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Flashcards in Chapter 5. Diagnosis of Pain States Deck (80):

252. A59-year-old female comes to your office complaining
of moderately severe low back pain
and right buttock pain which is exacerbated
with prolonged sitting. On physical examination
there is sciatic notch tenderness and the
pain is exacerbated with flexion, adduction,
and internal rotation of the right hip. Which of
the following is the most likely diagnosis?
(A) L5-S1 facet syndrome
(B) Piriformis syndrome
(C) Sacroiliac (SI) joint syndrome
(D) Sciatica
(E) L3 radiculopathy

252. (B) The piriformis syndrome was originally
described by six common characteristics
(1) trauma; (2) pain in the muscle with sciatica
and difficulty in walking; (3) worsening with
squatting or lifting; (4) a sausage-like mass
within the muscle; (5) positive Lasègue sign;
and (6) gluteal atrophy. The female to male
ratio is 6 to 1.
There are many approaches to evaluate
piriformis syndrome. One method is in the sitting
position which involves the examiner
stretching the piriformis muscle by passively
moving the hip into internal rotation reproducing
buttock pain which is relieved by the
examiner passively moving the hip into external
rotation. The patient then actively rotates
the hip against the resistance which reproduces
buttock pain. Furthermore, there is generally
point tenderness on palpation of the
belly of the piriformis muscle. There tends to
be prolongation of the H-reflex with flexion,
adduction, and internal rotation.


253. A77-year-old female comes to your office complaining
of 6 months of severe right buttock
pain radiating into the right lower leg. The pain
is also present at night and not uncommonly
interferes with sleep. The pain is severe with
sitting or lying on her back or right side, however,
quickly dissipates with normal erect posture.
Which of the following is the most likely
(A) Snapping bottom
(B) Sciatica
(C) Radiculopathy
(D) Piriformis syndrome
(E) Weaver’s bottom

253. (E) In classic weaver’s bottom (ischiogluteal
bursitis)—the patients invariably get pain sitting
which goes away upon standing or lying
on their contralateral side. However, the pain
promptly returns upon resuming a seated position.
Typically, the patient can consistently
point to the spot where it hurts with their finger
and state “it hurts right here.” On physical
examination, tenderness is evoked with palpation
over the ischiogluteal bursa.


254. A 53-year-old male comes to your office complaining
of foot pain (predominantly in the
heel—but also with diffuse plantar symptoms)
which also occurs at night and can be exacerbated
by prolonged standing or walking. It is
associated with weakness of the phalanges
(impairing the pushing off phase of walking) as
well as sensory loss and paresthesia. After a
complete history and physical examination are
completed, which of the following is the next
most appropriate step?
(A) Magnetic resonance imaging (MRI) of
the ankle
(B) MRI of the lumbar spine
(C) Initiate anti-inflammatory medications
(D) Trial of arch support
(E) Electrodiagnostic testing

254. (E) Imaging studies are most appropriate with
bony point tenderness or when the differential
diagnosis is likely calcaneal stress, fracture
Paget disease, tumors, calcaneal apophysitis
(Sever disease in adolescents), or calcaneal
stress fracture. The most appropriate diagnostic
evaluation for suspected tarsal tunnel syndrome
is electrodiagnostic evaluation.


255. A 53-year-old male comes to your office complaining
of foot pain (predominantly in the
heel—but also with diffuse plantar symptoms)
which also occurs at night and can be exacerbated
by prolonged standing or walking. It is
associated with weakness of the phalanges
(impairing the pushing off phase of walking) as
well as sensory loss and paresthesia. Which of
the following is the most likely diagnosis?
(A) Morton neuroma
(B) Peripheral neuropathies
(C) Medial plantar nerve entrapment
(D) Tarsal tunnel syndrome
(E) March fracture

255. (D) The tarsal tunnel located behind and inferior
to the medial malleolus. It is bounded on
the lateral aspect by the tibia and medially by
the flexor retinaculum (laciniate ligament). Its
contents include the tibial nerve, posterior tibial
tendons, flexor digitorum longus tendon, flexor
hallucis longus tendon, tibial artery, and tibial
vein. Within the tarsal tunnel or immediately
distal to it, the tibial nerve divides into the
medial and lateral plantar nerves. The calcaneal
branch originates variably above or below the
flexor retinaculum to supply the heel and calcaneal
skin. The tarsal tunnel syndrome most
commonly arises from trauma (eg, fractures,
ankle dislocations) and is characterized by foot
pain and paresthesia, as well as potentially by
sensory loss and Tinel sign at the ankle. The
pain may be similar to carpal tunnel syndrome
in that it often occurs at night. Furthermore, it
may be exacerbated by prolonged standing or
walking. Amarch fracture is a stress fracture of
the metatarsal bone. The second and third
metatarsals are the most common sites. Patients
complain of increased intensity of pain with
activity or exercise. The pain is localized to the
site of the fracture.


256. A47-year-old female comes to your office complaining
of an aching forearm with discomfort
and numbness in the thumb and index finger,
and weakness in the hand. Apositive Tinel sign
is present in the forearm. Which of the following
is the most likely diagnosis?
(A) Anterior interosseous nerve syndrome
(B) Posterior interosseous nerve syndrome
(C) Ulnar nerve entrapment
(D) Pronator syndrome
(E) Radial nerve entrapment

256. (D) Pronator syndrome may result from compression
of the median nerve proximal to the
branching of the anterior interosseous nerve.
Patients with pronator syndrome generally
complain of an aching discomfort of the forearm,
numbness in the thumb and index finger, and weakness in the hand. On physical examination
there may be tenderness over the proximal
part of the pronator teres muscle that is
exacerbated by pronation of the forearm
against resistance. Resisted pronation may also
result in paresthesia in the distribution of the
median nerve. A positive Tinel sign is often
present at the proximal edge of the pronator
muscle. If the entrapment is under the bicipital
aponeurosis this may result in weakness of the
pronator muscle and depending on the degree
of compression, weakness of other muscles (eg,
long flexor muscles of the fingers and thumb,
abductor pollicis brevis)


257. Complex regional pain syndrome type II
(CRPS II) differs from CRPS I because in CRPS II
there is
(A) allodynia
(B) movement disorder
(C) sudomotor and vasomotor changes
(D) evidence of major nerve damage
(E) severe swelling

257. (D) CRPS I and CRPS II are clinically indistinguishable.
The only difference is that in CRPS II
there is evidence of major nerve damage.


258. Which of the following range is the temperature
most appropriate to use as a stimulus
when evaluating warm temperature sensation?
(A) 25°C to 30°C
(B) 30°C to 35°C
(C) 35°C to 40°C
(D) 40°C to 45°C
(E) 45°C to 50°C

258. (D) The temperature range to test warm temperature
sensation is 40°C to 45°C—usually
done via a glass or metal tube with hot (40°C-
45°C) water. Temperatures higher than 45°C
are generally perceived as painful.


259. Which of the following range is the temperature
most appropriate to use as a stimulus
when evaluating cold temperature sensation?
(A) −5°C to 0°C
(B) 0°C to 5°C
(C) 5°C to 10°C
(D) 10°C to 15°C
(E) 15°C to 20°C

259. (C) The temperature range to test cold temperature
sensation is 5°C to 10°C—which may be
done with a thermophore. Temperatures lower
than 5°C are generally perceived as painful.


260. Which of the following may potentially facilitate
or perpetuate myofascial trigger points in
some patients?
(A) Low creatine kinase
(B) Low aldolase
(C) Low cholesterol
(D) Low vitamin D
(E) Low vitamin B12 or folate

260. (E) Low levels of vitamin B12 and/or folate may
be associated with increased trigger points in
many patients who suffer from myofascial pain
syndrome. Multiple coexisting systemic conditions
may also be associated with myofascial
pain syndrome and should be investigated
in patients with severe painful myofascial trigger


261. A 39-year-old male with persistent coughing
attributed to upper respiratory infection (URI)
comes to your office complaining of moderate
anterior chest wall pain—it is only on the left
side—predominantly over the second and third
costal cartilages. Bulbous swellings and point
tenderness are present at these sites. Which of
the following is the most appropriate diagnosis
for this patient?
(A) Intercostal neuralgia
(B) Tietze syndrome
(C) Acute myocardial infarction
(D) Pneumonia
(E) Pleurisy

261. (B) Tietze syndrome (costochondritis) should
only be diagnosed after other diagnoses are
ruled out. It is most frequently unilateral
involving the second and third costal cartilages
and is characterized by mild to moderately
severe anterior chest wall pain. The pain is typically
localized in the region of the costal cartilages
but may occasionally radiate to the arm
and shoulder. Tietze syndrome occurs more
commonly under the age of 40 years. On
physical examination, tenderness to palpation
as well as bulbous swelling over the costochondral
junctions may be found.


262. A 66-year-old woman who did not have a history
of trauma comes to your office complaining
of acute, severe, constant medial right knee
pain for 6 weeks. MRI imaging demonstrated
extensive narrow edema of the medial femoral
condyle with significant soft tissue edema
around the superficial and deep compartment
of the medial collateral ligament (MCL) but
without MCL disruption. Which of the following
is the most likely diagnosis?
(A) Stress fracture
(B) MCL tear
(C) Medial meniscal tear
(D) Spontaneous osteonecrosis of the
knee (SONK)
(E) Medical femoral condyle contusion

262. (D) Spontaneous osteonecrosis of the knee
(SONK) is an entity whose precise pathogenesis
remains unclear. The pain may be present at
rest and is generally well-localized without
trauma or associated incited event. It is classically
defined as unilateral and spontaneous
with predilection for the medial femoral
condyle. It occurs typically in the elderly population
(> age 60) and is three times more
common in women than men. Initial radiographs
tend to be normal.


263. A 49-year-old male comes to your office after
climbing several mountain passes in the
Pyrenees on a bicycle with thigh complaints.
He relates to you that he developed a painful
sensation on the lateral aspect of his right thigh,
which lasted for about a week. This was followed
by numbness and paresthesia in the
same location. Physical examination revealed
sensory loss in the same location. Which of the
following is the most likely diagnosis?
(A) Tensor fascia lata syndrome
(B) Meralgia paresthetica
(C) Iliotibial band syndrome
(D) Greater trochanteric bursitis
(E) Lumbar radiculopathy

263. (B) Meralgia paresthetica is a painful mononeuropathy
of the lateral femoral cutaneous nerve
(LFCN). Although it may be idiopathic in
nature it is commonly caused by focal entrapment
of the LFCN as it passes through the
inguinal ligament. Although there have been
numerous reported associated conditions,
some of these include weight change (eg, obesity,
pregnancy), possibly external compression
(eg, seat belts, tight clothing), perioperative
factors/trauma, retroperitoneal tumors, and
strenuous walking/cycling (the iliopsoas muscle
and tensor fascia lata are heavily involved in
walking and/or cycling movement).


264. A43-year-old male runner comes to your office
complaining of a dull ache in the anterior
aspect of the lower legs bilaterally which occurs
about 10 minutes into his running routine each
time he runs and dissipates with rest. The
patient states that he needs to stop running
because of this ache and also notes dysesthesia
in the first web space of both feet. Which of
the following is the most likely diagnosis?
(A) Shin splints
(B) Stress fractures
(C) Chronic osteomyelitis
(D) Periostitis
(E) Chronic exertional anterior compartment
syndrome of the lower leg

264. (E) Chronic exertional compartment syndrome
of the anterior tibial compartment may occur in
runners, soccer players, and racers and may
present with a fullness in the anterior compartment,
exacerbation of pain on passive dorsiflexion
of the great toe, weakness of the
extensor hallucis longus muscle, and decreased
sensation in the first web space. Symptoms are
usually bilateral 75% to 95% of the time


265. A32-year-old construction worker felt a sharp
pain in his back radiating down to the heel of
his right foot after lifting a large, metal girder.
Two days later he noticed numbness in the sole
of his right foot and fifth toe. Physical examination
is notable for a decreased ability to walk
on his toes, a positive straight leg raising test on
the right, and a markedly diminished ankle
jerk reflex. Which of the following is the most
likely diagnosis?
(A) L4-5 herniated disc
(B) Discogenic low back pain
(C) L5-S1 herniated disc
(D) Spinal stenosis
(E) Piriformis syndrome

265. (C) Symptoms from an L5-S1 herniated disc
are typically experienced in the distribution of
the S1 nerve root. These symptoms may
include pain or sensory changes in the calf, lateral
border of the foot, heel, sole, and sometimes
fourth and fifth toes. On physical
examination, the patient may have diminished
strength in the gastrocnemius, soleus, and the
peroneus longus and brevis muscles. An L4-5
herniated disc most frequently results in L5 symptoms, which include diminished sensation
in the lateral leg, dorsum of the foot, and
the first two toes. Spinal stenosis is narrowing
of the spinal canal that occurs with aging.
Patients may present with decreased strength
and loss of sensation, but with central stenosis
it is usually nondermatomal. Piriformis syndrome
is an uncommon cause of buttock pain
and/or sciatica that is caused by sciatic nerve
compression by the piriformis muscle. Although
sciatica is often present, pain from piriformis
syndrome is nonadicular, and hence straight
leg raising tests should not be positive.
Discogenic pain is pain that results from internal
disc disruption. The neurologic examination
should be nonfocal when pain results
solely from internal disc derangement.


266. An 80-year-old man presents with a 2-year
history of low back pain radiating down from
both legs to his ankles. He also notes numbness
in his left foot and slight weakness. The pain is
increased with walking and relieved within
seconds of cessation of activity. Leaning forward
eases his pain and lying supine relieves it.
Which of the following is the most likely
(A) Herniated nucleus pulposus
(B) Facet arthropathy
(C) Muscle spasm
(D) Arachnoiditis
(E) Spinal stenosis

266. (E) As we age, our spinal canal starts to narrow.
This narrowing is a result of many different
processes including disc bulging from a progressive
loss of disc height and elasticity,
hypertrophy of the facet joints and ligamentum
flavum and osteophyte formation.
Technically, the term “spinal stenosis” can refer
to central canal stenosis, lateral recess stenosis,
or foraminal stenosis. The typical presentation
of someone with spinal stenosis is an elderly
person with low back and leg pain brought on
by walking, especially on stairs or hills.
Frequently, the pain is bilateral. In contrast to
vascular claudication, patients with neurogenic
or pseudoclaudication often find that the cessation
of walking brings immediate pain relief.
Like spinal stenosis, facet arthropathy is more
common in the elderly, but the pain does not
typically radiate into the lower leg and is usually
not associated with loss of sensation.


267. A 31-year-old woman presents to your office
with marked pain and swelling in her ankle
6 weeks after an open reduction internal fixation
with casting. On examination, the ankle is
warm and erythematous. Lightly touching the
ankle with a cotton swab evokes severe, lancinating
pain. You suspect CRPS I. Which of the
following tests will confirm your diagnosis?
(A) Lumbar sympathetic block
(B) Phentolamine infusion test
(C) Triple phase isotope bone scan
(D) Erythrocyte sedimentation rate
(E) None of the above

267. (E) In the early 1990s, a panel of experts
reached a consensus that the terms “reflex sympathetic
dystrophy” and “causalgia” had lost
their utility as clinical diagnoses and suggested
a new nomenclature be adopted. The new
terms designated for these conditions are “CRPS
types I and II”. According to the new diagnostic
criteria, CRPS need not be maintained by
sympathetic mechanisms. A three-phase isotope
bone scan is often positive in CRPS, but a
normal bone scan does not exclude the diagnosis.
Erythrocyte sedimentation rate is a nonspecific
test that is positive in many painful conditions
including infection, inflammatory arthritides
and inflammatory myopathies. As a syndrome,
CRPS is diagnosed by history and physical
examination. For CRPS I, the diagnostic criteria
include (1) an initiating noxious event; (2) spontaneous
pain and/or allodynia occur outside
the territory of a single peripheral nerve, and
are disproportionate to the inciting event; (3)
there is or has been evidence of edema, cutaneous
perfusion abnormalities, or abnormal
sudomotor activity, in the region of pain since
the inciting event; and (4) the diagnosis is
excluded by the existence of any condition that
would otherwise account for the degree of pain
and dysfunction.


268. A 46-year-old man complains of worsening
back and new onset leg pain and paresthesia
10 weeks after an L4-S1 posterior spinal fusion.
One week after the surgery, the patient
reported 85% pain relief. Which radiologic test
would be most appropriate for detecting the
cause of failed back surgery syndrome (FBSS)
in this patient?
(A) Computed tomographic (CT) scan with
(B) Myelography
(C) Epidural mapping via the injection of
contrast under fluoroscopy through a
catheter inserted through the caudal
(D) T2-weighted MRI with contrast
(E) Further radiologic study is not indicated
at this point

268. (D) The type and timing of pain after spine surgery
provide important clues as to the possible
diagnosis. For example, no change in a patient’s
pain pattern after surgery may indicate that
either the wrong surgery was done or the procedure
was technically unsuccessful. In this
case, the patient experienced initial pain relief,
which was followed by worsening back pain
and new-onset leg pain several weeks later.
Possible causes of this scenario include epidural
fibrosis, arachnoiditis, discitis, battered root
syndrome with perineural scarring, or an early
recurrent disc herniation. Pseudoarthrosis,
juxtafusional discogenic pain, and lumbar instability
can also be causes of FBSS, but in these
cases the recurrence of pain typically occurs
much later. For detecting disc pathology, MRI is
more sensitive than CT or myelography. It is
also more sensitive than CT for identifying contrast
enhancement. For the possible etiologies
that fit this patient’s pain history (ie, arachnoiditis,
epidural fibrosis, and discitis), contrast
enhancement with gadolinium will greatly
enhance the sensitivity of MRI. Epidural mapping
via the injection of radiopaque contrast
under fluoroscopy through a catheter inserted
through the caudal canal is sometimes used to
determine the location of epidural scar tissue in
FBSS patients, often as a precursor to epidural
lysis of adhesions (ie, Racz procedure) or
epiduroscopy. However, this procedure provides
very little additional information. In the patient with implanted hardware, foreign ferromagnetic
metal objects give rise to local distortion
of the magnetic field, which can greatly
degrade MRI results. When implants are made
of non-superparamagnetic materials like titanium,
MRI distortion is less but the anatomy
may still be obscured. Since this patient did not
have hardware implanted, this should not deter
the use of MRI. Generally, T2-weighted images
are more sensitive for detecting pathology,
whereas T1-weighted images are better for discerning
anatomy. The use of MRI to follow a
stable, pathologic condition of the lumbar spine
is controversial. The use of MRI to evaluate a
patient with chronic low back pain who has
recently undergone spine surgery and presents
with new symptoms is justified


269. Which of the following is false regarding discogenic
low back pain?
(A) Sitting bent forward subjects the
intervertebral disc to a greater amount
of pressure than lying down, standing
or sitting with one’s back straight
(B) It is often diagnosed by using
provocative discography
(C) Because of their caudad position in the
spine, the lower lumbar discs are most
prone to degenerative disc disease (DDD)
(D) Studies have shown a genetic
predisposition to DDD
(E) Intradiscal steroids are an effective
means for treating DDD

269. (E) Sitting bent forward subjects the lumbar
intervertebral discs to greater stress than standing,
sitting with one’s back straight, or lying
down. This helps explain why patients with
discogenic low back pain often present with
sitting intolerance. Although controversial,
discography, with or without CT scanning, is
still commonly used to diagnose discogenic
pain. Patients at high risk for false-positive
discography include those with psychopathology
and previous back surgery. The lower
lumbar discs are more likely to develop degenerative
changes, and hence become pain generators,
than more cephalad discs because of
the increased load they bear. Recent studies
have shown a genetic predisposition for both
degenerative disc disease and sciatica. Several
prospective studies have been conducted evaluating
intradiscal steroids in patients with
discogenic low back pain, and none have found
them to be efficacious.


270. Which of the following statements concerning
central pain is true?
(A) Spinal cord injury is the leading cause of
central pain in the United States
(B) Lesions involving spinothalamocortical
pathways are necessary and sufficient to
cause central pain
(C) Central pain is a common sequelae
following neurosurgic procedures
(D) Motor cortex stimulation is an effective
means to treat central pain
(E) The most typical presentation of central
pain is a spontaneous, burning sensation
on the entire body contralateral to
the lesion site

270. (D) Owing to its high incidence, stroke is the
leading cause of central pain in the industrialized
world. The chance of developing central
pain following spinal cord injury is higher than
after stroke (30%-50% vs 8%), but the overall
number of stroke patients with central pain is
higher. Syringomyelia is the disorder with the
highest incidence of central pain (60%-80%).
According to neurosurgical studies conducted
by V. Cassinari and C.A. Pagni in the 1960s,
injury to spinothalamocortical pathways is necessary
but not sufficient to cause central pain.
The reason why some patients develop central
pain but others with identical injuries do not is
unknown. Central pain may occur after neurosurgical
procedures and intracranial bleeds,
but these are unusual occurrences. There are
now several prospective studies showing
motor cortex stimulation to be an effective
treatment for central pain. There is no typical
presentation for central pain. While spontaneous
pain is almost universal, allodynia also
affects a majority of central pain patients. The
time lag between the injury and onset of pain,
and the location of central pain are extremely


271. Which of the following is not commonly used
to diagnose the level of nerve root involvement
in radicular pain?
(B) CT scan
(C) Selective nerve root block
(D) Electromyography (EMG)/nerve
conduction studies (NCS)
(E) Epidural injections with local anesthetic
and steroids

271. (E) MRI is usually the first test used to evaluate
new-onset radicular pain. CT scan is less sensitive
than MRI for detecting disc pathology, but
is used in patients with pacemakers, spinal
hardware (owing to the poor resolution of MRI
in patients with ferromagnetic metal objects)
and when MRI is not available. Selective nerve
blocks are sometimes used to diagnose nerve
root pathology prior to surgery, but there is little
evidence as to whether or not this improves
outcomes. Although the terms are sometimes
used interchangeably, selective nerve blocks are
not the same as transforaminal epidural injections.
Since transforaminal epidural injections
typically result in injectate spread to contiguous
spinal levels, they cannot be considered diagnostic.
In addition to providing information
about the site of nerve root lesions, EMG/NCS
can help determine whether or not the lesion is
axonal or demyelinating; whether it is focal,
multifocal or diffuse; and the age, severity, and
prognosis of the lesion. QST is a subjective test
used to evaluate large and small fiber neuronal
dysfunction. It may be helpful in clarifying
mechanisms of pain, diagnoses, and guiding
treatment. It is not used to diagnose nerve root


272. Which of the following conditions is not generally
associated with a painful neuropathy?
(A) Chronic renal failure
(B) Celiac disease
(D) Fabry disease
(E) Amyloidosis

272. (A) Chronic renal failure is associated with
large, myelinated fiber loss that is rarely
painful. Celiac disease is a chronic inflammatory
enteropathy resulting from sensitivity to
gluten. Neurologic complications are estimated to occur in approximately 10% of patients with
peripheral neuropathy and ataxia being the
most common. The neuropathy is usually sensory,
although infrequently motor weakness
may develop. There is some evidence that the
neurologic symptoms associated with celiac
disease may be ameliorated by a gluten-free
diet. Peripheral neuropathies are reported to
affect up to 35% of AIDS patients, being more
common in later stages of the disease. The most
common neuropathy in AIDS patients is a
distal sensory polyneuropathy caused by the
human immunodeficiency virus (HIV). Other
causes of neuropathy in AIDS patients include
toxic neuropathies from medications, co-infection
with cytomegalovirus (CMV) and other organisms,
and vitamin B12 deficiency. Fabry disease
is an X-linked, lysosomal storage disease that
involves the accumulation of galactosylglucosylceramide
because of deficiency of α-galactosidase
A. It usually presents in adulthood; if
symptoms occur in childhood they usually take
the form of a painful neuropathy. Amyloidosis
may result in a painful peripheral or autonomic
neuropathy secondary to deposition of amyloid
in nervous tissue. In one study, 35% of
patients with amyloidosis were found to have
peripheral neuropathy.


273. Apreviously healthy 31-year-old woman presents
to her internist with generalized muscle
pain, most prominent in her right thigh. The pain
travels down the back of her leg to the bottom
of her foot. She also notes progressive numbness
and weakness in her arms and legs.
Walking is difficult and a loss of fine motor
control makes routine tasks like eating a challenge.
A review of her medical record reveals
an URI 3 weeks earlier. Which of the following
is the most likely diagnosis?
(A) Multiple sclerosis
(B) Guillain-Barré syndrome
(C) Chronic fatigue syndrome
(D) Acute lumbar and cervical
(E) Diabetic neuropathy

273. (B) The patient’s symptoms are most consistent
with Guillain-Barré (GB) acute inflammatory
demyelinating polyneuropathy. Patients
with GB syndrome generally present with diffuse
muscular or radicular pain followed by
sensorimotor dysfunction. Most, but not all
(72%) patients with GB syndrome experience
pain during the course of their illness. GB syndrome
affects 1 to 1.5 people per 100,000 and
shows no age or gender preference. About 60%
to 70% of cases are preceded by an URI or gastrointestinal
(GI) illness 1 to 3 weeks before
symptoms begin. Cerebrospinal fluid (CSF)
analysis reveals normal pressures, increased
protein and no cells. The pathology of GB syndrome
is demyelination, with most patients fully
recovering. Multiple sclerosis is a demyelinating
disease that typically presents in early adult
life. The most common presenting symptom
of multiple sclerosis is ocular complaints,
which affects most patients at some time during
the course of their illness. Spinal cord lesions
can produce a myriad of sensorimotor problems
including weakness, spasticity, hyperreflexia,
bladder dysfunction, sensory loss, and
diminished temperature sensation and proprioception.
Central dysesthetic pain affects
approximately 20% of multiple sclerosis
patients. The diagnosis of multiple sclerosis is
usually supported by MRI, with or without
CSF analysis. Although muscle pain and weakness
may be present in chronic fatigue syndrome
(CFS), the hallmark of this disorder is
disabling physical and mental fatigue present
for more than 6 months. There is no firm data
causally linking viral infection to CFS despite
frequent reported associations. The most
common presentation of acute radiculopathy is
pain or sensory changes in a lower extremity.
The most common form of diabetic neuropathy
is distal, symmetrical polyneuropathy. It is predominantly
a sensory disturbance, occurring
in a stocking-glove distribution. Because the
feet are innervated by the longest nerves in the
body, they are usually the first part of the body
to be affected. Other types of neuropathy that
may be present in diabetics include lower
extremity proximal motor neuropathy, truncal
neuropathy, cranial mononeuropathy, and autonomic
neuropathy. The cause of diabetic neuropathy
is most likely related to metabolic and
ischemic nerve injury


274. Which of the following statements is true
regarding SI joint pain?
(A) The SI joint is a diarthrodial synovial
joint designed primarily for stability
(B) Patrick’s and Gaenslen’s tests are definitive
diagnostic tests for SI joint pain
(C) CT scanning is the most sensitive means
for diagnosing SI joint pain
(D) Lifting heavy objects is the one of the
most common causes of SI joint injury
(E) When diagnostic blocks fail, surgery can
usually provide long-term pain relief

274. (A) The SI joints are large, paired, diarthrodial
synovial joints whose primary functions are
stability and dissipating truncal loads. The
joints are also involved in limiting x-axis rotation
and in women, parturition. There are literally
dozens of provocative tests that have
been advocated as screening tools for SI joint
pain, but several studies have shown that these
tests lack both specificity and high sensitivity.
On a similar note, CT scanning may show SI
joint pathology in over 30% of asymptomatic
control patients, and be negative in over 40% of
patients with SI pain. The most reliable method
for diagnosing SI joint pain is through diagnostic
local anesthetic blocks. The mechanism
of SI joint injury has been described as a combination
of axial loading and sudden rotation.
Common causes of SI joint pain include motor vehicle accidents, falls, athletic injuries, spondyloarthropathies,
and pregnancy. SI joint injections
with corticosteroids have been shown in
some but not all studies to provide short-term
pain relief. SI joint pain is usually not amenable
to surgical correction.


275. Which of the following statements regarding
headaches is false?
(A) The International Headache Society’s
diagnostic criteria for cervicogenic
headaches includes unilaterality of
symptoms and relief of pain by
diagnostic anesthetic blocks
(B) Migraine with aura is more common
than migraine without aura
(C) In chronic tension-type headache, the
average headache frequency is equal to
or greater than 15 days per month
(D) Cluster headaches are more prevalent in
men than in women
(E) Tricyclic antidepressants are a mainstay
of treatment for both migraine and
tension-type headaches

275. (B) In population-based studies, migraine without
aura is about twice as frequent as migraine
with aura. Major criteria for the diagnosis of
cervicogenic headache include signs and symptoms
of neck involvement such as the precipitation
of head pain by neck movement or
external pressure over the upper cervical or
occipital region, restricted range of motion in
the neck, unilaterality of head pain with or
without shoulder or arm pain, and confirmatory
evidence by diagnostic anesthetic blocks.
Chronic tension-type headache differs from
episodic tension-type headache in that the
average headache frequency is equal to or
greater than 15 days per month or 180 days
per year. A shift from peripheral to central
mechanisms is believed to play a role in the
evolution of episodic to chronic tension-type
headache. Cluster headaches typically present
as a series of intense unilateral headaches
occurring over a period of 2 weeks to 3 months.
They are associated with unilateral autonomic
features such as nasal congestion, rhinorrhea,
miosis, or lacrimation. The attacks are usually
brief, lasting between 15 and 180 minutes, and
occur in the orbital, supraorbital and/or temporal
regions. Unlike migraine headaches,
tension-type headaches, temporal arteritis, and
cervicogenic headaches, cluster headaches are
more frequent in men, with an average male to
female ratio of 5 to 1. Tricyclic antidepressants
have been shown in numerous clinical trials to
be effective in the prevention of both migraine
and tension-type headaches.


276. Which of the following statements regarding
postamputation pain is correct?
(A) Vascular conditions are the leading
cause of both lower and upper
extremity amputations
(B) There is no relationship between
persistent stump pain and phantom
limb pain in amputees
(C) The intensity of pain and the length of
the phantom increases with time
(D) Phantom breast pain is a common cause
of postmastectomy pain
(E) Phantom pain was first described in the
American Civil War

276. (D) Phantom breast pain occurs in roughly 20%
of mastectomy patients, and phantom sensations
in close to half. Originally thought to be
rare, phantom limb pain is now recognized to
occur in between 60% and 80% of limb
amputees. Phantom limb pain must be distinguished
from phantom sensations, which occur
in over 90% of patients. Vascular conditions
account for over 80% of limb amputations in
the United States. However, trauma is responsible
for approximately 75% of upper extremity
amputations. Most researchers have found
a statistically significant association between
phantom limb pain and persistent stump pain.
Although earlier studies found a correlation
between preamputation pain and phantom
limb pain, more recent studies have not confirmed
this relationship. It is widely held that
phantom pain diminishes with time and eventually
fades away. Though described, phantom
pain associated with congenital absence of a
limb is rare. Phantom pain is generally worse in
the distal part of a limb. Most phantoms shrink
with time, with the most distal aspect of a limb
being the last to disappear. This is known as
“telescoping,” and occurs in approximately
half of all limb amputees. Archaeological
records demonstrate that purposeful amputations
have been practiced since Neolithic times.
The concept of “phantom pain” has been recognized
for hundreds, if not thousands, of
years. In the 16th century, the French military
surgeon Ambrose Paré outlined clear distinctions
between phantom limb pain, phantom
sensation, and stump pain. The term “phantom
pain” was coined by Weir Mitchell in the
American Civil War. A few years earlier,
Mitchell used the word “causalgia” to describe
the characteristic autonomic changes found in
the extremities of soldiers who suffered major
nerve damage.


277. Which of the following statements regarding
the assessment of pain in pediatric patients is
(A) Palmar sweating and reduced transcutaneous
oxygen concentrations are indicative
of pain
(B) In a hospitalized 2-year-old child, crying
and increased vitals signs are likely to
indicate chronic pain
(C) The FACES scale and Charleston Pain
Pictures provide accurate assessments
of pain in preschool children
(D) The COMFORT scale and facial action
coding system (FACS) are pain instruments
used in young children that are
based predominantly on facial actions
(E) Visual analogue and numerical rating
scales are inappropriate pain indices for
most adolescents

277. (A) Palmar sweating and reduced transcutaneous
oxygen concentration are indicative of,
though not specific for, acute pain. In a young
child, crying and increased vital signs (eg. heart
rate, respiratory rate, and blood pressure) are
associated with distress, which includes but is
not limited to pain. Other factors that may
cause these signs include separation anxiety,
hunger, and fear. Unlike acute pain, chronic
pain is usually not associated with elevated
vital signs. The FACES scale and Charleston
Pain Pictures are designed to provide assessments
of pain in school aged, not preschool
children. The FACS and COMFORT scale are
used to assess pain in infants and young children.
The FACS is a comprehensive coding system based on a wide range of facial actions.
The COMFORT scale is an eight-item scale
designed to measure distress (including pain)
that includes alertness, calmness, respiratory
response, physical movement, blood pressure,
muscle tone, and facial tension. Pain scales
used in adults such as verbal pain scores,
numerical rating scales, and visual analogue
scales provide accurate assessments of pain in
most adolescents.


278. Which of the following statements is not correct
regarding herpes varicella zoster?
(A) The most common presentation of acute
herpes zoster (AHZ) is pain and a vesicular
rash in the midthoracic dermatomes
(B) The polymerase chain reaction (PCR) is
the most common means to diagnose
(C) The incidence of both AHZ and postherpetic
neuralgia increases with age
(D) There is no generally accepted time
period from the onset of AHZ to when a
diagnosis of postherpetic neuralgia is
(E) AHZ involving the lumbosacral
dermatomes may be misdiagnosed as a
herniated disc

278. (B) The most common way to diagnose AHZ is
clinically. In a small percentage of patients,
AHZ may occur without a rash, a condition
known as “zoster sine herpete” (zoster without
rash). The PCR is often used to aid in the diagnosis
of this condition. In descending order,
the most common sites for AHZ are the
midthoracic dermatomes, the ophthalmic division
of the trigeminal nerve, and the cervical
region. The incidence of both AHZ and postherpetic
neuralgia increases with age. Other
risk factors for AHZ include HIV infection and
transplant surgery, which is likely because of
the resultant immunosuppression. There is no
standard time period after which persistent
pain from AHZ is diagnoses as postherpetic
neuralgia. Postherpetic neuralgia has been variably
defined as the persistence of sensory
symptoms 1 month, 6 weeks, 2 months, 3 months,
and 6 months after herpes zoster. AHZ affects
the lumbosacral dermatomes in between 5%
and 15% of patients. Lumbosacral AHZ may be
misdiagnosed as a herniated disc


279. Which of the following statements regarding
electrophysiologic testing is true?
(A) Nerve conduction velocities are more
likely to decrease in conditions such as
alcoholic and diabetic neuropathy that
are characterized by Wallerian degeneration
than in demyelinating neuropathies
such as Guillain-Barré
(B) EMG can provide information about the
type, extent and timing of injuries to
motor units and individual muscle
(C) The H reflex can aid in the evaluation of
brachial plexus injuries
(D) The F response is used to diagnose pure
sensory neuropathies
(E) EMG can readily identify processes
causing muscle denervation (neuropathies),
but is incapable of identifying

279. (B) EMG provides a wealth of information
about the integrity, function, and innervation of
motor units and (using special techniques) individual
muscle fibers. Serial EMG examinations
permit monitoring of recovery or disease progression.
A normal EMG indicates the absence
of motor unit involvement. In neuropathies
characterized by Wallerian degeneration, nerve
conduction velocities range from low normal to
mildly slow. In contrast, demyelinating neuropathies
of the acute and chronic inflammatory
types produce segmental demyelination,
which markedly slows conduction velocities.
The H wave is the electrical representation of the
tendon reflex circuit. In adults, it is only obtainable
in the lower reflexes. It is most prominent
during stimulation of the tibial nerve, being
particularly helpful in the diagnosis of S1
radiculopathy and predominantly sensory
polyneuropathies. The F wave is a late response
that is evoked by supramaximal stimulation of
a motor nerve. It occurs when a small percentage
of the stimulated motor neurons “rebound.”
The initial response to stimulation of a motor
nerve is the M wave. Unlike H waves, F waves
are not true reflexes.


280. Which of the following statements is true about
quantitative sensory testing (QST)?
(A) QST can be used to pinpoint which
nerve is injured and where along its
path the lesion lies
(B) Thermal sensation is used to measure
the integrity of large, myelinated nerve
(C) A beta function can be evaluated using
either a tuning fork or von Frey hair
(D) QST can be used to evaluate the function
of all different types of nerve fibers
(E) An advantage of QST is that it can accurately
assess function in uncooperative
or incapacitated patients

280. (C) Large, myelinated nerves are more vulnerable
to injury than small neurons. The function
of large, myelinated A-β function can be
measured using both vibratory thresholds and
von Frey filaments. QST is used to evaluate the
function of individual nerve fibers. It is not
useful in determining which nerve is injured
and where along its path the injury lies. Both
cold and hot thermal sensations are used to
measure the function of small myelinated (A-δ)
and unmyelinated C fibers. QST cannot be
used to assess B (preganglionic autonomic) and
A-γ (muscle spindle efferent) function. Adownside
of QST is that its accuracy is dependent on
the cooperation and reliability of the patient.


281. A 38-year-old construction worker presents to
you with complaints of right lower extremity
pain for the last 8 months. Pain radiates from
the lower back to the outer aspect of the right
leg and goes down to the dorsum of the right
foot. The patient reports a problem with walking
and on examination reveals an antalgic gait
and inability to do heel-walking on right,
though toe-walking is not affected. Strength is
5/5 in all muscle groups except dorsi-flexion of
the right ankle which is 4/5 and strength testing
for extensor hallucis longus reveals 4/5
strength. Deep tendon reflexes are 2+ at both
knees and both ankles. Sensory testing reveals
mildly reduced sensation to light touch and
pinprick on the dorsum of the right foot when
compared to the left foot. This patient most
likely has
(A) right piriformis syndrome
(B) right L4 radiculopathy
(C) right L5 radiculopathy
(D) right S1 radiculopathy
(E) facet arthritis

281. (C) Lumbar radiculopathy most often results
from disc herniation. Depending on the level of
herniated discs radiculopathy may affect specific
nerve roots. Disc herniation at L4-5 and
L5-S1 is most likely caused by mobility of the
segment. A herniated disc may compromise
the nerve root at the same level if displaced
laterally in the recess or in the foramen (L4-5
disc affecting L4 nerve root), or it may effect the
traversing nerve root to the level below (L4-5
disc affecting L5 nerve root). L5 radiculopathy
results in pain, sensory, and motor changes in
L5 dermatomal distribution. Pain is usually
described as shooting or occasionally aching
and burning sensation on the outside of leg
radiating to the dorsum of foot. Sensory testing
may also reveal a decrease in light-touch and
pinprick sensation in the same distribution.
L5 radiculopathy also may result in weakness
in the extensor hallucis longus and thus heel
walking. Deep tendon reflexes may be spared
in the lower extremity.


282. A46-year-old female with past medical history
of depression, anxiety, irritable bowl syndrome,
and asthma is referred to you for evaluation of
her lower back pain. History reveals onset of
generalized pain that started after she was
involved in a car accident 4 years ago. Physical
examination reveals nonfocal neurologic
examination. Musculoskeletal examination
reveals multiple areas of hypersensitivity. The
patient reports marked pain with moderate
digital pressure at base of skull, her neck, front
of her chest, her elbows as well as her lower
back, and bilateral lower extremities. The
patients MRI scan of the lumbar spine reveals
preserved disc height, no facet arthritis and
minimal disc bulge at L4-5 without any spinal
or foraminal stenosis. This patient most
likely has
(A) fibromyalgia syndrome
(B) discogenic pain
(C) myofascial pain disorder
(D) somatoform disorder
(E) opioid hyperalgesia

282. (A) Fibromyalgia syndrome is a common pain
condition, estimated to occur in 2.4% of the
general population. The syndrome is characterized
by widespread musculoskeletal pain,
sleep disturbance, psychologic distress, and
comorbidity with other pain syndromes [eg,
irritable bowel syndrome (IBS), interstitial cystitis,
and the female urethral syndrome], which
have considerable impact on the everyday life
of patients. Fibromyalgia syndrome occurs predominantly
in women and demonstrates familial
aggregation. Since 1990, the diagnosis of
fibromyalgia syndrome has been based on criteria
of the American College of Rheumatology
(ACR). A key dimension of the ACR criteria is
the concept of tender points, 18 specific points
on the body surface at which digital palpation
elicits pain (11/18 “positive” tender points fulfills
an fibromyalgia criteria).
It is not uncommon for patients to have
other pain pathologies in addition to fibromyalgia.
However a complete clinical picture should
be viewed before consideration of treatment
options especially if it involves interventional
procedures. Patient describes above most likely
has fibromyalgia as evidenced by the presence
of tender points. A negative physical examination
except for tender points and hypersensitivity
argues against other listed options.


283. A25-year-old, healthy female volleyball player
has developed severe pain in right hand. This
pain started while playing volleyball and after
a reported wrist sprain. One month after the
initial injury and despite conservative care with
nonsteroidal anti-inflammatory drugs (NSAIDs),
muscle relaxants, and hand splint to avoid any
movement related pain, the patient complains
of even worse burning pain. Pain is worse with
light touch, even blowing air or rubbing of
clothes trigger unbearable pain. The patient
also reports her right hand to be cold and often
wet because of localized sweating. On examination
the patient has a markedly swollen, redappearing
hand. Patient is unable to make a
fist with her fingers and measurement of temperature
reveals a 7°C lower temperature compared
to opposite extremity. Which of the
following is the most likely diagnosis?
(B) CRPS II (causalgia)
(C) Peripheral vascular disease
(D) Deep venous thrombosis of upper
(E) Median neuralgia

283. (A) Following is the diagnostic criteria for
1. The presence of an initiating noxious event
or a cause of immobilization.
2. Continuing pain, allodynia, or hyperalgesia
with which the pain is disproportionate
to any inciting event.
3. Evidence at some time of edema, changes
in skin blood flow, or abnormal sudomotor
activity in the region of the pain.
4. This diagnosis is excluded by the existence
of condition that otherwise would account
for the degree of pain and dysfunction.
The patient in the question meets all the
criteria for diagnosis of CRPS I (RSD). CRPS II
(causalgia) by definition has a known injury to
a major nerve. Vascular etiology though possible
after trauma, is unlikely to give symptoms
of allodynia as well as sudomotor changes.
Median neuralgia would result in a similar
clinical pain picture but only hand discomfort
would be expected to be confined only to the
distribution of median nerve.


284. A 38-year-old man developed complete T4
spinal cord injury after a motorcycle accident.
Two months after the injury the patient continues
to complain of severe radiating pain to the front of chest just above nipple line. The pain is
worse with light touching and improves with
movement restriction and use of morphine on as
needed basis. This patient most likely has
(A) central dysesthesia syndrome
(B) syringomyelia
(C) transitional zone pain
(D) myofascial pain
(E) autonomic dysreflexia

284. (C) Spinal cord injury may result in various
types of pain. To provide the most effective
treatment—understanding the mechanism of
pain is very important. Taxonomy of spinal
cord injury pain may be divided into neuropathic
or nociceptive pain. The patient in question
appears to have most likely nerve root
impingement at T4-5, level of his spinal cord
injury, resulting in severe T4 neuralgic pain
radiating towards the front of chest wall.


285. After a car accident 5 days ago, a 42-year-old
engineer reports severe neck and midback
pain. The patient was rear ended while stopped
at a traffic light by a pickup truck. The patient
reports severe pain in neck that radiates down
to both shoulders and upper arm as well as to
the midback region. The pain is a severe stabbing
and aching sensation that is markedly
exaggerated by movement of neck. Examination
reveals otherwise intact neurologic system,
5/5 strength, and intact deep tendon reflexes
without any sensory deficit. Imaging studies
are essentially normal except for straightening
of cervical lordosis. The patient most
likely has
(A) bilateral C5 radiculopathy
(B) myofascial pain
(C) fibromyalgia
(D) thoracic outlet syndrome
(E) malingering

285. (B) Myofascial pain may result after a sudden
acceleration-deceleration insult. Neck muscles
may reflexly go into spasm. It may also result
in straightening of cervical lordosis secondary
to spasm of posterior supporting neck muscles.
Myofascial pain from cervical neck muscle may
radiate between shoulder blades as well into
the upper extremity. Negative imaging studies
are essential to rule out traumatic disc herniation
or fracture. Treatment includes nonsteroidals,
muscle relaxants, and physical therapy.
In a small percentage of patients, if pain doesn’t
resolve trigger point injections or cervical
medial branch blocks may provide help with
continuing physical therapy.


286. A 64-year-old female with a history of coronary
artery disease, peripheral vascular disease,
and type 1 diabetes mellitus, controlled
with insulin, presents to your pain clinic with
gradually worsening bilateral leg and feet pain.
The patient reports a history of a fall approximately
5 years ago which resulted in severe
back and leg pain. That pain resolved, however,
the patient started developing numbness
and tingling in both legs and feet. On examination
the patient reveals otherwise normal
appearing legs and feet, patient does have a
nonhealing ulcer on her right great toe.
Neurologic testing reveals bilateral 5/5 muscle
strength and 2+ patellar and ankle reflexes.
Sensory testing reveals intact proprioception
but reduced sensation to light touch and
pinprick. The patient also reported marked
sensitivity to light touch. This patient most
likely has
(B) peripheral vascular disease
(C) diabetic polyneuropathy
(D) lumbar spondylosis
(E) central pain

286. (C) In type 1 diabetes mellitus, distal polyneuropathy
typically occurs after many years of
chronic prolonged hyperglycemia. Conversely,
in type 2, it may present after only a few years
of poor glycemic control. Occasionally, in type 2,
diabetic neuropathy is found at the time of
diagnosis (or even predating diagnosis).
Diabetic neuropathy can manifest with a
wide variety of sensory, motor, and autonomic
symptoms. Sensory symptoms may be negative
or positive, diffuse or focal. Negative sensory
symptoms include numbness; “deadness”; feeling
of wearing gloves or walking on stilts; loss
of balance, especially with the eyes closed; and
painless injuries. Positive symptoms include
burning, pricking pain, electric shocklike feelings,
tightness, and hypersensitivity to touch. Motor symptoms can cause distal, proximal,
or focal weakness. Autonomic symptoms may
be sudomotor, pupillary, cardiovascular, urinary,
GI, and sexual.
A generally accepted classification of diabetic
neuropathies divides them broadly into
symmetric and asymmetric neuropathies.
Symmetric polyneuropathies involve multiple
nerves diffusely and symmetrically and are
the most common form. The patient in question
appears to have symmetrical small and
large fiber neuropathy resulting in pain in
both legs and feet, and decreased light-touch
sensation as well as allodynia.


287. A32-year-old female develops severe stabbing,
“like an ice pick,” pain at the base of tongue
after an infratemporal neurosurgic procedure.
Pain comes in paroxysms and last a few seconds
and is triggered by swallowing, yawning,
and coughing. This patient most likely has
(A) trigeminal neuralgia
(B) geniculate neuralgia
(C) glossopharyngeal neuralgia
(D) migraine with atypical aura
(E) cluster headache

287. (C) Glossopharyngeal neuralgia is a disorder
characterized by intense pain in the tonsils,
middle ear, and back of the tongue. The pain
can be intermittent or relatively persistent.
Swallowing, chewing, talking, sneezing, or
eating spicy foods may trigger the disorder. It
is often the result of compression of the 9th
nerve (glossopharyngeal) or 10th nerve (vagus),
but in some cases, no cause is evident.
Skull base surgery or surgeries in the
infratemporal region may result in damage
or irritation of glossopharyngeal nerve.
Conservative treatment includes using anticonvulsants.
In refractory cases glossopharyngeal
nerve block may be helpful. Radiofrequency
lesioning or neurolytic treatment should be
reserved for resistant cases or ones associated
with head and neck cancer. Surgical decompression
should be reserved for nonresponders
and resistant cases.


288. A38-year-old patient care technician while lifting
a 400 lb patient heard a pop in his back. The
patient developed severe back pain with radiation
to the right leg. Patient described the pain
as stabbing back pain with electrical sensations
down the back of the right leg all the way to the
sole of the right foot. On examination the
patient appeared very uncomfortable, sitting
in a wheel chair. Straight leg raise and cross
straight leg raise test was positive. Muscle
strength was 5/5 in all muscle groups except
plantar flexion at right ankle which was 4/5.
Deep tendon reflexes were intact at the patella
bilaterally; however, the reflex at the right ankle
is diminished compared to the left ankle. The
patient most likely has a herniated disc at
(A) L4-L5 resulting in L4 nerve root
(B) L4-L5 resulting in L5 nerve root
(C) L5-S1 resulting in L5 nerve root
(D) L5-S1 resulting in S1 nerve root
(E) L1-L2 resulting in compression of cauda

288. (D) Lumbar radiculopathy most often results
from disc herniation. Depending on the level
and “direction” of herniated discs a resultant
radiculopathy may affect specific nerve roots.
Disc herniation at L5-S1 is most likely a result
of mobility of the segment. A herniated disc
may compromise the nerve root at the same
level if displaced laterally in the recess or in the
foramen (L5-S1 disc affecting L5 nerve root), or
it may affect the traversing nerve root to the
level below (L5-S1 disc affecting S1 nerve root).
S1 radiculopathy results in pain, sensory, and
motor changes in S1 dermatomal distribution.
Pain is usually described as shooting or
occasionally as an aching and burning sensation
on the back of thigh radiating to the plantar
aspect (sole) of foot. Sensory testing may
also reveal a decrease in light-touch and pinprick
sensation in the same distribution. S1
radiculopathy also may result in weakness in
Plantar flexion and thus toe walking. Most
often with significant S1 nerve root compression,
ankle reflex is diminished. Examination
also may reveal positive straight leg raise and
cross straight leg raise test (reproduction of
radiating pain in lower extremity by raising
the opposite extremity).


289. A48-year-old patient after a gunshot wound to
the upper chest develops a partial cord transection
involving the right spinothalamic tract
at T2 level. This patient is most likely to develop
loss of pain and temperature sensation:
(A) At the level of the transection
(B) Below and on right side from the level
of transection
(C) Below and on left side from the level of
(D) Patient is not likely to develop central
dysesthetic pain
(E) Below and bilateral lower extremity

289. (C) The spinal cord is organized into a series of
tracts or neuropathways that carry motor
(descending) and sensory (ascending) information.
These tracts are organized anatomically
within the spinal cord. The corticospinal
tracts are descending motor pathways located
anteriorly within the spinal cord. Axons extend
from the cerebral cortex in the brain as far as
the corresponding segment, where they form
synapses with motor neurons in the anterior
(ventral) horn. They decussate (cross over) in
the medulla prior to entering the spinal cord.
The dorsal columns are ascending sensory
tracts that transmit light-touch, proprioception,
and vibration information to the sensory
cortex. They do not decussate until they reach
the medulla. The lateral spinothalamic tracts
transmit pain and temperature sensation.
These tracts usually decussate within three
segments of their origin as they ascend. The
anterior spinothalamic tract transmits light
touch. Autonomic function traverses within
the anterior anteromedial tract. Sympathetic
nervous system fibers exit the spinal cord
between C7 and L1, while parasympathetic
system pathways exit between S2 and S4.
Injury to the corticospinal tract or dorsal
columns, respectively, results in ipsilateral
paralysis or loss of sensation of light touch,
proprioception, and vibration. Unlike injuries
of the other tracts, injury to the lateral
spinothalamic tract causes contralateral loss
of pain and temperature sensation two to three
segments below the level of injury. Because
the anterior spinothalamic tract also transmits
light-touch information, injury to the dorsal columns may result in complete loss of vibration
sensation and proprioception but only
partial loss of light-touch sensation. Anterior
cord injury causes paralysis and incomplete
loss of light-touch sensation.


290. A38-year-old police officer reports continuous
neck pain lasting past 6 months. The patient
recalls lifting and carrying heavy boxes while
moving his house and reports some neck pain
at that time. Pain has gradually worsened over
the past 6 months and now patient reports
heaviness and occasional weakness in his right
hand. The patient often feels numbness in right
index finger as well. On examination, the
patient has 5/5 strength in all muscle groups
except mild weakness in flexors of the right
elbow. Light-touch sensation is intact in all
dermatomes, however, the patient reports
increased sensation to light touch in the radial
aspect of the right forearm. Deep tendon
reflexes are intact bilaterally except for right
brachioradialis reflex which is 1+ compared to
left. This patient most likely has
(A) right C5 radiculopathy
(B) right C6 radiculopathy
(C) right C7 radiculopathy
(D) right C8 radiculopathy
(E) cervical facet arthritis with referred pain

290. (B) Patients with a C6 radiculopathy should
have pain in the neck, shoulder, lateral arm,
radial forearm, dorsum of hand, and tips of
thumb, index, and long finger. Distribution of
pain is less extensive and more proximal,
whereas paresthesias predominate distally. In
some individuals, a C6 lesion will manifest as
a depressed or absent biceps reflex; in others,
an abnormal brachioradialis or wrist extensor
reflex can be found. Elbow flexion will be
weak, and the patient will be unable to
supinate the forearm against resistance with
the elbow held in extension. Conservative treatment
includes physical therapy, traction, and
analgesics. If pain persists, cervical epidural
steroid injection may provide relief from pain
and aid in physical therapy. However, if symptoms
persist or weakness/numbness doesn’t
improve surgical decompression with or without
anterior fusion may be considered


291. A 42-year-old man underwent a celiac plexus
block procedure with 20 mL of 50% alcohol.
All of the following listed conditions are complications
of this intervention EXCEPT
(A) genitofemoral neuralgia
(B) hypertension
(C) diarrhea
(D) paralysis
(E) infection

291. (B) Celiac plexus block is both a diagnostic and
therapeutic tool to help in managing upper
abdominal pain arising from viscera. Pancreatic
cancer is the leading diagnosis for neurolytic
celiac plexus block; other conditions may
include visceral pain arising from malignancies
of liver or GI tract.
The procedure is performed either under
fluoroscopic guidance or CT scan, though
blind approaches have also been described.
Both single transaortic as well bilateral needle
approaches have been described. The fluoroscopic
image in question demonstrates a single
needle transaortic celiac plexus block.
Complications include diarrhea, hypotension,
genitofemoral neuralgia, infection, bleeding,
damage to surrounding structures and rarely
paralysis. All complications mentioned above
may occur except hypertension


292. Atwo-needle lumbar sympathetic plexus block
at L2 and L3 when performed appropriately
may help in the diagnosis of
(A) sympathetically mediated pain
(B) lumbar discogenic pain
(C) lumbar radiculopathy
(D) diabetic neuropathy
(E) facet arthritis

292. (A)Aproper diagnostic test requires a preblock
patient evaluation (with special attention to the
ipsilateral lower extremity pain, temperature,
and condition), a local anesthetic injection
using appropriate volume to avoid spread to
adjacent nerves and a postblock evaluation of
subjective improvement in pain score as well
an objective increase in the temperature of the
involved extremity is crucial. Significant
improvement in pain scores with increase in
temperature of the involved extremity points
toward a positive diagnosis of sympathetically
mediated pain.
Discography is performed for diagnosis of
lumbar discogenic pain. Whereas diabetic neuropathy
may result in sympathetically mediated
pain, it is a mixed somatic polyneuropathy and
diagnosis is a clinical one. Lumbar selective
nerve root block and facet joint injections may
aid in the diagnosis of lumbar radiculopathy
and facet arthritis resulting in pain.


293. A patient who received 1 cc of 0.25% bupivacaine
after negative aspiration following a cervical
selective nerve root injection became
agitated and then developed generalized tonicclonic
movements. Which of the following is
the most likely explanation?
(A) High spinal anesthetic from accidental
intrathecal injection
(B) Anxiety attack from pain during
(C) Vertebral artery injection of local
(D) Injection into spinal cord
(E) Hypoxia

293. (C) Cervical selective nerve root injection may
be indicated for diagnosis and treatment of cervical
radiculopathy. Complication other than
infection, bleeding, and nerve damage, include
intravascular uptake into vertebral artery or
radicular arteries resulting in seizure, stroke, or
paraplegia. Intraspinal spread into epidural
or intrathecal spread is also possible resulting
in high spinal anesthetic. Damage to spinal
cord has also been reported with injection into
the spinal cord. Considering the life-threatening
complications, cervical selective nerve root
block should only be performed by physicians
well versed in this technique.


294. Medial branch nerve blocks may aid in the
diagnosis of
(A) facet arthritis
(B) sympathetically mediated pain
(C) spinal nerve irritation
(D) sciatica
(E) myofascial pain

294. (A) Medial branches of the dorsal ramus provide
innervations to the respective facet joint as
well to the joint below. A diagnostic medial
branch block with local anesthetic performed at
appropriate levels (eg, L3 and L4 for L4-5 facet
joint) may provide diagnostic and prognostic
information to help with pain associated with
facet arthritis.
If pain is considerably albeit transiently
improved after diagnostic medial branch blocks,
a radiofrequency ablative procedure may be
considered to provide longer lasting pain relief.


295. Which of the following is the most likely side
effect of a SI joint injection?
(A) Perforation of bladder
(B) Left lower extremity weakness
(C) Stroke
(D) High spinal resulting in cardiorespiratory
(E) Injury to pudendal nerve

295. (B) SI joint injection is performed for both diagnostic
and therapeutic reasons in patient complaining
of SI joint pain. After a therapeutic injection with 5 to 10 mL of local anesthetic; it is
possible that the local anesthetic may spill inferiorly
and anteriorly and anesthetize sciatic
nerve resulting in leg weakness. Patients may
be warned about this, if observed afterward,
and should be accompanied by a reasonable
adult to avoid any falls and resultant injuries


296. The potential complications of the vertebroplasty
procedure include all EXCEPT
(A) spinal cord compression
(B) venous embolism
(C) pedicle fracture
(D) cement leak in soft tissue
(E) bowl perforation

296. (E) Vertebroplasty is an advanced procedure
that is performed to stabilize recently fractured
vertebral bodies resulting in excruciating back
pain. Performed properly and by trained physicians,
vertebroplasty is a safe procedure.
However, complications, though rare, are possible
and uncompromising. These may include
infection; bleeding; pulmonary embolus;
damage to pedicles, spinal cord, or surrounding
structures; allergic reactions to injectate;
and cement leak into soft tissue or in spinal
canal resulting in spinal cord compression.


297. A 70-year-old man reports severe cramps and
“charley horse” sensation in both legs when
walking more than one block. Resting usually
helps in relieving pain. On examination patient
reveals an intact neurologic examination without
any sensory or motor deficit. Lower
extremity examination reveals normal appearance,
and no vascular insufficiency. Ankle
brachial index performed 1 month ago is unremarkable.
Which of the following is the most
likely diagnosis?
(A) Neurogenic claudication
(B) Vascular claudication
(C) Diabetic peripheral neuropathy
(D) Amyloid neuropathy
(E) Fibromyalgia

297. (A) Spinal stenosis may result from narrowing
of the spinal canal secondary to hypertrophy of
ligamentum flavum, articular processes and
anteriorly from degenerative bulging discs.
Stenosis may result in a classical presentation of
neurogenic claudication with pain in lower legs
or feelings of “charley horse” that come with
walking an unpredictable distance and is
relieved by resting or sitting down. In contrast
to vascular claudication, the patient may report
some back pain as well. In addition, pain is not
predictably elicited after a certain walking distance
because it is relative extension of the
lumbar segments that results in worsening
stenosis and neurogenic claudication rather
than ischemia. Pain is relieved in neurogenic
claudication by assuming a flexion posture
(bending forward).
Treatment includes posture education,
education and improvement of body mechanics,
and physical therapy. Epidural steroid
injection series may provide pain relief in
some patients. If pain or significant limitation
in activity persists a decompressive laminectomy
may be considered.


298. A32-year-old healthy female presents with a 2-
month history of gradually worsening right
lower extremity pain. The pain is sharp shooting
in character and radiates down the right leg
all the way to the right foot. On examination,
patient has 5/5 muscle strength in all muscle
groups except plantar flexors of the right ankle.
The patient is unable to stand on her toes. There
is no sensory deficit. Flexion, adduction, and
internal rotation of the right hip results in
reproduction of the symptoms. MRI of lumbar
spine is normal with no evidence of herniated
discs. This patient most likely has
(A) right S1 radiculopathy
(B) piriformis syndrome
(C) SI arthritis
(D) somatization disorder
(E) discogenic pain

298. (B) The piriformis is a sausage-shaped muscle
which originates from the anterior surface of
the lateral sacrum and attaches to the greater
trochanter. In most individuals the sciatic nerve
lies anterior to the muscle belly. Spasm of the
muscle may result in irritation of the sciatic
nerve and resultant sciatica. The patient may
report localized tenderness in the lower part of
the buttock. In addition, if patients have irritation
of sciatic nerve, they may also report
symptoms suggestive of sciatica which may
easily be confused with lumbar radiculopathy.
However, flexion, adduction, and internal rotation
of the thigh results in tightening of piriformis
muscle which may reproduce pain
symptoms. MRI should be carefully evaluated
to rule out any radicular component.
Treatments include muscle relaxants and
physical therapy to break muscle spasm. If
pain persists or if the patient is unable to continue
with physical therapy, piriformis muscle
injection may aid in treatment.


299. A 25-year-old construction worker, 8 months
after a fall from a ladder, is unable to walk without
assistance. However, worker compensations
lawyers have provided video evidence of the
patient being able to walk and also able to run
with his dog. Which of the following is the most
likely diagnosis?
(A) Hypochondriasis
(B) Factitious disorder
(C) Malingering
(D) Conversion disorder
(E) Somatization disorder

299. (C) There can be physical and psychologic
symptoms of malingering and factitious disorder.
In these conditions the patient willfully
produces or feigns symptoms of illness or
injury. In the factitious disorder the goal of the
behavior is the patient’s need to be in sick
role—a need not understood by the patient.
Placing blood into urine and pretending to
have posttraumatic stress disorder are examples.
There is no apparent external goal such as
to obtain money or drugs. It is always a psychiatric
illness. This contrast with malingering,
in which there is a clearly defined external goal.
Malingering is not a psychiatric illness.
Diagnosis of hypochondriasis require atleast
6 month of preoccupation with the fear or
belief that one has a serious disease, based on
the interpretation of physical signs or sensations
as evidence of illness. Somatization disorder
is characterized by an extensive history
of multiple somatic symptoms that are psychologic
in nature. In addition to many physical
complaints or a belief that one is sickly, the
criteria require at least 13 symptoms from a list
of 41. The symptom list includes 6 GI symptoms,
7 pain symptoms, 4 cardiopulmonary
symptoms, 12 conversion/pseudoneurologic
symptoms, 4 sexual symptoms, and 4 female
reproductive symptoms. Conversion disorders
are patients presenting with physical symptoms without any anatomic or pathophysiologic
basis (pseudoneurologic symptoms;
pseudoparalysis, pseudoseizure etc).


300. A 43-year-old gentleman has developed left
groin pain 6 months after an inguinal hernia
repair. The patient reports pain to be severe
stabbing pain in the left groin radiating down
to the left testicle. On examination, the patient
has a well-healed incision and marked cutaneous
allodynia and hyperalgesia. This patient
most likely has
(A) ilioinguinal neuralgia
(B) mesh infection
(C) recurrent hernia
(D) wound dehiscence
(E) incarceration

300. (A) Ilioinguinal neuralgia may develop after
any surgery in inguinal area resulting in
damage to the ilioinguinal nerve. Pain may
start immediately after the surgery or may start
after a reasonable period of healing has passed.
Wound infection, recurrent hernia, and mesh
infection should be ruled out to avoid any correctable
causes of ilioinguinal pain. Pain is usually
described as sharp, electrical sensation or
sometimes as constant burning sensations in
the groin area with occasional radiation into
the testicles. Pain is exacerbated by light touch
or rubbing of clothes. Treatment includes anticonvulsants
and other adjuvant medications. If
pain persists, local anesthetic diagnostic and
therapeutic block as well as other treatment
approaches may be warranted. Radiofrequency
ablation, peripheral nerve stimulation, neurectomy,
and repeat surgery should be reserved
for resistant cases.


301. Which of the following is the most common
complication from the celiac plexus block?
(A) Hypotension
(B) Seizure
(C) Diarrhea
(D) Hematoma
(E) Subarachnoid injection

301. (A)
A. Hypotension from sympathetic blockade
is the most common complication. It is
important to optimally prehydrate these
patients prior to the onset of the block.
B. Seizure results from intravascular injection
of large volume of local anesthetic stressing
the need to confirm negative aspiration
prior to injecting the solution.
C. Diarrhea ensues as a result of sympathetic
blockade and unopposed parasympathetic
D. Retroperitoneal hematoma is a rare complication
of celiac plexus block.
E. Subarachnoid injection is the most serious
and very rare complication celiac block.


302. A patient with history of three lumbar spinal
fusions from an injury while working in a
halfway home who is responsive to MS Contin
(sustained-release morphine) 30 mg, three
times a day and Norco (hydrocodone 5 mg
with acetaminophen 325 mg) eight tablets per
day with adequate analgesia and improved
functionality, but limited activity secondary to
side effects, receives an intrathecal opioid
pump trial after been cleared by his psychologist.
After confirmation of appropriate placement
of the catheter under fluoroscopy, he is
put on 0.5 mg/d of intrathecal morphine and
gradually escalated up to 10 mg/d because of
inadequate analgesia. Twelve hours after the
procedure, he complains of nausea, headache,
and sensation of “skin peeling off his body.”
Which of the following is the best course of
action in this case?
(A) Increase the intrathecal morphine until
pain relief and resolution of symptoms
(B) CT scan of his spine to confirm correct
placement of the catheter
(C) Removal of the catheter and institution
of oral opioids
(D) Urine toxicology
(E) Consultation with a spine surgeon

302. (D)
A. Increase in the intrathecal morphine dose
is warranted in some situations when a
patient demonstrates signs and symptoms
consistent with withdrawal or has inadequate
analgesia. In that case it is important
to carefully evaluate the equianalgesic
dose accounting for change in route or
incomplete cross tolerance with change of
drugs. In this case, considering the oral to
intrathecal conversion is 300 to 1, the patient
has been escalated to 10 mg of intrathecal
morphine a day; it seems unlikely that his
symptoms would be because of opioid
withdrawal provided his catheter is in the
correct position as had been confirmed
under fluoroscopy in this case.
B. CT scan can be done to confirm the correct
placement of the catheter if necessary; however
it is highly unlikely that the catheter
would move in a short time in a sedentary
postsurgical patient.
C. Removal of catheter followed by reimplantation
is a possibility if indeed catheter is
determined to be malpositioned. It seems
rather premature to pursue such option at
this time.
D. Urine toxicology seems like a more viable
option considering this patient’s association
with a half way home and the time of
onset of his symptoms approximately
12 hours after the hospitalization. Also, the
symptoms experienced although nonspecific,
point toward possible withdrawal
from a substance of abuse. It is reasonable
to order a urine/serum toxicology screen as
an initial step at this point while instituting
conservative treatment with nonopioid
analgesics and antinausea preparations.
E. Spine surgeon consultation does not seem
necessary at this point since the symptoms
experienced are not truly suggestive of spinal
hematoma, infection, or neurologic deficits
warranting acute surgical intervention.


303. Migraine headaches are directly related to
(A) estrogen increase
(B) estrogen decrease
(C) progesterone increase
(D) progesterone decrease
(E) none of the above

303. (B) The mechanism by which ovarian hormones
influence migraines remain to be determined,
but an abrupt decrease in serum
estrogen concentrations before the onset of an
attack appears to be a critical factor. Sometimes
the use of percutaneous estrogen gel applied
just before and through the menstrual cycle
may reduce the frequency of headaches.
However, in some other cases use of low-dose
estrogen oral contraceptive formulation are associated with a haphazard occurrence of
attacks during the cycle, probably because of
fluctuating estrogen levels. Therefore, it seems
prudent to have the treatment strategies aimed
toward preventing either a decrease or substantial
fluctuation in the levels of estrogen.


304. A50-year-old female comes in complaining of
sudden onset pain in bilateral lower extremities
and loss of bladder function. Her physical
examination reveals motor weakness in her left
lower extremity 3/5 compared to the right
along with diminished sensation to light touch,
pinprick, and temperature along L5 and S1 dermatomes
on the right compared to the left. Rest
of her physical, musculoskeletal, and neurologic
examination is normal. Lumbosacral x-rays
done by her primary care physician demonstrate
anterolisthesis of L5 on S1. Which of the
following is the most appropriate immediate
(A) Consult the spine surgeon
(B) Intravenous Opioids
(C) Physical therapy
(D) Reassurance and return to home with a
follow-up visit in 2 weeks if symptoms
(E) A course of oral steroids

304. (A)
A. Considering the acute onset of bladder
dysfunction and neurologic deficits on
physical examination along with the
anterolisthesis of L5 on S1, urgent evaluation
by a spine surgeon seems to be the
best immediate option of all. This patient
needs further workup and possibly even
urgent intervention by the spine surgeon
at this time.
B. While intravenous opioids can be used to
control acute pain, they by no means
should be considered adequate in managing
this situation that demands urgent surgical
C. Physical therapy may be considered in
future for this patient for physical rehabilitation
once surgical evaluation and/or
intervention has been completed. Physical
therapy for acute pain management is inappropriate
for this case considering the risk
of neurologic deficits that may ensue from
further movement of an unstable spine.
D. This condition could be a surgical emergency
and so this patient should be actively
managed in an in-patient setting.
E. Oral steroids may sometimes be beneficial
in such setting to decrease the pain and
inflammation associated with acute spine
pain, but the surgical evaluation should
take precedence over all conservative treatment
options that may delay resolution of
the spinal pathology.


305. The approaches to celiac plexus block are all
(A) retrocrural
(B) transcrural
(C) transaortic
(D) intercrural
(E) latera

305. (E) Celiac plexus or ganglia, these terms often
used interchangeably, are a dense network of
pre- and postganglionic fibers. The three
splanchnic nerves; greater, lesser, and least
synapse at the celiac ganglia.
A. Retrocrural approach is the most commonly
utilized by anesthesiologists and
considered the most traditional. The landmarks
include iliac crests, 12th rib, dorsal
midline, vertebral bodies (T12-L2), and lateral
border of the paraspinal (sacrospinalis)
B. Transcrural approach involves placement
of needle tips anterior and caudal to the
diaphragmatic crura. Advocates of this
approach believe that this approach maximizes
spread of injected solutions anterior
to the aorta where the celiac plexus is most
concentrated and this minimizes the somatic
nerve block.
C. Transaortic approach to celiac plexus has
been described under both fluoroscopic
and CT guidance. It is considered safe by
many because of the use of single fine needle
compared to two-needle posterior
approach. This approach has three distinct
advantages over the classic two-needle
approach. First, it avoids the risk of neurologic
complications related to posterior
retrocrural spread of drugs. Secondly, the
aorta provides a definitive landmark for
needle placement when radiographic
guidance is not available and thirdly,
much smaller volumes of local anesthetic
and neurolytic solutions are required to
achieve efficacy equal to or greater than
that of classic retrocrural approach.
D. Intercrural approach is a term that can technically
be applied to transaortic approach
since the needle tips are placed in front of the
diaphragmatic crura in this approach, but
more commonly this term is used to refer to
the classic anterior approach to celiac plexus
under CT or ultrasound guidance.
E. Lateral approach has not been described in


306. A 25-year-old male presents to you with leftsided
neck pain with radiation along lateral
aspect of the left arm, forearm, and thumb,
index, and middle finger. He has associated
tingling and numbness. On neurologic examination,
the sensation to pinprick is diminished
in the above mentioned distribution and brachioradialis
jerk is lost on the left compared to
intact 2+ on the right. The MRI of C-spine is
compatible with an acute cervical disc herniation.
Which of the following is the most appropriate
initial treatment?
(A) A course of oral opioids, oral steroids,
and spine surgical consultation
(B) A series of cervical epidural steroid
injections under fluoroscopy
(C) Physical therapy
(D) Spinal cord stimulation (SCS)
(E) Referral to pain psychologist for coping

306. (A)
A. The trial of oral opioids, steroids, and
urgent consultation with a spine surgeon
are the most appropriate initial steps in
management of what seems to be a case of
acute radiculopathy secondary to acute
disc herniation. Because these substantial
neurologic deficits may be reversed with
appropriate and timely decompression the surgical evaluation and course of
steroids are top priorities here.
B. Cervical epidural steroid injections can be
considered to decrease the inflammation,
but does not qualify to be “most appropriate
initial treatment.”
C. Physical therapy can be instituted further
down the road for rehabilitation.
D. SCS may be beneficial to decrease neuropathic
pain of chronic nature, but it has no
role in an acute setting of this nature.
E. Pain psychologist can prove to be very
useful in patients suffering from chronic
pain, but again has little role in acute pain
management in this setting.


307. Hoffmann sign is indicative of
(A) upper motor neuron lesion (UMNL)
(B) lower motor neuron lesion (LMNL)
(C) radiculopathy
(D) instability of cervical spine
(E) malingering

307. (A) Hoffmann sign is indicative of UMNL. In
fact, it is the upper extremity equivalent of
Babinski reflex. The examiner holds the patient’s
middle finger and briskly flicks the distal phalanx.
A positive sign is noted if the interphalageal
joint of thumb of the same hand flexes.


308. A 65-year-old male comes in complaining of
pain in between the third and the fourth toes.
The pain can be reproduced by palpation of
the pulp between metatarsal heads. There is
some relief of pain following localized administration
of local anesthetic. Which of the following
is the most likely diagnosis?
(A) Plantar fascitis
(B) Metatarsalgia
(C) Tarsal tunnel syndrome
(D) Morton neuroma
(E) Painful calcaneal spur

308. (D)
A. Plantar fascitis is an inflammation of the
tendons and the fascia of the foot as they
insert into the calcaneal periosteum. It is
typically seen in the people who stand on
hardwood floors for a prolonged period of
time. Pain is elicited with plantar compression
over the anterior calcaneus and also
may radiate along plantar fascia.
B. Metatarsalgia is characterized by pain in
the plantar surface of the metatarsal heads
caused by prolonged weight-bearing. It
can also be replicated with manual compression
over the metatarsal heads. Pain is
most commonly increased in combined
pronation and eversion.
C. The etiology and diagnosis of tarsal tunnel
syndrome is somewhat controversial. This
syndrome involves compression or inflammation
of the posterior tibial nerve that
provides sensory innervation to medial
aspect of the calcaneus, motor supply to
small lateral musculature of the foot and to
the medial and lateral plantar branches.
The symptoms are usually vague with
activity related problems. Pain along with
paresthesia, cramping, and burning is seen
in the distribution. Palpation reveals sensitivity
in the area. EMG testing can be utilized
in diagnosis of tarsal tunnel syndrome
but is controversial.
D. Morton neuroma (interdigital neuroma) is
the compression of the interdigital nerves
in between the metatarsal heads and deep
transverse metatarsal ligaments. The third
interspace between third and fourth
metatarsal is most frequently involved, it
is believed to be so because lateral plantar
nerve sends a branch to the medial plantar
nerve to form a larger third common digital
nerve making it less mobile. The condition
is usually unilateral and affects
females more commonly than men, usually
in their 50s. The most common symptom
is plantar pain that is increased by
walking or by palpation between the third
and fourth metatarsal heads.
E. Painful calcaneal spur is often seen in morbidly
obese people or those who stand or
walk excessively. Pain is increased in the
morning or after a prolonged rest and similar
to plantar fascitis except that it is more
predominant in the posterior aspect of the
plantar calcaneus.


309. Which of the following is the most common
nerve missed with the interscalene brachial
plexus nerve block?
(A) Ulnar
(B) Radial
(C) Musculocutaneous
(D) Median
(E) Axillary

309. (A) Interscalene block of brachial plexus is
especially effective for surgery of the shoulder
or upper arm, as the roots of the brachial plexus
are most easily blocked with this technique.
Ulnar nerve is most frequently spared since it
is derived from the eighth cervical nerve and
the block is placed at a more cephalic site with
this approach. This block is ideal for reduction
of a dislocated shoulder or any other type of
surgery on shoulder or upper arm.


310. A 23-year-old gymnast while performing a
double loop hears a popping sound in her left
knee. Her knee immediately swells up and is
very painful. On physical examination, tenderness
on palpation and effusion is demonstrated.
McMurray test is positive. Which of
the following is the most likely diagnosis?
(A) Baker cyst
(B) Anterior cruciate ligament tear
(C) Posterior cruciate ligament tear
(D) Torn medial meniscus
(E) Pes anserine bursitis

310. (D)
A. A baker (popliteal) cyst represents ballooning
of the synovium-lined joint capsule,
usually on the posteromedial aspect
of the knee. It is usually a secondary manifestation
of underlying condition that
causes chronic inflammation of the knee,
such as meniscal tear, knee synovitis or
intra-articular loose body. The diagnosis of
the popliteal cyst can be made by direct
palpation of the mass. Arthrography or an
MRI can verify the diagnosis and demonstrate
its communication with the joint
cavity. The cyst usually resolves with correction
of the underlying pathology.
B. Anterior cruciate ligament is the most
commonly injured knee ligament in athletes.
Injury to this ligament will result in a
bloody knee effusion that is very indicative
of this particular kind of injury. Three
tests used to diagnose anterior cruciate ligament
injury are anterior drawer test,
Lachman test, and pivot shift test.
C. Posterior cruciate ligament is usually damaged
in violent, usually high–kinetic
energy injuries. These usually occur in
combination with fractures, specifically to
the patella and hip or with other knee ligament
injuries. Injury to popliteal artery
should be evaluated in this injury with
palpation or even arteriography. The test
used to diagnose posterior cruciate ligament
injury is posterior drawer test.
D. In stance more than 60% of the body’s
weight is carried on the peripheral aspect
of the tibial plateau by meniscal fibrocartilages.
In younger persons, the meniscal
injuries usually accompany other ligament
injuries whereas in elderly, these usually
occur in isolation. When a meniscal tear is
extensive it can result in block to terminal
knee flexion or extension, commonly
described by patients as “locking of the
knee”. A torn meniscus can cause knee
swelling and pain as it irritates the joint
surface or synovium. Chronic meniscal
injuries can result in arthritic joint surface.
Joint line tenderness is found in about 50%
of these injuries. McMurray test is used to
detect tear of the meniscus that can be displaced.
It is performed by flexing and
extending the knee between 90° and 140°
of flexion. One of the examiner’s hands
rotates the tibia at the ankle while the
other hand is placed in front of the joint
line. This is followed by the extension of
knee in the rotated position. A palpable
click indicates an unstable tear of the
meniscus. The Apley grind test can help
distinguish between tear in the anterior or
posterior portion of the meniscus. MRI or
arthroscopy can also be used as diagnostic
tools to identify a meniscal lesion.
E. Pes anserine bursa lies between the medial
hamstring tendons (sartorius, gracilis, and
semitendinosus) and proximal medial
tibia. It is inferior to the joint line which
helps distinguish from the medial joint
line tenderness secondary to meniscal


311. A 35-year-old female is rear ended at 45 mph
resulting in acute neck pain that was diagnosed
to be of musculoskeletal nature in the emergency
room. On the next day, her symptoms
progress to right upper extremity pain and
weakness, both of which are exacerbated with
ipsilateral flexion of her neck and reaching
overhead. She has no neurologic deficits and
MRI of her neck shows no obvious pathology.
There is obliteration of the radial pulse with
arm extension and abduction. Which of the following
is the most likely diagnosis?
(A) Brachial plexitis
(B) Cervical degenerative disc disease
(C) Whiplash injury
(D) Pancoast tumor
(E) Thoracic outlet syndrome

311. (E)
A. Brachial plexitis is an acute disorder of that
almost always begins with unilateral diffuse
pain in the shoulder followed by
weakness in the proximal muscles. Sensory
disturbances are less pronounced than motor
deficits. The pain usually subsides after the
acute phase. Electrodiagnostic studies can
help to establish the diagnosis.
B. Cervical degenerative disc disease can result
in diffuse axial pain in the neck or radicular
pain along a particular dermatome corresponding
to the nerve root involved if associated
with a herniated nucleus pulposus.
C. Whiplash injury typically follows a highimpact
motor vehicle accident that results
in axial neck pain. It has a musculoskeletal
component to it and is frequently associated
with facet joint involvement.
D. Pancoast tumor is the tumor of the apex of
the lung that typically involves the
brachial plexus. Pain is a common presenting
symptom usually involving the lower
cervical nerve roots or trunks. CT scan or
MRI can sometimes offer valuable diagnostic
E. Thoracic outlet syndrome usually involves
impingement of subclavian vessels and
lower trunk of brachial plexus resulting in
various degrees of vascular or neurologic
compromise or both with local supraclavicular
pain. The most common etiologies are
cervical rib, hypertrophy of scalenus anticus,
costoclavicular abnormalities, but nevertheless
can result from an acute trauma.
The pain and sensory changes are usually
aggravated by any activity that extends the
brachial plexus, including carrying heavy
objects, abducting arms over the head or
with repetitive movements of the arm.
Motor weakness is seen in intrinsic muscles
of the hand. The obliteration of radial
pulse with arm extension or abduction or
traction can be present and is called Adson
or Allen test.


312. The following is true about the H reflex EXCEPT
(A) in clinical practice H reflex is limited to
calf muscles
(B) it is recorded in gastrocnemius and
soleus muscles by stimulating the posterior
tibial nerve in the popliteal fossa
(C) because of the distance the impulse
travels, the latency of the H wave is
shorter than the F wave
(D) the H reflex recorded from the soleus
muscle is primarily mediated by the
S1 nerve root
(E) H reflex is normal in L5 radiculopathy
whereas is prolonged in S1 radiculopathy

312. (C)
A. H wave responses, in adults can be obtained
in lower extremities. H wave response is an
electric equivalent of the ankle deep tendon
reflex, when the tibial nerve is stimulated.
B. The tibial nerve behind the knee in the
popliteal fossa is stimulated and the impulse
travels via afferent fibers to the spinal cord
at the S1 level. After synapse in the cord,
anterior horn cells produce a motor response
that can be recorded in gastrocnemius and
soleus muscles.
C. H waves are true reflexes, F wave is not.
Because the H wave has to travel to the
level of cord in order to produce a response,
the latency is longer compared to F wave.
D. This is correct as explained in (B).
E. Since the impulses are conducted through
S1 nerve, H reflex is typically prolonged in
S1 radiculopathy but may be normal in L5


313. The arteria radicularis magna, also known as
artery of Adamkiewicz arises from aorta, at the
following spinal levels:
(A) L4-5
(B) T9-12
(C) T5-8
(D) T11-12
(E) T5-9

313. (B) The spinal cord receives its blood supply
from three longitudinal arteries: a single anterior
spinal artery and two posterior spinal arteries.
The diameter of anterior spinal artery is
greatest at the cervical and lower thoracic levels
and narrowest at the midthoracic levels from
T3-T9. This region of the cord is considered
to be the “vulnerable zone” with respect to
circulation. The anterior spinal artery is reinforced
at a number of segmental levels by
feeder arterial branches called anterior
medullary feeder arteries. At the thoracic level,
there are a total of eight of these feeder arteries,
largest of which is called artery of Adamkiewicz
or great anterior medullary artery. This artery
typically enters the cord on the left side anywhere
from T7 to L4, but most commonly at


314. A56-year-old male who is an avid golfer comes
in with left elbow pain not relieved after antiinflammatory
medication trial, warm compress,
and physical therapy. He has not been
able to play 18 holes recently and this is making
him quite depressed. On examination, passive
flexion or extension against resistance of his
left wrist causes pain. Which of the following is
the most probable diagnosis in this patient?
(A) Posterior interosseous nerve entrapment
(B) Medial epicondylitis
(C) Lateral epicondylitis
(D) de Quervain disease
(E) Brachioradialis tendonitis

314. (C)
A. The involvement of deep radial nerve is
called posterior interosseous nerve entrapment.
The symptoms are similar to radial
tunnel syndrome including pain over the
proximal dorsal forearm, with maximum
tenderness at the site of radial tunnel that
is 4 cm distal to the lateral epicondyle over
the posterior interosseous nerve. The pain
is typically elicited by attempting to resist
extension of long finger.
B. Medial epicondylitis or golfer’s elbow
results in pain and exquisite tenderness over
medial epicondyle that is further aggravated
by flexion and pronation of the forearm
and the wrist.
C. Lateral epicondylitis or tennis elbow
involves the extensor-supinator muscle
mass, including extensor carpi radialis brevis,
extensor digitorum communis, extensor
carpi radialis longus, extensor carpi ulnaris,
and supinator. The extensor carpi radialis is
most commonly involved, mostly from
repetitive movement of the wrist involving
wrist flexion, elbow extension, and forearm
pronation. Provocative test involves grasping
or extending the wrist against resistance
or supinating the forearm when sudden and
severe pain is experienced in the area of lateral
epicondyle. The patient’s being an
“avid golfer” is a distractor here.
D. de Quervain disease or tenosynovitis of the
tendon sheath of extensor pollicis brevis and
adductor pollicis longus causes swelling and
tenderness of anatomic snuff box.
E. Brachioradialis tendonitis results in pain
in the lateral forearm, that is, region of brachioradialis
tendon, the provocative tests
described above typically do not elicit
characteristic symptoms.


315. All of these cervical pathologies are seen in
patients with rheumatoid arthritis EXCEPT
(A) subaxial subluxation
(B) cranial settling
(C) posterior-longitudinal ligament
(D) atlantoaxial subluxation
(E) instability of cervical-zygapophyseal

315. (C) Patients with cervical rheumatoid arthritis
develop neck pain exacerbated by movement,
with atlantoaxial disease producing pain in
upper cervical spine and subaxial involvement
producing pain in lower neck and clavicular
areas. Neurologic involvement is seen in more
advanced cases of spinal cord or nerve root
compromise related to deformity and soft tissue hypertrophy. Plain radiography is useful
in showing structural abnormalities and
dynamic studies including flexion extension,
oblique and open mouth frontal projections in
identifying instability. Anterior subluxation of
atlantoaxial joint is the most common form of
cervical spine derangement followed by subaxial
subluxation (between C3 and C7), lateral
subluxation, cranial settling (vertical subluxation),
and posterior subluxation. Also, the
autoimmune inflammatory changes affect the
synovium of zygapophyseal joints resulting in
laxity and subsequent instability.


316. While undergoing lumbar sympathetic block
for CRPS, patient complains of sudden onset of
sharp ipsilateral groin and genital pain on injection
of the contrast agent. Which of the following
is the most likely cause of this symptom?
(A) Trauma to L2 nerve root
(B) Trauma to genitofemoral nerve
(C) Psoas spasm
(D) Epidural injection
(E) Successful lumbar sympathetic block

316. (B)
A. Trauma to L2 nerve root may cause ipsilateral
groin pain, but is not the most likely cause.
B. The most likely cause of the symptoms
mentioned in the question is trauma to genitofemoral
nerve. In fact, it is the most common
complication associated with lumbar
sympatholysis, particularly by the lateral
approach. The incidence has been reported to
be as high as 15%, but may be as low as 4%
with a single-needle technique. Most cases
are transient and resolve with conservative
measures but others may last as long as 6
weeks. Repeat local anesthetic lumbar sympathetic
block, TENS (transcutaneous electrical
nerve stimulator) unit and intravenous
lidocaine have all been described as options
for remission of genitofemoral neuralgia.
C. Psoas spasm is also sometimes seen but it
typically produces discomfort in ipsilateral
low back.
(D) and (E) do not present as groin pain.


317. Which of the following is the most common
inherited neuropathy?
(A) Familial amyloid polyneuropathy
(B) Fabry disease
(C) Porphyric neuropathy
(D) Charcot-Marie-Tooth disease
(E) Diabetic polyneuropathy

317. (D) Painful symptoms of Charcot-Marie-Tooth
(CMT) disease have been described in the
hypertrophic or demyelinating form (CMT-1).
Pain may be described shooting, sharp, or
burning in their toes, feet, ankles, and knees.
Common presentation is in the first or second
decade with difficulties walking or running.


318. A 52-year-old man comes to your office complaining
of 11/2 years of “burning” pain in the
metatarsal areas of his left foot. Which of the
following is the most likely diagnosis?
(A) Posterior tibial neuritis
(B) Plantar fasciitis
(C) Morton neuroma
(D) Tarsal tunnel syndrome
(E) Hallux rigidus

318. (C) Morton neuroma may be considered in the
spectrum of interdigital neuritis (compression
neuropathy). It is usually between the third
and fourth toes or less often between the fourth and fifth toes. The pain tends to be experienced
more with walking and weight bearing while
wearing shoes. The pain is generally alleviated
with rest and removal of shoes. The pain may
be reproduced by exerting pressure between
the two toes implicated. Interdigital injection of
local anesthetic relieves the pain.


319. In MRI of the lumbar spine T2-weighted
(1) are generally more time-consuming to
(2) are ideal to image the anatomic detail of
end-plate reactive changes
(3) exhibit increased sensitivity to higher
water content and thus, may be useful
in imaging infectious processes or
(4) can be used in place of gadolinium-
DTPA (diethylenetriamine pentaacetic
acid) contrast in imaging of postoperative
patients to differentiate scarring
from intervertebral disc issues

319. (B) MRI, especially with T2-weighted images
(though generally more time consuming to
obtain) is useful in imaging conditions such as
osteomyelitis, discitis, spinal cord compression,
and malignancy. T1-weighted images provide
reasonably good anatomic detail in imaging of
end-plate reactive changes as well as postoperative
scarring, but gadolinium-DTPA contrast
should be used in postoperative patients
to differentiate scarring from intervertebral


320. In EMG and NCS, the H reflex
(1) is the electrical equivalent of a muscle
stretch reflex elicited by tendon tap
(2) is mostly present in the soleus muscle
but at times also can be elicited in the
forearm flexor muscles
(3) may be delayed or absent in S1 radiculopathy
(4) latencies are length-dependent and
should be adjusted for patient’s height

320. (E) The H reflex is examined utilizing a modified
motor nerve conduction study technique.
The H reflex is generally present in the soleus
muscle and at time forearm flexor muscles. It
may be more widespread in hyperreflexic conditions
(eg, myelopathy) and pediatrics.
Delayed or absence of the tibial H wave may
reflect S1 radiculopathy or other neuropathic


321. A previously healthy 83-year-old male presents
to your office complaining of acute
abdominal pain but without obvious etiology.
Medical conditions which should be investigated
(1) pneumonia
(2) inflammatory bowel disease
(3) pyelonephritis
(4) inferior wall myocardial infarction

321. (E) The elderly may seek medical attention for
multiple problems with initial complaints of
abdominal pain including: dissecting abdominal
aortic aneurysm in diabetic ketoacidosis,
pneumonia, pyelonephritis, inflammatory
bowel disease, mesenteric ischemia, constipation,
bowel obstruction, peritonitis, and druginduced
GI mucosal irritation.


322. Patients diagnosed with cubital tunnel syndrome
may have
(1) pain and numbness in the ulnar border
of the forearm and hand
(2) clawing of the small finge
(3) Wartenberg sign
(4) a deep aching sensation in the mid

322. (A) The ulnar nerve may be compressed in the
cubital tunnel (cubital tunnel syndrome) which
may lead to atrophy of the first dorsal
interosseous muscle, clawing of the small
finger, weakness of small finger adduction
(Wartenberg sign) and eventually in chronic
ulnar nerve compromise—with weakness of
grip and pinch.


323. A 53-year-old male comes to your office complaining
of foot pain (predominantly in the
heel—but also with diffuse plantar symptoms)
which also occurs at night and can be exacerbated
by prolonged standing or walking. It is
associated with weakness of the phalanges
(impairing the pushing off phase of walking) as
well as sensory loss and paresthesia. After a
complete history and physical examination are
completed, the differential diagnosis may
(1) plantar fasciitis
(2) peripheral neuropathies
(3) posterior tibial nerve entrapment
(4) tarsal tunnel syndrome

323. (E) Tarsal tunnel syndrome is not a common
source of foot discomfort and needs to be distinguished from multiple other causes of pain
in the foot including: painful peripheral neuropathies,
medial plantar nerve entrapment (which
may occur in joggers), posterior tibial nerve entrapment
symptoms tend to be located in medial plantar
heel area, abductor digiti quinti nerve
entrapment (usually with burning pain in heel pad
area), and plantar fasciitis. Plantar fasciitis pain
may be diffuse or migrate but with time is usually
noted at the inferior aspect of the heel (around the
medial calcaneal tuberosity) mainly, although typically
severe with the first few steps in the morning,
tends to diminish through the course of the day
(unless intense or prolonged weight-bearing activity
is under taken).


324. The diagnostic criteria for CRPS I—as accepted
in 1994 by the International Association for the
Study of Pain (IASP)—includes which of the
(1) The presence of an initiating noxious
event, or a cause of immobilization
(2) Continuing pain, allodynia, or hyperalgesia
with which the pain is disproportionate
to any inciting event
(3) Evidence at some time of edema,
changes in skin blood flow, or abnormal
sudomotor activity in the region of pain
(4) This diagnosis is excluded by the existence
of conditions that would otherwise
account for the degree of pain and

324. (E) Although, somewhat controversial and different
from various proposed research criteria,
the diagnosis of CRPS I, includes:
1. The presence of an initiating noxious event
or a cause of immobilization.
2. Continuing pain, allodynia, or hyperalgesia
with which the pain is disproportionate
to any inciting event.
3. Evidence at some time of edema, changes
in skin blood flow, or abnormal sudomotor
activity in the region of the pain.
4. This diagnosis is excluded by the existence
of condition that otherwise would account
for the degree of pain and dysfunction.


325. The paroxysmal hemicranias are rare benign
headache disorders that may typically be associated
(1) conjunctival injection
(2) rhinorrhea
(3) ptosis
(4) eyelid edema

325. (E) Paroxysmal hemicranias may be chronic
(CPH) (eg, daily) or episodic (EPH) (eg, discrete
headache period or separated by periods
of remission) characterized by severe, excruciating,
throbbing, boring, or pulsatile pain
affecting the orbital, supraorbital, and temporal
The pain tends to be associated with at
least one of the following signs or symptoms
ipsilateral to the painful side:
1. Conjunctival injection
2. Nasal congestion
3. Lacrimation
4. Ptosis
5. Rhinorrhea
6. Eyelid edema
Attacks may occur at any time—occasionally
waking patients from sound sleep and
tend to last for 2 to 25 minutes (although may
linger a couple of hours). The patient generally
has 1 to 40 attacks per day.


326. Which of the following statement(s) is (are)
(1) The most common cause of thoracic
radiculopathy is diabetes mellitus
(2) The most common levels affected by
herniated disc at cervical level are C4-5,
C5-6, and C6-7
(3) L4-5 disc is more commonly herniates
than L5-S1
(4) The nerve roots involved most commonly
in thoracic outlet syndromes are
C8 and T1

326. (E)
1. Although thoracic radiculopathy has been
described to result from multiple etiologies
including tumor, scoliosis, infection, spondylosis,
and herniated disc, diabetes mellitus is
described as the most common cause.
2. The lower cervical discs are most commonly
affected by herniation.
3. The frequency of L4-5 herniation is 45%
compared to 42% at the level of L5-S1. With
L4-5 herniation, L5 nerve root is most commonly
4. Lower cervical nerve roots of brachial
plexus, that is, C8 and T1 nerve roots are
most commonly affected in thoracic outlet


327. The characteristics of conus medullaris syndrome
(1) asymmetric paraplegia
(2) symmetric paraplegia
(3) bladder function preservation
(4) upper motor neuron lesion signs

327. (C) Epidural spinal cord compression is compression
of spinal cord or cauda equina nerve
roots from a lesion outside the dura mater.
Epidural spinal cord or cauda equina compression
is the second most common neurologic complication
of cancer, occurring in up to 10% of
patients. The most common tumors causing
metastatic epidural compression are breast, lung,
prostate, lymphoma, sarcoma, and kidney. Conus
medullaris lesions typically cause a rapidly progressive
symmetric perineal pain followed by
early autonomic dysfunction, saddle sensory loss,
and motor weakness. Limited straight leg raise
test usually points to an epidural or intradural
extramedullary lesion causing root compression,
whereas segmental pain and sacral sparing suggest
intramedullary disease.


328. Which of the following statement(s) is (are)
true for central pain of spinal cord origin?
(1) Most common etiology is of traumatic
(2) Most common type of pain in these
patients is spontaneous steady, burning,
or dysesthetic pain affecting approximately
96% of patients
(3) Bowel and bladder dysfunction can be
seen in these patients
(4) Most patients will develop cord central
pain within 1 to 6 months of causative
lesion although some may present more
than 5 years out

328. (E)
1. The incidence of spinal cord pain has been
estimated to be in the range of 6.4% to 94% of
patients who experience spinal cord injury.
2. Patients may describe a variety of pain types;
however, the three most common types are
spontaneous steady, spontaneous neuralgic, and evoked pain including allodynia and
hyperpathia. According to a study of 127
patients with spinal cord pain by Boureau
and colleagues, 75% of patients reported
burning pain.
3. Bowel and bladder dysfunction may be
associated with spinal cord injury depending
on the level and extent of injury.
4. Onset is typically within 1 to 6 months of
the injury. When the onset was delayed
beyond 1 year, 56% of the patients were
found to suffer from a syrinx.


329. A positive Froment sign indicates which of
the following?
(1) Weakness of first dorsal interosseous
(2) Weakness of flexor pollicis brevis
(3) Weakness of adductor pollicis
(4) Weakness of hypothenar muscles

329. (A) Froment sign is positive when ulnar nerve
dysfunction is present. Froment sign is tested
by placing a piece of paper between patient’s
thumb and index finger and checking the position
of the thumb as the examiner tries to pull
the paper away from the patient. Normally the
distal joint of the thumb remains in extension
but if there is ulnar nerve dysfunction the tip of
the thumb flexes significantly to increased pressure
in attempt to keep the paper from moving.


330. The potential for drug-induced painful neuropathies
exist with which of the following
(1) Amiodarone
(2) Metronidazole
(3) Pyridoxine
(4) Vincristine

330. (E) Drug-induced painful neuropathies may
include toxoids (especially with doses greater
than 200 mg/m2), cisplatinum, vincristine, amiodarone,
metronidazole, and pyridoxine (especially
at doses greater than 200-300 mg/d).


331. Spinal cord stimulation (SCS) has been used
for the treatment of
(1) failed back surgery syndrome
(2) CRPS
(3) angina
(4) peripheral vascular disease

331. (E) SCS has been utilized by clinicians for a variety
of chronic pain issues. Although a large body
of work has been published, precise mechanisms
of action of SCS remain elusive. Animal
studies suggest that SCS triggers release of serotonin,
substance P, and γ-aminobutyric acid
(GABA) within the spinal cord dorsal horn.