NMJ OTA

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

A 27-year-old female with a history of cataracts and an unknown family history was referred to the neurology clinic for excessive daytime sleepiness. On examination facial weakness and grip myotonia were appreciated. Genetic testing revealed a mutation in the DMPK gene. Based on her diagnosis, which of the following tests should be performed annually?

A 63-year-old female presents with a 6-month history of difficulty walking and muscle weakness. Neurologic examination reveals normal bulk but muscle fasciculations, bilateral extensor plantar responses, muscle spasticity, and hyperreflexia. Pathology at which of the following structures could explain these symptoms?

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

You are evaluating a 1-year-old who has had delayed motor development and diffuse weakness since birth and presents now to the hospital for a first-time seizure. The physical exam is notable for 3/5 deltoid abduction, 4-/5 hip abduction, 4-/5 hip flexion, and 4-/5 hip extension. He is unable to walk but is meeting cognitive milestones. An MRI brain is done and shows diffuse scattered T2 FLAIR white matter hyperintensities.

If genetic testing is performed, a mutation in which of the following genes would be most expected?

A 57-year-old male with recently diagnosed small cell lung cancer (SCLC) is presenting to the electromyography lab with a one-month history of muscle cramps and muscle pain. Percussive myotonia is appreciated on examination. Electromyography showed myokymic discharges. Autoantibodies against which of the following channels are likely present in this case?

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?

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 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?

A 63-year-old woman with right leg weakness and pain has an MRI performed to evaluate for a possible cause. Her imaging is provided below. Based on the location of the lesion, which of the following muscles is most likely weak on examination?

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 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?

Eteplirsen is an effective treatment in patients with Duchenne muscular dystrophy (DMD) that have which of the following dystrophin mutations?

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 40-year-old male presents to the clinic with difficulty swallowing. On additional questioning, he reports difficulty walking, falls, and dysarthria. Examination shows bilateral facial weakness, fasciculations, and gynecomastia. A CAG trinucleotide repeat on which of the following genes is the cause of this disease?

A 47-year-old female presents to the clinic with the chief complaint of slowly progressive proximal muscle weakness. Electromyography showed short duration, low amplitude motor unit action potentials. A muscle biopsy was performed and shown below. A diagnosis is made and the patient is started on a therapeutic agent. What is the most likely medication initiated?

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

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?

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?

A 65-year-old male presents with an acute onset of back pain, bilateral lower extremity weakness, and bladder incontinence. A physical exam reveals decreased strength and loss of pain and temperature sensation in both legs. Vibratory and light touch sensation and proprioception remain intact. A lesion to which of the following arteries would most likely be responsible for this clinical presentation?

Which of the following is seen on muscle biopsy in patients with steroid myopathy?

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

A 35-year-old male with a past medical history of intravenous drug use presents with back pain, fever, anorexia, and generalized weakness. An MRI of his sagittal spine is shown below. Which of the following is the most likely diagnosis?

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?

Match the phase of the Valsalva maneuver with its associated physiology.

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?

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

A 78-year-old patient with a history of multiple system atrophy (MSA) presents to your clinic for falls. The patient states that while standing he initially experiences feelings of lightheadedness and tunnel vision before a loss of consciousness. While on the ground he will be “twitching” for 30 seconds before he regains consciousness. Which of the following tests is the most likely to be diagnostic in this case?

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 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?

Identify the lesion shown below.

A 57-year-old male with recently diagnosed small cell lung cancer (SCLC) is presenting to the electromyography lab with a one-month history of muscle cramps and muscle pain. Percussive myotonia is appreciated on examination. Electromyography showed myokymic discharges. Autoantibodies against which of the following channels are likely present in this case?

A 65-year-old man presents to the emergency room with progressive weakness over the course of several months. Examination shows pure motor weakness with no sensory involvement, decreased reflexes, and diffuse fasciculations. An EMG shows a conduction block of motor neurons outside of compression sites and normal sensory conduction velocities. Which of the following of most appropriate for treatment?

This muscle biopsy is most consistent with which myopathic disease? 

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 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?

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?

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

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 20-year-old male presents with severe burns on his hands after accidentally touching a stove. Neurology was consulted because the family noted that the patient did not initially pull away from the hot stove as one would expect. Physical exam shows decreased sensation of pain and temperature along the back and arms, with intact strength. T2 sagittal MRI of the cervical spine is shown below. Which of the following is commonly associated with the pathology shown?

A 5-year-old male presents because of muscle stiffness. His symptoms are worse during the colder winter months and with gym class at school. He sometimes becomes so stiff he can hardly breathe. Examination shows no muscle atrophy or hypertrophy but myotonia is present. Upon further questioning, you learn he has an older brother with similar symptoms. What is the likely dysfunctional gene in this patient?

The paraspinal muscles are innervated by which of the following?

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?

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 the relay center for sensory information of the body?

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 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?

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

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

A 42-year-old man with a 6-month history of progressive muscle weakness has a nerve biopsy performed. Based on the toluidine blue (left) and trichrome (right) stain slides shown, which of the following is the most likely diagnosis?

Congenital muscular dystrophies are most often associated with which of the following pathophysiologies?

Which of the following medications, when taken alongside statin therapy, increases the risk of statin-induced myopathy?

A 62-year-old woman with low back pain presents to the emergency department complaining of 4 weeks of a strange sensation when wiping with toilet paper, as well as urinary and fecal incontinence. On exam, she has 5/5 strength throughout her limbs and normal deep tendon reflexes. What is the location of her lesion?

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?

This muscle biopsy is most consistent with which myopathic disease?

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?

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 is correct regarding the H-reflex?

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

A 37-year-old female with a past medical history of chronic fatigue and heat intolerance presents with right arm weakness. A cervical spine MRI is performed and shown below (Left: T2 sagittal. Right: T2 axial). Which of the following is the most likely diagnosis?

A 25-year-old female with no significant past medical history presents with a two-day history of progressive bilateral lower extremity weakness and numbness. On physical exam, she has 3/5 strength in hip flexion and knee extension bilaterally, along with a loss of sensation. She is up to date on all vaccinations. She is afebrile. Sagittal (left) and axial (right) T2 thoracic MRI images are shown below. Which of the following is the most likely diagnosis?

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

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

A 75-year-old man with hypertension and diabetes presents to the emergency department with a sudden onset of loss of sensation in the buttocks, perineum, and inner surfaces of both thighs, and urinary and fecal incontinence. On physical exam, he has loss of pain and light touch in the area described, as well as a loss of sphincter tone, and hyperreflexia in the lower extremities. Strength is mildly decreased in the distal lower extremities, without atrophy. What structure is most likely injured?

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?

Identify the tract marked by the red arrow in the spinal cord diagram below.

What is the mechanism of action of pregabalin?

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 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?

Anti-GQ1b antibodies are associated with which syndrome?

A 45-year-old man with a past medical history of cardiac arrhythmia requiring pacemaker placement is referred to the clinic with a twenty-five-year history of slowly-progressive bilateral ptosis and diplopia. On examination, he has bilateral ptosis, decreased range of motion of the extraocular muscles, and mild proximal weakness in his upper and lower extremities. Which of the following is the most likely diagnosis?

A 45-year-old man with a past medical history of IV drug use presents with a 3-day history of back pain and fever with numbness and tingling in his arms bilaterally. He is now unable to write his name or button his shirt. His cervical MRI is shown below. Which of the following is the most likely diagnosis?

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

A 6-month-old male is admitted to the ED for acute respiratory failure. On examination, he has generalized weakness, diffuse hypotonia, and areflexia. He was admitted to the pediatric Intensive Care Unit and intubated. A chest X-ray showed a narrow chest. EMG/NCS was performed showing axonal motor polyneuropathy with tongue fasciculations and signs of chronic denervation. What is the most likely pathologic etiology causing this presentation?

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

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 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 26-year-old woman presents to the emergency department with third-degree burns covering the entire palmar aspect of her right hand. She claims that she was cooking dinner and touched the stove, but states that she “didn’t notice it was hot”. On neurologic exam, she is unable to distinguish between hot and cold sensations on her hands, arms, shoulders, chest, and back. She also fails to respond to pinprick sensation in the same distribution. She denies any major recent traumatic injuries. Which of the following is the most likely cause of her symptoms?

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?

Initiation of urination involves which of the following physiologic processes?

A 40-year-old previously healthy man arrives in the emergency room with a 1-week history of slowly progressive leg weakness. Symptoms initially started with burning-type pain in his bilateral lower extremities. Neurological examination shows 4-/5 strength in bilateral lower extremities and areflexia of the patella and Achilles. MRI is shown below. Which of the following is the most likely diagnosis?

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

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

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?

A 31-year-old man presents after being found down at the scene of an armed robbery. On physical examination, there is lower extremity weakness and loss of proprioception and vibration on the right side, as well as loss of pain and temperature sensation on the left leg. His MRI is shown below. Which is the most likely condition suffered by this man?

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 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 20-year-old male presents to your clinic for weakness. He is the star baseball player at the local university, but during the season his batting average has been dropping, and he finds he is having trouble standing on his toes, performing overhead shoulder presses, and more recently ascending steps. You give him a script for some blood testing and an EMG/NCS and schedule a follow-up in 2 weeks.

Unfortunately, shortly after returning home he had a fall down a flight of stairs and sustained a compound radius fracture. He was taken to the emergency room where an open reduction and fixation (ORIF) was performed. Shortly after the surgery, he developed tachycardia, tachypnea, and masseter muscle contractions, which then progressed to fever and rigidity.

Which of the following test results is most likely to be seen in this patient?

A 40-year-old male presents with a one-day history of numbness of his right arm. This has never happened before, but he does report an episode of left leg weakness that self-resolved two years ago. The neurological examination confirms a sensory disturbance of his right arm. Sagittal MRI of the cervical spine is shown below (Left: T1, Middle: T1 with contrast, Right: T2). Which of the following is the most likely diagnosis?

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?

This muscle biopsy is most consistent with which myopathic disease?

Which of the following medications is effective in the treatment of myotonia?

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?

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

The F wave response is an:

A 26-year-old male suffered a spinal cord injury after falling from a ladder while hanging Christmas lights. In the ICU, he is experiencing episodes of sudden extreme increases in blood pressure, bradycardia, and diaphoresis. This condition is seen most commonly in lesions of which spinal cord levels?

A 4-month-old boy is brought by his parents due to difficulty in feeding, and episodes of apnea. Physical examination reveals tongue fasciculations, a bulging anterior fontanelle, and an abducens nerve palsy. MRI reveals an Arnold Chiari malformation type II. What additional defect is this child likely to have?