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Discogram Treatment
Lumbar discography is an injection technique used to
evaluate patients with back pain who have not responded to
extensive conservative (nonsurgical) care regimens. The most
common use of discography is for surgical planning prior to
a lumbar
fusion.
Indications for a Discogram
The indications for getting a discogram prior to a
lumbar fusion surgery are extremely variable
amongst
spine surgeons. Ordering the procedure depends on access
to a skilled discographer. A discogram is basically a very
subjective test, and if there are no experienced
discographers available, then the spine surgeon may forego
the test since a poorly done discogram does not yield any
useful information.
Lumbar discography is considered for patients who,
despite extensive conservative treatment, have disabling
lower back pain,
groin pain,
hip pain, and/or
leg pain. When a variety of spinal diagnostic procedures
have failed to elucidate the primary pain generator,
these individuals may benefit from lumbar discography
especially if spine surgery is contemplated.
Unique Aspects of Discography
It should be understood that the discogram is less about
the
anatomy of the disc (what the disc looks like) and more
about its physiology (determining if the disc is painful).
It is well known to discographers that a really
abnormal looking disc may not be painful and a minimally
disrupted disc may be associated with severe pain.
It is impossible to definitively diagnose a painful disc
without performing a discogram.
The Lumbar
MRI and CT myelogram
are very sensitive anatomic tests but are not very specific
in defining actual pain generators. The lumbar discogram, if
performed properly, is designed to induce pain in a
sensitive disc. A
spinal fusion procedure that is designed to obliterate
an internally disrupted, painful disc (pain generator) would
not be the procedure of choice if pressurization of the disc
didn’t reproduce the patient’s clinical discomfort. The
spine
surgeon needs to be absolutely sure that the level or
levels being fused are responsible for the patient’s pain.
If the fused levels were not initially painful, spine
surgery will not help, and the patient will be left with a
fused spine and probably still be in pain. Since a spine
fusion procedure carries a significant level of risk and
healing time, the more information that can be obtained
prior to back surgery the better.
Lumbar Discogram Procedure
While different discographers may vary the procedure
slightly, the following provides an overview of modern
technique for a lumbar discogram diagnosing
back pain.
History and Physical Exam
A nurse or other healthcare professional conducts the
initial interview. All of your questions and concerns should
be addressed and answered. This is the time to relate any
and all horror stories you may have heard from medical (and
non-medical) experts. Despite what you’ve been told, the
discogram is not designed to create agony.
Next, the discographer will talk with you to review the
relevant anatomy and discuss the procedure in much greater
detail. You now have a second chance to
ask questions or decide whether or not to proceed.
Initial Preparation for the Discogram
Procedure
If you agree to allow the discographer to perform this
exam, an
intravenous line is started just in case
intra-procedural medications become necessary. Usually,
sedation is avoided so as not to interfere with any
reactions or sensations you may experience.
Next, you are placed on a specialized table around which
a fluoroscopic (x-ray) unit is positioned. Your back is then
marked with an ink pen over the disc spaces that will
ultimately be examined. Then your back is thoroughly
cleansed and sterile drapes are applied. The fluoroscope
will also be sterilely draped and the discographer will be
in a sterile surgical gown.
Administration of Local Anesthesia
The goal is to anesthetize a core of tissue that extends
from your skin to the disc surface. When these tissues are
numbed a guide needle is directed towards the disc and will
just touch the outer surface of the annulus (the outer
margin of the disc).
Through this guide needle a much smaller disc needle is
advanced towards and eventually into the center of the disc.
This process should not be painful, but sometimes may be.
The discogram procedure usually takes less than an hour
to perform. You’ll have soreness from the needle punctures
that lasts several days. You may use acetaminophen,
ibuprofen or apply an ice pack for a few minutes to ease the
soreness. Some physicians prescribe short term narcotic pain
medications for use after the procedure.
Pressurizing the Discs - the Diagnostic
Portion of the Discogram Procedure
After all of the needles are placed, the discs are
"pressurized" one at a time. Pressurization consists of
injecting small amounts of a sterile liquid (usually
contrast material (x-ray dye)) into the center of the disc.
This is the most important part of the study and you must
concentrate on what you are feeling. There are essentially
three choices:
- You feel nothing
- You feel pressure
- You feel pain
If you feel pain from the injection, the pain is either:
- Familiar pain, which translates
into "ouch, that’s my pain!"
- Unfamiliar pain, which belongs to
someone else or translates into "ouch, I’ve never felt
that pain before."
After each level is pressurized, pictures are taken with
the fluoroscopic unit and the needles are removed. Usually,
a post-discogram CT is obtained to document the internal
architecture of the disc. And that’s it!
The procedure usually takes less than an hour to perform.
You’ll have soreness from the needle punctures that lasts
several days. You may use acetaminophen, ibuprofen or apply
an ice pack for a few minutes to ease the soreness.
Possible Risks and Complications of a
Discogram
As with any other invasive test, there are associated
risks and possible complications.
- The most feared complication is a disc space
infection, which can be very difficult to treat.
Fortunately, by using very strict sterile techniques
this is a very uncommon complication.
- There are extremely remote possibilities of
nerve root injury
-
Spinal headache is also a remote risk
With a skilled and experienced discographer who uses
modern discography techniques, all of these risks are very
rare.
In summary, a discogram is a preoperative study designed
to determine if an intervertebral disc is a pain generator.
The initial needle placement need not be painful. If
pressurization of a disc causes a familiar pain, then
surgical obliteration (fusion) of the pain generator(s) may
afford significant
back pain relief.
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