Quiz 05/31/2022 (2)

A 24-year-old male presents to the clinic with numbness in the hands and feet. He has been experiencing these symptoms since his late teens, but the numbness has gotten progressively worse. Additionally, he has been stumbling and losing his balance more frequently in the past 18 months, and he received a new pair of glasses because he was having trouble with his vision at night. On physical exam, he has decreased sensation to vibration and pinprick in his bilateral lower extremities and palpable, enlarged nerves. Laboratory studies reveal an elevated level of phytanic acid. What is the most likely diagnosis?

A 57-year-old woman with a past medical history of hypothyroidism was referred to the EMG lab with a one-year history of right-hand numbness. Based on the EMG data shown below, what is the most appropriate next step in medical management?

A thin 28-year-old male presents to the clinic with complaints of foot drop. On exam, he has a right foot drop as well as numbness on the lateral aspect of the right lower leg. You suspect compression of a nerve at the fibular head. Malfunction of which of the following nerves causes the foot drop itself?

Which is the following potentials on EMG has an irregular firing pattern?

With of the following CMT types present with an axonal pre-dominant peripheral neuropathy?

Patients with Charcot-Marie Tooth disease that have the CMT1A phenotype will have which of the following genetic mutations?

A patient with Duchenne muscular dystrophy (DMD) most likely has which of the following findings on electromyography (EMG)?

A patient with a history of a right shoulder anterior dislocation comes to the clinic with the chief complaint of right arm numbness. On examination, there is a loss of sensation to light touch on the lateral portion of the upper arm. Based on the sensory disturbance, which of the following nerves is most likely injured?

A 30-year-old woman has visual evoked potentials performed that show a right eye P100 latency of 140 msec and a left eye P100 latency of 103 msec. Which of the following is the most likely cause?

Which of the following nerves when damaged can lead to scapular winging?

A 49-year-old male with a chronic history of myalgias was referred to the EMG lab with progressive muscle weakness. Based on the EMG table shown below what is the most likely diagnosis?

A 55-year-old male with a recent history of losing 50 pounds after gastric bypass is referred to the EMG lab with difficulty walking. He has noticed that his left foot drags occasionally causing him to trip and that he has numbness on the top of his left foot up to the middle of his shin. Which of the following statements is the most accurate based on the EMG findings shown below?

Which of the following dermatomes lies closest to the T2 dermatome, relative to the topographical position on the skin?

A 38-year-old male with a history of sarcoidosis and a one-week history of subacute onset of progressive weakness was admitted to the hospital with difficulty ambulating. On examination, you appreciate bilateral lower extremity weakness and hyporeflexia. Based on the clinical history and EMG findings shown below what is the most likely diagnosis?

Which of the following muscles is solely innervated by the C5 nerve root?

A 66-year-old female comes to the EMG lab with the chief complaint of muscle cramps in the right lower extremity. She started having symptoms after treatment with a cholesterol-lowering medication but despite discontinuing the medication her symptoms persisted. Reflexes are 2+ in upper and lower extremities, except 1+ in the right Achilles. Nerve conduction studies of both lower extremities were normal. An EMG was performed and shown below. What is the most likely diagnosis?

A 40-year-old male is referred to the clinic for a one-year history of progressive weakness of the upper and lower extremities. Past medical history is impressive for thrombocytopenia, anemia, and hepatosplenomegaly. Neurological examination shows 2/5 strength in the distal lower limbs bilaterally with diminished ankle and patellar reflexes. The sensory exam shows diminished vibratory and pinprick sensation in both legs. He also has a markedly orange discoloration of his tonsils. Genetic testing is performed which reveals a mutation in the ABCA1 gene. Which of the following is the most likely diagnosis?

Which of the following nerve conduction study abnormalities is least likely to be seen during the initial phase of acute inflammatory demyelinating polyneuropathy (AIDP)?

Which of the following statements is correct regarding F-waves?

What is the earliest NCS/EMG abnormality found in AIDP?

A 47-year-old former football player with a history of diabetes and hypertension presents to the EMG lab with left upper extremity weakness and pain. Motor and sensory nerve conduction studies were normal. An EMG was performed and shown below. What is the most likely diagnosis?

A 6-year-old female is seen in the clinic for decreased balance and numbness in her fingers and toes. Her father, who is with her at the clinic visit, states that she was developmentally normal until 2 years of age, at which time she began to have frequent falls. During the past year, she has also developed slurred speech. The neurological exam reveals truncal ataxia, ataxic gait, scanning speech, and decreased sensation to vibration and pinprick in her extremities. The ocular exam reveals irregular capillary dilation of the retina and skin. What is the most likely diagnosis?

A 65-year-old male is referred to the EMG lab with a recent right leg injury and associated weakness. Based on the EMG shown below, where is the most likely site of neuronal injury?

A 35-year-old male with balance issues is referred for an EMG/NCS. Distal sensory loss of the feet, high-arched feet, and diffuse hyporeflexia are appreciated on the exam. His nerve conduction studies are shown below. Based on the available information what is the most likely diagnosis?

A 63-year-old woman with a history of right-sided breast cancer status post-mastectomy, chemotherapy, and radiation presents to your clinic with a 2 months history of right arm pain and paresthesias. Which of the following findings on EMG/NCS would most likely suggest a radiation-induced plexopathy over a recurrent neoplastic plexopathy?

Which of the following dermatomes are correctly matched with their associated anatomical location?

Which of the following is most likely to show temporal dispersion of the action potential?

What is the mechanism of action of pregabalin?

A 35-year-old man developed a right clavicle fracture after an accidental fall from a ladder while hanging Christmas lights. He was treated conservatively with a figure-of-eight bandage and sling. He presents to your clinic 2 weeks after the accident. He states ever since the accident he has had right arm and shoulder pain, as well as numbness extending from his triceps to his middle dorsal aspect of the forearm, wrist, and dorsal aspect of digits 1,2 and 3. On examination, his strength is 5/5 throughout all extremities except 4/5 to abduction of the deltoid, extension of the triceps, and wrist extension.

Which nerve or cord, if injured by the clavicle fracture, would explain his symptoms?

Which of the following is the most likely diagnosis based on the EMG provided below?

Which of the following brainstem auditory evoked potential (BAEP) results is most consistent with brain death?

Which of the following is the genetic mutation commonly seen in patients with hereditary neuropathy with liability to pressure palsy (HNPP)?

Which of the following CSF findings would be expected in a patient with AIDP?

A 30-year-old female with a history of Charcot-Marie Tooth disease, diagnosed with genetic testing that showed a duplication of the peripheral myelin protein (PMP22) gene, returns to the clinic for a routine follow-up. She expresses interest in starting a family and wants to know what is the risk of her children having the same issues. Which of the following is the most appropriate response?

A 57-year-old navy veteran with a history of PTSD presents with a 2-year history of progressive, asymmetric weakness. The patient states that symptoms started in his left arm. Six months later he started to have falls due to tripping over his right foot. His neurological examination shows weakness of the intrinsic hand muscles of the left arm, ⅖ strength on dorsiflexion of the right ankle, and no sensory disturbances. Reflexes were mute in the left upper extremity and there were several beats of clonus at the right ankle. Fasciculations were present in the tongue, right gastrocnemius, and left tibialis anterior. An EMG is recommended for diagnosis. Which of the following EMG findings are most likely seen in this patient?

A 56-year-old male comes to the clinic with a burning and tingling sensation in his feet and hands for the past 4 months. He has a history of morbid obesity and underwent gastric bypass surgery last year. On physical exam, he has 3+ ankle and patellar reflexes. He also has a positive Babinski and positive Romberg sign. There is impaired position and vibration sense in his big toe bilaterally. This patient’s condition is most likely due to a deficiency of which of the following?

A 42-year-old woman presents to the clinic with a 2-month history of distal symmetric hand weakness that started after hospitalization for severe abdominal pain. Before this hospitalization, she was drinking alcohol with her friends when she acutely developed severe abdominal pain, nausea, restlessness, altered mental status, and hallucinations. She was noted to have dark urine at the time of admission. Since then, her GI symptoms and mentation have returned to baseline, but her weakness has persisted. On exam, she has 3/5 strength of the intrinsic muscles of the hand bilaterally. Conduction velocities of the bilateral upper extremities were unremarkable. Needle EMG revealed fibrillations and decreased recruitment of motor unit action potentials in muscles innervated by the radial and ulnar nerves. Which of the following is the most likely cause of the patient’s symptoms?

A 78-year-old male with a past medical history of diabetes presents to the clinic with a 2-year history of progressive lower extremity numbness and pain. He describes the pain as “pins and needles”. Physical examination reveals loss of pinprick sensation to the ankles bilaterally, mute Achilles reflexes, and moderate difficulty with tandem gait. A diagnosis is made based on examination and clinical history. What is the mechanism of action of the most appropriate first-line therapeutic agent?

A 65-year-old female presents with a complaint of burning and tingling of her feet. Symptoms started in her toes two years ago and now extend up to her ankles. Neurological examination showed normal strength and intact sensation to light touch and vibration but an impaired sensation to pinprick in the first toes bilaterally. If performed, which of the following studies would likely be abnormal?

You are asked to evaluate a patient in the neurointensive care unit who is comatose and has had a somatosensory evoked potential performed. Which of the following is most suggestive of a poor prognosis for this patient?

A 27-year-old previously healthy female is seen at the clinic for 5 days of leg weakness. The weakness has progressively been getting worse and now she has difficulty rising from a chair. Her past medical history is unremarkable except for a few days of an upset stomach and diarrhea that occurred two weeks ago. On physical exam, strength is diminished in the bilateral lower extremities. Deep tendon reflexes are 1+ in the lower extremities. A lumbar puncture is ordered. Testing of the cerebral spinal fluid (CSF) in this patient is most likely to show which of the following?

A 19-year-old male was admitted to the hospital with a 2 weeks history of progressive lower extremity weakness. CSF studies showed an elevated CSF protein and normal WBC count. MRI of the lumbar spine showed contrast enhancement of the cauda equina. His nerve conduction study (NCS) is shown below. What is the most appropriate next step in medical management?

A 19-year-old male with a history of a motorcycle accident 6 weeks ago with several bone fractures of the arms and legs was referred to the EMG lab with right arm numbness since the accident. Where is the most likely site of this patient’s neuronal injury?

A 37-year-old female with a PMH of Sjogren’s, and a recent motor vehicle accident (MVA) is referred to the EMG Lab for evaluation of right arm pain/weakness. The patient endorses right head pain which radiates down her neck into the right shoulder and wrist. Examination shows 5/5 strength in the upper extremities except for 4+/5 deltoid and 4+/5 biceps strength in the right upper extremity. Sensation to light touch was intact throughout. Sensory nerve conduction studies of the right upper extremity were normal. Based on the patient’s EMG results outlined below what is the most likely diagnosis?

A 6-month-old full-term female is referred to the clinic with persistent right shoulder and elbow weakness since birth. Which of the following is the most likely pathologic lesion?

A 52-year-old woman is brought to the emergency room in respiratory distress. She is accompanied by her husband who stated that they were eating at a high-end sushi restaurant when his wife started to complain of perioral numbness and tingling. Two hours later she started to complain of generalized weakness and trouble breathing. Accidental poisoning is suspected. Based on the available information, what is the mechanism of action of the poison ingested?

A 62-year-old man comes to the clinic complaining of a 2-month history of difficulties getting up from a chair, climbing steps at work, and lifting objects above his head. His primary care physician also noticed a rash on sun-exposed areas of the man’s body. EMG of proximal muscles on this patient with likely reveal which is the following?

A 71-year-old male with a history of mild ankle weakness and balance issues for the last 6 years is referred to the lab for a nerve conduction study (NCS). While performing the testing the patient states that a few of his siblings, as well as his father, had similar issues. Examination showed high arches and hammertoes. Based on the clinical history and NCS, what is the most likely diagnosis?

A 56-year-old female presents to the clinic with right posterior leg pain. On examination, there is decreased sensation of the right posterior calf and weakness in right ankle plantarflexion. EMG testing shows fibrillations of the gastrocnemius and gluteus maximus muscles. EMG testing of the tibialis anterior, gluteus medius, and tensor fascia lata were normal. What is the most likely etiology of this patient’s symptoms?

A 49-year-old female has had a 6-month history of difficulty swallowing and weight loss. On examination, she has generalized muscle loss. On strength examination, she has 3/5 proximally and 4/5 distally in the bilateral upper extremities. There are normal tongue movements and a normal jaw jerk reflex. Deep tendon reflexes in the bilateral upper extremities are normal and sensation is intact. An EMG is performed and outlined below. What is the most likely diagnosis?

A 55-year-old male presents to the clinic with a complaint of right lower extremity pain and weakness. On examination of the right lower extremity, there is decreased sensation to pinprick on the medial calf and foot, 4/5 strength with knee extension, and a mute patellar reflex. These findings are most likely due to radiculopathy of which of the following nerve roots?

Which of the following features on EMG is suggestive of chronic denervation?

A 33-year-old female presents to the clinic for evaluation of a left lower extremity foot drop. On physical examination, there is weakness in dorsiflexion. Ankle eversion, inversion, and plantar flexion strength are normal. Hip abduction strength is normal as well. Which of the following is the most likely etiology for the patient’s symptoms?

EMG abnormalities in which of the following muscles can not localize to the brachial plexus?

An EMG/NCS is performed for the evaluation of subacute left upper extremity weakness in an adult female. There are fibrillation potentials in the deltoid and biceps on EMG and decreased median and radial sensory amplitudes on NCS. Which portion of the brachial plexus was injured?

A 67-year-old male wakes up with a painful, right-sided, itchy rash coming across his abdomen like a band involving the umbilicus. His primary care provider is concerned that the patient has shingles. For this patient, re-activation of the varicella-zoster virus occurred at the dorsal root ganglion at which thoracic level?

A 66-year-old right-handed male presents to the EMG/NCS lab with right upper extremity pain, numbness, and weakness. Based on the data collected, what is the most likely diagnosis?

A 37-year-old male with the chief complaint of insidious unilateral hearing loss was found to have an acoustic neuroma on MRI. If a brainstem auditory evoked potential (BAEP) was performed which of the following would be most likely found?

A 20-year-old female presents to the clinic with weakness and numbness in the right leg. She states that earlier in the day she was taking a long nap on her right side, and when she awoke, her entire leg felt like pins and needles. When she got up, she felt that she was dragging her right leg on the floor. She has had similar experiences in other limbs over the years but symptoms would slowly improve over weeks. Nerve conduction studies showed a right common peroneal nerve conduction block and mildly decreased conduction velocities of all nerves tested. Her mother reports that her father had similar episodes before he passed away from an unrelated illness. Which of the following is the most likely diagnosis?

Which of the following nerves is a terminal branch of the posterior cord?

Which of the following is classically seen on electromyography in a patient with a chronic neuronal injury?

The patient is a 79-year-old male with a past medical history of myocardial infarction who was referred for a nerve conduction study (NCS) to evaluate his slowly progressive lower extremity numbness and weakness. Which of the following pathologies is most commonly associated with the findings shown in the (NCS) shown below?

You are reading a visual evoked potential (VEP) that has a prolonged P100 latency in the right eye and a normal latency in the left eye. Of the following, which pathology is most consistent with this study?

Damage to which of the following muscles can lead to scapular winging?

A 50-year-old male has noted winging of his right scapular and pain for the past four months following a hyperextension injury. Based on the EMG data outlined below where is this patient’s pathological lesion?

The F wave response is an:

Mild cases of carpal tunnel syndrome will have which of the following findings on electromyography (EMG)?

A 24-year-old with a history of a motor vehicle accident and a broken leg is referred to the EMG lab with a left leg foot drop. Based on the EMG table outlined below, where is the most likely site of neuronal injury?

The pathologic findings on the image shown below can be secondary to bilateral mononeuropathies involving which of the following nerves?

A 21-year-old female was admitted to the hospital with a 3 weeks history of progressive lower extremity weakness. An EMG was performed and the results were shown below. Based on the clinical history, examination, and diagnostic testing, the patient was started on plasma exchange (PLEX) therapy. After completing her PLEX therapy there was a marked improvement in her weakness. Although not shown below, which of the following additional NCS/EMG results were also likely present on the day of recording?

Which of the following is correct regarding the H-reflex?

A 45-year-old male presents with left-sided neck and shoulder pain. On examination, there is right arm abduction weakness and decreased bicep and brachioradialis reflexes. An EMG was ordered and showed fibrillations of the deltoids, supraspinatus, and biceps muscles. EMG testing of the triceps, first dorsal interosseous, abductor policies brevis, and rhomboid muscles were normal. These findings are most likely due to radiculopathy of which of the following nerve roots?

Anti-GQ1b antibodies are associated with which syndrome?

A 30-year-old male presents to the clinic with a fifteen-year history of progressive weakness and sensory loss in his lower extremities. Examination shows hammertoes, high arches on his feet, 4/5 ankle dorsiflexion strength, and a mild decrease in sensation to pinprick in the 1st toes bilaterally. Upon questioning he mentions that his father had similar-looking feet and started to use a cane in his fifties. What is the most likely diagnosis for his symptoms?

A 27-year-old presents to the clinic with finger extension, wrist extension, shoulder abduction, and shoulder adduction weakness. There is also numbness along the lateral and posterior arm. Which of the following is the most likely cause of the patient’s symptoms?

A 45-year-old female who is a professional pianist was referred to the EMG lab for right-hand numbness and tingling. Based on the EMG data outlined below where is this patient’s pathological lesion?

Concentrically-layered Schwann-cell processes (“onion bulbs”) are seen surrounding nerve fibers on nerve biopsy in which of the following diseases?

A 48-year-old male with a history of a motor vehicle accident and right leg tibial plateau fracture was referred to a neurologist because of right leg weakness. He states he often catches his right foot while walking and stubs his toes when he walks barefoot. On examination, there is decreased ankle dorsiflexion and eversion of the foot. Weakness of which of the following muscles is responsible for the patient’s symptoms?

Charcot Marie Tooth disease (CMT) is associated with which of the following pathologic findings?

Cool limbs during a nerve conduction study will have which of the following effects on the data recorded?

Which is the following findings on EMG is suggestive of a chronic neurogenic lesion?

Submaximal muscle stimulation is used during which of the following aspects of the nerve conduction study?

Which of the following forms of Charcot-Marie-Tooth (CMT) disease causes axonal polyneuropathy?

Fibrillations and positive waves are first seen on electromyography (EMG) at which point following a nerve transection?

Which of the following is classically seen on electromyography in a patient with an acute neuronal injury?

A 57-year-old male undergoes a cervical decompression laminoplasty for myelopathy, and on postoperative day #2, he complains of severe left shoulder pain. On examination, he has weakness with abduction of the left arm at the shoulder and flexion of the left arm at the elbow. This patient’s lesion localizes to which nerve root?

A 46-year-old female presents to the clinic with right-hand numbness, specifically in the 4th and 5th digits. EMG testing reveals fibrillations on the first dorsal interosseous, and flexor pollicis longus. EMG testing of the abductor pollicis brevis and triceps was unremarkable. These findings are most likely caused by radiculopathy of which of the following nerve roots?

Which of the following is the resting membrane potential of a neuron?

A 57-year-old male with a past medical history of progressive weakness affecting all extremities and dysphagia for the past 6 months is admitted to the hospital. An EMG was completed as part of his workup and is shown below. Based on the available information what is the most likely diagnosis?

Which of the following is the first abnormal EMG/NCS finding seen in a patient with carpal tunnel syndrome?

The paraspinal muscles are innervated by which of the following?

What is the typical brainstem auditory evoked response (BAER) finding with cortical hearing loss?

A patient with right leg weakness presents to the neuromuscular lab for electromyography. The image below depicts a spontaneous finding while evaluating the right tibialis anterior muscle. This finding is most consistent with which of the following?

A 37-year-old female presents to the emergency room with diplopia and ambulation issues. Other than having an upper respiratory tract infection two weeks ago, there is no other significant past medical history. On physical exam, the patient has a decreased range of motion of the extraocular muscles bilaterally, diffuse areflexia, and marked dysmetria on finger-to-nose and alternating movements testing. Which of the following autoantibodies is most likely associated with this disease?

A 30-year-old male presents to the clinic with a fifteen-year history of progressive weakness and sensory loss in his lower extremities. Examination shows hammertoes, high arches on his feet, 4/5 ankle dorsiflexion strength, and a mild decrease in sensation to pinprick in the 1st toes bilaterally. Upon questioning he mentions that his father had similar-looking feet and started to use a cane in his fifties. Which of the following genetic mutations may be the cause of the patient’s symptoms?

A 60-year-old woman with a history of diabetes is presenting to the neurology clinic with a 4-month history of burning/tingling in her bilateral toes. Neurological examination revealed 5/5 strength in all muscle groups, normal reflexes, and intact sensation to light touch in the bilateral lower extremities. There was mildly decreased sensation to pinprick in the 1^st toe bilaterally. Which of the following tests is the most likely to be diagnostic for this patient?

A neurology consult was placed for a 35-year-old male who was admitted overnight after a motor vehicle accident that occurred earlier in the day. He experienced multiple bone fractures, including the right humerus at the spiral groove. The primary team is concerned about a radial nerve injury. Which of the following findings are most likely to be found on EMG/NCS?

A 16-year-old male with no significant past medical history presents to the emergency room with vision complaints and coordination issues. Four days ago, he began experiencing double vision and since then has had progressive difficulty picking up objects and buttoning his shirts. On physical exam, the patient has a decreased range of motion of the extraocular muscles bilaterally, as well as areflexia and ataxia when walking. What is the most likely diagnosis?