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Case
Report -
A 30-year-old woman with
intractable pain
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Larry
Birger, Jr., MD
The patient is a 30-year-old white female,
first presented to clinic for acute and chronic low back,
hip, and left leg pain. The acute event was occasioned by
picking up her 3 year-old son, resulting in a burning sensation
down her left leg, and midline pain in her L-5 region, “like
I had been hit with a baseball bat.” Her chronic pain began
nearly three years before, when the vehicle she was driving
was rear-ended by another vehicle. Consequent problems included:
left neck pain and weakness, left shoulder pain radiating
to her arm, and LUE weakness; bilateral low back and hip
pain (left>right), with radiation down LLE and paresthesias
of 2nd and 3rd digits; and chronic
headaches. Prior to the accident, her medical history was
remarkable only for pre-eclampsia and Cesarean section.
The
patient was seen by a PM&R group and diagnosed with
myofascial (cervical and lumbar) pain syndrome with radiculitis,
and was treated over the next two years with multiple modalities:
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Medical: various NSAIDs, narcotics, Medrol dose pack,
and muscle relaxants;
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Physical Therapy: standard regimens, home exercise program,
TENS unit, and massage;
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Injections: trigger point, joint, and epidural steroid
injections;
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Acupuncture;
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Surgery: left rotator cuff repair.
Of
these, the shoulder surgery and trigger point injections
provided the best relief (the latter usually lasting 3-4
weeks); the most effective pharmacologic agent proved to
be vicoprofen, with periodic addition of Flexeril as needed.
Multiple
diagnostic studies were also obtained:
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MRI #1 L-spine: L2/3 through L5/S1 posterior disc bulges,
which appeared to remain subligamentous;
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MRI C-spine: cervical kyphosis compatible with reflex
muscle spasm;
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MRI left shoulder: no abnormality noted;
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EMG upper extremity: normal nerve conduction study,
no signs of cervical radiculopathy;
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MRI brain: normal;
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EEG: normal;
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MRI #2 L-spine: grossly unremarkable;
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L-spine films, including flexion/extension views: normal.
Treatment
for the acute exacerbation (one of several such instances
[e.g., falls] over three years) with PT, Vicoprofen, and
Flexeril was successful. Subsequently, the patient presented
complaining that her previous care was too disjointed, and
requesting establishment of a PCP relationship. We decided
that we would review all her treatment to date, re-evaluate
her diagnosis, and explore any further therapeutic options.
Thus
far the patient has been seen in clinic on three occasions.
Apart from findings consistent with acute events (as above,
plus a subsequent left ankle injury), physical exam revealed
a frustrated but pleasant, obese, 30 year-old white female,
ambulating with a cane. She evidenced varying degrees of
pain with certain movements (e.g., rising from chair) and
compensatory antalgic postures. Spinal ROM was limited in
all directions, with approximately 5 degrees extension,
60-75 degrees flexion, and 10 degrees lateral flexion. Lumbar
spinous processes were somewhat tender to palpation, with
tenderness to palpation of paralumbar musculature. Left
lower back, and to a lesser degree, buttock and proximal
lateral thigh, were tender as well, with foci just lateral
(left) to the lumbar spine and in the left gluteus medius
which, when palpated, were tender and caused laterally and
inferiorly radiating pain across her lower back, and buttock
and upper thigh, respectively. Lt. Straight leg test was
positive, and hypesthesia of left foot, and especially 2nd
and 3rd digits, was noted.
Based
on an extensive review of the patient’s past medical records,
and given her exam findings, the diagnosis of myofascial
lumbar pain syndrome was deemed appropriate, and we are
currently in the process of exploring appropriate treatment
modalities. In the interim, the patient has been placed
on Neurontin 600mg qhs (the medication makes her sleepy,
precluding b.i.d. or t.i.d. dosing; dosage was begun at
300mg), Vicoprofen 7.5/200 q4-6h prn, Flexeril prn, and
physical therapy.
DISCUSSION
Although
often equally frustrating for patient and physician, chronic
muscle pain without obvious structural etiology is a frequent
and important complaint in the primary care setting. Of
these, myofascial pain syndrome (MPS) may be one of the
most common causes of chronic pain.1
This syndrome was originally described in the 1940’s,2 and although some challenge its validity, and while as yet there
are no widely accepted or consensus-generated criteria,
there seems to be substantial support across various specialties
as to both its existence and characteristic findings.3
As classically described, MPS “is characterized by the presence
of regional pain and the presence of defined ‘exquisitely’
painful trigger points in a taut band of muscle, that produce
characteristic patterns of referred pain on palpation and
a local twitch response to mechanical stimulation or needling.”
These myofascial trigger points are loci of “hyperirritability
in a muscle or its associated connective tissue that, when
compressed, [are] locally tender and, if sufficiently hypersensitive,
give rise to referred pain and referred tenderness; [they]
may also initiate remote autonomic phenomena.”2
These trigger points are found in the muscle belly, are
always tender, and refer pain in characteristic distributions
when palpated. Additionally, other findings associated with
MPS have been enumerated, including: normal neurologic exam;
reduced pain with local anesthetic injection; taut bands;
pain characterized as “dull,” “achy,” or “deep;” palpable
nodules; pain exacerbated by stress; decreased range of
motion; and ropiness in the muscle.3
MPS
can occur in various muscle groups – even manifesting neurologically,
such as headache, dizziness, and neurocognitive disturbances
– but the most commonly affected sites are posterior neck,
low back, shoulders and chest.4
The pathophysiology of MPS is unclear, and since it often
occurs in conjunction with other conditions, such as trauma
or overuse injury, diagnosis can be difficult. A number
of other conditions produce chronic pain similar in varying
respects to MPS, such as tension-vascular headaches, thoracic
outlet syndrome, TMJ, multiple sclerosis, entrapment neuropathies,
radiculopathies, and especially fibromyalgia (FM).5
A comparison with FM in particular allows for a helpful
conceptual and diagnostic clarification of MPS.
Table
11 shows a comparison between these two syndromes.
Table
1. Clincal Features of Fibromyalgia versus Myofascial
Pain
|
Variable |
Fibromyalgia |
Myofascial
Pain |
|
Gender |
90%
female |
- |
|
Examination |
Tender
points |
Trigger
points |
|
Pain |
Generalized |
Localized |
|
Fatigue |
Prominent |
- |
|
Course |
Chronic |
Self-limited
(?) |
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In
FM the patient’s pain is generalized, and while there are
characteristic tender points, these do not produce the locally
radiating pain found with palpation of MPS trigger points.
Figure 11 further elaborates this important distinction,
illustrating the regional nature of MPS pain; the loci are
very similar to those found in our patient.
Figure
1. Trigger Points in Myofascial Pain Syndrome.
(Illustrated by Ki-Tae Mok, MD)
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Treatment
of MPS is multi-factorial. The first step (very well evidenced
with our patient) is to take the patient’s complaints seriously,
regardless of the absence of any ‘objective’ findings such
as MRI abnormalities, followed by a thorough history. To
perform this adequately may require scheduling one appointment
simply to obtain the history, and another for exam and discussion
of therapeutic options. Assuming other etiologies have been
ruled out and/or appropriately addressed, there are a number
of modalities to pursue. A common first-line treatment (not
tried with our patient, for unknown reasons) is the ‘spray
and stretch’ technique, where a coolant spray is applied
to the muscle and then the muscle passively stretched to
its normal maximum length, to the point of mild discomfort.
Various trigger point injection techniques have been utilized,
including lidocaine, dry needling (equally as effective,
but probably more painful for the patient), and botulinum
toxin. One study concluded that ultrasound treatment and
trigger point injections were equally effective, when combined
with neck stretching exercises.6
Corticosteroid trigger point injections are not of increased
efficacy and are not indicated for MPS.
Beyond
these, physical therapy, chiropractic and massage may be
useful adjuncts. NSAIDs may be helpful for analgesia, but
their anti-inflammatory action in MPS is questionable.5
Trials with low-dose tricyclic antidepressants may also
be of some benefit; muscle relaxants simply for MPS are
not particularly effective. Finally, addressing factors
such as workplace ergonomics, posture, obesity, proper footwear,
psychosocial issues, and minimizing subsequent injuries
is essential to insure treatment success and minimize recurrence.
REFERENCES
- Goldenberg
D. Differential Diagnosis of Fibromyalgia. UpToDate,
10:2.
- Aronoff
GM. Myofascial Pain Syndrome and Fibromyalgia:
A Critical Assessment and Alternate View. Clinical
Journal of Pain. 1998;14:74-8.
- Harden
R, Bruehl SP, Gass S, et al. Signs and Symptoms
of the Myofascial Pain Syndrome: A National Survey of
Pain Management Providers. Clinical Journal of Pain.
2000;16:64-72.
- Braunwald
E, Fauci AS, Kasper DL, et al., ed. Harrison’s Principles
of Internal Medicine, 15th ed., p. 2012.
- Fomby
EW, Mellion MB. Identifying and Treating Myofascial
Pain Syndrome. The Physician and Sportsmedicine.
1997;25:2 (reference at: www.physsportsmed.com/issues/1997/02feb/fomby2.htm)
- Esenyel
M, Caglar N, Aldemir T. Treatment of Myofascial
Pain. American Journal of Physical Medicine & Rehabilitation.
2000;79:48-52.
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