information:
If you want to find a
rheumatologist in your area, check the American College of Rheumatology
membership directory. If you want more information on this or any other form of
arthritis, contact the Arthritis Foundation at (800)283-7800 or visit their Web
site at www.arthritis.org