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FEATURE | SHERRY
Not uncommonly it begins as a localized pain and spreads.
Allodynia (tenderness to a normally nonpainful stimulus) is
common. Clothing, bumps while riding in the car, and even
the wind against bare skin will cause pain. Some children, usually
those with diffuse pain, will have multiple bodily complaints,
which help define fibromyalgia by the Yunus and Masi
criteria (see Table 1). These children typically report very high
levels of pain (10 out of 10) with an incongruently cheerful
affect, and severe dysfunction. They present themselves as
mature and accomplished teens who are perfectionistic, and
who meet the emotional needs of their peers and others rather
than their own. They are severely incapacitated, much more
than children with arthritis or mechanical limb pain, and multiple
physician visits and therapeutic failures are common.
Autonomic signs seen in CRPS usually consist of coolness
and cyanosis. These signs may not be apparent at rest but may
develop after exercising the limb. Occasionally there is increased
perspiration or dystrophic skin.
Allodynia is tested by either light touch or gentle pinching
of a fold of skin. The area of allodynia may vary in location on
repeated testing.
Painful trigger points can be found in those with fibromyalgia.
These points are reported as painful, not tender or sore,
with 3-4 kilograms of digital pressure. These points are: base of
occiput, lateral transverse process of C6, mid superior border of
the trapezius muscle, medial border of the scapula, just superior
to the spine of the scapula, superior anterior border of the
medial 2nd rib, 1 cm distal to the lateral epicondyle, mid gluteal
fold, 1 cm posterior to the greater trochanter, and 1 cm proximal
to the medical knee mortise (3). Control points should also
be tested, such as the forehead, thumbnail, shaft of the tibia, and
outer third of the clavicle (9). Those with painful control points
are, perhaps, better described as having total body pain.
Conversion symptoms are fairly common and include
numbness, bizarre gait, paralysis, or abnormal shaking or
tremors. Dizziness is a common complaint, but vestibular function
tests are normal (10).
Laboratory Tests
ALL LABORATORY BLOOD AND URINE TESTS ARE NORMAL.
Radiographs may show osteoporosis, and a bone scan is usually
normal although it can show decreased uptake, especially in
CRPS (or spotty increased uptake characteristic of adult CRPS)
(11). Magnetic resonance images can show edema, but the
anatomy is otherwise normal.
Diagnostic Pitfalls
CHILDREN THOUGHT TO HAVE AMPLIFIED MUSCULOSKELETAL
PAIN should have a careful evaluation for other causes. The
most common diagnosis I make in these children is spondyloarthropathy,
since enthesitis (inflammation at the insertion
of tendon and ligament into bone) is not a feature most
These conditions present
some of the greatest
challenges in pediatrics
but are also the most
rewarding to treat
because the child goes
from being highly
disabled to normal.
practitioners check for. Malignancies, usually spinal cord
tumors, are the most serious condition one can miss, so a
detailed neurological examination is mandatory. Arthritis has
been mistaken rarely for amplified musculoskeletal pain, but
it is usually obvious on examination. Rarely will undetected
thyroid disease in children be manifest as diffuse pain.
Disease Activity
INITIALLY AND DURING FOLLOW-UP there needs to be ongoing
assessment of pain and dysfunction. Self-report, such as a mark
on a visual analog scale or a rating of 0 - 10 on a verbal scale, is
adequate to measure pain. Functional measures can be elaborate
(such as standardized age-appropriate questionnaires) but, in
practice, asking about school attendance, walking endurance,
chores, and participation in recreational activities is sufficient.
Treatment
INITIALLY, IT IS PARAMOUNT to establish a trusting relationship
with the child and family. You have to believe that the child is
in pain since that child has been given both verbal and nonverbal
messages that the pain is all in his or her head or that he or
she is malingering. I have found it extremely useful to explain
the pain in terms of sympathetically mediated pain amplification;
this approach reinforces the reality of the pain, gives an
understandable reason for the pain, and is a mechanism with
which to introduce the treatment strategy (12).
“Further medical investigation is unnecessary, even if the
family is convinced that an insidious diagnosis has been overlooked
or that a test (even if done previously and was normal)
will establish a diagnosis.
All medications for pain need to be discontinued. Children
who are on medications for depression or anxiety disorders may
need to continue their use, but those treated with antidepressants
for pain reduction alone should stop taking the drugs.
Several of the medications used for pain will need to be tapered,
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