Pain Boards Flashcards

1
Q

Describe the difference between migraines, cluster headaches, tension-type headaches, and chronic paroxysmal hemicrania.

A

Migraines
- Usually associated with nausea, vomiting, and sensitivity to light/sound/smells.
- An aura (visual/sensory/motor symptoms) may
precede the attack although migraine without aura is more common
- Pain is usually unilateral and throbbing
- Episodes can last hours to days
- Believed to involve cortical spreading depression, activation of the trigeminovascular system, and CNS modulation of the pain-producing structures of the cranium
- Can be triggered by abrupt decreases in levels of estrogen

Cluster headaches

  • Associated with ipsilateral lacrimation, eye redness, eyelid edema, stuffy nose, rhinorrhea, and sweating
  • Repetitive headaches that occur at the same time each day
  • Episodes last minutes to hours.
  • Can occur for a week to several months and are followed by a period of remission
  • Can be treated with 100% oxygen

Tension-type headaches
- Bilateral, pressing/tightening sensation.

Chronic paroxysmal hemicrania is like a cluster headache, but episodes are shorter and more frequent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How should you treat a pt with known contrast allergy, but who requires a procedure with contrast?

A

Pretreatment at 12 and 2 hours pre-procedure with Prednisone, Ranitidine, and Diphenhydramine. Pt should also receive 25 mg IV Diphenhydramine immediately pre-procedure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What factors determine local anesthetic potency, speed of onset, and duration of action?

A

Potency- lipid solubility

Onset - pKa

Duration- protein binding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does Botox work?

A

Botox produces localized flaccid paralysis by blocking the release of acetylcholine at the neuromuscular junction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is Carbamazepine used for? How does it work? What are the common side effects? What type of monitoring is required?

A

Drug of choice for trigeminal neuralgia

Selectively blocks Na channels on active nerve fibers, and has no effect on normally functioning C and A-delta fibers

Main side effects are nausea, vomiting, and sedation

Pts should have blood tests every 2 to 4 months, due to risk of agranulocytosis and aplastic anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is Topiramate used for? How does it work? What are the side effects?

A

Used for neuropathic pain

Affects sodium and calcium channels, enhances the action of inhibitory GABA, and inhibits excitatory glutamate receptors

Side effects include weight loss, sedation, kidney stones, and ocular glaucoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do prostaglandins enhance the transmission of pain?

A

They increase the release of neurotransmitters such as substance P and glutamate from primary neurons, increase the sensitivity of second-order neurons, and inhibit the release of descending inhibitory neurotransmitters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Nabumetone? What are the benefits?

A

Nabumetone is an NSAID prodrug which needs to be converted to its active form

Theoretically has fewer gastric side effects, but this is unproven

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How and where does Baclofen work?

A

Baclofen is a GABA-B receptor agonist that binds to presynaptic receptors in the dorsal horn of the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the mechanism of action of various muscle relaxants (Baclofen, Carisoprodol, Tizanidine, Cyclobenzaprine)?

A

Baclofen - GABA-B agonist

Carisoprodol (SOMA) - inhibits descending reticular activating system

Tizanidine (Zanaflex) - central alpha-2 agonist

Cyclobenzaprine (Flexeril) - effects on brain stem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are some common TNF inhibitors? What are they used for? How do they work?

A

Common inhibitors include Infliximab (Remicade), D2E7 (Humira), and Etanercept (Enbrel)

Used for the treatment of rheumatoid arthritis

Inhibit TNF, reduce markers of inflammation, and slow structural damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the effects that each opioid receptor is responsible for.

A

Mew-1
- supraspinal analgesia

Mew-2

  • spinal analgesia
  • dependence, respiratory depression, miosis, GI effects, pruritis

Delta

  • supraspinal and spinal analgesia
  • euphoria

Kappa

  • spinal analgesia
  • sedation, dysphoria, respiratory depression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the three molecular classes of opioids?

A

1) Pheneathrenes
- morphine, hydromorphone, codeine, oxycodone, oxymorphone, and hydrocodone

2) Phenylpiperidines
- meperidine, fentanyl, sufantanil, alfentanil, and remifentanil

3) Diphenylhepatanes
- methadone and propoxyphene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Aside from pain control, what use does Meperidine have? What are the side effects?

A

May have a beneficial effect in the setting of post-anesthetic shivering

Side effects include cardiac effects (orthostatic hypotension and cardiac depression), anticholinergic effects, neurotoxic effects due to accumulation of metabolite (worse with renal failure), potential for serotonin syndrome (when mixed with MAOIs, SSRIs, Tramadol, or Methadone), and local anesthetic effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

A pt with a clean history and I signs of misuse is requiring almost 5 times the originally prescribed oxycodone dose to control their pain. What is a possible explanation?

A

Pt may have genetically low levels of the cytochrome P450 enzyme required to metabolize oxycodone into oxymorphone
- Occurs in about 10% of pts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What nerve root is tested when checking the following reflexes: biceps, brachioradialis, triceps, patellar, Achilles

A

Biceps - C5

Brachioradialis - C6

Triceps - C7

Patellar - L4

Achilles- S1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What information can an EMG/NCS give you?

A

Site of injury (anterior horn, spinal root, plexus, nerve, NMJ, or muscle)

Type of nerve involved (motor, sensory, or autonomic)

Nature of pathology (demyelination or axonal degeneration)

Time course (acute or chronic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How would you perform a maxillary nerve block?

A
  • mandibular notch is identified
  • 22 gauge needle is advanced perpendicular to the skin at the posterior inferior border of the notch
  • needle is advanced until it hits the lateral ptyergoid plate
  • needle is then withdrawn slightly and redirected anteriorly superiorly
  • needle is advanced toward the pterygopalatine fossa until a parasthesia is obtained
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

When performing a lumbar sympathetic block, there can be inadvertent nerve block. Which nerve is most commonly blocked and how does it manifest?

A

The genitofemoral nerve is very susceptible at the L4-5 level

Manifests as weakness and numbness in the groin, anterior thigh, and quads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is Tramadol’s mechanism of action? What type of patients should it be avoided in?

A

Mechanism includes agonism at the mu receptor and inhibition of norepinephrine and serotonin reuptake

Should be avoided in pts with seizure history (can lower seizure threshold) and in pts taking SSRIs (increases risk of serotonin syndrome)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe primary afferent neurons. What are the different types?

A

Primary afferent neurons have cell bodies in the DRG and axons that reach out to peripheral sites

  • No spontaneous activity
  • Increased activity corresponds with increased stimuli intensity

Three main types:
A-beta (large myelinated) - rapid speed - specialized endings
A-delta (small myelinated) - intermediate speed - low threshold - specialized endings
- responsible for “fast epicritic (1st) pain”
C (small unmyelinated) - slow speed - high threshold - free nerve endings
- responsible for “slow protopathic (2nd) pain”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the significance of the spinal rexed lamina?

A

Spinal rexed lamina are the site of secondary nociceptive neurons

Also the site of opioid receptors

Lamina I - marginal zone = “nociceptive specific”
Lamina II - substantia gelatinosa = highest density of nociceptors
Lamina V - nucleus proprius = “wide dynamic range” neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the ascending pain pathways from the dorsal horn.

A

Spinoreticulothalamic tract = light touch
- ipsilateral, ventrolateral

Spinothalamic tract = pain

  • contralateral, ventrolateral
  • two main routes
    1) lateral thalamus to somatosensory cortex = sensory and discriminative aspects of pain
    2) medial thalamus to cingulate and insula = emotional aspects of pain and autonomic reflex responses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define hyperalgesia, allodynia, paresthesia, dysesthesia, and hyperpathia.

A

Hyperalgesia = exaggerated nociceptive response to a moderately noxious stimuli

Allodynia = nociceptive response generated by a normally innocuous stimulus

Paresthesia = abnormal sensation (not necessarily pain)

Dysesthesia = spontaneous pain

Hyperpathia = a state in which pain is persistent, radiates, and may become amplified

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Describe how tissue injury leads to peripheral and central sensitization. What receptor is involved in central sensitization?

A

Peripheral sensitization is due to:

  • Persistent/increased spontaneous nociceptor discharge
  • Enhanced response to stimuli

Central sensitization (“wind up”) due to:

  • Repetitive C fiber input
  • Increased response to stimuli from increased kinase activity and changes in gene transcription
  • Enhanced receptive field size due to collateral nociceptor innervation

NMDA receptor is thought to be involved in central sensitization

  • NMDA receptors are composed of NR1, NR2 (A, B, C, and D), and NR3 (A and B) subunits
  • The NR2B subunit appears particularly important for nociception
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe the changes/mechanisms that lead to neuropathic pain after nerve injury.

A

Widespread changes include increased activity of sodium channels and decreased activity of potassium channels, leading to increased afferent activity

Peripheral changes

  • Retrograde chromatolysis
  • Wallerian degeneration (starts distally; slow 1 mm/day; faster peripherally compared to centrally; motor faster than sensory)
  • Sprouting and neuroma formation
  • Invasion of inflammatory cells

Central changes

  • Changes in the DRG including alteration of protein, channel, and receptor expression
  • Increased DRG spontaneous activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the mechanism by which opioids produce analgesia

A

Opioid receptors alter the conductance of potassium and calcium ion channels

Inhibit the release of neurotransmitters presynpatically

Inhibit neuronal firing via hyperpolarization postsynaptically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the concerns regarding migraine medications that contain Propoxyphene?

A

Issues with Propoxyphene:

  • Daily use my cause rebound headaches
  • Has been associated with cardiac dysrhythmias
  • Metabolism occurs in the liver to norpropoxyphene which can cause toxic side effects
  • Has not been shown to be any stronger than aspirin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Define physical dependence.

A

Physical dependence - state of adaptation that is manifested by a withdrawal syndrome that can be produced by abrupt cessation, rapid dose reduction, and/or administration of an antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the contraindications for stellate ganglion block?

A

Absolute contraindications

  • Anticoagulation
  • Pneumothorax on the contralateral side (due to high risk of pneumothorax on side of procedure)
  • Recent MI (due to blockade of cardiac accelerator fibers)

Relative contraindications
- Glaucoma and impaired cardiac conduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Placement of a spinal cord electrode at which cervical levels will cover the distribution for: upper neck pain, radial nerve pain, median nerve pain, and ulnar nerve pain?

A

Upper neck pain = C2-3

Radial nerve pain = C4-5

Median nerve pain = C5-6

Ulnar nerve pain = C6-7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

If a stellate ganglion block is performed and shows technical success (ptosis, miosis, nasal congestion, etc.) but does not cause a change in temperature or pain, what is the likely reason?

A

In some cases the upper extremity may be supplied by the T2 and T3 grey rami communicantes (Kuntz fibers)

  • Do not pass through the stellate ganglion
  • Have been implicated in inadequate relief of sympathetically maintained pain despite a good stellate ganglion block.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Describe the metabolism of local anesthetics.

A

Amide local anesthetics are metabolized in the liver

Ester local anesthetics are metabolized in the plasma by plasma pseudocholinesterase
- Metabolism results in the formation of PABA, which is associated with allergic reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

The genitofemoral nerve is made up of which nerve roots?

A

L1 and L2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Describe intervertebral disk anatomy

A

The inner nucleus pulposis is made up of mostly water but also some Type II collagen

The outer annulus fibrosis is mostly Type I collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the Dallas classification of IVD annular tears?

A

Grade 0 = normal disk
Grade 1 = contrast leaks to inner 1/3 of annulus
Grade 2 = contrast leaks to middle 1/3 of annulus
Grade 3 = contrast extends out to outer 1/3 of annulus
Grade 4 = contrast leaks to outer edge of annulus with concentric spread
Grade 5 = complete rupture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What receptors do opioids block in the spinal cord?

A

Mu and Kappa receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the treatment for a brachial plexus avulsion injury? What are the side effects?

A

Treatment is radiofrequency DREZ lesioning

Side effects include motor weakness, sensory deficits, and ataxia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

How does nerve compression lead to neuropathic pain?

A

Nerve compression leads to hypoxia/damage to large myelinated nerve fibers

This loss of segmental inhibition leads to unopposed C fiber stimulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Describe post-herpetic neuralgia

A

Caused by Herpes Zoster (Shingles)
- Virus stays dormant in DRG

Most commonly affects thoracic dermatomes
- Can also affect the opthalmic division of the trigeminal nerve (V1)

Characterized by pain that persists 30 days or more after rash onset
- Due to ischemic loss of myelinated fibers

Affects women more than men

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What are the causes of central pain? What is the theorized mechanism? Are there any treatment options?

A

Causes:

  1. Stroke
    - Almost 90% of all central pain is caused by CVAs, but less than 10% report pain within the first year
  2. Spinal cord injury
  3. Multiple sclerosis

Mechanism is thought to involve disruption or injury of the spinothalamocortical tract

Motor cortex stimulation may be a possible treatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What signs/symptoms are seen if local anesthetic is accidentally injected around the brain stem?

A

Bilateral headaches

4th or 6th nerve palsies

Pupillary changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

When performing a glossopharyngeal nerve block, which nerves are also commonly blocked??

A

Spinal accessory nerve
- Weakness of the SCM and trapezius

Vagus nerve
- Reflex tachycardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

The trigeminal ganglion lies in what structure?

A

Within Meckel’s cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Describe the “drug schedule”

A

The drug schedule ranks drugs based on abuse potential: Schedule V drugs have the lowest potential, while Schedule I drugs have no approved medical indications (ie Heroin)

Schedule II includes most opioids
Schedule III includes mixed acetaminophen-opioids and Tramadol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is the best test to order if you are concerned about diskitis?

A

ESR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What are some excitatory neuromediators? What about inhibitory neuromediators?

A
Excitatory neuromediators:
Glutamate
Aspartate
Substance P
Neurokinin
Bradykinin
CGRP
BDNF
Inhibitory neuromediators:
GABA
Glycine
Enkephalin
Beta-endorphin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Which part of the hypothalamus partly controls the sleep/wake patterns and may be altered in chronic pain?

A

The suprachiasmatic nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Where are opioid precursors and their respective peptides found in the brain?

A

Amygdala
Hypothalamus
PAG matter
Raphe Magnus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What nerve is involved in cubital tunnel syndrome?

A

Ulnar nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What two tendons are involved in de Quervain’s Tendosynovitis?

A

Extensor pollicis brevis

Abductor pollicis longus

52
Q

Describe the epidemiology and clinical features of CRPS. What is the difference between Type I and Type II? What is the most common sign and symptoms? What part of the body are the worst complications of CRPS seen?

A

Epidemiology

  • Average age is in the 40s
  • Women 3x than men

Clinical features

  • Pain (spontaneous, burning, hyperalgesia, allodynia)
  • Vasomotor changes - dilated (red) vs constricted (white)
  • Sudomotor changes - increased (wet) vs decreased (dry)
  • Edema
  • Trophic changes (hair and nails)

Type I - no demonstrable nerve injury
Type II - known peripheral nerve injury

Worst symptoms are seen in the lower extremities

Most common sign = allodynia
Most common symptoms = decrease range of motion

53
Q

What is the target for a stellate ganglion block? What is it used for? What are some known side effects?

A

Target is the transverse process of C6 (Chassaignac’s Tubercle)
- However the stellate ganglion itself actually lies anterior to the neck of the first rib and the transverse process of the C7 vertebra

Used for upper extremity and truncal neuropathic pain and CRPS

Can cause Horner’s syndrome (ptosis, miosis, and enopthalmos)

Can cause recurrent laryngeal nerve paralysis or even phrenic paralysis

54
Q

What is the target for a celiac plexus block? What organs does it cover? What are known side effects?

A

Target is the L1 or L2 vertebral level

Covers the pancreas, liver, gallbladder, omentum/mesentery, and the GI tract from stomach to transverse colon

Known to cause orthostatic hypotension and increased gastric motility (diarrhea)

55
Q

What is the target for lumbar sympathetic block? What is it used for?

A

Target is the L3 or L4 vertebral level

Used for lower extremity neuropathic pain and CRPS

56
Q

What is the target for a superior hypogastric block? What is it used for?

A

Target is the L5 vertebral level

Used for chronic pelvic pain

57
Q

Describe the innervation of vertebral facet joints.

A

Each individual facet joint is innervated by medial branches from that level and from the level above

58
Q

Describe the origin of both the greater and lesser occipital nerves.

A

Greater occipital nerve = dorsal rami of C2

Lesser occipital nerve = ventral rami of C2 and C3

59
Q

Describe some characteristics of phantom limb pain.

A

Pain is present in 60-80% of amputees

  • Severe pain in 5-10% of cases
  • Pain usually within the first week after amputation for vascular causes; much later (years) for other causes
  • Patients who develop early pain are more likely to suffer from long-lasting pain
  • Pain is usually intermittent and frequency/intensity tend to decline over time

The sensation is more vivid in the distal extremity
- Limb sensations “telescope” with time - the proximal part of the limb disappears first

Not reliably prevented with epidural blockade

Equal prevalence between men and women

Preamputation pain increases the risk of phantom pain

60
Q

Describe the innervation of the sacro-iliac joint.

A

L4 medial branch, L5 dorsal ramus, S1-3 lateral branches

61
Q

Which nerve is most commonly injured during a procedure in the lithotomy position?

A

The common peroneal nerve

62
Q

What is meralgia parasthetica? How does it present? What is the cause?

A

Meralgia parasthetica is numbness and pain in the anterolateral thigh.

It is caused by entrapment of the lateral cutaneous femoral nerve by the inguinal ligament or fascia lata.

63
Q

Describe gate theory.

A

Stimulation of A-beta fibers inhibits the firing of dorsal horn neurons in lamina V by activating inhibitory interneurons in lamina II

64
Q

Describe the 3 main patterns of cancer pain.

A

Incident pain

Spontaneous pain

End of dose pain

65
Q

What are the landmarks of the piriformis muscle? Describe piriformis syndrome.

A

The piriformis muscle extends from the anterior sacrum to the greater trochanter
- Responsible for lateral rotation and hip abduction

Piriformis syndrome presents with sciatic-like pain

  • Worse pain with sitting
  • Due to pressure on the passing sciatic nerve by the piriformis muslce
  • Positive piriformis stretch sign (pain with flexion, adduction, and internal rotation)
66
Q

What muscles make up the pelvic floor?

A

Obturator internus
Piriformis
Coccygeus
Levator ani

67
Q

Describe the signs of C5 root pathology.

A

Pain in neck, shoulder, anterolateral arm

Numbness in the deltoid area

Weakness of deltoid and biceps

Abnormal biceps reflex

68
Q

Describe the signs of C6 root pathology.

A

Pain in neck, shoulder, lateral arm

Numbness in dorsal thumb and index finger

Weakness of biceps, wrist extension

Abnormal brachioradialis reflex

69
Q

Describe the signs of C7 root pathology.

A

Pain in neck, shoulder, lateral arm, and forearm

Numbness in index/middle finger, dorsum of hand

Weakness of the triceps

Abnormal triceps reflex

70
Q

Describe the signs of L4 root pathology.

A

Pain in the back, thigh, and shin

Numbness in the medial shin

Weakness with foot dorsiflexion

Abnormal knee reflex

71
Q

Describe the signs of L5 root pathology.

A

Pain in back, posterior thigh

Numbness on the top of foot

Weakness of the extensor hallicus longus

72
Q

Describe the signs of S1 root patholgy

A

Pain the back and calf

Numbness of the lateral foot

Weakness of foot plantar flexion

Abnormal ankle reflex (not always consistent)

73
Q

Describe Spurling’s Test.

A

A test for cervical radiculopathy

Neck is bent laterally towards the painful side
Axial load is added in line with the spine

Positive test is radiating pain in the normal distribution

74
Q

When exposed to a local anesthetic, what is the order of the loss of nerve function?

A
  1. Pain
  2. Temperature
  3. Touch
  4. Proprioception
  5. Skeletal muscle tone
75
Q

How do triptans work to help control migraines?

A

Stimulate 5-HT1B receptors located on cranial blood vessels causing vasoconstriction

Stimulate 5-HT1D receptors located predominantly on trigeminal nociceptors, inhibiting nociceptive transmission from pain-sensitive meningeal structures

76
Q

How does propanolol work to help treat migraines?

A

Inhibits nitric oxide production
Antagonizes 5-HT1A and 5-HT2B receptors
Stabilizes membranes via inhibition of Glutamate receptors
Inhibits norepinephrine release

77
Q

What kind of movements/maneuvers can improve the pain associated with spinal stenosis?

A

Sitting, stooping forward (walking uphill), and forward flexion all help decrease pain because they decrease the effective degree of stenosis

78
Q

How do alpha-2 agonists (clonidine and dexmedetomodine) work?

A

Act in both the CNS and peripherally
Alter potassium and calcium conductance
Decrease neurotransmitter release presynaptically
Hyperpolarize the neuron postsynaptically, making it less likely to fire

79
Q

What medications are commonly found in EMLA creams?

A

EMLA creams (eutectic mixtures of local anesthetics) can contain medications such as lidocaine, prilocaine, and/or tetracaine

80
Q

Define the following types of pain: nociceptive, inflammatory, neuropathic, and functional

A

Nociceptive pain - adaptive transient pain in response to noxious stimuli

Inflammatory pain - transient pain hypersensitivity in response to tissue damage

Neuropathic pain - transient pain hypersensitivity in response to nerve damage

Functional pain - hypersensitivity in response to abnormal central input processing

81
Q

Describe the motor and sensory innervation of the brachial plexus.

A

Axillary nerve

  • motor to deltoid
  • sensation to lateral arm

Musculocutaneous nerve

  • motor to biceps
  • sensation to lateral forearm

Radial nerve

  • motor to wrist/thumb extension
  • sensation between thumb and index finger

Median nerve

  • motor for opposition/adduction of thumb
  • sensation of index finger

Ulnar nerve

  • motor for pinky abduction
  • sensation of pinky
82
Q

What is the difference between dermatomal pain, myotomal pain, and sclerotomal pain?

A

Dermatomal pain - pain in the distribution of a single nerve root innervating a specific area of skin

Myotomal pain - pain in the distribution of a group of muscles innervated by a single nerve root

Sclerotomal pain - pain emanating from an area of bone or fascia supplied by a single nerve root

83
Q

Describe the innervation of the intervertebral disk. What is it’s blood supply?

A

Innervated by nerves that accompany the anterior and posterior longitudinal ligaments are are derived from the lumbar sympathetic trunks:

  • sinuvertebral nerve
  • grey rami communicantes
  • lumbar ventral rami

Blood supplied by the lumbar artery

84
Q

What is the mechanism of epidural steroid injections?

A

Steroids decrease inflammation by inhibiting phospholipase A2, thus inhibiting the formation of arachidonic acid, prostaglandins, and leukotrienes
- By restricting the formation of prostaglandins they may decrease sensitization of the dorsal horn neurons

Steroids may reduce inflammatory edema around the inflamed nerve root and improve microcirculation

They block the conduction of nociceptive C fibers

85
Q

Describe the differences between alcohol and phenol when used for chemical neurolysis. How long does chemical neurolysis typically last?

A

Alcohol

  • painful
  • hypobaric
  • immediate onset
  • full effect in 3-5 days

Phenol

  • painless
  • hyperbaric
  • delayed onset (15 min)
  • full effect in 1 day
  • higher risk of neuroma

Chemical neurolysis typically last about 4 months

86
Q

What are the natural opioids? Semisynthetic? Synthetic?

A

Natural opioids = morphine and codeine

Semisynthetic opioids = heroin, hydrocodone, hydromorphone, oxycodone, oxymorphone, buprenorphine

Synthetic opioids = meperidine, methadone, fentanil, propoxyphene

87
Q

What are some important characteristics of morphine?

A

Conjugated in the liver and excreted by the kidneys

Two metabolites

  • M6G is an active metabolite with analgesic properties
  • M3G can cause CNS activation (myoclonus and seizures) if it accumulates, often in patients with renal failure
88
Q

What are some important characteristics of codeine?

A

A prodrug that is converted to morphine and slightly to hydrocodone

About 10% of people are poor metabolizers of codeine, resulting in variable relief

89
Q

What are some important characteristics of buprenorphine?

A

A mixed agonist-antagonist
- partial mew agonist, kappa antagonist

Slow dissociation from mew receptor and prolonged effect are why it is used for treatment of opioid dependence

90
Q

What are some important characteristics of Hydrocodone?

A

Most prescribed opioid in the USA

Often paired with acetaminophen

Metabolized to hydromorphone

91
Q

What are some important characteristics of oxycodone?

A

Primarily mew selective

Metabolized to oxymorphone

92
Q

What are some important characteristics of methadone?

A

Multiple mechanisms:

  • mew and delta opioid agonist
  • NMDA antagonist
  • norepinephrine and serotonin reuptake inhibitor

Has very variable oral bioavailability

Can interact with many common medications

Side effects can outlast the analgesic effects

Can prolong QT interval

93
Q

What are some important characteristics of meperidine?

A

Similar structure to atropine - can cause tachycardia

Metabolized to normeperidine, which can cause seizures

Should only be used for acute pain

94
Q

What are some important characteristics of tramadol?

A

Multiple mechanisms:

  • weak mew agonist
  • inhibits norepinephrine and serotonin reuptake
  • blocks nicotinic and muscarinic receptors
  • inhibits NMDA receptors

Can cause serotonin syndrome when mixed with SSRIs or TCAs

95
Q

What is the mechanism of Gabapentin and Lyrica?

A

Alteration of voltage-gated calcium channels by binding to the alpha-2-delta subunit

96
Q

What must be proven for a successful malpractice suit?

A

The patient/plaintiff must prove:

  1. Duty - the physician owed the patient a duty
  2. Breach of duty - physician failure to fulfill duty
  3. Causation - a close causal relation between physician’s act and the resultant injury
  4. Damages - actual damages that occurred
97
Q

How can you distinguish between medial and lateral epicondylitis?

A

With lateral epicondylitis, pain is increased with resisted wrist extension

With medial epicondylitis, pain is increased with resisted wrist flexion

98
Q

Via radiographic screening, what is the prevalence of lumbar spondylosis? What about if its based on diagnostic blocks?

A

6% based on radiographic screening

15-45% based on diagnostic blocks

99
Q

Technically, what is the first line agent for medical treatment of osteoarthritis?

A

Tylenol because OA is thought to be primarily non-inflammatory

However, NSAIDs have shown benefit as well

100
Q

What is the blood supply of the spinal cord?

A

2 posterior spinal arteries and 1 anterior spinal artery

  • Blood vessels arise from the segmental arteries of the aorta and from branches of the subclavian, vertebral arteries, and internal iliac arteries
  • Anterior spinal artery responsible for about 80% of blood flow
  • The largest feeder of the anterior spinal artery is the artery of Adamkiewicz that originates from between T8 and L3
101
Q

What is the normal anteroposterior diameter of the spinal canal? What is considered relative stenosis? What is considered absolute stenosis?

A

Normal diameter is more than 12 mm

Relative stenosis is less than 10 mm

Absolute stenosis is less than 8 mm

102
Q

Define neuropraxia.

A

Neuropraxia is nerve damage without any
disruption of the myelin sheath
- There is an interruption in conduction of nerve impulses
- There is a transient loss of motor conduction
- Little to no sensory conduction is affected

103
Q

Describe the dermatomal distribution of the lumbar and sacral nerves.

A

L1 - Upper thigh and groin

L2 - Mid anterior thigh

L3 - Medial femoral condyle

L4 - Medial malleolus

L5 - Top of the foot

S1 - Lateral heel

S2 - Medial popliteal fossa

104
Q

How many different types of voltage-gated sodium channels have been identified? Which seems to have a role in pain pathways?

A

9 types of sodium channels

Na-1.9 seems to have a specialized role in the pain pathway

105
Q

What are the most important substances found in the descending inhibitory pathways of the CNS?

A

Serotonin and Norepinephrine

106
Q

What are the diagnostic criteria for fibromyalgia? How is it characterized? How is sleep affected?

A

Diagnostic criteria:
1. Chronic widespread pain (CWP) defined as pain in all four quadrants of the body and the axial skeleton for at least 3 months
2. The finding of pain by 4-kg pressure on digital palpation of at least 11 of 18 defined tender
points

Characterized as primary or secondary:

  1. Primary - when work-up reveals no underlying cause
  2. Secondary - when some form of inflammatory or other pain condition is also diagnosed
    - Fibromyalgia symptoms generally do not resolve even with resolution of rheumatologic disease

Effects on sleep:

  • pts awaken feeling stiff, sluggish, and unrefreshed
  • pts commonly awaken after a few hours of sleep (mid-insomnia) and are unable to sleep again until near morning (terminal insomnia)
  • have no trouble napping during the day
107
Q

What are the characteristic differences between large-fiber neuropathy and small-fiber neuropathy?

A

Large-fiber neuropathy leads to weakness, numbness, tingling, and loss of balance

Small-fiber neuropathy leads to pain, anesthesia, and autonomic dysfunction

108
Q

What is intrathecal baclofen used for? What are the signs of overdose? What are the signs of withdrawal?

A

IT baclofen is used for antispasticity and muscle relaxation

Overdose symptoms include drowsiness, weakness, hypotonia, and respiratory depression

Withdrawal symptoms include diaphoresis, hyperthermia, hypotension, AMS, pruritis, and increased muscle tone
- Can be fatal

109
Q

What is the concern regarding cervical transforaminal epidural injections?

A

The vertebral artery lies in the anterior neuroforamen

110
Q

Why is fentanyl an ideal choice for transdermal and transmucosal administration?

A

High lipid solubility
Low molecular weight
High potency

111
Q

What are the main parts of the opioid risk tool (ORT)?

A

Age

Personal and family history of substance abuse

History of sexual abuse

Presence of depression, ADD, OCD, bipolar, or schizophrenia

112
Q

What is unique about clonazepam?

A

Clonazepam (Klonopin) binds to the Gaba-B receptor (unlike other benzos that bind to the Gaba-A receptor)

Used for neuropathic pain and muscle relaxation

113
Q

Describe “Weaver’s bottom”

A

Ischial bursitis

Pain when sitting which goes away upon standing or lying on contralateral side
- pain promptly returns upon resuming a seated position

On physical examination, tenderness is evoked with palpation over the ischiogluteal bursa

114
Q

What temperature range should be used to test warm temperature sensation? What about cold temperature sensation?

A

Warm temperature = 40 to 45 Celsius

Cold temperature = 5 to 10 Celsius

115
Q

What finding on EMG/NCS can help differentiate between tumor-induced brachial plexopathy or radiation induced brachial plexopathy?

A

Presence of myokymia (continuous but brief involuntary muscle twitching that gives the appearance of wormlike rippling of the muscle) indicates radiation induced cause

116
Q

What is the conversion from oral morphine to fentanyl patch?

A

Divide by 3

ie. 75 mg oral morphine daily to 25 mcg Fentanyl patch

117
Q

What is the difference between spondylosis, spondylolysis, and spondylolisthesis?

A

Spondylosis = degeneration of the spine

Spondylolysis = fracture of the pars interarticularis

Spondylolisthesis = slippage of one vertebral body out of alignment

118
Q

How does anterior spinal artery syndrome present?

A

Abrupt motor loss

Sphincter disturbance

Preservation of sensation to light touch but loss of pain and temperature.

119
Q

What is the most common organism that causes epidural abscess after a procedure?

A

Staphylococcus aureus

120
Q

What is unique about the pathophysiology of sickle cell disease pain?

A

It involves a combination of ischemic tissue damage and secondary inflammatory response

121
Q

Describe the three types of pain seen in spinal cord injury.

A

Above-level pain - includes pain caused by compressive mononeuropathies (particularly carpal tunnel syndrome) and CRPS

Below-level pain - central pain caused by the spinal cord trauma

At-level pain - may have both peripheral (nerve root) and central (spinal cord) components that are difficult to separate

122
Q

What is Ziconotide?

A

Derived from the toxin of the cone snail Conus magus

A neuronal-specific calcium-channel blocker that acts by blocking N-type, voltage-sensitive calcium channels

Must be administered intrathecally

Common side effects are dizziness, nausea, confusion, and headache
- Severe but rare side effects are hallucinations and suicidal ideation

123
Q

What is meant by “whiplash”? What muscles are involved?

A

“whiplash” describes the resultant injury caused by an abrupt hyperextension of the neck from an indirect force

Muscles involved:

  • Sternocleidomastoid
  • Longus colli muscle
  • Scalenes
124
Q

Describe the system that rates drugs based on their safety for use during pregnancy.

A

Category A: animal studies and controlled human studies indicate no apparent risk to fetus and possibility of harm to the fetus seems remote
- multivitamins

Category B: animal studies do indicate a risk, but well controlled human studies have not demonstrated a risk
- acetaminophen, most opioids, ibuprofen, caffeine

Category C: animal studies indicate risk, but no controlled human studies have been done
- aspirin, ketorolac, gabapentin, triptans

Category D: positive evidence of human fetal risk, but in certain circumstances, the benefits of the drug may outweigh the risks involved
- amitriptyline, benzos, phenytoin, valproate

Category X: positive evidence of significant fetal risk, and the risk clearly outweighs any possible benefit
- ergots

125
Q

What is the difference between impairment, disability, and handicap?

A

Impairment refers to a problem with a structure or organ of the body
- ie. spinal cord injury

Disability is a functional limitation with regard to a particular activity
- ie. inability to walk due to spinal cord injury

Handicap refers to a disadvantage in filling a role in life relative to a peer group
- ie. inability to work due to disability from spinal cord injury

126
Q

What is the difference between McKenzie method exercises and Williams method exercises?

A

McKenzie method exercises are spinal extension exercises used for disk herniations and radiculopathy

Williams method exercises are flexion based exercises used for stenosis

127
Q

What enzyme is responsible for metabolism of fentanyl and methadone?

A

CP450 CYP3A4