Diagnosing Disorders of the Spine
After taking a medical history and performing a physical examination, there
are a number of tests available to the doctor to help better understand a patient’s
back problem. Some look only at anatomy, while others address the function of muscles and
coordination of the spine. Problems originating in areas other than the spine may also
cause back pain. Therefore, when diagnosing sources of back pain, doctors may also order
other types of tests, such as blood tests. Some commonly used tests include:
Function
 | Electromyograms
(EMG) are a family of tests that look at the function of the muscles and/or the nerve
roots leaving the spine. By identifying abnormal electrical signals in the muscles, the
EMG can show if muscles are functioning abnormally or if a nerve is being pinched as it
leaves the spine. It is very difficult to accurately locate the affected muscle or nerve
using EMG techniques. |
|
The "ISO" tests
include isometric, isokinetic, isotonic, and isoinertial measurements,
collectively known as dynamometry. They measure the strength of the trunk muscles.
However, current research does not support the premise that low back pain sufferers have
weaker trunk musculature than healthy individuals. |
| The Spinoscopy Examination
looks at the function of the spine in motion. By
analyzing the coordination of movement, it determines the degree of any biomechanical
impairment of the spine and the conditions under which a spinal disorder is present.
Unlike anatomical imaging techniques such as X-rays, CT, or MRI, Spinoscopy analyzes
dynamic function, incorporating incremental load increases to simulate routine daily
activities such as lifting. Spinoscopy is essentially a lumbar stress test, similar to the
stress EKG for the heart. |
Anatomy
| The CAT Scan
(Computer Assisted Tomography) is a computer enhanced test in which X-ray
"slices" are taken to give a cross sectional view of the spine. The CAT scan
shows the bones of the spine much better than the MRI, and is useful when conditions that
affect these bones are suspected. The CAT scan is commonly combined with a myelogram to
give a better picture of the spinal nerves. |
| The Discogram
is a special test where dye is injected directly into the disk. Plain X-rays and a CAT
scan can also be used to look at the disk, and may show whether or not the disk is
ruptured. |
| MRI
(Magnetic Resonance Imaging) is the most common test used to show the anatomic details of
the spine. The MRI scanner uses magnetic waves to "slice" through the spine,
layer by layer, taking pictures of each slice. The multiple pictures of the spine taken by
the MRI scanner show not only the bones of the spine, but also the nerves and discs.
However, there is a growing body of evidence that suggests that the abnormalities that
show up on the MRI scan are not always the cause of a person's problem. Anomalies, such as
bulging discs, show up frequently in people who have never had any problem with their
backs. |
| The Myelogram
is a test that uses dye to enhance the X-ray image. An abnormal myelogram may indicate
that there is pressure on the nerves of the spine, which may be caused by a herniated
disc. |
| X-rays
are ordered if there are specific reasons to suspect a fracture, infection, or p ossibly a
malignant tumor of the spine. X-rays show the bones of the lumbar spine. Most of the soft
tissue structures of the spine do not show up in conventional X-rays. |
