Types of Pain

A 45-year-old patient with metastatic breast carcinoma is prescribed 30 mg of sustained-release morphine (MS Contin) twice a day and one 15-mg tablet of immediate-release morphine (MSIR) every 6 hours as needed for breakthrough pain. On her routine follow-up visit she reports that she routinely uses MSIR four times a day with satisfactory pain control on most days and no major side effects. What would be your best course of action in this situation?

Prescriptions should be left unchanged

MS Contin should be changed to 40 mg of OxyContin twice a day and 5 mg of oxycodone every 6 hours as needed for breakthrough pain

Fentanyl patch of 25 µg/h should replace MS Contin with 15 mg of MSIR every 6 hours as needed for breakthrough pain

MS Contin should be increased to 60 mg twice a day with MSIR 15 mg every 6‐hours as needed for breakthrough pain

MS Contin should be increased to 60 mg twice a day, and MSIR should be discontinued

If a patient routinely uses breakthrough medications, the daily total amount should be converted to a sustained-release dose and added to the current maintenance dose.

Approximately in what percentage of patients with malignancies does pain unrelated to cancer occur?

Less than 2%

3%

7.5%

11%

25%

Approximately 3% of pain syndromes in cancer patients are unrelated to the underlying malignancy or cancer treatment. Most commonly, pain is caused by degenerative disc disease, arthritis, fibromyalgia, or migraine and has often predated the diagnosis of cancer.

There is a significant incidence of neuropathic pain in a cancer patient with brachial plexopathy. The etiology of the brachial plexopathy in such a patient may be caused by direct tumor infiltration or radiation fibrosis. Electrophysiologic evaluation with nerve conduction velocity (NCV) study and electromyography (EMG) helps to distinguish between the two etiologies. Which of the following findings of NCV/EMG is‐the most helpful to differentiate between the‐direct tumor infiltration and the radiation fibrosis etiologies of brachial plexopathy?

Segmental nerve conduction slowing

Myokymia

Fibrillation potentials

Positive sharp waves

Decreased amplitude of the compound muscle action potential (CMAP)

Segmental nerve conduction slowing, fibrillation potentials, positive sharp waves, and decreased amplitude CMAPs are all helpful in determining the presence of brachial plexopathy in general. Myokymia is present in 63% of patients with radiation fibrosis induced brachial plexopathy. Brachial plexopathy caused by direct tumor infiltration has a low incidence of myokymia. Myokymia is a continuous but brief involuntary muscle twitching that gives the appearance of wormlike rippling of the muscle. It can be determined very distinctly by EMG.

If bony metastases are present, which primary cancer location has the best 5-year survival prognosis?

Myeloma

Breast

Prostate

Thyroid

Kidney

A 5-year survival for a cancer patient with documented skeletal metastases varies widely depending on location of the primary tumor: myeloma—10%; breast—20%; prostate—25%; lung—less than 5%; kidney—10%; thyroid—40%; melanoma—less than 5%.

The most frequent spinal cord symptom or sign in patients with carcinomatous meningitis is

nuchal rigidity

back pain

reflex asymmetry

positive straight leg raise test

weakness

Reflex asymmetry occurs in 67% of patients with carcinomatous meningitis and is the most frequent spinal cord–related sign. The frequency of nuchal rigidity, back pain, positive straight leg raise test, and weakness is 11%, 25%, 13%, and 33%, respectively.

Which of the following would most likely be responsible for the central pain syndrome?

Epidural spinal cord compression

Metastatic bony destruction of the vertebrae with a nerve root compression

Metastatic involvement of the cranial nerves

Carcinomatous meningitis

Radiation myelopathy

Central pain syndromes are relatively rare in cancer patients. Although epidural spinal cord compression is almost always painful, central pain is not the predominant symptom. Nociceptive input from progressive bony destruction by metastases is the usual cause of pain, with or without concurrent radicular pain from nerve root compression. Radiation myelopathy is the central pain syndrome.

All of the following are true about the World Health Organization (WHO) analgesic ladder, EXCEPT

it is a method for relief of cancer pain based on a small number of relatively inexpensive drugs

it has three steps

step one involves the use of opioids

it suggests to use only one drug from each group at a time

it is a simple and effective method for controlling cancer pain

The WHO analgesic ladder is based on the premise that most patients throughout the world gain adequate pain relief if health care professionals learn how to use a few effective and relatively inexpensive drugs well. Step 1 of the ladder involves the use of nonopioids. If this step is ineffective, go to step 2 and add an opioid for mild to moderate pain. Step 3 substitutes an opioid for moderate to severe pain in step 2. Only one drug from each group should be used at a time. Adjuvant drugs can be used in all steps.

The following are all true about methadone, EXCEPT

it has a highly variable oral bioavailability

it is a low cost medication

it has no known active metabolites

it has N-methyl-d-aspartate (NMDA) receptor agonist properties

it has high lipid solubility

Methadone has a variable oral bioavailability between 41% and 99% and, therefore, should be started with extra caution (low initial dose and slow subsequent increases). Methadone differs from all other opioids by its noncompetitive antagonist activity at the NMDA receptors. Activation of NMDA receptors has been shown to play a role in development of tolerance to analgesic effects of opioids, as well as in the pathologic sensory states, such as neuropathic pain, inflammatory pain, ischemic pain, allodynia, and spinal states of hypersensitivity.

58-years-old patient with metastatic prostate cancer is taking sustained-release morphine (MS Contin) every 8 hours with a total daily dose of 225 mg with optimal pain control. Because of some circumstances, he has to be converted to transdermal therapeutic system fentanyl (TTS-fentanyl). What is the correct dose of fentanyl patch equivalent to the current dose of MS Contin for this patient?

25 µg/h every 72 hours

50 µg/h every 48 hours

75 µg/h every 72 hours

100 µg/h every 48 hours

125 µg/h every 72 hours

As a rough guide for conversion, the 8-hourly dose of MS Contin (225/3 = 75 mg in this case) can be considered equal to the micrograms per hour dose of TTS-fentanyl. In one study, most people had satisfactory pain profiles with frequency of administration of every 3 days. Only in 24% of subjects in the study required different frequency of administration varying from 48 to 60 hours.

Which of the following is true with respect to central pain syndromes?

The most common cause of central pain state are lesions located in the brainstem

The Wallenberg syndrome (lateral medullar syndrome) is characterized by contralateral facial sensory loss and Horner syndrome

The most common lesions that produce thalamic pain syndrome are infarctions

Spinal cord lesions rarely cause sensory deficits

Central pain syndromes of spinal origin usually respond to epidural steroids

• A. The most common cause of central pain states are spinal cord lesions.
• B. The Wallenberg syndrome is usually vascular in origin, and characterized by crossed sensory findings that include ipsilateral facial sensory loss, Horner syndrome, and contralateral body impairment of pain and temperature loss.
• C. The most common lesions that produce thalamic pain syndrome are infarctions, followed by arteriovenous malformations (AVMs), neoplasms, abscesses, plaque of multiple sclerosis, traumatic injury, and others.
• D. Spinal cord lesions are the most common cause of central pain syndromes and present with areas of sensory loss resulting from disruption of the spinothalamic tract.
• E. The treatment of central pain of spinal origin is complex with poor response to most forms of therapy.

Peripheral neuropathy is a common pain syndrome characterized by which of the following?

Asymmetric paresthesias and proximal motor impairment

Proximal more than distal sensory impairment

Most peripheral neuropathies may be classified as demyelinating, axonal, or mixed

Peripheral mononeuropathy is the most common peripheral nerve disease in patients with long-standing diabetes mellitus

Nerve conduction studies only measure conduction through small unmyelinated fibers, so impairment of the fast conducting fibers may go undetected

Sensory symmetric impairment is commonly seen distally with progression to more proximal areas of the limbs as the disease progresses. Peripheral polyneopathy is the most common initial manifestation of diabetes mellitus. The nerve conduction studies measure only the fastest conducting fibers, leaving injury of small-diameter fibers, which transmit pain sensations, undiagnosed.

Events seen in the development of neuropathic pain are

following nerve injury, there is a decreased activity of the sodium channels which allows for abnormal conduction through pain facilitating fibers

wide dynamic range neurons in the dorsal horn respond with increased frequency as the intensity of the repeated afferent stimulus increases

an increase in potassium channels would facilitate an amplified afferent activity

C-polymodal nociceptors are activated by low-threshold mechanical, thermal, and chemical stimuli

γ-aminobutyric acid (GABA) and glycine are released in the dorsal horn and augment the response of second order neurons

Following nerve injury there is an increase in the expression of sodium channels in the neuroma and in the DRG. Consistent with the role of sodium channels in the development of neuropathic pain is blockage of their activity by low plasma concentrations of lidocaine. A reduction in potassium channel activity leads to increased afferent activity. The largest population of afferent axons is C-polymodal nociceptors that are activated by high-threshold mechanical, thermal, and chemical stimuli.

Examples of neuropathic pain conditions include all, EXCEPT

complex regional pain syndrome (CRPS)

diabetic peripheral neuropathy

postherpetic neuralgia (PHN)

Raynaud phenomenon

phantom limb pain

Raynaud phenomenon is not a neuropathic pain condition, but rather a vascular condition (although, potentially sympathetically mediated and/or sustained).

Which of the following conditions is more likely to be associated with neuropathic pain?

Traumatic nerve injury

Stroke

Syringomyelia

Multiple sclerosis

Large myelinated fiber neuropathy

Although not completely known some conditions predispose to the development of neuropathic pain. The relative frequency is 5% for patients with traumatic nerve injury, 8% for patients after stroke, 28% for patients with multiple sclerosis, and 75% for patients with syringomyelia. Neuropathies with predominant involvement of large myelinated fibers are usually not painful.

A patient with CRPS responds well to sympathetic ganglion block. The results of this block can lead you to say which of the following about this particular pain condition?

It is vascularly mediated

It is sympathetically mediated

It is sympathetically maintained

It is less severe than previously thought

It will not respond well to spinal cord stimulation

We do not know if it is sympathetically mediated (B) from the block since this does not provide evidence of etiology. We do not know the involvement of vascularity since the block is affecting sympathetic outflow and precludes vascular evidence (which could be mediated by a host of other physiologic events). There is no clinical evidence to support a less severe case (D) and, the evidence suggests that it will respond to spinal cord stimulation (E).

When the stimulus of light touch exerts pain which of the following is exhibited?

Hyperalgesia

Allodynia

Hypereflexemia

Paresthesia

Hypertouchemia

Following tissue damage, there is a decrease of the threshold for noxious stimuli (hyperalgesia), which may be associated to perception of pain to normally innocuous stimuli. This phenomenon is termed allodynia. Allodynia is most likely caused by plastic changes at the level of the primary sensory fibers and spinal cord neurons.

A 74-year-old male has a left lower extremity amputation after a long bout with uncontrolled diabetes mellitus (DM). What are the chances that this patient will develop phantom pain?

33%

49%

55%

90%

75%

While ranges between 2% and 88% are quoted in the literature, most current studies state that between 60% and 80% of patients will develop phantom pain after amputation.

The patient mentioned in the previous question develops early and severe phantom pain:

The patient is more likely to suffer from long-standing pain

The patient is less likely to suffer from long-standing pain

The patient is more likely to suffer incapacitating pain for 1 year that will subside rather abruptly

It is likely that the patient will develop neuropathic pain in the extremity contralateral to the amputation

The pain will likely be refractory to treatment with anticonvulsants

Patients who develop early and severe phantom pain are more likely to suffer from chronic pain, whereas individuals who are pain-free at the beginning are less likely to develop significant pain. However, prospective studies with a maximum follow-up period of 2 years suggest that phantom pain may diminish with time.

The number of amputees who have severe phantom limb pain is

20% to 30%

60% to 80%

5% to 10%

1% to 2%

45% to 55%

While phantom limb pain is seen in 60% to 80% of amputees, only 5% to 10% have severe pain.

Preamputation pain

is more likely to lead to phantom pain if the amputation is traumatic

may sensitize the nervous system, explaining why some individuals may be more susceptible to development of chronic phantom pain

is more likely to lead to phantom pain if the amputation is secondary

is similar in character and localization to the subsequent phantom pain in 80% of patients

is less likely to lead to phantom pain if the amputation is in the upper extremities

Some retrospective studies, but not all have pointed to preamputation pain as a risk factor for phantom pain. It has been hypothesized that preoperative pain may sensitize the nervous system, explaining why some individuals may be more susceptible to development of chronic pain.

• A. It has been noted that patients with traumatic amputations, who had no pain prior to the amputation, develop pain to the same extent as patients with preoperative pain who endure amputations after significant medical pathology.
• C. There is no correlation between the development of phantom pain and whether the amputation was primary or secondary. Primary amputation is when the limb is lost at the time of the injury. Secondary amputation is when the limb is surgically removed in a hospital.
• D. Phantom pain may mimic preamputation pain in both character and localization. Preamputation pain may persist in some patients, but it is not the case in the majority of patients.
• E. Site of amputation has not been found to have a role in determining whether preamputation pain leads to phantom pain.

Of the following, which does not play a role in the mechanism for generating phantom pain?

Peripheral sensitization

Central sensitization

Cortical reorganization

Increased thalamus response to stimulation

Sympathetic inhibition

• E. The sympathetic nervous system may play a role in generating and, in particular, in maintaining, phantom pain.

After limb amputation and deafferentation in adult monkeys, there is reorganization of the primary somatosensory cortex, and while these changes may be unique to the cortex, they may also be, at least in part, the result of changes at the level of the thalamus and perhaps even brain stem or spinal cord. After dorsal rhizotomy, the threshold to evoke activity in the thalamus and cortex decreased, and the mouth and chin invade cortices corresponding to the representation of arm and fingers that have lost their normal afferent input. In humans similar reorganization has been observed. In the thalamus, neurons that normally do not respond to stimulation in amputees begin to respond and show enlarged somatotropic maps. A cascade of events seems to be involved in generating phantom pain and it starts in the periphery, spinal cord, brain stem, thalamus, and finally ends in the cerebral cortex.

All of the following are true about primary dysmenorrhea, EXCEPT

pain is transmitted via the thoracolumbar spinal segments and pelvic afferents

the etiology of pain includes myometrial contractions leading to intense intrauterine pressure and uterine hypoxia

prostaglandins and leukotriene production that sensitizes afferent pelvic nerves is part of its pathogenesis

endometriosis and adenomyosis are its most common causes

altered central receptivity of the afferent input from the pelvis is thought to be relevant in its development

Primary dysmenorrhea is defined as menstrual pain without pelvic pathology. Endometriosis and adenomyosis are the most common causes of secondary dysmenorrhea.

All of the following are true about chronic endometriosis, EXCEPT

ovaries, cul-de-sac, uterine tubes, surface of the bowel are among the most common sites of pathologic implantation of the functioning endometrial tissue

retrograde menstruation, lymphatic spread, and hematogenous spread of the endometrial tissue are all thought to play a role in endometriosis etiology

pain occurs only with menses

definitive diagnosis can be made by visualization of the characteristic lesions without a mandatory histologic confirmation

leuprolide acetate (Lupron) may be an effective treatment of the symptoms of chronic endometriosis

The pain of endometriosis can occur with menses or sexual intercourse or can always be present. It can also mimic any known pelvic pathology. Answers A, B, D, and E are all correct.

All of the following are correct, EXCEPT

pudendal nerve takes origin from S2, S3, and S4 roots bilaterally

bilateral denervation of the inferior hypogastric nerves is as effective as a lumbar epidural block with respect to sensory input from the uterus and cervix

many patients with hymenal neuropathy are so emotional and complain so violently that the pelvic examination is not possible

patients with sympathetic pelvis syndrome have a deep pain in the pelvis not associated with physically detectable abdominal wall or muscle tenderness

ilioinguinal and iliohypogastric neuropathy is rarely associated with the surgeries in the lower abdominal wall area

All of the common reasons for the inadequate management of acute pain in a hospital setting are true, EXCEPT

the common idea that pain is merely a symptom and not harmful in itself

the fact that opioids have no potential for addiction when administered strictly for acute pain

lack of understanding of the pharmacokinetics of various agents

lack of appreciation of variability in analgesic response to opioids

prescription of inappropriately low doses of opioids and thinking that opioids must not be given more often than every 4 hours

Opioids have the potential for addiction even when administered for acute pain. However, it is the exaggerated common fear of the potential for addiction to opioids that often interferes with adequate pain management. The rest of the answers are correct.

The following are true about pathologic (nonphysiological) pain, EXCEPT

it occurs in the context of central sensitization

it occurs in the context of peripheral sensitization

it outlasts the stimulus

it spreads to nondamaged areas

it is elicited by A-δ and C fibers, but not A-β fibers, which transmit touch sensation

It is recognized that long-term changes occur within the peripheral and central nervous system following noxious input. This neuroplasticity alters the body’s response to usual peripheral sensory input. In pathologic pain conditions, stimulation of A-β fibers, normally eliciting response to touch, may elicit pain.

Perioperative administration of NSAIDs

does not reduce the demand for opioids during and after the surgery

is contraindicated because of increased possibility of bleeding

has synergistic effect with opioids

has its analgesic effect only through peripheral mechanisms

is not associated with the concerns for postoperative bleeding

Even though there have been some concerns regarding the risks of perioperative NSAIDs, including intra- and postoperative bleeding, they continue to have a useful role. Combination of NSAIDs and opioids has a synergistic analgesic effect, as they act at the different sites of pain pathways. More new evidence is emerging that NSAIDs exert their analgesic effects also through the central mechanisms.

All of the following are true about the NMDA receptors, EXCEPT

they are involved in development of “windup” facilitation

NMDA agonists reduce development of tolerance to opioids

NMDA receptors are involved in development of central sensitization

NMDA receptors are involved in changes of peripheral receptive fields

NMDA receptors are involved in induction of oncogenes and long-term potentiation

It has been demonstrated that the administration of an NMDA antagonist reduces the development of tolerance to morphine. The rest of the answers are correct.

As compared with somatic pain, all of the following are true about visceral pain, EXCEPT

it may follow the distribution of a somatic nerve

it is dull and vague

it is often periodic and builds to peaks

it is often associated with nausea and vomiting

it is poorly localized

The following are the usual features of the somatic pain: well localized, sharp and definite, often constant (sometimes periodic); it is rarely associated with nausea usually when it is deep somatic pain with bone involvement; it may be following the distribution of a somatic nerve. In contrast, the visceral pain: is poorly localized, diffuse, dull, and vague; it is often periodic and builds to peaks (sometimes constant); it is often associated with nausea and vomiting.

The following statements are true regarding preemptive analgesia, EXCEPT

preemptive analgesia is helpful in reducing postoperative pain in part by reducing the phenomenon of central sensitization

early postoperative pain is not a significant predictor of long-term pain

local anesthetics, opioids, and NSAIDs can be used for preemptive analgesia

preemptive analgesia may have the potential to prevent the development of chronic pain states

preemptive analgesia is thought to reduce neuroplastic changes in the spinal cord

It has been demonstrated that early postoperative pain is a significant predictor of long-term pain. The rest of the answers are correct.

The following statements are true regarding multimodal analgesia, EXCEPT

it may include NSAIDs, acetaminophen, local anesthetics, and opioids in the same patient

it is beneficial because of the synergistic action of the individual medications with different sites of action along the pain pathways

it is not very valuable owing to an increase in the incidence of side effects

it facilitates early mobilization of the postsurgical patient

it expedites return to normal parenteral nutrition

Multimodal analgesia makes it possible to significantly reduce the total consumption of opioids intra- and postoperatively. Therefore, opioid side-effects are minimized, including inevitable opioid-induced GI stasis that delays the resumption of normal enteral nutrition after surgery.

All of the following statements about PHN are correct, EXCEPT

midthoracic dermatomes is one of the most common sites for PHN

men are affected more often than women in a ratio of 3:2

ophthalmic division of the trigeminal nerve is one of the most common sites for PHN

PHN may occur in any dermatome

PHN has an incidence of 9% to 14.3%

PHN affects women more often than men, in a ratio of approximately 3:2. The rest of the answers are correct.

PHN is defined as

any pain associated with the herpes zoster

pain caused by herpes zoster for more than 1 month

persistent pain with a significant neuropathic component in a dermatomal distribution

pain caused by herpes zoster for more than 3 months

neuropathic pain in midthoracic dermatomes caused by herpes simplex virus

PHN is defined as pain caused by herpes zoster for more than 1 month.

Which of the following is true about the management of PHN?

Approximately 40% of patients with PHN have either incomplete or no relief from treatment

Prevention of herpes zoster is not nearly as important as a multimodal treatment of PHN

Current multimodal treatment of PHN is nearly 100% effective, independent of the duration of the symptoms

Current multimodal treatment of PHN is nearly 100% effective as long as it is started within the first month of the symptoms of PHN

Current multimodal treatment of PHN is nearly 100% effective as long as it is started immediately after the first symptoms of herpes zoster

As many as 40% of patients with PHN have either incomplete or no relief from treatment. Because of this, the future may lie with prevention through vaccination and early aggressive treatment of herpes zoster with antivirals and analgesics to reduce the extent of the nerve damage and sensitization that may correlate with PHN.

The following are true about the use of antidepressants in treatment of PHN, EXCEPT

amitriptyline has been shown to be effective in treatment of PHN, but has significant limitations in the long term because of its side effects

selective serotonin reuptake inhibitors (SSRIs) have been found to be equally or more effective in treatment of PHN than the older generation of tricyclic antidepressants (TCAs) or selective norepinephrine reuptake inhibitors (SNRIs)

SNRIs have been shown to be more effective than placebo in treatment of PHN

antidepressant therapy in PHN is built on sound, scientific basis

one of the significant side effects of TCAs is their anticholinergic properties

Experience with serotonergic antidepressants, such as clomipramine, trazodone, nefazodone, fluoxetine, and zimelidine, in PHN has been disappointing. The evidence supporting the use of noradrenergic agents is more compelling. The rest of the answers are correct.

Which of the following is true about use of opioids in the treatment of PHN?

The use of opioids is not justified for nonmalignant pain

Opioids tend to be less effective for the treatment of neuropathic pain than nonneuropathic pain

Opioids were not found to be useful in the treatment of PHN

The use of opioids should be avoided in combination with antidepressants because of the risk of excessive central nervous system (CNS) suppression

The use of opioids in PHN should be avoided owing to the increased potential of addiction

There has been evidence that opioids do not relieve neuropathic pain as well as nonneuropathic pain. However, there is also evidence that opioids have been successfully used for the treatment of PHN.

Which of the following is the most common cause of autonomic neuropathy in the developed world?

Leprosy

Diabetes mellitus (DM)

Human immunodeficiency virus (HIV) infection

Heavy metal poisoning

Idiopathic etiology

DM is the most common cause of autonomic neuropathy, and peripheral neuropathy in general, in the United States, as well as in the rest of the developed world. Leprosy is the most common cause of peripheral neuropathy in the world.

Diabetic amyotrophy

has a poor prognosis

has better prognosis when it involves upper extremities

usually resolves within 1 to 2 years spontaneously

has better prognosis when the symptoms do not involve pain

it is directly related to hyperglycemia

Diabetic amyotrophy starts with pain and involves the lower extremities. It has a good prognosis and usually resolves spontaneously in 12 to 24 months. It is not directly related to hyperglycemia.

The following are true about the distal sensorimotor polyneuropathy, EXCEPT

it is the most common neuropathic manifestation of both type 1 and type 2 diabetes

it starts distally and spreads proximally

initial symptoms may involve numbness and tingling in the toes or feet

it is a length-dependent neuropathy

it is usually asymmetrical

Distal sensorimotor polyneuropathy is a symmetrical length-dependent process with dying-back or dropout of the longest nerve fibers—myelinated and unmyelinated. All other answers are correct.

The prevalence of diabetic neuropathy in DM patients is

less than 1% at diagnosis of DM, rising to 10% in patients diagnosed for longer than 5 years

about 10% at diagnosis of DM, rising to more than 50% in patients diagnosed for longer than 5 years

about 50% at diagnosis of DM, rising to almost 100% in patients diagnosed for longer than 5 years

about 50% at diagnosis of DM, and does not change significantly with time

no such studies have been done so far

It is generally agreed that the prevalence of neuropathy is about 10% at diagnosis of DM, rising to 50% or more in patients diagnosed for longer than 5 years.

Patients with diabetic distal sensorimotor polyneuropathy initially may complain of numbness and tingling in the toes or feet, which then slowly spreads proximally over months to years. Eventually, numbness and tingling appear in the fingertips, as the symptoms of diabetic polyneuropathy progress to

ankle

knee

mid-thigh

buttock and groin

abdomen

Which of the following is the most widely accepted cause of trigeminal neuralgia?

Demyelinating conditions, as trigeminal neuralgia is most common in patients with multiple sclerosis

Direct trauma of the trigeminal ganglion at the level of the foramen ovale, before branching into its three branches

Arterial cross-compression of the trigeminal nerve in the posterior fossa

Tumors of the posterior fossae

Poor vascular supply to the affected trigeminal branch

It is accepted that the most common cause of trigeminal neuralgia is arterial cross- compression of the trigeminal nerve in the posterior fossa, as suggested by Jannetta in 1982. Electron microscopy of trigeminal nerve biopsies taken from patients with trigeminal neuralgia has shown areas of axonal swelling and demyelination adjacent to the area of arterial compression. Although trigeminal neuralgia is more common in patients with multiple sclerosis, only a small portion of patients with trigeminal neuralgia suffer from multiple sclerosis and does not explain the majority of the cases.

Which of the following is true regarding medical management for the treatment of trigeminal neuralgia?

Anticonvulsant medications are usually considered as the second line of treatment

Beneficial effects of carbamazepine are better in elderly patients

Risk of side effects of carbamazepine increase with age

Carbamazepine has proven to be the most effective treatment for trigeminal neuralgia, independently of the side-effect profile

Because of the unlikelihood of serious side effects with surgery, all patients should consider this option first

Carbamazepine is likely to be beneficial in up to 70% of the patients. Incidence of side effects is often higher in elderly patients especially if the drug escalation is too fast. Allergic rash is seen in up to 10% of the patients and high concentration of the drug may be associated with fluid retention promoting cardiac problems. Carbamazepine is a potent hepatic enzyme inducer which can potentially lead to undesirable drug-to-drug interactions. Although microsurgical exploration of the posterior fossa is the highly successful, it is a major surgery with 0.5% risk of mortality and major morbidity. The effectiveness of pimozide for trigeminal neuralgia is better than carbamazepine, but the high frequency of side effects limits its clinical use.

The gasserian ganglion

receives exclusively proprioceptive information from the muscles of mastication

the mandibular branch is located medial to the ophthalmic branch

the two medial branches are sensory while the lateral branch is partially motor

the ganglion lies out of the cranium, in the Meckel cave

the foramen rotundum is used as landmark for the blockage of the trigeminal ganglion

The trigeminal ganglion receives sensation from the oral mucosa, scalp, nasal areas, face, and teeth. Proprioceptive information is transmitted into the ganglion from the mastication and extraocular muscles. The peripheral branches of the ganglion are the ophthalmic, the maxillary, and the mandibular, which are organized somatotropically, with the ophthalmic branch located dorsally, the maxillary branch is intermediate, and the mandibular nerve is located ventrally. The gasserian ganglion lies within the cranium, in the middle cranial fossa. The posterior border of the ganglion includes the dura of the Meckel cave. The landmark to perform the trigeminal ganglion block is the foramen ovale and not the foramen rotundum.

Giant cell arteritis is characterized by which of the following?

Affects almost exclusively Asian population

As other forms of vasculitis, giant cell arteritis commonly involves skin, kidneys, and lungs

Males are more commonly affected

It is more common in older patients, with a peak incidence between 60 to 75 years of age

Visual loss is the presenting symptom in over 50% of the patients

The giant cell arteritis affects almost exclusively the white population although it can occur in worldwide. Unlike other forms of vasculitis it rarely affects skin, kidneys, or lungs. Females are affected 3 times more often than males. Visual loss is now considered to affect between 6% to 10% of patients in most series.

According to the International Headache Society Diagnostic Criteria, analgesic rebound headache is

headache that resolves or reverts within 2 weeks after discontinuation of the suspected medication

headache that worsens after intake of analgesics and reduces in intensity and frequency with reduction in the analgesic dose

the intensity of the headache decreases in intensity proportionally to the decrease in the dose of analgesic

headache greater than 15 days per month that has developed or markedly worsened during medication overuse

headache that increases in intensity with the use of morphine, most likely because of the cerebral vasodilation mediated by histamine release

Analgesic rebound headache resolves or reverts to its previous pattern within 2 months of discontinuing of the overused medication.

Cluster headaches are characterized by

lancinating unilateral headache that is commonly triggered by stress factors

the pain is strictly unilateral and autonomic symptoms occur ipsilateral to the pain

the onset is slow with progressive worsening of the pain over several hours with an attack usually lasting 3 to 4 days

melatonin is commonly indicated as therapy for the acute attack

cluster headaches are more common in elderly patients

The first statement better describes trigeminal neuralgia. Cluster headache affects more males than females with a 5:1 ratio and can begin at any age. Attacks are severe, stabbing, screwing, unilateral pain, occasionally preceded by premonitory symptoms, with sudden onset, and rapid crescendo. Therapeutic interventions for the acute attack include oxygen, triptans, dihydroergotamine, ketorolac, chlorpromazine, or intranasal lidocaine, cocaine, or capsaicin. Melatonin has been found to be moderately effective as a preventive treatment in episodic and chronic cluster headache.

Which of the following describes the pathophysiologic changes seen in migraine?

Inflammation of hypothalamic structures leads to low threshold stimulation of vascular and meningeal tissues

Central sensitization mediated by attribution to activation of β-fibers in the trigeminal system, mediates extracranial hypersensitivity

Large cerebral vessels, pial vessels, large sinuses, and the dura, are innervated by fibers originating from the sphenopalatine ganglion

Activation and threshold reduction of the trigeminocervical complex by its most caudal cells

In acute attacks, a marked reduction in vasoactive substances, including substance P, calcitonin gene related peptide (CGRP), and nitric oxide is commonly seen

Sterile neurogenic inflammation is often seen after stimulation of the trigeminal ganglion, which innervates large cerebral vessels, pial vessels, large sinuses, and the dura via unmyelinated C fibers. In acute attacks of migraine, substance P, CGRP, and nitric oxide mediate the neurogenic inflammation.

Which of the following is correct regarding headache?

Migraine is the most common form of headache

Tension-type headache (TTH) is commonly aggravated by physical exercise

The presence of nausea, vomiting, photophobia, or phonophobia excludes the diagnosis of TTH

The most common form of migraine is associated with aura

Comorbid conditions associated with chronic migraine include depression, anxiety, and panic disorders

TTH is the most common type of headache. Aura is present in only 20% of patients suffering from migraine. Although chronic daily headache diagnostic criteria for probable TTH requires no nausea or vomiting as one of the criteria or absence of photophobia, or phonophobia, nausea may be seen in 4.2% of patients with TTH, while phonophobia is reported in 10.6% of them.

Hundred precent oxygen inhalation is a safe and effective method for acute treatment of

chronic daily headache

TTH

migraine with aura

cluster headache

glossopharyngeal neuralgia

Inhalation of 100% oxygen at 7 to 12 L/min is effective in treating the majority of cluster headache sufferers when used continuously for 15 to 20 minutes. Generally oxygen inhalation is not considered to be effective in any other form of primary neurovascular headache.

The Ramsay Hunt syndrome is caused by the infection of the varicella-zoster virus of the

sphenopalatine ganglion

gasserian ganglion

geniculate ganglion

glossopharyngeal ganglion

stellate ganglion

Which of the following characterizes the spontaneous intracranial hypotension (SIH)?

Is the same entity as post–dural puncture headache (PDPH)

Headache is consistently unilateral

Orthostatic headache is pathognomonic

Patients complain of bitemporal headache

To confirm the diagnosis, it is required that cerebrospinal fluid (CSF) opening pressures be below 60 mm H2O

PDPH and SIH are two distinct clinical entities with similar presentation. The headache is always bilateral, located in the occipital and/or frontal area. Although low CSF pressure is often noted, it is not necessary to confirm the diagnosis.

A 20-year-old male presents to the clinic with complaints of moderate headaches located bilateral in the forehead, parietal, and occipital areas. The pain is dull and continuous and not associated with nausea, vomiting, photophobia, and phonophobia. The patient recalls that the symptoms started 1 year ago and have been constant since they started. No abnormalities where observed on physical examination, sinus computed tomography (CT), or brain MRI. The patient has occasionally tried over-the-counter analgesics with no relief. Which of the following is the most likely diagnosis?

Status migrainosus

Rebound headache

New daily persistent headache

Cluster headache

Classical migraine

New daily persistent headache is a chronic, unremitting headache of sudden onset, daily pattern. The duration of the headache should be at least 3 months. Some important features include its moderate severity, bilateral location, and lack of nausea, vomiting (N/V), photophobia, and phonophobia (P/P). On the other hand, status migrainosus is a severe debilitating migraine, associated with N/V, P/P, and with duration longer than 72 hours but that typically do not exceed 2 weeks. The other diagnoses are not consistent with the symptoms.

Which of the following is a theory that may explain the presence of aura?

Cortical spreading depression

The vascular theory

Hormonal fluctuation

Estrogen withdrawal

Cerebral idiopathic hypertension

The previously known classic migraine (migraine with aura) is preceded by visual aura that starts 20 to 40 minutes before the migraine and is characterized by spreading scintillations reflecting a slow propagation of neuronal and glial excitation emanating from one occipital lobe. Cortical spreading depression (CSD) presents with dramatic shifts in cortical steady potential (DC), temporary increases in extracellular ions and excitatory neurotransmitters (glutamate), and transient raise, followed by sustained decrease in cortical blood flow. The vascular theory proposed that migraine with aura is caused by intracranial cerebral vasoconstriction and the headache by reactive vasodilation. Despite that, the theory can not explain the prodromal symptoms or why some antimigraine medications are not effective. Hormonal fluctuations and estrogen withdrawal may explain the higher incidence of migraine in female patients during their reproductive years, but are not related to the presence of aura. Cerebral idiopathic hypertension is a form of headache of unknown etiology.

Chronic low back pain and neck pain persists 1 year or longer in what percentage of patients?

5% to 10%

15% to 20%

20% to 25%

25% to 60%

60% to 75%

The published literature commonly states that 80% to 90% of low back pain resolves in about 6 weeks, irrespective of the administration or type of treatment, with only 5% to 10% of patients developing persistent back pain. Contrary to this assumption, actual analysis of research evidence shows that chronic low back and neck pain persist 1 year or longer in 25% to 60% of adult and/or elderly patients.

The prevalence of zygapophysial (facet) joint involvement in low back pain is

5% to 10%

10% to 15%

15% to 45%

50% to 60%

65% to 70%

Based on evaluations utilizing controlled diagnostic blocks, the prevalence of zygapophysial or facet joint involvement has been estimated to be between 15% and 45% in heterogeneous groups of patients with chronic low back pain.

A 58-year-old with metastatic lung cancer suddenly complains of severe back pain. Symptoms of early spinal cord compression include all of the following, EXCEPT

rapid onset

symmetric and profound weakness

spasticity

increased deep tendon reflexes

urinary retention and constipation

The clinical picture of metastatic epidural spinal cord compression is uniformly reported as pain, weakness, sensory loss, and autonomic dysfunction. Metastatic epidural spinal cord compression initially presents with severe back pain in 95% of cases. After weeks of progressive pain, the patient may develop weakness, sensory loss, autonomic dysfunction, and reflex abnormalities. Bladder and bowel dysfunction are rarely presenting symptoms, but may appear after sensory symptoms have occurred. The exception to this generalization develops with compression of the conus medullaris, which presents as acute urinary retention and constipation without preceding motor or sensory symptoms.

Specific indications for discography include all of the following, EXCEPT

further evaluation of abnormal discs to assess the extent of abnormality

patients with persistent, severe symptoms in whom other diagnostic tests have revealed clear confirmation of a suspected disc as the source of pain

assessment of patients who have failed to respond to surgical procedures to determine if there is possible recurrent disc herniation

assessment of discs before fusion to determine if the discs within the proposed fusion segment are symptomatic

assessment of minimally invasive surgical candidates to confirm a contained disc herniation or to investigate contrast distribution pattern before intradiscal procedures

Patients with severe, persistent symptoms (discogenic in origin) that have been confirmed by other diagnostic evaluations do not need to undergo further evaluation by discography. Specific uses for discography include, but are not limited to: further evaluation of demonstrably abnormal discs to help assess the extent of abnormality or correlation of the abnormality with clinical symptoms (in case of recurrent pain from a previously operated disc and a lateral disc herniation); patients with persistent, severe symptoms in whom other diagnostic tests have failed to reveal clear confirmation of a suspected disc as the source of pain; assessment of patients who have failed to respond to surgical procedures to determine if there is painful pseudoarthrosis or a symptomatic disc in a posteriorly fused segment, or to evaluate possible recurrent disc herniation; assessment of discs before fusion to determine if the discs within the proposed fusion segment are symptomatic and to determine if discs adjacent to this segment are normal; and assessment of minimally invasive surgical candidates to confirm a contained disc herniation or to investigate contrast distribution pattern before intradiscal procedures.

The following signs and symptoms are consistently found with cervical radiculopathy, EXCEPT

gait disturbances

normal muscle tone

negative Babinski test

weak tendon reflexes

positive axial compression test (Spurling maneuver)

Gait disturbances are a feature of cervical myelopathy, not radiculopathy. Other signs and symptoms of cervical radiculopathy include upper extremity sensory disturbances and muscle weakness.

All of the following are reasons associated with smoking as a risk factor for low back pain, EXCEPT

mineral content of the lumbar vertebrae is decreased

fibrinolytic disc activity is altered

blood flow and nutrition to the disc are diminished

disc pH is higher

increased degenerative changes of the lumbar spine

Experimental studies have given support to the hypothesis that blood flow and nutrition to the disc are diminished in smokers, the pH of the disc is lowered, disc mineral content is lower, fibrinolytic activity is changed, and there are increased degenerative changes seen in the lumbar spine.

All of the following treatments have strong evidence to back their use when treating acute low back pain, EXCEPT

muscle relaxants effectively reduce low back pain

bed rest is effective for treating low back pain

continuing normal activity gives equivalent or faster recovery from acute low back pain

NSAIDs prescribed at regular intervals are an effective treatment for acute low back pain

different types of NSAIDs are equally effective at treating low back pain

There is strong evidence from randomized controlled trials that bed rest is not effective for treating acute low back pain.

Age-related changes in the intervertebral discs include all of the following, EXCEPT

the dimensions of the lumbar intervertebral discs decrease with age

collagen lamellae of the annulus fibrosis increases in thickness

distinction between the nucleus pulposus and annulus fibrosis becomes less apparent

the nucleus pulposus is less able to transmit weight directly

80% of nucleus pulposus cells in the elderly exhibit necrosis

Narrowing of the intervertebral discs has long been considered one of the signs of pathologic aging of the lumbar spine, but recent data has shown that notion to be untrue. Large-scale postmortem analysis have shown lumbar disc height and diameter to actually increase with age. The anterior-posterior diameter increases by about 10% in females and 2% in males. Disc height has been shown to increase by about 10% in most lumbar discs.

Radiculopathy is a neurologic condition associated with all of the following characteristics, EXCEPT

numbness

weakness

pain

compression of axons

ischemia of axons

Radiculopathy is a condition in which conduction within the axons of a spinal nerve or its roots are blocked. It can result in numbness and weakness secondary to conduction block in sensory and motor neurons respectively. Conduction blockade can be caused by compression or ischemia. It is important to make the distinction that radiculopathy does not cause pain. It may, however, be associated with pain.

Adverse effects of epidurally administered steroids include all of the following, EXCEPT

Cushing syndrome

osteoporosis

avascular bone necrosis

hypoglycemia

suppression of the hypothalamus-pituitary axis

The major theoretical complications of corticosteroid administration include suppression of pituitary-adrenal axis, hypercorticism, Cushing syndrome, osteoporosis, avascular necrosis of bone, steroid myopathy, epidural lipomatosis, weight gain, fluid retention, and hyperglycemia.

Relative contraindications to epidural steroid injections include

preexisting neurologic disorder (ie, multiple sclerosis)

sepsis

therapeutic anticoagulation

localized infection at injection site

patient refusal

Absolute contraindications to epidural steroid injections include sepsis, infection at injection site, therapeutic anticoagulation, and patient refusal. Relative contraindications include preexisting neurologic conditions, prophylactic low-dose heparin, thrombocytopenia, and uncooperative patients.

L4-L5 disk herniation with L5 nerve root involvement includes

numbness over the medial thigh and knee

weakness with dorsiflexion of great toe and foot

difficulty walking on toes

pain in lateral heel

quadriceps weakness

L4-L5 disc herniation with L5 nerve root involvement involves: pain over the sacroiliac joint, hip, lateral thigh, and leg; numbness over the lateral leg and first three toes; weakness with dorsiflexion of great toe and foot; difficulty walking on heels; possible foot drop; and internal hamstring reflex diminished or absent. Numbness over the medial thigh and knee, and quadriceps weakness are indicative of L3-L4 disc herniation with L4 nerve root involvement. Difficulty walking on toes and lateral heel pain are common with L5-S1 disk herniation involving the S1 nerve root.

In patients with chronic low back pain, the prevalence of sacroiliac joint pain is

10%

15%

20%

25%

30%

Fifteen percent of patients with chronic low back pain have sacroiliac joint pain.

Match spondylolysis with the correct definition.

Neurologic condition in which conduction is blocked to the axons of a spinal nerve or its roots. It results in numbness and weakness

An acquired defect caused by fatigue fracture of the pars interarticularis

Pain that arises as a result of irritation of a spinal nerve or its roots

Displacement of a vertebrae or the vertebral column in relationship to the vertebrae below it

Periostitis of spinous processes or inflammation of the affected ligament

Spondylolysis is an acquired defect that results from a fatigue fracture of the pars interarticularis (the part of the lamina that intervenes between the superior and inferior articular processes on each side). Spondylolisthesis is the displacement of a vertebrae or the vertebral column in relationship to the vertebrae below. Kissing spines (also known as Baastrup disease) affects the lumbar spinous processes. Excessive lumbar lordosis or extension injuries to the lumbar spine cause adjacent spinous processes to clash and compress the intervening interspinous ligament. This results in a periostitis of the spinous process or inflammation of the affected ligament. Radiculopathy is a neurologic condition in which conduction blocks the axons of a spinal nerve or its roots that results in numbness and weakness. Radicular pain is pain that arises as a result of irritation of a spinal nerve or its roots.

Match spondylolisthesis with the correct definition.

Neurologic condition in which conduction is blocked to the axons of a spinal nerve or its roots. It results in numbness and weakness

An acquired defect caused by fatigue fracture of the pars interarticularis

Pain that arises as a result of irritation of a spinal nerve or its roots

Displacement of a vertebrae or the vertebral column in relationship to the vertebrae below it

Periostitis of spinous processes or inflammation of the affected ligament

Spondylolysis is an acquired defect that results from a fatigue fracture of the pars interarticularis (the part of the lamina that intervenes between the superior and inferior articular processes on each side). Spondylolisthesis is the displacement of a vertebrae or the vertebral column in relationship to the vertebrae below. Kissing spines (also known as Baastrup disease) affects the lumbar spinous processes. Excessive lumbar lordosis or extension injuries to the lumbar spine cause adjacent spinous processes to clash and compress the intervening interspinous ligament. This results in a periostitis of the spinous process or inflammation of the affected ligament. Radiculopathy is a neurologic condition in which conduction blocks the axons of a spinal nerve or its roots that results in numbness and weakness. Radicular pain is pain that arises as a result of irritation of a spinal nerve or its roots.

Match kissing spines with the correct definition.

Neurologic condition in which conduction is blocked to the axons of a spinal nerve or its roots. It results in numbness and weakness

An acquired defect caused by fatigue fracture of the pars interarticularis

Pain that arises as a result of irritation of a spinal nerve or its roots

Displacement of a vertebrae or the vertebral column in relationship to the vertebrae below it

Periostitis of spinous processes or inflammation of the affected ligament

Spondylolysis is an acquired defect that results from a fatigue fracture of the pars interarticularis (the part of the lamina that intervenes between the superior and inferior articular processes on each side). Spondylolisthesis is the displacement of a vertebrae or the vertebral column in relationship to the vertebrae below. Kissing spines (also known as Baastrup disease) affects the lumbar spinous processes. Excessive lumbar lordosis or extension injuries to the lumbar spine cause adjacent spinous processes to clash and compress the intervening interspinous ligament. This results in a periostitis of the spinous process or inflammation of the affected ligament. Radiculopathy is a neurologic condition in which conduction blocks the axons of a spinal nerve or its roots that results in numbness and weakness. Radicular pain is pain that arises as a result of irritation of a spinal nerve or its roots.

Match radiculopathy with the correct definition.

Neurologic condition in which conduction is blocked to the axons of a spinal nerve or its roots. It results in numbness and weakness

An acquired defect caused by fatigue fracture of the pars interarticularis

Pain that arises as a result of irritation of a spinal nerve or its roots

Displacement of a vertebrae or the vertebral column in relationship to the vertebrae below it

Periostitis of spinous processes or inflammation of the affected ligament

Spondylolysis is an acquired defect that results from a fatigue fracture of the pars interarticularis (the part of the lamina that intervenes between the superior and inferior articular processes on each side). Spondylolisthesis is the displacement of a vertebrae or the vertebral column in relationship to the vertebrae below. Kissing spines (also known as Baastrup disease) affects the lumbar spinous processes. Excessive lumbar lordosis or extension injuries to the lumbar spine cause adjacent spinous processes to clash and compress the intervening interspinous ligament. This results in a periostitis of the spinous process or inflammation of the affected ligament. Radiculopathy is a neurologic condition in which conduction blocks the axons of a spinal nerve or its roots that results in numbness and weakness. Radicular pain is pain that arises as a result of irritation of a spinal nerve or its roots.

Match radicular pain with the correct definition.

Neurologic condition in which conduction is blocked to the axons of a spinal nerve or its roots. It results in numbness and weakness

An acquired defect caused by fatigue fracture of the pars interarticularis

Pain that arises as a result of irritation of a spinal nerve or its roots

Displacement of a vertebrae or the vertebral column in relationship to the vertebrae below it

Periostitis of spinous processes or inflammation of the affected ligament

Spondylolysis is an acquired defect that results from a fatigue fracture of the pars interarticularis (the part of the lamina that intervenes between the superior and inferior articular processes on each side). Spondylolisthesis is the displacement of a vertebrae or the vertebral column in relationship to the vertebrae below. Kissing spines (also known as Baastrup disease) affects the lumbar spinous processes. Excessive lumbar lordosis or extension injuries to the lumbar spine cause adjacent spinous processes to clash and compress the intervening interspinous ligament. This results in a periostitis of the spinous process or inflammation of the affected ligament. Radiculopathy is a neurologic condition in which conduction blocks the axons of a spinal nerve or its roots that results in numbness and weakness. Radicular pain is pain that arises as a result of irritation of a spinal nerve or its roots.

Evidence regarding the value of epidural injections for the management of chronic spinal pain demonstrates the following:

Limited with interlaminar lumbar epidural steroid injections for short-term relief of lumbar radicular pain

Strong with interlaminar lumbar epidural steroid injections for long-term relief of lumbar radicular pain

Moderate for lumbar transforaminal epidural steroid injections for short-term relief of lumbar radicular pain

Strong for lumbar transforaminal epidural steroid injections for long-term relief of lumbar radicular pain

Strong for caudal epidural steroid injections for short-term relief of lumbar radiculopathy and post–lumbar laminectomy syndrome

In managing lumbar radicular pain with interlaminar lumbar epidural steroid injections, the evidence is strong for short-term relief and limited for long-term relief. In managing cervical radiculopathy with cervical interlaminar epidural steroid injections, the evidence is moderate. The evidence for lumbar transforaminal epidural steroid injections in managing lumbar radicular pain is strong for short-term and moderate for long-term relief. The evidence for cervical transforaminal epidural steroid injections in managing cervical nerve root pain is moderate. The evidence is moderate in managing lumbar radicular pain in post–lumbar laminectomy syndrome. The evidence for caudal epidural steroid injections is strong for short-term relief and moderate for long-term relief, in managing chronic pain of lumbar radiculopathy and post–lumbar laminectomy syndrome.

All of the following statements regarding intervertebral disc innervation are true, EXCEPT

nerve plexuses that innervate the intervertebral discs are derived from dorsal rami

in normal lumbar intervertebral discs, nerve fibers are only found in the outer third of the annulus fibrosis

discs painful on discography and removed with operation have nerve growth deep into the annulus and into the nucleus pulposus

disc fissuring is a trigger for neo-innervation of a disc

the anterior and posterior nerve plexuses accompany the anterior and posterior longitudinal ligaments

The sources of the nerve endings in the lumbar discs are two extensive microscopic plexuses of nerves that accompany the anterior and posterior longitudinal ligaments. The nerve plexuses that innervate intervertebral discs are derived from the lumbar sympathetic trunks. The dorsal rami supply innervation to the muscles of the back and zygapophysial joints. In normal lumbar intervertebral discs, nerve fibers are only found in the outer third of the annulus fibrosis. Discs painful on discography and removed with operation have nerve growth deep into the annulus and into the nucleus pulposus. Disc fissuring is a trigger for neoinnervation and neovascularization of a disc.

Three days after a lumbar epidural steroid injection was given, a 57-year-old male complains of fever and severe back pain over the site where the injection was given. Two days later, the back pain has progressively worsened, and a severe radiating pain goes down the right leg and knee. Which of the following is the most likely complication of the epidural steroid injection?

Epidural abscess

Epidural hematoma

Arachnoiditis

Anterior spinal artery syndrome

Cauda equina syndrome

Development of an epidural abscess is a very rare complication of epidural steroid injections. It needs to be recognized and treated quickly to avoid irreversible injury. Symptoms of an epidural abscess include severe back pain that is followed by radicular pain 3 days later. The initial back pain may not become evident for several days after the injection.

X-ray imaging is recommended for which of the following cause of low back pain?

Disc bulging

Cauda equina syndrome

Spondylolisthesis

Lateral disc herniation

Spinal cord tumors

Plain x-rays are recommended for possible fractures, arthropathy, spondylolisthesis, tumors, infections, stenosis, and congential deformities. CT images are recommended for bone/joint pathologies, lateral disc herniations, stenosis (ie, spinal canal, neuroforaminal, lateral recess), and for those in which an MRI is contraindicated. MRI is recommended for disc herniations, spinal stenosis, osteomyelitis, tumors (ie, spinal cord, nerve roots, nerve sheath, paraspinal soft tissue), and cauda equine syndrome.

Which of the following nerve root and muscle motion combinations is correct?

L2—leg extension

L3—heel walking

L4—toe walking

L5—first toe dorsiflexion

S1—hip flexion

The L2 nerve root is involved with hip flexion, L3 with leg extension, L4 with heel walking, L5 with first toe dorsiflexion (and heel walking), and S1 with toe walking.

Which of the following is the most frequent complication of a laminotomy with discectomy?

Recurrent disc herniation

Infection

Dural tear

Neural injury

Failed back surgery syndrome (FBSS)

Laminotomy with discectomy has a low infection rate, statistically. The most frequent complication is a dural tear. Neural injury may occur as a result of a dural tear and may cause long-term pain and neurologic deficit. Recurrence of the herniation occurs in approximately 5% of cases. Infection and neural injury occurs in less than 0.5% of cases.

Which of the following includes conservative treatment for FBSS?

Discectomy

Chemonucleolysis

Rehabilitation

Laminectomy

Fusion

Conservative treatment is usually the first treatment of choice for patients presenting with FBSS. It consists of medical management of contributing factors (ie, depression, obesity, smoking), rehabilitation, and behavior modification (ie, alcohol or drug dependency).

Favorable prognostic indicators for patients undergoing repeated lumbosacral surgery include all of the following, EXCEPT

female sex

satisfactory outcome from prior surgeries

operative findings of disk herniation

epidural scarring requiring lysis of adhesions

radicular pain

Many prognostic indicators have been implicated in patients undergoing repeat lumbosacral spine surgery. They may or may not be significant for each patient and should be taken into context for the particular patient. Women have been found to have better outcomes than men. Patients with a history of favorable outcomes from prior surgeries tend to have better outcomes as well. A history of few previous surgeries, operative/myelographic findings of disc herniation, and a history of working immediately prior to surgery are all favorable prognostic indicators. Less favorable prognostic indicators include epidural scarring that requires lysis of adhesions and pseudoarthrosis of a prior fusion.

Waddell signs were developed to help identify nonorganic causes of low back pain. They include all of the following, EXCEPT

tenderness

stimulation

distraction testing

regional disturbance

underreaction

Waddell signs are used to help diagnose nonorganic low back pain complaints. Each of the five findings is considered positive if present. Three positive findings are considered highly suggestive of a nonorganic source of pain:

• 1. Tenderness: does not follow dermatomal or referral patterns and is hard to localize.
• 2. Stimulation testing: stimulating distant sites should not cause discomfort.
• 3. Distraction testing: findings when testing the same site are inconsistent when the patient’s attention is distracted.
• 4. Regional disturbance: motor and sensory testing yield nonanatomic findings.
• 5. Overreaction: inappropriate verbal remarks or facial expressions, withdrawal from touch, or posturing inconsistent with touch.

A 25-year-old male presents with progressively worsening neck and back pain and stiffness over 4 months that improves with light exercise and warm showers. Which of the following is the most likely diagnosis?

Rheumatoid arthritis

Ankylosing spondylitis

Psoriatic arthritis

Klippel-Feil syndrome

Reiter syndrome

Ankylosing spondylitis is characterized by pain and stiffness in young males (typically ages 17-35 years) more often than females. It is worse in the morning and improves with mild exercise. The pain will typically last for at least 3 months and be diffuse in nature affecting the low back and spine. Rheumatoid arthritis is an inflammatory polyarthritis that affects middle-aged women more often than men. It typically presents with morning stiffness that improves as the day progresses, and the spine is not affected until late in the disease. Psoriatic arthritis is characterized by inflammation of the skin and joints that typically presents in the fourth and fifth decades of life. Klippel-Feil syndrome is a congenital disorder that is characterized by abnormal fusion of two or more bones in the cervical spine. Reiter syndrome is a reactive arthritis that is characterized by a triad of symptoms: nongonococcal urethritis, conjunctivitis, and arthritis.

Which of the following is a major criteria for cervicogenic headache?

Bilateral head or face pain without sideshift

Pain is superficial and throbbing

Restricted neck range of motion

Pain relief with digital pressure to cervical vertebrae

Lack of relief from anesthetic blockade

The three major criteria for cervicogenic headache include (1) signs and symptoms of neck involvement (precipitation of head pain by: neck movement and/or sustained awkward head positioning, by external pressure over the upper cervical or occipital region on the symptomatic side; restriction of the range of motion in the neck; ipsilateral neck, shoulder, or arm pain of a rather vague nonradicular nature or, occasionally, arm pain of a radicular nature); (2) confirmatory evidence by diagnostic anesthetic blockades; and (3) unilaterality of the head pain without sideshift. Head pain characteristics include moderate-severe, nonthrobbing, and nonlancinating pain, usually starting in the neck, episodes of varying duration, or fluctuating, continuous pain. Other characteristics of some importance: only marginal effect or lack of effect of indomethacin, only marginal effect or lack of effect of ergotamine and sumatriptan, female sex, not infrequent occurrence of head, or indirect neck trauma by history, usually of more than only medium severity.

Neurogenic claudication can be distinguished from vascular claudication by which of the following?

Leg tightness

Pain alleviated with standing

Pain exacerbated with lumbar flexion

No change in pain with exercise

Pain exacerbated with lying supine

Neurogenic claudication pain is secondary to nerve root compression rather than lack of blood supply that is seen with vascular claudication. The pain is exacerbated by standing erect and downhill walking. Improvement comes with lying supine more than lying in the prone position, sitting, squatting, and lumbar flexion. Neurogenic claudication is not made worse with biking, uphill walking, and lumbar flexion, unlike vascular claudication. It is not alleviated with standing.

Neck pain has been suggested to have a multifactorial origin. Which of the following statements regarding neck pain is true?

Workplace interventions are not effective at reducing neck pain

Normal degenerative changes in the cervical spine are a risk factor for pain

Physical activity does not protect against neck pain

Precision work does not increase the risk of neck pain

Social support in the workplace does not affect neck pain

Neck pain has been suggested to have multifactorial etiologies. Risk factors for neck pain that cannot be modified include age, sex, and genetics. There is no evidence that normal cervical spine degenerative changes are a risk factor for neck pain. Modifiable risk factors for neck pain include smoking and exposure to environmental tobacco. Participation in physical activity seems to offer a protective effect. High quantitative job demands, low social support at the workplace, inactive work position, repetitive work, and meticulous work increases the risk of neck pain. There is a lack of evidence that workplace interventions are successful in decreasing neck pain in employees.

In patients with neck pain, what is more predictive at excluding a structural lesion or neurologic compression than at diagnosing any specific etiologic condition?

MRI

Discography

Blood tests

Physical examination

Electrophysiology

In patients with neck pain, the physical examination is more predictive at excluding a structural lesion or neurologic compression than at diagnosing any specific etiologic condition in patients with neck pain. Other assessment tools (ie, electrophysiology, imaging, injections, discography, functional tests, and blood tests) lack validity and utility.

All of the following characteristics are associated with a poor prognosis for neck pain, EXCEPT

prior neck pain

pain resulting from an accident

passive coping techniques

middle age

compensation

Most people with neck pain do not experience a complete resolution of symptoms. Between 50% and 85% of those who experience neck pain at some initial point will report neck pain again 1 to 5 years later. These numbers appear to be similar in the general population, in workers, and after motor vehicle crashes. The prognosis for neck pain also appears to be multifactorial. Younger age was associated with a better prognosis, whereas poor health and prior neck pain episodes were associated with a poorer prognosis. Poorer prognosis was also associated with poor psychologic health, worrying, and becoming angry or frustrated in response to neck pain. Greater optimism, a coping style that involved self-assurance, and having less need to socialize, were all associated with better prognosis. Specific workplace or physical job demands were not linked with recovery from neck pain. Workers who engaged in general exercise and sporting activities were more likely to experience improvement in neck pain. Postinjury psychologic distress and passive types of coping were prognostic of poorer recovery in WAD. There is evidence that compensation and legal factors are also prognostic for poorer recovery from WAD.

Which of the following is the most common complication of fluoroscopically guided interlaminar cervical epidural injections?

Nonpositional headache

Vasovagal reactions

Increased neck pain

Fever

Dural puncture

The reported complications of fluoroscopically guided interlaminar cervical epidural injections are increased neck pain (6.7%), nonpositional headaches (4.6%), insomnia the night of the injection (1.7%), vasovagal reaction reactions (1.7%), facial flushing (1.5%), fever on the night of the procedure (0.3%), and dural puncture (0.3%). The incidence of all complications per injection is 16.8%.

A 54-year-old female complains suddenly of inability to move her legs after a transforaminal epidural steroid injection. On further examination, she is found to have intact light touch sensation, sphincter disturbance, and loss of pain and temperature sensation. What is the most likely diagnosis?

Cauda equina syndrome

Epidural hematoma

Epidural abscess

Transient paraplegia

Anterior spinal artery syndrome

Anterior spinal artery syndrome classically presents in older patients with abrupt motor loss, sphincter disturbance, and nonconcordant sensory examination with preservation of sensation to light touch but loss of pain and temperature. It may also occur during aortic procedures. When anterior spinal artery syndromes occur during or after transforaminal epidural steroid injection, the patient may have abrupt back or abdominal pain after injection. An MRI will demonstrate a T2 signal change consistent with cord ischemia/infarct. Anterior spinal artery ischemia may be caused by arteriosclerosis, tumors, thrombosis, hypotension, air or fat embolism, toxins, or other causes. Particulate (steroid) substances, arterial injury, or vascular spasm are other potential causes and have been implicated as significant possibilities for the occurrence of ischemic events after transforaminal epidural steroid injections.

A 57-year-old diabetic male presents with a new onset of neck pain over the past several hours; the pain is beginning to move down each arm equally. Two days ago he had a cervical epidural injection which he receives periodically for a herniated disc. On physical examination, his temperature is 102.4°F, his cervical spine is exquisitely tender to palpation and he complains of radicular pain down both arms. The most likely organism causing this presentation is

Pseudomonas

Escherichia coli

Streptococcus pneumoniae

Hemophilus influenza

Staphylococcus aureus

A spinal epidural abscess must be recognized promptly and treated quickly, otherwise extreme morbidity can result. It may be separate or associated with vertebral osteomyelitis. Diabetic, alcoholic, IV drug using patients, and immunocompromised patients are all at increased risk. Staphylococcus aureus is the most common organism involved. An affected patient usually presents with neck pain that rapidly progresses to radicular symptoms. Quadriplegia can result if left untreated. Treatment involves surgical removal and antibiotic management.

The following statements are true regarding the pathologic mechanism in HIV-related neuropathy, EXCEPT

HIV is found within endoneurial macrophages

HIV is found within Schwann cells

antisulfatide antibodies are one of the humoral factors responsible for demyelinating diseases in AIDS patients

secretion of cytokines by the HIV-infected glial cells may generate tissue-specific autoimmune attack

the pathologic mechanisms in HIV-related neuropathies are not well understood

The pathophysiology of HIV-related neuropathies is still not well understood. The current understanding is that it is not related to the direct effect of the virus itself. HIV is not found within ganglionic neurons of Schwann cells, but only in endoneurial macrophages, which may generate a tissue-specific autoimmune response by secretion of cytokines, which, in turn, promotes trafficking of activated T cells and macrophages within the endoneurial parenchyma.

Pain syndromes of neuropathic nature occur in approximately 40% of AIDS patients with pain. Several types of peripheral neuropathies have been described in patients with HIV and AIDS. The most common painful neuropathy encountered in patients with HIV and AIDS is

mononeuritis multiplex

polyradiculopathy

cauda equina syndrome

painful toxic neuropathy

predominantly sensory neuropathy of AIDS

The predominantly sensory neuropathy of AIDS affects up to 30% of people with HIV infection and AIDS and is the most commonly encountered.

The most important pathophysiologic event in‐sickle cell anemia, which explains most of its‐clinical manifestations, is vascular occlusion. The following are the pathophysiologic processes that lead to vascular occlusion in patients with sickle cell disease (SCD), EXCEPT

erythrocyte dehydration

distortion of the shape of erythrocytes

polymerization of the sickle cell hemoglobin on deoxygenation

decreased deformability of erythrocytes

decreased stickiness of erythrocytes

The primary process that leads to vascular occlusion is the polymerization of sickle cell hemoglobin on deoxygenation, which in turn results in distortion of the shape of red blood cells (RBCs), cellular dehydration, decreased deformability, and increased stickiness of RBCs, which promotes their adhesion to and activation of the vascular endothelium.

A physician has to exercise extra caution when attributing SCD patient’s complaints of pain to behavioral deviations, such as drug-seeking behavior, because

patients in real pain, such as sickle cell pain, do not develop addiction to opioids

most patients with SCD have substance abuse and addiction, as they are exposed to opioids early in life

there is a higher incidence of controlled-substance diversion in SCD patients

sickle cell pain could be the prodrome of a serious and potentially fatal complication of SCD

severe pain, such as sickle cell pain, should only be managed by an experienced physician subspecializing in pain management

SCD is unlike other pain syndromes where the provider can make decisions on treatment based solely on the pain and its associated behavior. A primary care physician, for example, taking care of a middle-aged patient with job-related low back pain may decide to expel the patient from his or her care if the patient in question demonstrates suspicious drug-seeking behavior. Doing the same with patients who have SCD could be counterproductive. There are anecdotes of patients with SCD who were dismissed from certain programs only to be found dead at home within 24 hours after dismissal or to be admitted to other hospitals with serious complications. Sickle cell pain could be the prodrome of a serious and potentially fatal complication of SCD in some patients.

What makes the pain of SCD unique in its acuteness and severity?

SCD patients tend to have a decreased threshold to pain because of prolonged and early exposure to severe pain in life

SCD patients have increased tolerance to opioids and opioid-related hyperalgesia

SCD pain pathophysiology involves a combination of ischemic tissue damage and secondary inflammatory response

Repetitive SCD crises lead to ischemic damage of the CNS and subsequent central sensitization to pain

SCD patients tend to anticipate and respond with a spectacular behavioral manifestation to pain, because of its cyclic feature

Tissue ischemia caused by vascular occlusion resulting from in situ sickling causes infarctive tissue damage, which in turn initiates a secondary inflammatory response. The secondary response may enhance sympathetic activity by means of interactions with neuroendocrine pathways and trigger release of norepinephrine. In the setting of tissue injury, this release causes more tissue ischemia, creating a vicious cycle. It is the combination of ischemic tissue damage and secondary inflammatory response that makes the pain of SCD unique in its acuteness and severity.

At initial presentation, objective signs of a painful SCD crisis, such as fever, leukocytosis, joint effusions, and tenderness, occur in

less than 10% of patients

about 25% of patients

about 50% of patients

about 75% of patients

more than 90% of patients