Nerve and Pain Flashcards
(99 cards)
1
Q
You are performing radiosurgery on a patient with left medically-refractory, lancinating ear and throat pain triggered by eating and drinking. Which figure shows the most optimal location of the radiation target?
A. Figure 4
B. Figure 3
C. Figure 2
D. Figure 5
E. Figure 1
A
C. Figure 2
2
Q
A 65-year-old man is seen for continued left medial hand pain after a failed submuscular ulnar nerve transposition procedure two months ago. Upon re-evaluation, new left ptosis and miosis is observed. What is the most likely diagnosis?
A. Pancoast Tumor
B. Ulnar nerve injury at an elbow level
C. Parsonage-Turner syndrome of the medial cord
D. Raeder’s paratrigeminal neuralgia
E. Thoracic outlet syndrome
A
A. Pancoast Tumor
3
Q
You are seeing a new patient with a spinal infusion pump in the Emergency Room. They report having had a pump refill at an outside institution earlier that day. No medical records are available for this patient. They are complaining of severe pain, diarrhea, nausea, and a sensation of skin crawling. On examination they show agitation, tachycardia, and vomiting. What clinical syndrome do you suspect?
A. Opioid withdrawal
B. Baclofen overdose
C. Clonidine withdrawal
D. Bupivacaine overdose
E. Ziconotide withdrawal
A
A. Opioid withdrawal
4
Q
A 48-year-old man who has been managed on a stable dose of intrathecal morphine presents with sudden onset altered mental status, sweating, severe pain, and diarrhea. His airway and breathing are stable. What is the best initial diagnostic workup at this point?
A. Head CT
B. Assessment by the Gastroenterology service
C. Plain X-rays of the pump system
D. Blood and urine cultures
E. Assessment by the Addiction Medicine service
A
C. Plain X-rays of the pump system
5
Q
You are seeing a patient with neuropathic lower extremity pain. On examination, light touch provokes severe burning pain on the dorsum of the foot. What is this phenomenon called?
A. Paresthesia
B. Hyperpathia
C. Tinel sign
D. Allodynia
E. Mechanical hyperalgesia
A
D. Allodynia
6
Q
You are seeing a patient with neuropathic lower extremity pain. On examination, repetitive pinprick provokes increasingly severe burning pain on the dorsum of the foot. This phenomenon is called:
A. Allodynia
B. Hyperpathia
C. Paresthesia
D. Tinel sign
E. Mechanical hyperalgesia
A
B. Hyperpathia
7
Q
You are performing a radial to axillary nerve transfer for a patient who sustained a C5 nerve root avulsion injury 3 months previously. You have decided to utilize a posterior approach for this nerve transfer. What two muscles are separated to access the donor nerve?
A. Biceps and brachioradialis
B. Deltoid and biceps
C. Biceps and lateral head of triceps
D. Biceps and pectoralis major
E. Long and lateral heads of the triceps
A
E. Long and lateral heads of the triceps
8
Q
What is one of the best ways to ascertain that ulnar nerve compression is distal (at the wrist) and not proximal (at the elbow)?
A. Test ulnar sensation on the dorsal surface of the hand
B. Test ulnar sensation on the 4th and 5th digits
C. Test the strength of the adductor pollicis muscle
D. Test the strength of the first dorsal interosseous muscle
E. Test the strength of the abductor digiti minimi muscle
A
A. Test ulnar sensation on the dorsal surface of the hand
9
Q
Anterior interosseous neuropathy causes weakness in the flexor pollicis longus, flexor digitorum profundus 1, and which muscle?
A. Opponens pollicis
B. First dorsal interosseous
C. Abductor pollicis brevis
D. Pronator quadratus
E. Pronator teres
A
D. Pronator quadratus
10
Q
For which aspect of pain is the dorsal anterior cingulate cortex (dACC) responsible?
A. Neurogenic
B. Somatosensory
C. Psychosomatic
D. Nociceptive
E. Affective
A
E. Affective
11
Q
A 16-year-old female presents with a sharp laceration to the posterior thigh. Examination shows complete lack of foot dorsiflexion and eversion, consistent with peroneal nerve injury. Imaging studies show no vascular compromise. What is the most appropriate initial management?
A. Superficial closure and nerve repair at 9 months
B. Acute wound exploration and nerve repair
C. Acute electrodiagnostic studies
D. Superficial closure and nerve repair at 3 months
E. Superficial closure and nerve repair at 1 month
A
B. Acute wound exploration and nerve repair
12
Q
A 43-year-old woman has been experiencing lancinating pain in the right occipital area for 8 months. She can trigger her pain by pushing on the back of her right scalp. Results of magnetic resonance imaging of the brain and spine are negative, and her neurologist has made the diagnosis of occipital neuralgia. The patient has exhausted numerous drug trials, but obtained 2 hours of pain relief with a right occipital nerve block. Which of the following would be the most appropriate treatment option for this patient?
A. High cervical spinal cord stimulation
B. Spinal infusion pump
C. Occipital nerve decompression
D. Caudalis dorsal root entry zone procedure
E. Motor cortex stimulation
A
C. Occipital nerve decompression
13
Q
You are referred a patient who developed severe leg pain, redness, and swelling after undergoing an open reduction and internal fixation of a tibial fracture. What diagnostic test would be most useful in distinguishing complex regional pain syndrome type 1 from type 2?
A. Electrodiagnostic studies of the lower extremities
B. Neuropsychological testing
C. Plain radiographs at the site of the fracture
D. Three phase bone scan of the whole body
E. Lumbar sympathetic block
A
A. Electrodiagnostic studies of the lower extremities
14
Q
What is a contraindication for bilateral percutaneous cordotomy in the treatment of chronic refractory pain?
A. Life expectancy of < 6 months
B. Severe pulmonary dysfunction
C. Pain associated with tumor compression of a peripheral nerve
D. Presence of mild dementia
E. Unilateral upper extremity pain
A
B. Severe pulmonary dysfunction
15
Q
You are examining your patient with a nerve injury and, when tapping along the course of the nerve at the site of injury, provoke an electrical sensation that radiates into the distribution of that nerve. What is this response called?
A. Tinel sign
B. Froment sign
C. Lhermitte sign
D. Wartenberg sign
E. Phalen sign
A
A. Tinel sign
16
Q
You are seeing an adult patient with a history of a painless left ankle mass, as indicated by the dotted outline and asterisk. Imaging is suggestive of a peripheral nerve sheath tumor. Within which nerve distribution do you suspect the nerve is located?
A. Sural nerve
B. Saphenous nerve
C. Tibial nerve
D. Deep peroneal nerve
E. Superficial peroneal nerve
A
C. Tibial nerve
17
Q
An 18-year-old patient has sustained a gunshot wound through the mid-thigh. At arrival to the emergency department, he is found to have intact pedal pulses but is unable to move his foot. The dorsum and sole of his foot have markedly decreased sensation. He can weakly flex his knee, although this is limited by pain. What is the most appropriate management of this suspected nerve injury?
A. Nerve exploration and possible repair at 1 year if no recovery.
B. Emergent nerve exploration and possible repair.
C. Nerve exploration and possible repair at 3 months if no recovery.
D. Nerve exploration and possible repair at 1 month if no recovery.
E. Emergent electrodiagnostic studies.
A
C. Nerve exploration and possible repair at 3 months if no recovery.
18
Q
You are seeing a patient with multiple stab wounds to the upper extremity. The patient has isolated deficits in finger extension and ulnar wrist extension. What is the most likely level of injury?
A. Ulnar nerve at the mid forearm
B. Median nerve at the elbow
C. Posterior interosseous nerve
D. Radial nerve at the distal forearm
E. Radial nerve at the elbow
A
C. Posterior interosseous nerve
19
Q
What is the first clinically important branch given off by the upper trunk of the brachial plexus?
A. Axillary nerve
B. Dorsal scapular nerve
C. Musculocutaneous nerve
D. Suprascapular nerve
E. Phrenic nerve
A
D. Suprascapular nerve
20
Q
You are seeing an adult patient who underwent left groin cannulation three weeks ago for cerebral angiography. They developed weakness and numbness of the left leg immediately afterwards. On your examination, they have weakness of left hip flexion and knee extension, and anteromedial leg numbness going down to the ankle. Electrodiagnostic studies reveal absent motor and sensory potentials in the femoral nerve, and MG sampling of the lumbar paraspinal muscles is normal. Where is the most likely site of injury?
A. Saphenous nerve
B. Femoral nerve, abdominal level
C. L4 nerve root
D. Femoral nerve, thigh level
E. Femoral nerve, inguinal ligament level
A
B. Femoral nerve, abdominal level
21
Q
You are seeing a patient with neuropathic upper extremity pain. She reports a spontaneous, pins-and-needles and crawling sensation in the skin of the affected area. This symptom is called:
A. Tinel sign
B. Allodynia
C. Hyperpathia
D. Paresthesia
E. Mechanical hyperalgesia
A
D. Paresthesia
22
Q
Pathology at the level of which structure is most likely to cause isolated, unilateral weakness of ankle dorsiflexion and inversion?
A. Tibial nerve
B. S1 nerve root
C. L5 nerve root
D. L4 nerve root
E. Peroneal nerve
A
C. L5 nerve root
23
Q
You are examining a patient who recently sustained multiple missile injuries to the upper extremity following an IED explosion. You suspect a brachial plexus injury. Motor testing of which of the following muscles would be most helpful in distinguishing a medial cord from a lower trunk injury?
A. First dorsal interosseous
B. Extensor digitorum communis
C. Abductor pollicis brevis
D. Flexor carpi ulnaris
E. Adductor pollicis
A
B. Extensor digitorum communis
24
Q
You are seeing an adult male patient who sustained a left-sided brachial plexus injury 3 months ago. On examination, he has weakness in the upper trunk muscles, and absent sensation in the C5 and C6 dermatomes. Electrodiagnostic studies reveal absent motor conduction in the musculocutaneous and axillary nerves. Sensory nerve action potentials in the axillary and musculocutaneous nerves are normal. What would be the most appropriate subsequent management step?
A. Upper trunk graft repair
B. Observation for an additional 3 months
C. Posterior cord graft repair
D. Axillary nerve neurolysis
E. Nerve transfer
A
E. Nerve transfer
25
Examination of which of the following movements is most helpful in distinguishing an L4 radiculopathy from a femoral neuropathy?
A. Knee extension
B. Hip flexion
C. Ankle plantar flexion
D. Thigh adduction
E. Knee flexion
B. Hip flexion
26
Which cannabinoid is thought to be most effective at treating pain?
A. Cannabicyclol (CBL)
B. Tetrahydrocannabinol (THC)
C. Cannabinol (CBN)
D. Cannabidiol (CBD)
E. Anandamide (AEA)
D. Cannabidiol (CBD)
27
A diabetic patient with known peripheral vascular disease undergoes an anterior cervical discectomy at C4-5. The operative course is unremarkable; however, in the recovery room, the patient is noted to have decreased sensation in the 4th and 5th digits of the left hand and decreased grip. What is the MOST likely diagnosis?
A. Brachial plexus stretch injury
B. Positioning nerve injury
C. Surgical trauma
D. Residual muscle relaxation
E. Embolic stroke
B. Positioning nerve injury
28
A patient sustains an accessory nerve injury during a lymph node biopsy. The biopsy incision is indicated by the dotted line in the images. Which of the following incisions permits the most effective exposure for assessment and possible repair of this nerve?
A. Figure 2
B. Figure 1
C. Figure 3
D. Figure 5
E. Figure 4
B. Figure 1
29
You are seeing a patient complaining of problems in her hand. You suspect that the patient has anterior interosseous neuropathy. In what pair of muscles would you expect to find weakness?
A. Flexor pollicis longus and flexor digitorum profundus 1
B. Flexor digitorum superficialis and flexor digitorum profundus
C. Pronator teres and pronator quadratus
D. First lumbrical and second lumbrical
E. Opponens pollicis and abductor pollicis brevis
A. Flexor pollicis longus and flexor digitorum profundus 1
30
Which of the following muscles is innervated by the median nerve?
A. Flexor carpi radialis
B. Lumbrical IV
C. Flexor digitorum profundus IV
D. Supinator
E. Adductor pollicis
A. Flexor carpi radialis
31
A 45-year-old woman with colon cancer presents with severe bilateral pain in her abdomen and pelvis due to multiple metastases. Although her pain has been responsive to oral narcotics, escalating doses have given her unacceptable sedating side effects. Which of the following interventions would be MOST appropriate in this setting?
A. Spinal cord stimulation trial
B. Dorsal root entry zone procedure
C. Oral buprenorphine trial
D. Intrathecal morphine trial
E. Percutaneous cordotomy
D. Intrathecal morphine trial
32
Injury to the suprascapular nerve results in which of the following neurological deficits?
A. Weakness of external shoulder rotation, numbness of lateral shoulder
B. Weakness of shoulder circumduction, numbness of posterior shoulder
C. Weakness of scapular rotation, weakness of scapular elevation
D. Weakness of shoulder abduction, weakness of external shoulder rotation
E. Weakness of internal shoulder rotation, numbness of anterior shoulder
D. Weakness of shoulder abduction, weakness of external shoulder rotation
33
What condition is present when reducing a drug effect results in a withdrawal syndrome?
A. Addiction
B. Use disorder
C. Habituation
D. Dependence
E. Tolerance
D. Dependence
34
Which of the major nerves arising from the brachial plexus has the worst prognosis for return of motor function following injury?
A. Median
B. Axillary
C. Musculocutaneous
D. Radial
E. Ulnar
E. Ulnar
35
You are operating on a patient with a nerve sheath tumor that you suspect is a benign schwannoma of the ulnar nerve. After initial exposure and dissection of the lesion, you discover that the tumor is securely attached to the nerve by a pair of fascicles as marked with asterisks in Figure 1. What is the most appropriate maneuver at this point?
A. Perform an internal debulking of the lesion
B. Divide the fascicles and remove the lesion
C. Biopsy the lesion for frozen and permanent sections and close
D. Excise the lesion and nerve and perform a graft repair of the nerve
E. Leave the tumor and fascicles alone and close
B. Divide the fascicles and remove the lesion
36
You are operating on a patient with neurofibromatosis-1 that you suspect has a benign neurofibroma of the sciatic nerve, and have performed the initial exposure of the lesion, shown in the figure. What is the most appropriate maneuver at this point?
A. Biopsy the lesion for frozen and permanent sections and close
B. Perform an internal debulking of lesion
C. Perform direct nerve stimulation to identify a safe zone to incise
D. Excise the lesion and perform a graft repair of the nerve
E. Perform en bloc excision of the tumor, nerve, and surrounding muscle
C. Perform direct nerve stimulation to identify a safe zone to incise
37
You are seeing a semi-professional baseball pitcher who has weakness of right shoulder external rotation and abduction. There is muscle atrophy as indicated by the arrows in the figure. You recommend a nerve decompression. Which of the following incisions would be the most appropriate for this patient?
A. Figure 2
B. Figure 4
C. Figure 1
D. Figure 5
E. Figure 3
D. Figure 5
38
A 30-year-old laborer presents with worsening burning arm pain radiating to the fourth and fifth digits with objective hand weakness, thenar and hypothenar wasting. These symptoms are exacerbated by extending his arm and turning the head towards the affected side. What is the most likely diagnosis?
A. Central cervical stenosis
B. Carpal tunnel syndrome
C. C7/T1 herniated disk
D. Neurogenic thoracic outlet syndrome
E. Pancoast tumor
D. Neurogenic thoracic outlet syndrome
39
A 50-year-old female patient presents with pelvic and leg pain. What are the paired structures indicated by the white arrows in the axial (Figure 1) and coronal (Figure 2) pelvic MRI?
A. Piriformis muscles
B. Sacrospinous ligaments
C. Pudendal nerves
D. Obturator nerves
E. Sciatic nerves
E. Sciatic nerves
40
Exploration of a peripheral nerve lesion reveals a traumatic neuroma-in-continuity. Which of the following intraoperative diagnostic modalities would be most useful in deciding whether to proceed with excision of the neuroma and perform a graft repair?
A. Nerve action potential recordings
B. Electromyography
C. Frozen section
D. Intraoperative MRI
E. High-resolution ultrasound
A. Nerve action potential recordings
41
You are performing a supraclavicular brachial plexus exploration. Which of the following incisions would be most appropriate?
A. Figure 5
B. Figure 4
C. Figure 1
D. Figure 3
E. Figure 2
D. Figure 3
42
You are revising an intrathecal catheter in a chronic pain patient who developed myelopathy after several years of benefit from a spinal infusion pump. You note the mass shown in the figure at the end of the catheter tip. Which of the following factors predisposes to the formation of these lesions?
A. Immunosuppressed status
B. Contaminated pump refills
C. Catheter fracture
D. High drug concentration
E. Catheter allergy
D. High drug concentration
43
A 30-year-old woman presents with right arm weakness that has progressed over a period of two months. MRI shows an enlarging mass associated within the median nerve (see figure). Biopsy demonstrates diffuse spindle-shaped cells with palisading hyperchromatic nuclei, frequent mitotic figures, necrosis, and loss of S-100 immunoreactivity. What is the best next step in management of this lesion?
A. Observation with surveillance imaging
B. Fractionated radiation therapy
C. Nerve-sparing excision
D. Limb amputation
E. En bloc excision with negative margins
E. En bloc excision with negative margins
44
A 25-year-old female presents with new onset weakness and vision difficulties which worsen as the day progresses. Nerve conduction and EMG testing shows improvement after the administration of edrophonium. What is the diagnosis?
A. Dermatomyositis
B. Guillain-Barré syndrome
C. Lambert-Eaton syndrome
D. Polymyositis
E. Myasthenia gravis
E. Myasthenia gravis
45
The McGill Pain Questionnaire Short Form (MPQ-SF) is a standardized pain assessment tool used for both clinical assessment and research. Which pain scoring system is a component of this assessment tool?
A. Wong-Baker FACES Pain Scale
B. Verbal Descriptor Scale (VDS)
C. Visual Analog Scale (VAS)
D. Color Scale for Pain
E. Numerical Rating Scale (NRS)
C. Visual Analog Scale (VAS)
46
In doing a nerve transfer procedure to recover elbow flexion, which of the following two nerves are coapted?
A. Radial and median
B. Radial and musculocutaneous
C. Ulnar and musculocutaneous
D. Ulnar and radial
E. Spinal accessory and suprascapular
C. Ulnar and musculocutaneous
47
A 48-year-old woman presents with a one-week history of progressive facial paresis, severe right ear pain, vertigo, imbalance, and hearing loss. Her past medical history is unremarkable. She has right beating nystagmus. Based on the MRI scan (figures), what is your diagnosis?
A. Vestibular schwannoma
B. Facial nerve schwannoma
C. Bell palsy
D. Facial nerve hemangioma
E. Zoster oticus
E. Zoster oticus
48
You are seeing a patient with new onset foot drop and dorsal foot numbness and pain. You obtain the following MRI. What is the most likely diagnosis?
A. Peroneal nerve schwannoma
B. Intraneural ganglion cyst
C. Tibulofibular joint dislocation
D. Tibial nerve hematoma
E. Baker cyst
B. Intraneural ganglion cyst
49
You are seeing an adult patient who is complaining of pain along the left medial knee and electrical shocks that shoot down the anteromedial left leg to the ankle. You suspect a nerve entrapment. Where is the most likely site of entrapment?
A. Obturator hiatus
B. Pelvic brim
C. Inferior patellar tendon
D. Inguinal ligament
E. Adductor canal
E. Adductor canal
50
For medically refractory postherpetic neuralgia of the trigeminal nerve, which of the following therapeutic interventions is most likely to alleviate pain?
A. Stereotactic radiosurgery of the trigeminal root
B. Percutaneous glycerol rhizolysis of the gasserian ganglion
C. Caudalis dorsal root entry zone procedure
D. Percutaneous radiofrequency lesion of the gasserian ganglion
E. Microvascular decompression of the trigeminal root
C. Caudalis dorsal root entry zone procedure
51
When a peripheral nerve is severed, the axon segments distal to the site of injury disappear over time, leading to the gradual loss of nerve conduction distal to the injury. What is this process called?
A. Demyelination
B. Denervational change
C. Axon sprouting
D. Wallerian degeneration
E. Exocytosis
D. Wallerian degeneration
52
A patient with chronic, medically-refractory migraine headaches has debilitating pain despite exhaustion of numerous preventative and abortive pharmacologic treatments. Which of the following would be the most appropriate intervention?
A. Intrathecal opiate trial
B. Sphenopalatine ganglion ablation
C. Cervical sympathectomy
D. Occipital nerve stimulator trial
E. Caudalis dorsal root entry zone procedure
D. Occipital nerve stimulator trial
53
Pain circuits within the substantia gelatinosa receive descending, inhibitory, serotonergic and adrenergic inputs from which brain structure?
A. Cuneate nucleus
B. Superior olivary nucleus
C. Red nucleus
D. Locus ceruleus
E. Interlaminar thalamic nucleus
D. Locus ceruleus
54
You are performing a percutaneous radiofrequency lesioning procedure in a patient with V3 distribution trigeminal neuralgia. After placing the electrode into the Gasserian ganglion and performing the test stimulation, the patient reports tingling in the V2 distribution. You wish to reposition the electrode to achieve V3 stimulation instead. In which direction will you move the electrode?
A. Inferior and anterior
B. Inferior and medial
C. Superior and lateral
D. Superior and posterior
E. Inferior and lateral
E. Inferior and lateral
54
You are considering a surgical procedure to treat your patient with medically refractory pelvic cancer pain. A lesion at which of the following locations would be most likely to effectively treat this pain syndrome?
A. 5
B. 2
C. 3
D. 1
E. 4
D. 1
55
You are operating on a patient with a sciatic nerve sheath tumor who presents with pain and no significant neurologic defect, and have performed the initial exposure of the lesion. You have incised the epineurium, but are unable to identify a distinct plane between tumor and nerve. What is the most appropriate maneuver at this point?
A. Excise the lesion and perform a graft repair of the nerve
B. Perform nerve action potential recordings
C. Biopsy the lesion for frozen and permanent sections and close
D. Perform en bloc excision of the tumor, nerve, and surrounding muscle
E. Perform a radical subtotal excision of the lesion
C. Biopsy the lesion for frozen and permanent sections and close
56
A 45-year-old male patient presents with right foot pain. What is the structure indicated in the MRI at the level of the popliteal fossa (Figure)?
A. Sciatic nerve
B. Common peroneal nerve
C. Popliteal vein
D. Tibial nerve
E. Popliteal artery
D. Tibial nerve
57
You are performing surgery on a patient with a suspected nerve entrapment, and discover that the nerve is severely narrowed (>50%) along the point of entrapment. What is the most appropriate treatment for this condition?
A. Neuroplasty
B. Nerve transposition
C. Internal neurolysis
D. Nerve transfer
E. Neurorrhaphy
C. Internal neurolysis
57
You are consulted to perform a sural nerve biopsy to evaluate a peripheral neuropathy. What would be the most appropriate incision for this patient?
A. Figure 5
B. Figure 4
C. Figure 3
D. Figure 1
E. Figure 2
E. Figure 2
57
You are examining your patient with suspected carpal tunnel syndrome and you ask that they aggressively flex their affected wrist. This maneuver reproduces their carpal tunnel symptoms. What is this response called?
A. Lhermitte sign
B. Phalen sign
C. Froment sign
D. Tinel sign
E. Wartenberg sign
B. Phalen sign
57
What type of pain related to spinal metastases is most responsive to radiation?
A. Mechanical pain
B. Nocturnal pain
C. Radicular pain
D. Neuropathic pain
B. Nocturnal pain
58
Which of the following diagrams most accurately depicts the typical course of the accessory nerve along the posterior triangle?
A. Figure 5
B. Figure 2
C. Figure 4
D. Figure 1
E. Figure 3
E. Figure 3
58
What characteristic of the pain associated with Type 2 trigeminal neuralgia differentiates it from Type 1 trigeminal neuralgia?
A. Pain that is constant
B. Pain that is bilateral
C. Pain that is of psychogenic origin
D. Pain that is associated with lacrimation and rhinorrhea
E. Pain that radiates to the occipital region
A. Pain that is constant
59
A 76-year-old female has a history of lancinating pain just below her right eye. You performed stereotactic radiosurgery on her 1 year ago, giving her excellent pain relief for 9 months. She now returns to you complaining of constant burning pain and diminished sensation where her lancinating pain used to be. What is this patient's most likely diagnosis at follow-up?
A. Anesthesia dolorosa
B. Symptomatic trigeminal neuralgia
C. Trigeminal neuropathic pain
D. Trigeminal deafferentation pain
E. Type 1 trigeminal neuralgia
D. Trigeminal deafferentation pain
60
A 38-year-old male experiences severe acute right arm pain and then develops severe deltoid weakness and mild biceps and triceps weakness. After 6 weeks, he seeks consultation. Axial MRI imaging at C4-5 and C5-6 are shown.
What is the next most appropriate step in management?
A. ACDF C4-5 and C5-6
B. Epidural steroid injection
C. CT myelogram
D. Cervical traction
E. EMG/NCS
E. EMG/NCS
61
You performed an uneventful supraclavicular brachial plexus exploration to remove an upper trunk schwannoma. Postoperatively, the patient has a new complaint of dyspnea on exertion. On examination, her vitals are normal at rest. On exertion, she experiences shortness of breath without tachycardia. She has full strength and sensation within an upper trunk distribution.
What would be the most appropriate initial diagnostic test to evaluate the etiology of her symptoms?
A. Brachial plexus MRI
B. Lower extremity DVT ultrasound
C. Chest X-ray
D. Thoracic outlet MRV
E. EMG/NCS
C. Chest X-ray
62
A patient presents 3 months after a motor vehicle accident with the following isolated injury to the right C5 nerve root.
What would be the most appropriate treatment?
A. Observation
B. Ulnar to musculocutaneous (Oberlin) nerve transfer
C. C5 to upper trunk graft repair
D. C5 nerve rootlet reimplantation
E. Accessory to suprascapular nerve transfer
E. Accessory to suprascapular nerve transfer
63
For what condition did the World Health Organization (WHO) treatment ladder originally describe the escalating use of pain medications?
A. Cancer pain
B. Complex regional pain syndrome
C. Trigeminal neuralgia
D. Postherpetic neuralgia
E. Intercostal neuralgia
A. Cancer pain
64
Which of the following neuropathic pain medications works by binding to voltage-gated calcium channels in neurons?
A. Gabapentin
B. Clonidine
C. Baclofen
D. Amitriptyline
E. Ketamine
A. Gabapentin
65
A 40-year-old female undergoes biopsy of an enlarged posterior cervical lymph node. In the immediate post-operative period, she is noted to have severe aching shoulder pain and loss of shoulder abduction above horizontal.
What is the most likely diagnosis?
A. Spinal accessory nerve injury
B. Thoracic outlet syndrome
C. Long thoracic nerve injury
D. Parsonage-Turner syndrome
E. Cervical disc herniation
A. Spinal accessory nerve injury
66
The trigeminal cistern is an important structure in percutaneous trigeminal procedures. Where is the trigeminal cistern located in relation to the gasserian ganglion?
A. Superolateral
B. Inferomedial
C. Posterior
D. Anterior
E. Inferolateral
C. Posterior
67
A 20-year-old man was thrown from his motorcycle, sustaining severe injury to his right shoulder, including fractures of the clavicle and scapula. He had no right radial pulse, and an infraclavicular and supraclavicular mass was noted. He was not moving his right arm. Angiography revealed a tear of the second segment of the axillary artery and the patient underwent emergent surgical exploration and vascular repair.
What neurosurgical procedure should be performed in a concurrent fashion?
A. Intraoperative nerve action potential recordings (NAPs) across the injured segments
B. Evaluation of the plexus at the operative site after vascular repair is complete, with repair of any disrupted elements
C. Evaluation of the plexus through the operative site, with identification and tagging of any disrupted elements
D. Wide and total exploration of the plexus when vascular repair is completed
E. No intervention or evaluation is indicated intraoperatively
C. Evaluation of the plexus through the operative site, with identification and tagging of any disrupted elements
67
You are seeing a patient with left leg pain and foraminal stenosis at four lumbar levels on the left side. You are considering decompressive surgery, but want to identify the symptomatic level(s) prior to operating.
Which procedure would be best suited to identify the nerve root(s) responsible for the pain?
A. Provocative discography
B. Selective nerve root block
C. Sacroiliac joint injection
D. Interlaminar epidural steroid injection
E. Facet joint injection
B. Selective nerve root block
68
A 60-year-old man presents with 3 months of worsening diffuse, severe, unremitting left upper extremity pain, paresthesias, and hand weakness.
Exam shows 4/5 weakness of hand muscles including abductor pollicis brevis and all intrinsics, scattered sensory loss on the ulnar side of the forearm, normal deep tendon reflexes, and no evidence of myelopathy. MRI of the cervical spine shows mild degenerative changes throughout the neck.
What imaging study would assist in the diagnosis?
A. Cervical spine flexion-extension x-rays
B. Scoliosis survey
C. Chest CT
D. Bone scan
E. Thermogram
C. Chest CT
69
Injury to the axillary nerve will result in a deficit in which of the following movements?
A. Elevation of the scapula
B. External rotation of the shoulder
C. Depression of the scapula
D. Abduction of the shoulder from 60° to 120°
E. Internal rotation of the shoulder
D. Abduction of the shoulder from 60° to 120°
70
The tumor represented in this photomicrograph most frequently occurs in association with what condition?
A. Sturge-Weber syndrome
B. Tuberous sclerosis
C. Neurofibromatosis-2
D. Von Hippel-Lindau syndrome
E. Turcot syndrome
C. Neurofibromatosis-2
71
A patient with a history of left trigeminal neuralgia has undergone a percutaneous radiofrequency rhizotomy, which gave her 2 years of pain relief. This was followed by stereotactic radiosurgery of the trigeminal nerve root, resulting in absence of her lancinating pain. She now has new left facial pain that is constant and aching. On examination, her left face is anesthetic to light touch and pinprick.
What is her diagnosis?
A. Anesthesia dolorosa
B. Trigeminal neuropathic pain
C. Trigeminal deafferentation pain
D. Symptomatic trigeminal neuralgia
E. Type 2 trigeminal neuralgia
A. Anesthesia dolorosa
72
A 45-year-old woman is referred with complaints of debilitating paroxysmal, lancinating pain involving the deep aspect of the left ear canal. Her neurological examination is normal. A CT scan of the brain and skull base along with an MRI of the brain are both normal. She has failed medical management of her condition.
Which of the following represents the BEST surgical treatment option?
A. Microvascular decompression of the trigeminal nerve
B. Removal of the styloid process
C. Intradural rhizotomy of the 9th and upper 1/3 of the 10th cranial nerves
D. Nucleus caudalis DREZ ablation
E. Intradural section of the nervus intermedius
E. Intradural section of the nervus intermedius
73
During an examination you ask your patient to squeeze their thumbs and fingers together tightly. During this maneuver you note an abnormality in the left hand seen in the figure. Weakness in which muscle is responsible for this finding?
A. Dorsal interosseous
B. Flexor pollicis longus
C. Adductor pollicis
D. Flexor digitorum profundus
E. Abductor pollicis brevis
Adductor pollicis This diagnostic sign is called Froment sign. It occurs when the patient is asked to adduct the thumb against resistance in the setting of weakness of the adductor pollicis muscle, typically in the setting of an ulnar neuropathy. When the patient adducts the thumb, the flexor pollicis longus muscle, which is innervated by the median nerve, flexes the distal phalanx to press the tip of the thumb against the hand as a compensatory maneuver. The flexor digitorum profundus flexes the distal phalanx of the 2-5th digits. The dorsal interossei spread the fingers away from the midline of the hand within the plane of the palm. The abductor pollicis brevis abducts the thumb away from the plane of the palm.
74
What is the most likely vessel to make pathological contact with the glossopharyngeal nerve causing glossopharyngeal neuralgia?
A. Posterior choroidal artery
B. Superior cerebellar artery
C. Basilar artery
D. Posterior cerebral artery
E. Posterior inferior cerebellar artery
Posterior inferior cerebellar artery Answer, posterior inferior cerebellar artery. The posterior inferior cerebellar artery (PICA) lies in close vicinity to the normal glossopharyngeal nerve, and has been shown on MRI studies to be most frequently associated with vascular compression of the glossopharyngeal nerve in the setting of glossopharyngeal neuralgia. Compression by the vertebral artery has also been reported, but is less common. The other listed vessels do not normally contribute to vascular compression of the glossopharyngeal nerve. The superior cerebellar artery (SCA) commonly compresses the trigeminal nerve in patients with trigeminal neuralgia. The anterior inferior cerebellar artery (AICA) commonly compresses the facial nerve in patients with hemifacial spasm.
75
A 25 year-old man presents with a flail, anesthetic arm after an industrial accident with closed injury to the brachial plexus. After 6 months, he has recovered shoulder, elbow, and wrist movement, but the hand remains flail. Examination shows the presence of ptosis and miosis ipsilateral to the injured arm. Electrodiagnostic studies show normal sensory nerve action potentials of the ulnar nerve. Where is the most likely injury?
A. Postganglionic injury of C7
B. Preganglionic injury of C7
C. Postganglionic injury of T1
D. Preganglionic injury of T1
E. Postganglionic injury of C8
Preganglionic injury of T1 Answer, preganglionic injury of T1. Ptosis and miosis indicate Horner's syndrome that is consistent with pre-ganglionic injury of T1. The sympathetic fibers to the eye travel along the T1 nerve root, and are susceptible to injury during T1 root avulsion. A preganglionic injury occurs between the dorsal root ganglion and the spinal cord, usually at the level of the spinal rootlets. Injury in this location tends to preserve the connections between the sensory axons in the peripheral nerves and their cell bodies, which reside in the dorsal root ganglion. Thus, electrodiagnostic studies will show normal sensory nerve action potentials. The arm will remain anesthetic in the affected distribution, however, because the sensory pathways never make it into the spinal cord due to the avulsed rootlets. In contrast, the peripheral motor axons do not maintain their connectivity with their cell bodies, as the alpha motor neurons reside in the ventral horn of the spinal cord. Thus, motor nerve conduction studies will be abnormal in the avulsed segments. Postganglionic nerve injuries affect both sensory and motor axons, so neither sensory nor motor nerve action potentials would be preserved in that case. C7 injury is inconsistent with loss of hand function.
76
You have performed a nerve biopsy on a patient with a suspected peripheral neuropathy. Congo Red staining reveals abnormal deposits in the tissue (Figure). What is the most likely diagnosis?
A. Small fiber neuropathy
B. Vasculitis
C. Amyloidosis
D. HIV neuropathy
E. Sarcoidosis
Amyloidosis Amyloidosis is a collection of disorders that involve the deposition of abnormally-folded proteins, called amyloid fibrils, in the affected tissues. There are hereditary and acquired variants. Peripheral nerve dysfunction can result when the disease occurs in the nerves. Although the presence of a peripheral neuropathy can be suggested on history, physical examination, and electrodiagnostic studies, the diagnosis of peripheral nerve amyloidosis is made on nerve biopsy. The amyloid deposits have a typical apple-green appearance on Congo red staining viewed with polarized light and a red appearance when viewed with unfiltered light. Nerve biopsy in the setting of vasculitis typically reveals an inflammatory infiltrate throughout the intraneural blood vessels. Nerve biopsy in the setting of sarcoidosis typically reveals epineurial granulomas. HIV neuropathy will often display viral inclusions, axon loss and/or marked CD8 lymphocytic infiltration in the specimen. Small fiber neuropathy typically is diagnosed by a paucity of small nerve fibers seen on skin biopsy.
77
An obese 65-year-old man presents with 1 week of progressive weakness, aching pain, and mild sensory loss in his right quadriceps. He has no back, groin, or radicular pain, nor history of recent trauma or anticoagulant use. Pulses are normal, as is lumbosacral MRI. What is the most effective initial test to assess this condition?
A. EMG/NCS of the leg
B. CT of the pelvis
C. Angiogram of the leg
D. MRI of the leg
E. Fasting blood sugar level
Fasting blood sugar level Answer, fasting blood sugar analysis. The patient has a femoral neuropathy. Considering the patient's age and history of rapid onset, weakness, atrophy, and dysesthetic pain, femoral neuropathy secondary to diabetes is a strong possibility. Diabetes can first present as an acute mononeuropathy, and the femoral nerve is the nerve most frequently affected and most seriously affected. Testing for diabetes with fasting blood sugar analysis is the most effective and efficient way to confirm the diagnosis. Normal MRI of the lumbar spine rules out a herniated disc. CT of the pelvis might be of value in detecting femoral nerve compression by a psoas hematoma if the patient were receiving anticoagulants and had concomitant back pain. EMG could be helpful, but denervation changes would not be evident this early. MRI of the leg is not sensitive for detecting femoral neuropathy. Femoral arteriography would show large vessel disease, but neuropathy is caused by small vessel disease, not well-visualized with arteriography.
78
You are treating a patient with chronic, medically-refractory low back pain. You decide to proceed with a trial of spinal cord stimulation. What would be the most appropriate spinal level for electrode placement to achieve the best stimulation coverage of the patient's painful area?
A. L5
B. L2
C. T11
D. C1
E. T9
T9 Answer, T9. Electrodes placed at this level typically provide excellent stimulation paresthesias to the low back, and lower extremity if desired. Placement at T11 is an excellent option for coverage of the lower extremity and foot. Stimulation of the lumbar roots below the cord (usually anything below L1) does not typically provide low back coverage. Placement of an electrode array at C1 can be effective for upper extremity symptoms, but does not do much for low back pain.
79
Which of the following analgesics works by binding to voltage gated sodium channels in nerve cells, thus preventing depolarization?
A. Ziconotide
B. Ibuprofen
C. Bupivacaine
D. Capsaicin
E. Fentanyl
Bupivacaine Answer, bupivacaine. This is an amino amide anesthetic commonly used for local anesthesia, epidural anesthesia, peripheral nerve blockade, and sympathetic blockade. It binds to voltage gated sodium channels in nerve cells, prevents depolarization, and thus prevents the transmission of a pain reponse. Bupivicaine may also be administered intrathecally, via a spinal infusion pump, for the treatment of chronic pain. It is commonly used intrathecally with an opioid, and sometimes clonidine as well. Capsaicin binds to spinal cord vanilloid (TRPV1) receptors, temporarily rendering the pain pathways nonfunctional (defunctionalization). Fentanyl binds the mu, delta, and/or kappa (as well as other) opioid receptors in the nervous system, with an especially high concentration of them located in the periaqueductal gray region of the brain. Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is effective for the reduction of inflammation and the treatment of modest nociceptive pain. Ziconotide binds to N-type voltage-gated calcium channel blocker in the spinal cord (and brain), and inhibits the release of nociceptive neurotransmitters such as glutamate and supstance P, thus decreasing pain levels.
80
A patient presents with chronic neuropathic leg pain two years following an L4-S1 laminectomy for spinal stenosis. A current lumbar spine MRI shows no stenosis or nerve root impingement. Flexion and extension x-rays show no evidence of instability. What is the most appropriate treatment at this time for his pain?
A. Spinal cord stimulator trial
B. Provocative lumbar discography
C. Sacroiliac joint injection
D. Radiofrequency facet denervation
E. Lumbar interbody fusion
Spinal cord stimulator trial Postlaminectomy (failed back surgery) syndrome with persistent neuropathic leg pain can be treated in a number of ways. For example, if imaging shows compression of the appropriate neural elements, then surgical decompression may be indicated. If imaging is unrevealing, then a more functional (i.e. non structural) approach would be appropriate. Spinal cord stimulation is an example of a good strategy in this case. A randomized, prospective clinical trial has demonstrated the efficacy of spinal cord stimulation for neuropathic leg pain following unsuccessful lumbar spine surgery. Sacroiliac joint injection and provocative discography are types of diagnostic injections used to work up low back pain. Radiofrequency facet denervation is an interventional pain procedure used to treat low back pain. A lumbar interbody fusion would not be expected to help neuropathic leg pain in the absence of a compressive lesion along an appropriate nerve root or roots.
81
You are considering performing a multilevel lumbar spinal fusion in a patient taking buprenorphine for opiate addiction. Which clinical effect of buprenorphine will most likely complicate the management of this patient?
A. Buprenorphine can block the analgesic effects of opioids
B. Buprenorphine can block the effects of inhalational anesthetics
C. Buprenorphine can cause seizures
D. Buprenorphine can impair rates of bone fusion
E. Buprenorphine can cause severe respiratory depression
Buprenorphine can block the analgesic effects of opioids Answer, buprenorphine can block the analgesic effects of opioids. Buprenorphine (Suboxone) is a semisynthetic opioid that acts as a partial mu opioid receptor agonist and antagonist at the kappa opioid receptor. The binding affinity of buprenorphine at the m-opioid receptor is 1000 times higher than morphine, and thus can block the pharmacologic effects of administered opiates. This is the mechanism by which buprenorphine treats opiate addiction. It binds to the opiate receptors (and prevents withdrawal symptoms), but prevents other opiates from binding and causing a "high". Postoperative opiates will therefore have significantly reduced analgesic effects in patients who are also taking buprenorphine, which can complicate acute postoperative pain management. The usual recommendation for chronic pain patients on high doses of buprenorphine about to undergo major surgery is therefore to discontinue its use 3 days prior to surgery. Buprenorphine does not cause seizures or respiratory depression, nor does it block the effects of inhalational agents. There is no evidence that buprenorphine affects bone fusion rates.
82
You are seeing an adult patient with a history of tarsal tunnel syndrome, who presents with plantar foot discomfort sparing the heel. You decide to decompress the nerve at its typical area of entrapment. Which of the following incisions would be most appropriate to do this?
A. Figure 1
B. Figure 4
C. Figure 5
D. Figure 2
E. Figure 3
Figure 5
83
You are seeing a patient who developed new lower extremity symptoms after a surgical procedure. It is now 1 month post-procedure. You are considering a sciatic nerve injury vs. an idiopathic lumbosacral plexopathy as the most likely diagnoses. EMG abnormalities in which muscle would suggest the latter diagnosis?
A. Semimembranosus
B. Short head of the biceps
C. Gastrocnemius
D. Anterior tibialis
E. Gluteus medius
Gluteus medius Answer, gluteus medius. This muscle is innervated by the superior gluteal nerve. If there are EMG abnormalities in this muscle, then that suggests the problem is more widespread than just the sciatic nerve, and would be consistent with a lumbosacral plexus lesion, idiopathic or otherwise. All of the other muscles are innervated by the sciatic nerve, and thus would not be helpful in this analysis.
84
What is the nerve that is compressed in tarsal tunnel syndrome?
A. Deep peroneal nerve
B. Saphenous nerve
C. Superficial peroneal nerve
D. Tibial nerve
E. Sural nerve
Tibial nerve Answer, tibial nerve. Compression of the tibial nerve by the lancinate ligament on the medial surface of the ankle, posterior to the medial malleolus can cause tarsal tunnel syndrome. This nerve entrapment typically results in plantar foot pain, usually sparing the heel (which is innervated by the calcaneal branch). In severe cases, the intrinsic muscles of the foot can be affected. The heel is spared since the calcaneal branches usually leave the tibial nerve proximal to the tarsal tunnel. The tibial nerve may also be compressed more distally along the tarsal tunnel as the nerve enters the plantar foot. Pain in the sural nerve distribution usually is found along the lateral heel and ankle, and along the lateral foot. Saphenous nerve pain usually is present in a narrow band along the anteromedial leg from the knee to the ankle. Superficial peroneal nerve pain is generally along the dorsum of the foot. Deep peroneal nerve pain is generally along the dorsal webspace between the first and second toes.
85
You have diagnosed your patient with a nerve entrapment and have decided to decompress the entrapped nerve. Which of the following procedures would be most appropriate for the majority of nerve entrapments?
A. Neuroplasty
B. Nerve transposition
C. Internal neurolysis
D. Nerve transfer
E. Neurorhaphy
Neuroplasty The circumferential dissection of a nerve from the surrounding tissues is called neuroplasty, also known as an external neurolysis. This procedure effectively treats most nerve entrapments, and is the initial operative maneuver prior to performing almost every nerve procedure. An internal neurolysis involves incising the epineurium, often multiple times in a circumferential fashion, to decompress scarring within the nerve itself. It is not routinely done for most nerve decompression procedures but can be a good technique for decompressing hourglass constrictions in the nerve or separating scarred fascicles from non-scarred fascicles for individual NAP testing. Nerve transposition involves moving the nerve from its native location to another location, generally to relieve tension on the nerve or to place it in a more favorable environment to allow healing. It is often done for the ulnar nerve, but is rarely performed for other entrapments. Nerve transfer involves harvesting a donor nerve that supplies a less important muscle, cutting the nerve, and transferring it to an injured donor nerve that supplies a more important muscle. Neurorrhaphy involves the repair of an injured nerve, with either direct coaptation, or repair with a graft or conduit.
86
A 35-year-old woman has been experiencing excruciating early morning headaches localized behind the right eye, associated with ptosis and ipsilateral nasal congestion, lasting approximately 20 minutes. These symptoms have been present intermittently for 10 days. She had experienced several similar episodes in the past, lasting 1 to 2 weeks, followed by a pain-free interval. What is the most effective treatment option to abort this patient's headache once it has begun?
A. Oral dexamethasone
B. Subcutaneous sumatriptan
C. Oral lithium
D. Intravenous fosphenytoin
E. Lying in bed in a dark, quiet room
Subcutaneous sumatriptan Answer, subcutaneous sumatriptan. This is the best treatment listed here to abort cluster headache. This disorder, which is more common in men, is a type of neurovascular headache, distinct from migraine, characterized by excruciating pain of relatively short duration. The episodes can occur daily or several times per day, often for weeks at a time. Then there may be weeks or months of a pain-free interval, followed by more "clusters" of headache episodes. The treatments for cluster headaches consist of "preventives", such as verapamil, lithium, and anticonvulsants, which are taken regularly to decrease the frequency and intensity of the headache episodes. Another form of treatment is the "abortives", which are intended to be taken once the headache starts. These can include injectable sumatriptan, inhaled oxygen, inhaled sumatriptan, and inhaled local anesthetics. The other listed options are not generally effective abortives for cluster headache.
87
Which characteristic best distinguishes malignant from benign nerve sheath tumors?
A. Central T2 hypointensity ("target sign") within the tumor
B. Intensity of contrast enhancement in the tumor
C. Extralesional T2 hyperintensity around the tumor
D. Location of the tumor
E. Cystic changes within the tumor
Extralesional T2 hyperintensity around the tumor Extralesional T2 hyperintensity tends to occur around malignant but not benign nerve sheath tumors. Both benign and malignant tumors can grow in any location where nerves are found and can display intense contrast enhancement. A “target sign” occurs when central necrosis and/or hemorrhage within the center of the tumor create an area of relative T2 hypointensity. This phenomenon occurs too infrequently to be considered a reliable sign to distinguish benign from malignant tumors. Cystic changes within the tumor can help distinguish malignant from benign neurofibromas, but cannot distinguish benign schwannomas from malignant tumors, as cystic degeneration is very common in benign schwannomas.
88
Which of the following structures represents a potential site of ulnar nerve entrapment?
A. Struther's ligament
B. Osborne's ligament
C. Bicipital aponeurosis
D. Supinator muscle
E. Pronator teres muscle
Osborne's ligament Answer, Osborne's ligament. This structure is also known as the flexor carpi ulnaris aponeurosis. This fascial band forms the roof of the cubital tunnel, just distal to the ulnar groove. As the ulnar nerve passes approaches the elbow joint, it passes under the Arcade of Struthers, which is actually a band of triceps muscle and/or tendinous fibers attaching to the medial intermuscular septum. Both of these structures can become sites of entrapment of the ulnar nerve, especially if the nerve is subjected to a transposition, whereupon the nerve can get kinked as it wraps around them. Passing the ulnar groove between the medial epicondyle and olecranon, the ulnar nerve then enters the cubital tunnel. This region is bordered by the heads of the flexor carpi ulnaris muscle and its superficial aponeurosis (Osborne's ligament) and deep fascia. The fascia here can be sufficiently tight to compress the ulnar nerve here, causing cubital tunnel syndrome. Struther's ligament connects the supracondylar spur and the medial epicondyle of the humerus, and, when present, represents a potential site of entrapment of the median nerve at the elbow. The bicipital aponeurosis, also called the lacertus fibrosis, is a tendinous band that originates along the biceps tendon, and covers the median nerve as it crosses into the antecubital fossa, where it can entrap that nerve. The supinator muscle is located in the proximal forearm, and it represents a potential site of entrapment for the radial nerve at that location. The pronator teres muscle represents a potential site of entrapment of the median nerve at a proximal forearm level. This condition is known as pronator teres syndrome, appropriately enough.
89
A grade of 4- on the Medical Research Council Muscle Grading Scale signifies which of the following?
A. Active movement with gravity eliminated
B. Normal strength
C. No muscle contraction
D. Active movement against gravity
E. Active movement against gravity with slight resistance
Active movement against gravity with slight resistance The Medical Research Council Muscle Grading was developed after WW I to allow the standardized assessment of motor function following peripheral nerve injury. It continues to be the most common method for grading muscle function today. The Scale is as follows: 0 No muscle contraction 1 Flicker of muscle contraction 2 Active movement with gravity eliminated 3 Active movement against gravity 4- Active movement against gravity with slight resistance 4 Active movement against gravity with modest resistance 4+ Active movement against gravity with almost full resistance 5 Normal strength
90
You have been treating a patient with low back pain with opiates for many years. His doses have been gradually increasing. Spinal imaging has shown no significant changes. More recently he reports that his pain has become progressively more severe, and increasing doses of opiates are associated with increased pain. What is this phenomenon called?
A. Malingering
B. Opioid-induced hyperalgesia
C. Conversion disorder
D. Opioid dependence
E. Opioid addiction
Opioid-induced hyperalgesia Answer, opioid-induced hyperalgesia. This phenomenon occurs when patients on chronic opioid medication develop worsening of their pain that paradoxically becomes less responsive to continued or even increased opioid dosing. Sometimes this condition can become apparent when the patient has extreme postoperative acute pain that does not respond to opioid therapy. These patients may report worsening of their chronic pain syndrome, and often report extreme sensitivity to otherwise minimally-noxious phenomena, such as blood draws, i.v. line placement, etc. The pathophysiology of this disorder is unknown, but is thought to be secondary to toxic alterations of the pain pathways by chronic opioid administration. The treatment usually consists of tapering the opioid medications and switching to nonnarcotic strategies. Opioid addiction describes a compulsive use of opioids, whereas opioid dependence is present when withdrawal occurs upon sudden opioid cessation. Malingering occurs when patients exaggerate or fabricate symptoms for secondary gain. Conversion disorder occurs when the patient has neurological symptoms and signs of psychogenic origin.
91
What is the BEST pain procedure for treating pelvic and/or rectal pain due to ovarian carcinoma?
A. Spinal cord stimulation
B. Sacral root stimulation
C. Punctate midline myelotomy
D. Dorsal root entry zone procedure
E. Sacral rhizotomy
Punctate midline myelotomy Answer, punctate midline myelotomy. This is an ablative procedure that holds great promise in relief of pelvic and visceral pain due its ability to disrupt the midline visceral pathway. Similar to cordotomy, the goal of this procedure is to interrupt the afferent visceral pain fibers of the midline dorsal column, which are thought to carry more nociceptive visceral information than the spinothalamic pathways. Typically, a 5mm deep and 1mm wide midline posterior punctate lesion is made with a needle or microdissector in the upper third of the thoracic spine. Spinal cord stimulation has no significant role in treatment of midline visceral pain of this nature. Similarly, sacral root stimulation or destruction are unlikely to be helpful, due to the diffuse, nociceptive nature of the pain. The dorsal root entry zone procedure is best suited for root avulsion pain syndromes, and is unlikely to have a beneficial effect in this patient.
92
The right obturator nerve is inadvertently sectioned sharply during a gynecologic procedure. What is the best management of this injury?
A. No repair, physical therapy
B. Immediate tension-free end-to-end anastomosis
C. Immediate repair with graft
D. Delayed repair with graft
E. Delayed tension-free end-to-end anastomosis
Immediate tension-free end-to-end anastomosis Answer, immediate tension-free end-to-end anastomosis. Ideally, the management of an acute iatrogenic sharp nerve section is immediate tension-free end-to-end anastomosis. Unfortunately many of these injuries do not reach surgical attention until long after the injury, making direct repair impossible due to nerve retraction. Bluntly severed or cauterized nerves must be repaired in a delayed fashion. Grafts may be used in delayed repairs and if there is not enough slack in a primarily injured nerve.
93
Which of the following analgesics works by binding to spinal cord vanilloid (TRVP1) receptors, thus causing prolonged depolarization and defunctionalization of the pain pathways?
A. Bupivacaine
B. Fentanyl
C. Ziconotide
D. Ibuprofen
E. Capsaicin
Capsaicin
Answer, capsaicin. This is an analgesic often administered topically for the treatment of chronic neuropathic pain. It is derived from the active ingredient in chili peppers, and it is the substance that feels “hot” in spicy foods. Capsaicin binds to spinal cord vanilloid (TRVP1) receptors, causing an initial burning sensation. More prolonged administration, usually via a topical cream, usually results in prolonged depolarization of the pain terminals in the spinal cord, temporarily rendering the pathways nonfunctional (defunctionalization). During this phase, the patient experiences resolution of the burning pain, and instead experiences a more numb feeling without the pain. It is a common treatment for postherpetic neuralgia. Bupivacaine binds to voltage gated sodium channels in nerve cells, prevents depolarization, and thus prevents the transmission of a pain response. Fentanyl binds the mu, delta, and/or kappa (as well as other) opioid receptors in the nervous system, with an especially high concentration of them located in the periaqueductal gray region of the brain. Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is effective for the reduction of inflammation and the treatment of modest nociceptive pain. Ziconotide binds to N-type voltage-gated calcium channel blocker in the spinal cord (and brain), and inhibits the release of nociceptive neurotransmitters such as glutamate and substance P, thus decreasing pain levels.
