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Zoe MCQ 14
Listed are the principal eye muscles and the movements they contribute to. Select the answer choices that are correct.
 
Zoe MCQ 12
While running the Boston Marathon (just for fun), what type of muscle are you using
 
Dillon MCQ 33
You ask a patient to touch their nose, but they cannot despite completely intact muscle strength and normal range of movement. This is an example of what
 
Dillon MCQ 21
The principle muscle involved in extortion of the eyes is _______.
 
Dillon MCQ 03
Botulism toxin can be used in the treatment of muscle spasms and headaches, the best description of the MOA is which of the following
 
Muscle Fiber Action Potential

 
Peripheral Nervous System and Neurologic Exam - Question 6
Absent reflexes are most characteristic of:
 
Peripheral Nervous System and Neurologic Exam - Question 5
Which of the following is most likely to be helpful in diagnosing a lesion within the peripheral nervous system
 
Peripheral Nervous System and Neurologic Exam - Question 4
A patient presents with weakness. Which of the following physical exam findings is suggestive of a lesion within the peripheral nervous system
 
Peripheral Nervous System and Neurologic Exam - Question 3
What is a myopathy
 
Peripheral Nervous System and Neurologic Exam - Question 2
Which of the following is not a disease process within the peripheral nervous system
 
Peripheral Nervous System and Neurologic Exam - Question 1
Which of the following is not considered part of the peripheral nervous system
 
Electromyography and Neuromuscular Disorders - Chapter 2 Quiz - Question 1
Which of the following is not considered part of the peripheral nervous system
 
EMG Findings 01
In the needle EMG study shown in the video above, the finding of motor unit action potentials that are large, long, and polyphasic would be most consistent with which of the following
 
Physiology Terms 01
Delayed relaxation of skeletal muscle after voluntary contraction, related to hyperexcitability of the muscle membrane is called:
 
Median motor nerve conduction study normal values 01
You are performing a motor nerve conduction test on an adult. You are testing the median nerve, recording at the abductor pollicis brevis muscle. Of the following choices, which best defines the normal amplitude value
 
Neuromuscular 10
Courtesy of Dr. Mark Cohen What does this biopsy specimen show
 
Neuromuscular 04
Courtesy of Dr. Mark Cohen These strongly NADH-TR positive structures may be seen in which of the following conditions
 
Neuromuscular 05
Courtesy of Dr. Mark Cohen The histopathologic features seen within this trichrome stained muscle biopsy may be seen in all of the following conditions, EXCEPT:
 
Neuromuscular 09
Courtesy of Dr. Mark Cohen Diseases characterized by these ultrastructural features on muscle biopsy may show all of the following, EXCEPT:
 
Neuromuscular 07
Courtesy of Dr. Mark Cohen This 4 year old boy with polymicrogyria showed mutation in which of the following proteins
 
Neuromuscular 06
Courtesy of Dr. Mark Cohen This NADH-TR stained muscle shows features most consistent with:
 
Malformations 01
Courtesy of Dr. Mark Cohen Which of the following gene mutations is most closely associated with this neuronal migration disorder
 
Neuromuscular 03
Courtesy of Dr. Mark Cohen This 42-year old former all-American quarterback comes in complaining of slowly progressive lower extremity weakness which began just after he got married 15 years ago. Which of the following diagnoses is most likely correct
 
Upper extremity muscle function and innervation 04
During a needle EMG of the upper extremity, you notice a large number of fibrillations in the pronator teres muscle while the patient is at rest. From this, you deduce that the patient has a lesion. Of the following options, which lesion is most compatible with the EMG findings
 
Upper extremity muscle function and innervation 04
During a needle EMG of the upper extremity, you notice a large number of fibrillations in the pronator teres muscle while the patient is at rest. From this, you deduce that the patient has a lesion. Of the following options, which lesion is most compatible with the EMG findings
 
Type I Muscle Fibers
Which of the following statements about type I muscle fibers is most accurate
 
A Silence!
You are doing an EMG for a 7-year-old male with progressive proximal weakness and waddling gait and greatly raised serum CPK. The EMG needle is inserted into the left calf, but no insertional activity is being recorded; what is the likely explanation of this observation
 
I'm Weak, but Why?
A 32-year-old woman presents with painless fatigable weakness and bilateral partial ptoses. Her deep tendon reflexes are intact, as is her sensory system. She a refugee from Somalia and her English is very poor in spite of being in the States for the past 4 years...
 
A Flaccid Body!
A 21-year-old college student is brought to the ER short of breath 2 days after having difficulty walking which started 4 days ago. The patient is dyspneic but fully conscious.Examination reveals flaccid areflexic quadriparesis of grade 2, proximal and distal, with normal sensation...
 
Special Muscle Receptors 01
A 79 year-old houseplant canner presents to your clinic for evaluation of anxiety. During your exam, you bang on his knee with a hammer. Which of the following statements most accurately describes the afferent limb of the reflex arc you are trying to elicit
 
Cholinergic and Anticholinergic agents 01
Because someone told him to do it, a 32 year-old fisherman ingested insanely huge quantities of scopolomine. Which of the following findings will he not have as a result of taking this drug
 
Dysphagia as a presenting symptom 01
An adolescent presents with complaints of dysphagia and dysarthria. The patient's father uncle reportedly has a history of muscle weakness that began similarly. On exam, there is wasting of the tongue, with fasciculations. The remainder of the exam is normal...
 
Lower extremity muscle function and innervation 07
Which of the following nerves is involved in bringing innervation to the peroneus brevis
 
Lower extremity muscle function and innervation 08
Which of the following muscles is innervated by peroneal fibers in the sciatic nerve
 
Lower extremity muscle function and innervation 06
The anterior divisions of the anterior rami of the L2-L3-L4 roots join to form which of the following nerves
 
Lower extremity muscle function and innervation 05
The posterior divisions of the anterior rami of the L2-L3-L4 roots join to form which of the following nerves
 
Roots of the brachial plexus and the muscles they innervate 01
Which of the following roots provide innervation to the flexor digitorum profundus to digit 2
 
Nerves arising from the brachial plexus and the muscles they innervate 01
The deltoid is innervated by which of the following nerves
 
Cords of the brachial plexus and the muscles they innervate 01
The extensor carpi ulnaris muscle is innervated by which of the following cords of the brachial plexus
 
Trunks of the brachial plexus and the muscles they innervate 01
The extensor pollicis longus muscle is innervated by which of the following trunks of the brachial plexus
 
Upper extremity muscle function and innervation 03
During a needle EMG of the upper extremity, you notice a large number of fibrillations in the first dorsal interosseous muscle while the patient is at rest. From this, you deduce that the patient has a lesion. Of the following options, which lesion is most compatible with the EMG findings
 
Upper extremity muscle function and innervation 03
During a needle EMG of the upper extremity, you notice a large number of fibrillations in the first dorsal interosseous muscle while the patient is at rest. From this, you deduce that the patient has a lesion. Of the following options, which lesion is most compatible with the EMG findings
 
Upper extremity muscle function and innervation 02
During a needle EMG, you notice a large number of fibrillations in the abductor pollicis brevis muscle while the patient is at rest. From this, you deduce that the patient has a lesion. Of the following options, which lesion is most compatible with the EMG findings
 
Upper extremity muscle function and innervation 02
During a needle EMG, you notice a large number of fibrillations in the abductor pollicis brevis muscle while the patient is at rest. From this, you deduce that the patient has a lesion. Of the following options, which lesion is most compatible with the EMG findings
 
Upper extremity muscle function and innervation 01
Of the following choices, which muscle receives the most proximal innervation from the median nerve
 
Upper extremity muscle function and innervation 01
Of the following choices, which muscle receives the most proximal innervation from the median nerve
 
paroxysmal spells 01
A 28 man in otherwise good health is standing, speaking with his girlfriend. In response to a humorous statement, he begins laughing hysterically. Suddenly, he collapses to the ground. He remains awake and alert, but is very weak for several seconds. The most accurate term for this phenomenon is:
 
Chiari Malformations 03
An adult patient presents to your clinic. Because of symptoms he describes, you obtain the MRI shown above. Which of the following symptoms were most likely among this patient's complaints
 
Hereditary Motor and Sensory Neuropathies 02
You examine a child with diminished ankle reflexes, pes cavus, scoliosis, wasting of the calf muscles, and weakness. On nerve conduction study, you find severe slowing of the conduction velocity. Several of the patient's relatives have had similar symptoms,...
 
Cranial Nerves 01
Which of the following nerves emerges as a branch off of CN VII at the geniculate ganglion
 
Neuromuscular Disorders 01
The Gomori trichrome stained muscle biopsy shown above is most consistent with which of the following disorders
 
Muscle Fiber Histology 02
This photomicrograph shows a cytochrome C oxidase stain of skeletal muscle. In normal muscle, which of the following statements is true about the fibers that stain DARKER with cytochrome C oxidase
 
Muscle Fiber Histology 01
This photomicrograph shows a cytochrome C oxidase stain of skeletal muscle. In this type of stain:
 
Myopathies 04
The image above shows an electron micrograph of a skeletal muscle biopsy. Which of the following statements about this condition is most accurate
 
Guess the disease!
GUESS WHAT I'M THINKING! I'm thinking of a variant of multiple sclerosis (MS), in which optic neuritis and transverse myelitis occur together, or at least within weeks of each other. The transverse myelitis frequently leads to necrosis, and is thus...
 
Floppy Infant 01
A term infant is notably weak and hypotonic at birth.  The child is a product of an unremarkable pregnancy and a normal vaginal delivery with no other complications.  The mother, a 32-year old female, had regular prenatal visits.  Her past medical history...
 
Comprehensive Neurological Workup
A 28-year old right-handed man with no prior medical history visits the opthalmologist for followup after refractive surgery for unilateral astigmatism the previous month. A normal left fundus is visualized, but an incidental finding is made of a small foul-smelling...
 
Inclusion Body Myositis 01
A 66 year-old right handed male presents with a 3-year history of worsening weakness. He complains of difficulty walking up stairs. Past medical history and family history are unremarkable. Exam is normal except for symmetric weakness in the quadriceps and finger flexors...
 
EEG Patterns 02
A 65 year-old right-handed male had an episode of sudden loss of consciousness about 1 month ago. He is now having an EEG as part of his workup. The sharply contoured waves circled in red represent:
 
EEG patterns 01
This EEG shows someone who is:
 
Movement disorders and sleep
Which of the following movement disorders is present (persists) during sleep
 
Motor nerve conduction study normal values
You are performing a motor nerve conduction test on an adult. You are testing the tibial nerve, recording at the abductor hallucis brevis muscle. What is the normal value for the amplitude
 
spinal segments innervating muscles of the lower extremity
Which of the following is most accurate regarding spinal segments innervating muscles of the lower extremity
 
Lower extremity muscle function and innervation 4
Which motion would be most affected by a lesion of the superficial peroneal nerve
 
Innervation of muscles of the upper extremity
Which of the following muscles is innervated by the median nerve
 
Lower extremity muscle function and innervation 3
Which muscle or muscles would be most affected by a lesion of the obturator nerve
 
Lower extremity muscle function and innervation 2
Which muscle or muscles would be most affected by a lesion of the S1 and S2 spinal roots
 
Lower extremity muscle function and innervation 1
Which movement would be most affected by a lesion of the L2 and L3 spinal roots
 
nerves innervating the muscles of the upper extremity
Which of the following statements regarding nerves innervating the muscles of the upper extremity is FALSE
 
Muscles innervated by the ulnar nerve
Which of the following muscles is innervated by the ulnar nerve
 
Muscles innervated by the radial nerve
Which of the following muscles is innervated by the radial nerve
 
Spinal segments innervating muscles of the lower extremity 1
Which of the following spinal segments typically contributes to the innervation of the quadratus femoris muscle in the lower extremity
 
Muscles innervated by the median nerve
Which of the following muscles is innervated by the median nerve
 
Extraocular muscles
A 72 year-old female zookeeper visits you in the Albuquerque Baloon Fiesta, complaining of diplopia. You note that most of the time that she is facing you and talking, she sits with her chin turned toward her right shoulder and her left eye adducted. Based...
 
Motor tracts 1
Which of the following is a major function subserved by the Lateral Corticobulbar Tract
 
Spinal segments innervating muscles of the lower extremity 2
Regarding the muscles of the lower extremity, which of the following muscles typically receives innervation from the S2 spinal segment
 
Peripheral nerves innervating muscles of the lower extremity
Of the following choices, which ONE answer most accurately describes the nerve or nerves which most typically innervate Abductor hallucis
 
Hereditary Motor and Sensory Neuropathies 01
You examine a child with pes cavus, diminished ankle reflexes, scoliosis, and weakness with wasting of the calf muscles. On nerve conduction study, you find severe slowing of the conduction velocity. Of the following, which of the following syndromes is the most appropriate diagnosis
 
Lower Extremity EMG 01
A patient presents with lower extremity weakness. Needle EMG study of the gastrocnemius and gluteus maximus reveals large, long, polyphasic motor unit action potentials. Needle EMG study of the vastus medialis, vastus lateralis, extensor digitorum longus and tibialis anterior are normal...
 
Spontaneous Activity on Needle EMG 02
Of the following, which pattern of spontaneous activity on EMG represents the firing of motor units (as opposed to muscle fibers)
 
Spontaneous Activity on Needle EMG 02
Of the following, which pattern of spontaneous activity on EMG represents the firing of muscle fibers (as opposed to motor units)
 
Spontaneous Activity on Needle EMG 01
You are performing a needle EMG study. You notice spontaneous discharges. They are single discharges, stable in amplitude, firing at a rate of about 10 Hz with a regular rhythm. Of the following choices, what are these discharges most likely to be
 
Nerve Injuries Affecting the Upper Extremity
A Greek female deity was gouged in the axilla by a Narwhal yesterday. She presents to your clinic today complaining of numbness in the area shaded in green in the image above. She also, as pictured, is unable to extend her arm at the elbow, or abduct at the shoulder...
 
Nerve Injuries Affecting the Upper Extremity
A Greek female deity was gouged in the axilla by a Narwhal yesterday. She presents to your clinic today complaining of numbness in the area shaded in green in the image above. She also, as pictured, is unable to extend her arm at the elbow. Abduction at the shoulder has been spared...
 
Nerve Injuries Affecting the Upper Extremity
A Greek female deity was gouged in the axilla by a Narwhal 6 weeks ago. She presents to your clinic today complaining of numbness in the area shaded in green in the image above. She also, as pictured, is unable to extend her arm at the elbow. Abduction at the shoulder has been spared...
 
Nerve Injuries Affecting the Upper Extremity
A Greek female deity was gouged in the axilla by a Narwhal yesterday. She presents to your clinic today complaining of numbness in the area shaded in green in the image above. She also, as pictured, is unable to extend her arm at the elbow. Abduction at the shoulder has been spared...
 
Fish MCQ 14
Which of the following is TRUE about type I muscle fibers Select all that apply
 



User Forums and Comments



Re: Re: Comment
Actually, all the choices represent some form of spontaneous activity.  The question is about the generator of said activity.  Fasciculations, doublets, triplets, multiplets, myokymia, cramp potentials, neuromyotonic potentials, and the potentials of a resting...
 
Re: Comment
I think Dr. Miles is simply noting that all the other choices are due to increased insertional activity. I assume the question is kind of a which one of these things is not like the other. All the distractor answers describe classic insertional activity pattern...
 
Cholinesterase inhibitor poisoning
DUMBBELSSDiarrheaUrinationMiosisBronchospasmBradycardiaExcitation of skeletal muscle and CNSLacrimationSweatingSalivationAntidote: Atropine
 
Muscle innervated by Radial Nerve
RAW (as in Radial) BEAST RAW: Radial (picture a beast yelling RAW) Brachialradialis Extensors ABDuctor pollicis longus Supinator Tricepts
 



Online Course Content



Cells are Batteries
 Section 1: Cells are BatteriesCells are Batteries.  They generate an electrical potential (voltage) across the cell membrane.  For most cells, this is analogous to the DC current generated by a battery.   The video above shows how the voltage...
 
Synapses and the Neuromuscular Junction (NMJ)
 Section 6:  Synapses and the Neuromuscular Junction (NMJ)Neurons can use electrical potentials to send signals from one part of the neuron to another, but to communicate with other neurons (or muscle cells or other target cells), they usually use chemical signals...
 
Muscle Fiber Action Potential
 Section 5: Muscle Fiber Action PotentialWhen the cell membrane of neurons or muscle fibers is depolarized enough, they propagate a nondecremental wave of electrical polarization called an action potential.  Neurons use these action potentials to quickly transmit information across distance...
 
The Neuron Action Potential
 Section 4: Neuron Action PotentialWhen the cell membrane of neurons or muscle fibers is depolarized enough, they propagate a nondecremental wave of electrical polarization called an action potential.  Neurons use these action potentials to quickly transmit information across distance...
 
Meat Wires
 Section 3:  Meat WiresNerve cells (neurons) and muscle cells (muscle fibers) are specialized cells whose cell membrane potential can change.  These changes contribute to the basic functioning of these cells.  Nerve cell processes can carry electical signals similar to how wires do...
 
Why Are Cells Batteries?
 Section 2:  Why Are Cells BatteriesIn this second section of this chapter, we explore the origin of the cell membrane potential.  We've established that Cells are Batteries. Batteries have an electrical potential.  That's what makes them batteries...
 
NMJ (image)

 
Muscle Fiber Action Potential
489
 
Basic Physiology of Nerve and Muscle
 Basic Physiology of Nerve and MuscleLearning objectives:   To gain an understanding of basic physiology of nerves and muscleTo understand what a membrane potential is and what makes it happenTo understand what an action potential is, and how it comes aboutTo...
 
Neuroanatomy
A set of educational materials intended to supplement a second-year medical school neuroscience course. If you are currently using this to study neuroanatomy, I would request that you direct any questions to me through the Neuroanatomy User Forum on FrontalCortex...
 
Electric Meat
Electric MeatWhy is the nervous system different from skin, liver, kidneys, or spleen  The fundamental building blocks of the nervous system and muscles are electrically active cells.   These cells process inputs and generate outputs.  Neurons are individual...
 
Vision
VisionA introduction to the anatomy and physiology of the eye and structures that are involved in vision.Terminology:By the end of this section, make certain that you understand what each of these terms mean, and can apply them appropriately.  If applicable,...
 
Cerebellum
Cerebellum A description of the anatomy and function of the cerebellum.Terminology:By the end of this section, make certain that you understand what each of these terms mean, and can apply them appropriately.  If applicable, make sure you can find each item...
 
Motor Cranial Nerves
Motor Cranial NervesThis section describes the cranial nerves that carry motor information. Also discusses corticobulbar pathways.Terminology:By the end of this section, make certain that you understand what each of these terms mean, and can apply them appropriately...
 
Motor Pathways
Motor PathwaysThis section describes the anatomical structures that carry motor information from the brain to the body, including upper motor neuron and lower motor neuron pathways.Terminology:By the end of this section, make certain that you understand what...
 
NMJ (image)

 
Abductor Digiti Quinti Pedis (video)

 
Online courses
On FrontalCortex.com, you can create a collection of multimedia resources organized into a coherent structure focused on one topic.This is considered an online course. An example of this is the neuropathology course, or the EMG course. Mixing with Face-to-Face...
 
S1
The muscles that are bolded below are prodiminanty S1 innervated. abductor digiti quinti pedisabductor hallucis brevisbiceps femoris - long headbiceps femoris - short headextensor hallucis longusflexor digitorum longusgastrocnemius - lateral headgastrocnemius...
 
C7
Spinal Root: C7Muscles Innervated:    anconeus *    extensor carpi radialis longus    extensor carpi ulnaris    extensor digitorum ***    extensor indicis **    extensor pollicis longus    extensor pollicis brevis    flexor carpi ulnaris   ...
 
C6
Spinal Root: C6Muscles Innervated:    anconeus **    biceps brachii*    deltoid *    brachioradialis *    deltoid *    extensor carpi radialis longus    flexor carpi radialis **    Infraspinatous *    pronator teres **    triceps...
 
C5
Spinal Root: C5Muscles Innervated:    Supraspinatus *    Infraspinatous *    Rhomboids    biceps brachii *    brachioradialis *    deltoid   *    extensor carpi radialis longus ** Please note, that these muscles along cannot differentiate...
 
C8
Spinal Root: C8Muscles Innervated:    flexor digitorum superficialis    abductor pollicis brevis    opponens pollicis    pronator quadratus    flexor digitorum profundus to digit 2    flexor digitorum profundus to digit 3    flexor pollicis brevis ...
 
Upper Extremity
    abductor digiti minimi    abductor pollicis brevis    anconeus    biceps brachii       brachioradialis    deltoid    extensor carpi radialis longus    extensor carpi ulnaris    extensor digitorum    extensor indicis   ...
 
Radial Motor NCS, Recording the Extenor Digitorum Communis (EDC), stimulating proximal to Spiral Groove (image)

 
Radial Motor NCS, Recording the Extenor Digitorum Communis (EDC), stimulating distal to Spiral Groove (image)

 
Radial Motor Nerve Conduction Study, recording Extensor Indicis Proprius, stimulating Proximal to Spiral Groove (image)

 
Radial Motor Nerve - Recording the Extenor Indicis Proprius (EIP)
Origin:  C7-C8 roots, middle and lower trunk and posterior cord of the brachial plexus, radial nerve.Recording Site:  Extensor Indicis Proprius muscle (EIP)Reference Site:  Dorsal and medial wrist, near the styloid process of the ulnaGround:  Posterior...
 
Radial Motor NCS, Recording the Extenor Indicis Proprius (EIP), stimulating below groove (A) (image)

 
Radial Motor NCS, Recording the Extenor Indicis Proprius (EIP), stimulating below groove (B) (image)

 
Median Motor Nerve Conduction Study, Recording Abductor Pollicis Brevis, Stimulating at the Wrist (image)

 
Median Motor Nerve Conduction Study - Recording Abductor Pollicis Brevis, Stimulating at Axilla (image)

 
Median Motor Nerve Conduction Study - Recording Abductor Pollicis Brevis, Stimulating at Elbow (image)

 
Median Motor Nerve Conduction Study - Recording Abductor Pollicis Brevis, Stimulating at Wrist (image)

 
Musculocutaneous Motor Nerve Conduction Study - recording the Biceps, Stimulating at Erb's point (image)

 
Musculocutaneous Motor Nerve Conduction Study - recording the Biceps, Stimulating at Erb's point (image)

 
Musculocutaneous Motor Nerve Conduction Study - recording the Biceps, Stimulating at Erb's point (image)

 
Musculocutaneous Motor Nerve Conduction Study - recording the Biceps, Stimulating at Axilla (image)

 
Musculocutaneous Motor Nerve Conduction Study - recording the Biceps, Stimulating at Axilla (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating at axilla (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating at axilla (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating at Erb's point (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating at Erb's point (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating at Erb's point (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating at Erb's point (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating proximal to elbow (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating distal to elbow (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating distal to elbow (image)

 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM), stimulating at wrist (image)

 
Radial Motor NCS, Recording the Extenor Digitorum Communis (EDC), stimulating at elbow (image)

 
Radial Motor NCS, Placement of electrodes on EDC (image)

 
Median Motor Study - Recording the Abductor Pollicis Brevis
Origin:  C8-T1 roots, lower trunk and medial cord of the brachial plexus, median nerve.Recording Site:  Abductor Pollicis Brevis muscle (APB)Reference Site:  Base of thumbGround:  Palm or top of handStimulation Sites:  Wrist and elbowProcedure:  The...
 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM)
Origin:  C8-T1 roots, lower trunk and medial cord of the brachial plexus, ulnar nerveRecording Site:  Abductor Digiti Minimi muscle (ADM)Reference Site:  Base of little fingerGround:  Palm or top of handStimulation Sites:  Wrist, below elbow and above elbow...
 
Radial Motor Nerve - Recording the Extenor Digitorum Communis (EDC)
Origin:  C7-C8 roots, middle and lower trunk and posterior cord of the brachial plexus, radial nerve.Recording Site:  Extensor Digitorum Communis muscle (EDC)Reference Site:  Above the wristGround:  Medial forearmStimulation Sites:  Elbow and arm (below...
 
Musculocutaneous Motor Nerve - recording the Biceps
Origin:  C5-6 roots, upper trunk and lateral cord of the brachial plexus, Musculocutaneous nerve.Recording Site:  Biceps muscleReference Site:  Distal upper armGround:  Upper armStimulation Site:  Axilla and Erb’s point.Procedure:  The recording electrode...
 
Axillary Motor Nerve - recording the Deltoid
Origin:  C5-6 roots, upper trunk and posterior cord of the brachial plexus, axillary nerve.Recording Site:  Deltoid muscleReference Site:  Distal upper armGround:  ShoulderStimulation Sites:  Erb’s PointProcedure:  The recording electrode is placed...
 
Spinal Accessory Motor Nerve - recording the Trapezius
Origin:  C2-C4 roots, cervical plexus, spinal accessory nerve.Recording Site:  TrapeziusReference Site:  ShoulderGround:  Upper backStimulation Site:  Posterior neckProcedure:  The recording electrode is placed on the belly of the trapezius muscle. ...
 
Saphenous Sensory Nerve – recording anterior to the Medial Malleolus (antidromic)
Origin:  L3-4 roots, lumbar plexus, femoral nerveRecording Site:  Lower calf at ankle (bar electrode)Reference Site:  Lower calf at ankle (bar electrode)Ground:  Lower legStimulation Site:  CalfProcedure:  The recording and reference electrodes (bar...
 
Peroneal Motor Nerve - recording the Extensor Digitorum Brevis
Origin:  L5-S1 roots, sacral plexus, sciatic nerve, peroneal nerveRecording Site:  Extensor Digitorum Brevis muscle (EDB)Reference Site:  Top of foot below the 4th and 5th toesGround:  Top of footStimulation Sites:  Ankle, below fibular neck and kneeProcedure: ...
 
Peroneal Motor Nerve - recording the Tibialis Anterior
Origin:  L4-L5 roots, sacral plexus, sciatic nerve, peroneal nerveRecording Site:  Tibialis Anterior muscle (TA)Reference Site:  Top of AnkleGround:  Medial lower legStimulation Sites:  Below the fibular head and kneeProcedure:  The recording electrode is placed over the belly of the TA...
 
Tibial Motor Nerve - recording the Abductor Hallucis
Origin:  S1-S2 roots, sacral plexus, sciatic nerve, tibial nerve.Recording Site:  Abductor Hallucis muscle (AH)Reference Site:  Base of big toeGround:  Top of footStimulation Sites:  Ankle and kneeProcedure:  The recording electrode is placed over the belly of the AH...
 
Tibial Motor Nerve - recording the Abductor Digiti Quinti Pedis
Origin:  S1-S2 roots, sacral plexus, sciatic nerve, tibial nerveRecording Site:  Abductor Digiti Quinti Pedis muscle (ADQP)Reference Site:  Top of foot below 5th toeGround:  Top of footStimulation Site:  Ankle Procedure:  The recording electrode is placed over the belly of the ADQP...
 
Femoral Motor Nerve - recording the Rectus Femoris.
Origin:  L2-L4 roots, lumbar plexus, femoral nerveRecording Site:  Rectus Femoris muscle (Rec Fem)Reference Site:  Distal thighGround:  Medial thighStimulation Site:  GroinProcedure:  The recording electrode is placed over the belly of the Rec Fem. ...
 
H-Reflex - recording the Soleus
Origin:  S1, sacral plexus, sciatic nerve, tibial nerve.Recording Site:  Soleus Reference Site:  Achilles tendon, just above the ankleGround:  Back of leg, halfway between the knee and recording site Procedure:  The patient should be placed in the prone...
 
Facial Motor Nerve – recording the Orbicularis Oculi
Origin:  Brainstem facial nucleus, facial nerveRecording Site:  Orbicularis OculiReference Site:  Outer canthusGround:  ForeheadStimulation Site:  Front of Lower ear.Procedure:  The recording electrode is placed over the orbicularis oculi muscles, midpoint, just below the lower lid...
 
Repetitive Nerve Stimulation for Myasthenia Gravis (post-synaptic neuromuscular junction defect)
The most common slow repetitive stimulation studies are recorded from the  Median (APB), Ulnar (ADM), Spinal Accessory (Trapezius) and the Facial (Orbicularis Oculi) motor nerves.  However, myasthenia gravis repetitive stimulation studies can be performed on any motor point...
 
Repetitive Stimulation for Lambert-Eaton Syndrome (pre-synaptic neuromuscular junction defect)
The most common rapid repetitive stimulation studies are recorded from the Median (APB) or Ulnar (ADM) motor nerves.  However, rapid repetitive stimulation studies can be performed on any motor nerve.After performing the routine motor nerve conduction study...
 
Saphenous Sensory Nerve – recording anterior to the Medial Malleolus (antidromic)
Origin:  L3-4 roots, lumbar plexus, femoral nerveRecording Site:  Lower calf at ankle (bar electrode)Reference Site:  Lower calf at ankle (bar electrode)Ground:  Lower legStimulation Site:  CalfProcedure:  The recording and reference electrodes...
 
Unstructured mini-core, electron micrograph (image)

 
Normal skeletal muscle, H&E stained section of paraffin embedded tissue x 100 (image)

 
Normal skeletal muscle, H&E stained frozen section x 100 (image)

 
Normal skeletal muscle, ATPase stain x 100 (image)

 
Normal skeletal muscle, cytochrome oxidase stain x 100 (image)

 
All Muscles
Muscles:    abductor digiti minimi    abductor pollicis brevis    anconeus    biceps brachii    brachioradialis    cervical paraspinal muscles    deltoid     extensor carpi radialis longus     extensor carpi ulnaris    extensor digitorum ...
 
Semitendonosus
Muscle Name: semitendonosusAKA:  musculus semitendinosusAbbreviation: STSpinal Nerve Roots:    L4    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    sciatic nerve (tibial division)Proximal Attachment:  ischial tuberosityDistal Attachment: ...
 
Semimembranosus
Muscle Name: semimembranosusAKA:  musculus semimembranosusAbbreviation: SMSpinal Nerve Roots:    L4    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    sciatic nerve (tibial division)Proximal Attachment:  Ischial tuberosityDistal Attachment: ...
 
Rectus Femoris
Muscle Name: rectus femorisAKA:  Abbreviation: RFSpinal Nerve Roots:    L2    L3    L4Plexus:    lumbar plexusNamed Nerves:    femoral nerveProximal Attachment:  Anterior inferior iliac spine and the acetabulumDistal Attachment:  Patellar tendonAction:...
 
Peroneus Longus
Muscle Name: peroneus longusAKA:  musculus peroneus longusAbbreviation: PLSpinal Nerve Roots:    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    superficial peroneal nerve    common peroneal nerve    sciatic nerveProximal Attachment:  ...
 
Iliacus
Muscle Name: iliacusAKA:  musculus iliacusAbbreviation: IPSpinal Nerve Roots:    L2    L3    L4Plexus:    lumbar plexusNamed Nerves:    femoral nerveProximal Attachment:  Iliiac fossaDistal Attachment:  Lesser trochanter of the femurAction: Flexion...
 
Gluteus Maximus
Muscle Name: gluteus maximusAKA:  musculus gluteus maximusAbbreviation: GMAXSpinal Nerve Roots:    L5    S1    S2Plexus:    lumbosacral plexusNamed Nerves:    inferior gluteal nerveProximal Attachment:      Gluteal surface of ilium, lumbar...
 
Gluteus Medius
Muscle Name: gluteus mediusAKA: musculus gluteus medius Abbreviation: GMEDSpinal Nerve Roots:    L4    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    superior gluteal nerveProximal Attachment:  The gluteal surface of the ilium, deep to the gluteus maximus...
 
Gastrocnemius - Medial Head
Muscle Name: gastrocnemius - medial headAKA:  Abbreviation: MGSpinal Nerve Roots:    S1    S2Plexus:    lumbosacral plexusNamed Nerves:    tibial nerve    sciatic nerveProximal Attachment:  Medial condyle of the femur.Distal Attachment:  CalcaneusAction:...
 
Gastrocnemius - Lateral Head
Muscle Name: gastrocnemius - lateral headAKA:  Abbreviation: LGSpinal Nerve Roots:    S1    S2Plexus:    lumbosacral plexusNamed Nerves:    tibial nerve    sciatic nerveProximal Attachment:  Lateral condyle of the femurDistal Attachment:  CalcaneusAction:...
 
Flexor Digitorum Longus
Muscle Name: flexor digitorum longusAKA:  Abbreviation: FDLSpinal Nerve Roots:    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    tibial nerve    sciatic nerveProximal Attachment:  Posterior surface of the tibia.Distal Attachment:  Base...
 
Extensor Hallucis Longus
Muscle Name: extensor hallucis longusAKA:  musculus extensor hallucis longusAbbreviation: EHLSpinal Nerve Roots:    L4    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    deep peroneal nerve    common peroneal nerve    sciatic nerveProximal...
 
Biceps Femoris - Short Head
Muscle Name: biceps femoris - short headAKA:  Abbreviation: BF-SHSpinal Nerve Roots:    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    sciatic nerve (peroneal division)Proximal Attachment: Lateral edge of the linea aspera and the upper portion of the supracondylar line...
 
Biceps Femoris - Long Head
Muscle Name: biceps femoris - long headAKA:  musculus biceps femoris longusAbbreviation: BF-LHSpinal Nerve Roots:    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    sciatic nerve (tibial division)Proximal Attachment:  ischial tuberosity and...
 
Adductor Longus
Muscle Name: adductor longusAKA:  Abbreviation: ALSpinal Nerve Roots:    L2    L3    L4Plexus:    lumbar plexusNamed Nerves:    obturator nerveProximal Attachment:  pubic crestDistal Attachment:  into the mid lenea aspera between the adductor...
 
Named Nerves
    Axillary Nerve    Femoral Nerve     Gluteal Nerve    Inferior Gluteal Nerve            Superior Gluteal Nerve      Obturator nerve     Median Nerve     Musculocutaneous Nerve     Peroneal Nerve       Common Peroneal...
 
Lower Extremity
    abductor digiti quinti pedis     abductor hallucis brevis     adductor longus     biceps femoris - long head     biceps femoris - short head     extensor digitorum brevis     extensor digitorum longus     extensor hallucis longus    ...
 
Extensor Digitorum Brevis
Muscle Name: extensor digitorum brevisAKA:  musculus extensor digitorum brevisAbbreviation: EDBSpinal Nerve Roots:    L4    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    deep peroneal nerve    common peroneal nerve    sciatic nerveProximal...
 
Abductor Hallucis Brevis
Muscle Name: abductor hallucis brevisAKA:  musculus abductor hallucisAbbreviation: AHBSpinal Nerve Roots:    S1    S2Plexus:    lumbosacral plexusNamed Nerves:    medial plantar nerve    tibial nerve    sciatic nerveProximal Attachment:  Tuberosity...
 
Abductor Digiti Quinti Pedis
Muscle Name: abductor digiti quinti pedisAKA:  Abductor digiti minimi pedis, Abductor minimi digiti, Abductor digiti quinti, musculus abductor digiti minimi pedisAbbreviation: ADQPSpinal Nerve Roots:    S1    S2Plexus:    lumbosacral plexusNamed Nerves: ...
 
Tensor Fasciae Latae
Muscle Name: tensor fasciae lataeAKA:  Abbreviation: TFLSpinal Nerve Roots:    L4    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    superior gluteal nerveProximal Attachment:  Distal Attachment:  Action: ...Needle Insertion: ...Activation for EMG:  Pitfalls:  Notes:  
 
Vastus Lateralis
Muscle Name: vastus lateralisAKA:  Abbreviation: VLSpinal Nerve Roots:    L2    L3    L4Plexus:    lumbar plexusNamed Nerves:    femoral nerveProximal Attachment:  Distal Attachment:  Action: ...Needle Insertion: ...Activation for EMG:  Pitfalls:  Notes:  
 
Spinal Nerve Roots
Choose A Spinal Segment:  Cervical:    C1    C2    C3    C4    C5    C6    C7    C8  Thoracic:    T1    C2    C3    C4    C5    C6    C7    C8    C9    C10    C11    C12  Lumbar:    L1    L2    L3    L4 ...
 
Tibialis Anterior
Muscle Name: tibialis anteriorAKA:  Abbreviation: TASpinal Nerve Roots:    L4    L5Plexus:    lumbosacral plexusNamed Nerves:    deep peroneal nerve    common peroneal nerve    sciatic nerveProximal Attachment:  Distal Attachment:  Action: ...
 
Extensor Digitorum Longus
Muscle Name: extensor digitorum longusAKA:  musculus extensor digitorum longusAbbreviation: EDLSpinal Nerve Roots:    L4    L5    S1 Plexus:    lumbosacral plexusNamed Nerves:    deep peroneal nerve    common peroneal nerve    sciatic nerveProximal...
 
Flexor Hallucis Brevis
Muscle Name: flexor hallucis brevisAKA:  musculus flexor hallucis brevisAbbreviation: FHBSpinal Nerve Roots:    S1    S2Plexus:    lumbosacral plexusNamed Nerves:    medial plantar nerve    tibial nerve    sciatic nerveProximal Attachment:  ...
 
Soleus
Muscle Name: soleusAKA:  Abbreviation: SOLSpinal Nerve Roots:    S1    S2Plexus:    lumbosacral plexusNamed Nerves:    tibial nerve    sciatic nerveProximal Attachment:  Distal Attachment:  Action: ...Needle Insertion: ...Activation for EMG:  Pitfalls:  Notes:  
 
Tibialis Posterior
Muscle Name: tibialis posteriorAKA:  Abbreviation: TPSpinal Nerve Roots:    L5    S1Plexus:    lumbosacral plexusNamed Nerves:    tibial nerve    sciatic nerveProximal Attachment:  Distal Attachment:  Action: ...Needle Insertion: ...Activation for EMG:  Pitfalls:  Notes:  
 
Vastus Medialis
Muscle Name: vastus medialisAKA:  Abbreviation: VMSpinal Nerve Roots:    L2    L3    L4Plexus:    lumbar plexusNamed Nerves:    femoral nerveProximal Attachment:  Distal Attachment:  Action: ...Needle Insertion: ...Activation for EMG:  Pitfalls:  Notes:  
 
Pectoralis Major EMG technique (video)

 
Sternocleidomastoid
Muscle Name: sternocleidomastoidAKA:   Abbreviation: SCM Spinal Nerve Roots:Brachial Plexus Trunks: NABrachial Plexus Cords: NA     Named Nerves: Accessory nerve      Proximal Attachment:   Distal Attachment:   Action:    Needle Insertion:   ...
 
Serratus Anterior
Muscle Name: serratus anteriorAKA:   Abbreviation:  Spinal Nerve Roots:    C5    C6    C7Brachial Plexus Trunks: NABrachial Plexus Cords:  NANamed Nerves:    long thoracic nerve Proximal Attachment:   Surface of the upper 8 ribs.Distal Attachment:  ...
 
Rhomboid
Muscle Name: RhomboidAKA:   musculus rhomboideus majorAbbreviation:  Spinal Nerve Roots:    C4    C5Brachial Plexus Trunks: NABrachial Plexus Cords: NA    Named Nerves: dorsal scapular nerve Proximal Attachment:   Spinous processes of the T2 to...
 
Rhomboids highlighted. (image)

 
Rhomboid (image)

 
Triceps
Muscle Name: tricepsAKA:  musculus triceps brachiiAbbreviation:  Spinal Nerve Roots:    C6    C7    C8Brachial Plexus Trunks:    upper trunk    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal...
 
Pectoralis Major
Muscle Name: pectoralis majorAKA:   Musculus pectoralis majorAbbreviation:  Spinal Nerve Roots:    C5     C6     C7    C8    T1 Brachial Plexus Trunks:    upper trunk    middle trunk    lower trunkBrachial Plexus Cords:    medial cord...
 
Pectoralis Major (image)

 
Latissimus Dorsi
Muscle Name: latissimus dorsi AKA:   musculus latissimus dorsiAbbreviation:  Spinal Nerve Roots:     C6      C7      C8 Brachial Plexus Trunks:    upper trunk    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves: ...
 
Infraspinatus
Muscle Name: InfraspinatusAKA:   Abbreviation:  Spinal Nerve Roots:     C5    C6Brachial Plexus Trunks: upperBrachial Plexus Cords:  NANamed Nerves: suprascapular nerve      Proximal Attachment:   infraspinous fossa of the scapulaDistal Attachment:  ...
 
This cartoon shows the infraspinaous muscles highlighted. (image)

 
Muscles connecting the upper extremity to the vertebral column. (image)

 
Cervical Paraspinal Muscles
Muscle Name: cervical paraspinal musclesAKA:   Abbreviation:  Spinal Nerve Roots:           Innervated by the dorsal rami of the corresponding spinal level.Brachial Plexus Trunks: NABrachial Plexus Cords: NA     Named Nerves: NA      Attachment:...
 
EMG Tutorial
A searchable, illustrated tutorial for electrodiagnsotic studies, by Steven Arbogat, D.O., and J. Douglas Miles, M.D., Ph.D.This tutorial covers both nerve conduction studies (NCS) and electromyography (EMG). We have attempted to organize the tutorial in a...
 
Upper Trapezius EMG Technique (video)

 
Trapezius
Muscle Name: trapeziusAKA:   Abbreviation:  Spinal Nerve Roots:           Brachial Plexus Trunks:Brachial Plexus Cords:     Named Nerves:      Proximal Attachment:   Distal Attachment:   Action:    Needle Insertion:    Activation for EMG:    Pitfalls:  Notes:    
 
Teres Minor EMG Technique (video)

 
Teres Minor
Muscle Name: teres minorAKA:  Abbreviation:  Spinal Nerve Roots:    C5    C6Brachial Plexus Trunks:    upper trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    axillary nerveProximal Attachment:   Distal Attachment:   Action:   ...
 
Supraspinatus EMG Technique (video)

 
Supraspinatus
Muscle Name: supraspinatusAKA:   Abbreviation:  Spinal Nerve Roots:           Brachial Plexus Trunks:Brachial Plexus Cords:     Named Nerves:      Proximal Attachment:   Distal Attachment:   Action:    Needle Insertion:    Activation for EMG:    Pitfalls:  Notes:    
 
Sternocleidomastoid EMG Technique (video)

 
Serratus Anterior EMG Technique (video)

 
Latissimus Dorsi EMG Technique (video)

 
Infraspinatus activation Technique (video)

 
Infraspinatus EMG Technique (video)

 
Lower Cervical Paraspinal Muscles EMG Technique (video)

 
Middle Cervical Paraspinal Muscles EMG Technique (video)

 
Upper Cervical Paraspinal Muscles EMG Technique (video)

 
Posterior Deltoid EMG Technique - Method 2 (video)

 
Posterior Deltoid EMG Technique - Method 1 (video)

 
Anterior Deltoid EMG Technique (video)

 
Rhomboid EMG Technique (video)

 
Pronator Quadratus
Muscle Name: pronator quadratusAKA:  musculus pronator quadratusAbbreviation:  PQSpinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    medial cord    lateral cordNamed Nerves: ...
 
Facial Mononeuropathy/Bell’s Palsy
Facial Mononeuropathy/Bell’s PalsyNerve            Recording Sites        Stimulation SitesFacial (m) bilat    Orbicularis Oculi        earBlink Reflexes bilat    Orbicularis Oculi        supraorbital notchNeedle ExaminationPerform...
 
Phrenic Mononeuropathy
Phrenic MononeuropathyNerve            Recording Sites        Stimulation SitesPhrenic (m) bilat    xyphoid process        anterior neckNeedle ExaminationNeedle exam is not usually performed.
 
Myopathy
MyopathyNerve             Recording Sites        Stimulation Sites         F-WavesMedian (s)         index                wrist       orRadial (s)         thumb                  forearmMedian...
 
Peripheral Neuropathy/Motor Neuron Disease
Peripheral Neuropathy/Motor Neuron DiseaseNerve            Recording Sites        Stimulation Sites          F-WavesMedian (s)        index and middle        wristUlnar (s)        5th                wristRadial...
 
Lumbosacral Plexopathy
Lumbosacral PlexopathyNerve            Recording Sites        Stimulation Sites           F-WavesSural (s) bilat        ankle                calfSup Peron (s) bilat    ankle                lat legPeroneal...
 
Sciatic Mononeuropathy
Needle ExaminationPerform needle exam on the symptomatic limb.  Test the minimum of once muscle innervated by the L2, L3, L4, L5 and S1 spinal roots (see Appendix C).  Test the lumbosacral paraspinal muscles at one or more levels.If abnormalities are detected,...
 
Tarsal Tunnel Syndrome
arsal Tunnel SyndromeNerve            Recording Sites        Stimulation Sites     F-Waves    Sural (s)        ankle                calfSup Peron (s)    ankle                lat legMed Plantar(s) bilat  ...
 
Femoral Mononeuropathy
Femoral MononeuropathyNerve            Recording Sites        Stimulation Sites          F-WavesSural (s)        ankle                calfSup Peron (s)    ankle                lat legSaphenous (s) bilat  ...
 
Peroneal Mononeuropathy
Peroneal MononeuropathyNerve            Recording Sites        Stimulation Sites                F-WavesSural (s)        ankle                calfSup Peron (s) bilat    ankle                lat legPeroneal...
 
Routine Lower Extremity Back/Leg Pain and Lumbosacral Root Search
LOWER EXTREMITYRoutine Lower Extremity Back/Leg Pain and Lumbosacral Root SearchNerve            Recording Sites        Stimulation Sites            F-WavesSural (s)        ankle                calf    Sup Peron...
 
Other Upper Extremity Mononeuropathies (Axillary, Musculocutaneous, Suprascapular, Spinal Accessory, etc…)
Nerve Conductions Studies Median sensory recording the index and middle fingers.Ulnar sensory recording the ring finger. Radial sensory recording the dorsal thumb.Lateral antebrachial cutaneous sensory recording the forearm.Median motor recording the abductor pollicis brevis with F-Waves...
 
Radial Mononeuropathy
Nerve Conductions Studies Median sensory recording the index and middle fingers. Ulnar sensory recording the ring finger.  Radial sensory recording the bilateral dorsal thumbs.Median motor recording the abductor pollicis brevis with F-Waves.Ulnar motor recording...
 
Neck/Arm pain and root search
Nerve Conductions StudiesMedian sensory recording the index and middle fingers. Ulnar sensory recording the ring finger.  Radial sensory recording the dorsal thumb.Median motor recording the abductor pollicis brevis with F-Waves.Ulnar motor recording the...
 
Ulnar Mononeuropathy
Median sensory recording index and middle  fingers.Ulnar sensory recording the llittle  finger.Radial sensory recording the dorsal thumb.Dorsal Ulnar sensory recording the dorsum of the handMedian motor recording the abductor pollicis brevis with F-Waves...
 
Carpal Tunnel Syndrome
Nerve Conductions StudiesMedian sensory recording the  index and middle  fingers. Ulnar sensory recording the llittle finger.Radial sensory recording the dorsal thumb. Median motor recording the abductor pollicis brevis with F-Waves. Ulnar motormotor recording...
 
Brachial Plexopathy (including Thoracic Outlet Syndrome)
Brachial Plexopathy (including Thoracic Outlet Syndrome)Median sensory recording the bilateral  index and middle fingers.Median sensory recording the bilateral thumbs.Ulnar sensory recording the bilateral llittle fingers.Radial sensory recording the bilateral dorsal thumbs...
 
Repetitive Stimulation for Lambert-Eaton Syndrome (pre-synaptic neuromuscular junction defect)
The most common rapid repetitive stimulation studies are recorded from the Median (APB) or Ulnar (ADM) motor nerves.  However, rapid repetitive stimulation studies can be performed on any motor nerve.After performing the routine motor nerve conduction study...
 
Repetitive Nerve Stimulation for Myasthenia Gravis (post-synaptic neuromuscular junction defect)
The most common slow repetitive stimulation studies are recorded from the  Median (APB), Ulnar (ADM), Spinal Accessory (Trapezius) and the Facial (Orbicularis Oculi) motor nerves.  However, myasthenia gravis repetitive stimulation studies can be performed on any motor point...
 
Facial Motor Nerve – recording the Orbicularis Oculi
Origin:  Brainstem facial nucleus, facial nerveRecording Site:  Orbicularis OculiReference Site:  Outer canthusGround:  ForeheadStimulation Site:  Front of Lower ear.Procedure:  The recording electrode is placed over the orbicularis oculi muscles, midpoint, just below the lower lid...
 
H-Reflex - recording the Soleus
Origin:  S1, sacral plexus, sciatic nerve, tibial nerve.Recording Site:  Soleus Reference Site:  Achilles tendon, just above the ankleGround:  Back of leg, halfway between the knee and recording site Procedure:  The patient should be placed in the prone...
 
Femoral Motor Nerve - recording the Rectus Femoris.
Origin:  L2-L4 roots, lumbar plexus, femoral nerveRecording Site:  Rectus Femoris muscle (Rec Fem)Reference Site:  Distal thighGround:  Medial thighStimulation Site:  GroinProcedure:  The recording electrode is placed over the belly of the Rec Fem. ...
 
Tibial Motor Nerve - recording the Abductor Digiti Quinti Pedis
Origin:  S1-S2 roots, sacral plexus, sciatic nerve, tibial nerveRecording Site:  Abductor Digiti Quinti Pedis muscle (ADQP)Reference Site:  Top of foot below 5th toeGround:  Top of footStimulation Site:  Ankle Procedure:  The recording electrode is placed over the belly of the ADQP...
 
Tibial Motor Nerve - recording the Abductor Hallucis
Origin:  S1-S2 roots, sacral plexus, sciatic nerve, tibial nerve.Recording Site:  Abductor Hallucis muscle (AH)Reference Site:  Base of big toeGround:  Top of footStimulation Sites:  Ankle and kneeProcedure:  The recording electrode is placed over the belly of the AH...
 
Peroneal Motor Nerve - recording the Tibialis Anterior
Origin:  L4-L5 roots, sacral plexus, sciatic nerve, peroneal nerveRecording Site:  Tibialis Anterior muscle (TA)Reference Site:  Top of AnkleGround:  Medial lower legStimulation Sites:  Below the fibular head and kneeProcedure:  The recording electrode is placed over the belly of the TA...
 
Peroneal Motor Nerve - recording the Extensor Digitorum Brevis
Origin:  L5-S1 roots, sacral plexus, sciatic nerve, peroneal nerveRecording Site:  Extensor Digitorum Brevis muscle (EDB)Reference Site:  Top of foot below the 4th and 5th toesGround:  Top of footStimulation Sites:  Ankle, below fibular neck and kneeProcedure: ...
 
Saphenous Sensory Nerve – recording anterior to the Medial Malleolus (antidromic)
Origin:  L3-4 roots, lumbar plexus, femoral nerveRecording Site:  Lower calf at ankle (bar electrode)Reference Site:  Lower calf at ankle (bar electrode)Ground:  Lower legStimulation Site:  CalfProcedure:  The recording and reference electrodes...
 
Saphenous Sensory Nerve – recording anterior to the Medial Malleolus (antidromic)
Origin:  L3-4 roots, lumbar plexus, femoral nerveRecording Site:  Lower calf at ankle (bar electrode)Reference Site:  Lower calf at ankle (bar electrode)Ground:  Lower legStimulation Site:  CalfProcedure:  The recording and reference electrodes (bar...
 
Denervation atrophy of skeletal muscle, NADH-TR (image)

 
Polymyositis, paraffin-embedded H. E. stained section x 200 (image)

 
Polymyositis, immunohistochemical staining for CD68 x600 (image)

 
Perivascular infiltrate, H&E stained paraffin embedded section x400 (image)

 
Perivascular infiltrate, H&E stained section of paraffin embedded skeletal muscle x200 (image)

 
Paraneoplastic myositis, H&E stained section (image)

 
Dermatomyositis, H&E stained sections of paraffin embedded skeletal muscle (image)

 
Dermatomyositis, H&E stained section of frozen skeletal muscle x 100 (image)

 
Dermatomyositis, H&E stained section of paraffin embedded muscle x 200 (image)

 
Dermatomyositis, H&E stained section of paraffin embedded skeletal muscle x 400 (image)

 
Churg Strauss arteritis on muscle biopsy, H&E stained section x 40 (image)

 
Churg strauss arteritis involving skeletal muscle, H&E stain x 100 (image)

 
Inclusion body myositis, Gomori trichrome stain x 400 (image)

 
Inclusion body myositis, H&E stain x400 (image)

 
Inclusion body myositis, SMI-31 immunohistochemical stain x 400 (image)

 
Inclusion body myositis, Gomori trichrome stained frozen muscle x 200 (image)

 
Inclusion body myositis, trichrome stain, low-power. (image)

 
Myopathy with tubular aggregates, H&E stain x 200 (image)

 
Congenital Fiber Type Disproportion
The defining feature of congenital fiber type disproportion (CFTD) is type 1 muscle fibers which are at least 12% smaller than type 2 muscle fibers. CNS abnormalities and developmental delay may be present. Severity of clinical weakness correlates with smallness of type 1 fibers...
 
Centronuclear myopathy, H&E stained section of paraffin embedded skeletal muscle x 200 (image)

 
Central cord disease, NADH-TR histochemical stain (image)

 
Central cord disease, cytochrome oxidase stain (image)

 
Nemaline myopathy, trichrome stained frozen section of muscle x 200 (image)

 
Calpainopathy, paraffin-embedded H&E stained section x 400 (image)

 
Calpainopathy, paraffin-embedded H&E stained section of muscle x 200 (image)

 
Calpainopathy, frozen section of muscle, H&E stain x 200. (image)

 
Titinopathy, paraffin-embedded H&E stained section of muscle x 200 (image)

 
Ring fibers, trichrome staining of muscle (image)

 
Ring fibers, NADH-TR histochemical staining (image)

 
Ring fibers, H&E stain section (image)

 
Necrotizing myopathy in a patient with rhabdomyolysis, H&E stained section x 400 (image)

 
Myofibrillary myopathy, H&E stained slide x 100 (image)

 
Spinal Accessory Motor Nerve - recording the Trapezius
Origin:  C2-C4 roots, cervical plexus, spinal accessory nerve.Recording Site:  TrapeziusReference Site:  ShoulderGround:  Upper backStimulation Site:  Posterior neckProcedure:  The recording electrode is placed on the belly of the trapezius muscle. ...
 
Axillary Motor Nerve - recording the Deltoid
Origin:  C5-6 roots, upper trunk and posterior cord of the brachial plexus, axillary nerve.Recording Site:  Deltoid muscleReference Site:  Distal upper armGround:  ShoulderStimulation Sites:  Erb’s PointProcedure:  The recording electrode is placed...
 
Musculocutaneous Motor Nerve - recording the Biceps
Origin:  C5-6 roots, upper trunk and lateral cord of the brachial plexus, Musculocutaneous nerve.Recording Site:  Biceps muscleReference Site:  Distal upper armGround:  Upper armStimulation Site:  Axilla and Erb’s point.Procedure:  The recording electrode...
 
Radial Motor Nerve - Recording the Extenor Digitorum Communis (EDC)
Origin:  C7-C8 roots, middle and lower trunk and posterior cord of the brachial plexus, radial nerve.Recording Site:  Extensor Digitorum Communis muscle (EDC)Reference Site:  Above the wristGround:  Medial forearmStimulation Sites:  Elbow and arm (below...
 
Ulnar Motor Nerve - Recording the Abductor Digiti Minimi (ADM)
Origin:  C8-T1 roots, lower trunk and medial cord of the brachial plexus, ulnar nerveRecording Site:  Abductor Digiti Minimi muscle (ADM)Reference Site:  Base of little fingerGround:  Palm or top of handStimulation Sites:  Wrist, below elbow and above elbow...
 
Median Motor Study - Recording the Abductor Pollicis Brevis
Origin:  C8-T1 roots, lower trunk and medial cord of the brachial plexus, median nerve.Recording Site:  Abductor Pollicis Brevis muscle (APB)Reference Site:  Base of thumbGround:  Palm or top of handStimulation Sites:  Wrist and elbowProcedure:  The...
 
Recommended approaches to common clinical problems.
This section covers our recommended approaches to common conditions the electromyographer is asked to evaluate. Neck/Arm pain and root search  Carpal Tunnel Syndrome 
 
Biceps Brachii
Muscle Name: biceps brachiiAKA: musculus biceps brachii Abbreviation:  BBSpinal Nerve Roots:    C5    C6Brachial Plexus Trunks:    upper trunkBrachial Plexus Cords:    lateral cordNamed Nerves:    musculocutaneous nerveProximal Attachment:  coracoid process of the scapula...
 
Supinator
Muscle Name: supinatorAKA:  Musculus supinatorAbbreviation:  Spinal Nerve Roots:    C6    C7Brachial Plexus Trunks:    upper trunk    middle trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal Attachment:  Lateral...
 
Supinator with arrow (image)

 
Supinator with arrow (image)

 
Supinator Anterior view (image)

 
pronator quadratus highlighted (image)

 
Pronator Quadratus (image)

 
First Dorsal Interosseous
Muscle Name: first dorsal interosseousAKA:  Abbreviation:  FDISpinal Nerve Roots:    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    ulnar nerveProximal Attachment:  metacarpal bone.Distal Attachment:  proximal phalanx on the first digit...
 
First Dorsal Interosseous (image)

 
Flexor Pollicis Brevis
Muscle Name: flexor pollicis brevisAKA:  musculus flexor pollicis brevisAbbreviation: FPB Spinal Nerve Roots:    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    median nerve    ulnar nerveProximal...
 
Flexor Digitorum Profundus To Digit 5
Muscle Name: flexor digitorum profundus to digit 5AKA:  musculus flexor digitorum profundus Abbreviation:  FDP5Spinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:   ...
 
Flexor Digitorum Profundus To Digit 4
Muscle Name: flexor digitorum profundus to digit 4AKA:  musculus flexor digitorum profundus Abbreviation:  FDP4Spinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    ulnar...
 
Flexor Digitorum Profundus To Digit 2
Muscle Name: flexor digitorum profundus to digit 2AKA:  musculus flexor digitorum profundusAbbreviation:  FDP2Spinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    median...
 
Flexor Digitorum Profundus To Digit 3
Muscle Name: flexor digitorum profundus to digit 3AKA:  musculus flexor digitorum profundusAbbreviation:  FDP3Spinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    median...
 
Flexor Carpi Ulnaris
Muscle Name: flexor carpi ulnarisAKA:  musculus flexor carpi ulnarisAbbreviation:  FCRSpinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    ulnar nerveProximal Attachment: ...
 
Flexor Carpi Radialis
Muscle Name: flexor carpi radialisAKA:  musculus flexor carpi radialisAbbreviation:  FCRSpinal Nerve Roots:    C6    C7Brachial Plexus Trunks:    upper trunk    middle trunkBrachial Plexus Cords:    lateral cordNamed Nerves:    median nerveProximal...
 
Extensor Pollicis Longus
Muscle Name: extensor pollicis longusAKA:  musculus extensor pollicis longusAbbreviation:  EPLSpinal Nerve Roots:    C7    C8Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial...
 
Extensor Pollicis Longus (image)

 
Extensor Pollicis Brevis
Muscle Name: extensor pollicis brevisAKA:  musculus extensor pollicis brevisAbbreviation:  EPBSpinal Nerve Roots:    C7    C8Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial...
 
Extensor Pollicis Brevis (image)

 
Extensor Indicis
Muscle Name: extensor indicisAKA:  musculus extensor indicisAbbreviation:  EIPSpinal Nerve Roots:    C7    C8Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal Attachment: ...
 
Extensor Digitorum Communis
Muscle Name: extensor digitorum communis AKA:  musculus extensor digitorumAbbreviation:  EDCSpinal Nerve Roots:    C7    C8Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal...
 
Extensor Carpi Ulnaris
Muscle Name: extensor carpi ulnarisAKA:  musculus extensor carpi ulnarisAbbreviation:  ECUSpinal Nerve Roots:    C7    C8Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal...
 
Extensor Carpi Radialis Longus
Muscle Name: extensor carpi radialis longusAKA:  Abbreviation:  Spinal Nerve Roots:    C5    C6    C7Brachial Plexus Trunks:    upper trunk    middle trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal Attachment: ...
 
Deltoid
Muscle Name: deltoidAKA: musculus deltoideusAbbreviation:  Spinal Nerve Roots:    C5    C6Brachial Plexus Trunks:    upper trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    axillary nerveProximal Attachment:  clavicle, acromion, spine...
 
Viral Infections
The most common causes of viral meningitis in the U.S. are nonpolio enteroviruses (coxsackie and echovirus), which often occur in summer and early fall. Infection is by the fecal-oral route, with primary viral replication in the GI and upper respiratory tracts...
 
Middle Deltoid EMG Technique (video)

 
Normal Skeletal Muscle - Gomori Trichrome (image)

 
NADH(TR) - normal muscle (image)

 
Periodic Acid Schiff (PAS) stain of normal muscle. (image)

 
Oil red O stain of normal muscle. (image)

 
Extensor Pollicis Longus EMG Technique (video)

 
Extensor Pollicis Brevis EMG Technique (video)

 
Extensor Carpi Radialis Longus EMG Technique (video)

 
Supinator EMG Technique (video)

 
Flexor Digitorum Sublimis, Highlighted (image)

 
ALS
Also referred to as motor neurone disease (by the British), amyotrophic lateral sclerosis (ALS) is a progressive and ultimately fatal disorder characterized by degeneration of the upper and lower motor neurons of the brain and spinal cord. ALS occurs worldwide...
 
Deltoid (image)

 
Brachioradialis
Muscle Name: brachioradialisAKA:  musculus brachioradialisAbbreviation:  Spinal Nerve Roots:    C5    C6Brachial Plexus Trunks:    upper trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal Attachment: Lateral supracondylar...
 
Brachioradialis (image)

 
highlighted_brachioradialis (image)

 
Anconeus highlighted (image)

 
Anconeus (image)

 
Anconeus
Muscle Name: anconeusAKA:  musculus anconeusAbbreviation:  Spinal Nerve Roots:    C6    C7    C8Brachial Plexus Trunks:    upper trunk    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed...
 
Anconeus
Muscle Name: anconeusAKA:  musculus anconeusAbbreviation:  Spinal Nerve Roots:    C6    C7    C8Brachial Plexus Trunks:    upper trunk    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed...
 
Anconeus
Muscle Name: anconeusAKA:  musculus anconeusAbbreviation:  Spinal Nerve Roots:    C6    C7    C8Brachial Plexus Trunks:    upper trunk    middle trunk    lower trunkBrachial Plexus Cords:    posterior cordNamed Nerves:    radial nerveProximal...
 
Abductor Digiti Minimi
Muscle Name: abductor digiti minimiAKA:  musculus abductor digiti minimi manusAbbreviation:  ADMSpinal Nerve Roots:    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    ulnar nerveProximal Attachment: ...
 
Vascular Disease 4: Other topics in vascular disease
Working from the outside in, intracranial hemorrhage may be epidural, subdural, subarachnoid, intraparechymal, or intraventricular in origin (though many do not remain localized to a single compartment). The term “hemorrhagic stroke” only applies to subarachnoid and intraparenchymal hemorrhages...
 
Viral Encephalitis
A. Herpes Simplex Virus Type 1 Encephalitis 1. Pathogenesis HSV-1 encephalitis is the most common cause of acute sporadic encephalitis in the U.S. It typically causes lip and mouth lesions (herpes labialis and stomatitis). Note the distinction from HSV-2,...
 
Needle EMG Studies
A searchable, illustrated tutorial for electromyography (EMG). Describes innervation, anatomy, appropriate needle placement, and activation techniques for muscles commonly studied using EMG.
 
Ragged Red Fiber, Trichrome stain (image)

 
Tubular aggregate, Gomori trichrome stain x 400 (image)

 
CADASIL, H&E stain x 400 (image)

 
Transtentorial herniation, close up view of ventral surface of brain. (image)

 
Triceps Brachii EMG Technique (video)

 
Opponens Pollicis EMG Technique (video)

 
Flexor Pollicis Brevis EMG Technique (video)

 
Flexor Digitorum Superficialis EMG Technique (video)

 
Flexor Digitorum Profundus To Digit 2 EMG Technique (video)

 
Flexor Digitorum Profundus To Digit 3 EMG Technique (video)

 
Flexor Digitorum Profundus To Digit 4 EMG Technique (video)

 
Flexor Digitorum Profundus To Digit 5 EMG Technique (video)

 
Flexor Carpi Radialis EMG Technique (video)

 
Extensor Carpi Ulnaris EMG Technique (video)

 
Pronator Teres EMG Technique (video)

 
Pronator Quadratus (video)

 
Flexor Carpi Ulnaris (video)

 
Extensor Digitorum EMG Technique (video)

 
Brachioradialis EMG Technique (video)

 
Biceps Brachii EMG Technique (video)

 
Anconeus EMG Technique (video)

 
Abductor Pollicis Brevis EMG Technique 2 (video)

 
The muscles of the palmar surface of the left hand. (image)

 
Opponens Pollicis
Muscle Name: opponens pollicisAKA:  Abbreviation:  Spinal Nerve Roots:    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    median nerveProximal Attachment: Trapezium and transverse carpal ligament...
 
Opponens pollicis highlighted (image)

 
Abductor Pollicis Brevis
Muscle Name: abductor pollicis brevisAKA:  Abbreviation: APBSpinal Nerve Roots:    C8    T1Brachial Plexus Trunks:    lower trunkBrachial Plexus Cords:    medial cordNamed Nerves:    median nerveProximal Attachment: Transverse carpal ligament, the...
 
Flexor Digitorum Superficialis (image)

 
Flexor Digitorum Superficialis
Muscle Name: flexor digitorum superficialisAKA:  Flexor digitorum sublimisAbbreviation:  FDSSpinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    medial cord    lateral cordNamed...
 
Pronator Teres
Muscle Name: pronator teresAKA:  Abbreviation:  Spinal Nerve Roots:    C6    C7Brachial Plexus Trunks:    upper trunk    middle trunkBrachial Plexus Cords:    lateral cordNamed Nerves:    median nerveProximal Attachment: Humeral head: medial...
 
Flexor Carpi Radialis highlighted (image)

 
Flexor Carpi Radialis highlighted (image)

 
Biceps Brachii with arrow (image)

 
Flexor Carpi Radialis with arrow (image)

 
First Dorsal Interosseous Muscle, Highlighted (image)

 
Abductor Pollicis Brevis (APB) Muscle Highlighted (image)

 
Triceps with arrow (image)

 
Median Nerve
Nerve: Median NerveMuscles Innervated:    pronator teres    flexor carpi radialis    flexor digitorum superficialis    abductor pollicis brevis    opponens pollicis    pronator quadratus    flexor digitorum profundus to digit 2    flexor digitorum...
 
Lateral Cord of the Brachial Plexus
Cord: Lateral CordMuscles Innervated:    pronator teres    flexor carpi radialis    flexor digitorum superficialis    pronator quadratus    flexor pollicis longus     biceps brachii
 
Triceps (image)

 
Medial Cord of the Brachial Plexus
Cord: Medial CordMuscles Innervated:    flexor digitorum superficialis    abductor pollicis brevis    opponens pollicis    pronator quadratus    flexor digitorum profundus to digit 2    flexor digitorum profundus to digit 3    flexor pollicis...
 
Lower Trunk of the Brachial Plexus
Trunk: Lower TrunkSpinal Segments:C8, T1Muscles Innervated:    flexor digitorum superficialis    abductor pollicis brevis    opponens pollicis    pronator quadratus    flexor digitorum profundus to digit 2    flexor digitorum profundus to digit...
 
Middle Trunk of the Brachial Plexus
Trunk: Middle TrunkSpinal Segments:C7Muscles Innervated:    pronator teres    flexor carpi radialis    flexor digitorum superficialis    pronator quadratus    flexor pollicis longus     triceps    extensor carpi radialis longus    extensor...
 
Flexor Pollicis Longus
Muscle Name: flexor pollicis longusAKA:  Abbreviation:  FPLSpinal Nerve Roots:    C7    C8    T1Brachial Plexus Trunks:    middle trunk    lower trunkBrachial Plexus Cords:    medial cord    lateral cordNamed Nerves:    anterior interosseous...
 
T1
Spinal Root: T1Muscles Innervated:    flexor digitorum superficialis    abductor pollicis brevis    opponens pollicis    pronator quadratus    flexor digitorum profundus to digit 2    flexor digitorum profundus to digit 3    flexor pollicis brevis ...
 
Flexor Pollicis Longus EMG Technique (video)

 
Extensor Indicis Proprius EMG Technique (video)

 
Abductor Digiti Minimi EMG Technique (video)

 
Abductor Digiti Minimi - Highlighted (image)

 
Abductor Digiti Minimi (image)

 
First Dorsal Interosseous Surface View with arrow (image)

 
First Dorsal Interosseous in Action with arrow (image)

 
Abductor Digiti Minimi Surface View with arrow (image)

 
Abductor Digiti Minimi Surface View (image)

 
First Dorsal Interosseous Surface View (image)

 
First Dorsal Interosseous in Action (image)

 
First Dorsal Interosseous Needle Placement (image)

 
First Dorsal Interosseous EMG Technique (video)

 
Pronator Teres, Highlighted (image)

 
Pronator Teres (image)

 
Abductor Pollicis Brevis EMG Technique (video)

 
Posterior Cord of the Brachial Plexus
Cord: Posterior CordMuscles Innervated:    triceps    brachioradialis    extensor carpi radialis longus    supinator    extensor carpi ulnaris    extensor digitorum    extensor pollicis longus    extensor pollicis brevis    extensor indicis    anconeus    deltoid
 
Musculocutaneous Nerve
Nerve: Musculocutaneous NerveMuscles Innervated:    biceps brachii
 
Axillary Nerve
Nerve: Axillary NerveMuscles Innervated:    deltoid
 
Radial Nerve
Nerve: Radial NerveMuscles Innervated:    triceps    brachioradialis    extensor carpi radialis longus    supinator    extensor carpi ulnaris    extensor digitorum    extensor pollicis longus    extensor pollicis brevis    extensor indicis    anconeus
 
Ulnar Nerve
Nerve: Ulnar NerveMuscles Innervated:    flexor pollicis brevis    flexor carpi ulnaris    flexor digitorum profundus to digit 4    flexor digitorum profundus to digit 5    abductor digiti minimi    first dorsal interosseous
 
Upper Trunk of the Brachial Plexus
Trunk: Upper TrunkSpinal Segments:C5, C6Muscles Innervated:    pronator teres    flexor carpi radialis    triceps    brachioradialis    extensor carpi radialis longus    anconeus    biceps brachii    deltoid
 
C4
Spinal Root: C4Muscles Innervated:
 
Brachial Plexus Trunks
Trunks:    Upper Trunk    Middle Trunk    Lower Trunk
 
Brachial Plexus Cords
Cords:    Medial Cord    Lateral Cord    Posterior Cord
 
C3
Spinal Root: C3Muscles Innervated:
 
Abductor Pollicis Brevis - EMG Demo (video)

 
Insertion point for EMG study of Abductor Pollicis Brevis muscle (image)

 
Abductor Pollicis Brevis with arrow (image)

 
Abductor Pollicis Brevis (image)

 
Abductor Pollicis Brevis
Name: Abductor pollicis brevisAbbreviation: APBAKA:Nerve: MedianCord: MedialDivision: AnteriorTrunk: LowerRoot: C8, T1Insertion: lateral approach to the base of the thumb, insert 1-2 cm in depthAction: Abducts the thumbActivation: Patient moves thumb perpindicular awas from the palm...
 
C8
C8
 
Cavernous angioma, trichrome stained section x 40 (image)

 
Temporal Artery with Amyloid, H&E stain x40 (image)

 
Aneurysm Wall, high power trichrome stain (image)

 
Aneurysm wall, high-power movat pentachrome stain. (image)

 
Aneurysm wall, movat pentachrome stain x 40 (image)

 
Aneurysm wall, H&E stained slide x 40 (image)

 
ATPase - Example of pathological findings (image)

 
Commonly used stains
In this section, we'll go over some of the more commonly used stains in neuropathology.  Different stains might be used in different tissues.  For example, the Gomorri trichrome stain is especially helpful in muscle to find certain types of myopathy...
 
COX (Cytochrome Oxidase) Staining
Cytochrome oxidase (cox) is an oxidative enzyme in the electron transport chain.  Staining for cox is a sensitive method to assess capacity for oxidative metabolism. Type I muscle fibers have a higher capacity for oxidative metabolism than type II cells,...
 
COX - Example of pathological findings (image)

 
Cytochrome Oxidase staining - Example of pathological findings (image)

 
NADH - Example of pathological findings with arrow (image)

 
NADH - Example of pathological findings (image)

 
NADH - Example of pathological findings (image)

 
NADH - Example of pathological findings (image)

 
Structure of Skeletal Muscle - Schematic (image)

 
ATPase - Example of pathological findings (image)

 
Muscle invasion by meningioma, H&E stained section (image)

 
Target fibers: NADH-TR stain (image)

 
Dysferlinopathy x100 (image)

 
Congenital muscular dystrophy x200 (image)

 
Diabetic thigh infarct x200 (image)

 
Tubular Aggregates H&E stain (image)

 
Central core disease: Cytochrome oxidase staining (image)

 
PAS Muscle (image)

 
Example of trichrome stain (image)

 
Gomori Trichrome - Normal Example (image)

 
Neuromuscular Disorders 01
209
 
Denervation, Dystrophy, and Disorders of Energy Metabolism (video)

 
Neuromuscular disorders 1: Myopathies and Dystrophies
There is a wide array of pathology associated with nerve and muscle diseases.  This section will go into categories of muscle and nerve disorders, and certain specific disorders in depth.  Try the most recent additions to this section - an overview by jdmiles...
 
Congenital Muscular Dystrophies
Like the classical congenital myopathies, the muscular dystrophies are genetically determined diseases of skeletal muscle.  Unlike the classical myopathies, there are not unique pathological findings, like nemaline rods or central cores.  So historically,...
 
Congenital Myopathies
There are many types of myopathies, and they can be categorized in many ways.  One category that has clinical utility is the congenital myopathies.  Congenital myopathies are genetic disorders which result in abnormalities in skeletal muscle. This section deals exclusively with congenital myopathies...
 
Myopathy with Tubular Aggregates
Tubular aggregates are a fairly nonspecific finding.  They are found in many muscle disorders, including perioric paralyses, some myotonic disorders, ond some toxic myopathies. Tubular aggreagates look like this (click to enlarge):    References:Katirji, B...
 
Categories of Congenital Myopathies
The congenital myopathies are genetic diseases resulting in skeletal muscle abnormalities.  They are often apparent at birth, but may not manifest symptoms until later in life. Categorization of Congenital Myopathies Since there is considerable overlap in...
 
Reducing Body Myopathy
Reducing Body Myopathy is rare, and has a variable course.The defining feature is the presence of reducing bodies, which are small, roundish bodies that often are found near the nuclei in muscle fibers.  They can be visualized with trichrome.  It's unclear what they are...
 
Multicore Disease / Minicore Disease
Multicore Disease and Minicore Disease are synonymous terms.The disorder they describe is related to, but distinct from, central core disease.  In central core disease, the mitochondria-lacking cores run the whole length of the muscle fiber.  In minicore...
 
Centronuclear Myopathy and Myotubular Myopathy
The terms myotubular myopathy and centronuclear myopathy are sometimes used interchangably.  Myotubular myopathy specifically refers to the infantile, X-linked form of the syndrome.  Centronuclear myopathy is used to describe forms inherited autosomally and with later onset...
 
Centronuclear Myopathy with arrow (image)

 
Nemaline Myopathy
Like many of the congenital myopathies, the features of nemaline myopathy tend to be more severe course if the disease initially presents in infancy.  A more moderate expression of the disease is expected if it presents in childhood.  There is a wide clinical...
 
Centronuclear Myopathy (image)

 
Central Core Disease
Like many of the congenital myopathies, the features of central core disease tend to be more severe course if the disease initially presents in infancy.  A more moderate expression of the disease is expected if it presents in childhood, and the disease relatively...
 
NADH stained skeletal muscle from a patient with CCD. (image)

 
CCD - ATPase with label (image)

 
Central Core Disease - ATPase stain (image)

 
CCD COX with arrow (image)

 
CCD NADH with arrow (image)

 
Nemaline Myopathy (image)

 
NADH - Normal Example (image)

 
EM - Example of pathological findings (image)

 
H&E - Example of pathological findings with arrow (image)

 
H&E - Example of pathological findings (image)

 
Gomori Trichrome
From an aesthetic point of view, the Gomori trichrome is my favorite muscle stain.  It also extremely helpful, and yields an abundance of the information.  A trichrome stain is a stain that highlights different chemical features in three different colors...
 
Tub Agg Trichrome x400 with arrow (image)

 
Gomori Trichrome, showing nemaline rods (image)

 
Gomori Trichrome, showing inclusion bodies (image)

 
IBM trichrome with highlighted rimmed vacuoles (image)

 
CCD COX with arrow (image)

 
Inclusion Body Myositis H&E 200 with arrow (image)

 
Inclusion body myositis trichrome x200 with arrow (image)

 
Tub Agg Trichrome x400 with arrow (image)

 
IBM trichrome with highlighted rimmed vacuoles (image)

 
Inclusion body myositis x400 with arrow (image)

 
Trichrome IBM hp Inclusions (image)

 
Storage diseases

 
Gomori Trichrome Nemaline Rods 2 (image)

 
Gomori Trichrome Nemaline Rods 2 (image)

 
Example of trichrome stain (image)

 



Gallery Images



NMJ

 
Radial Motor NCS, Recording the

 
Radial Motor NCS, Recording the

 
Radial Motor Nerve Conduction St

 
Median Motor Nerve Conduction St

 
Median Motor Nerve Conduction St

 
Median Motor Nerve Conduction St

 
Median Motor Nerve Conduction St

 
Musculocutaneous Motor Nerve Con

 
Musculocutaneous Motor Nerve Con

 
Musculocutaneous Motor Nerve Con

 
Musculocutaneous Motor Nerve Con

 
Musculocutaneous Motor Nerve Con

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - Recording th

 
Ulnar Motor Nerve - ADM 2

 
Radial Motor NCS, Recording the

 
Radial Motor NCS, Recording the

 
Radial Motor NCS, recording from

 
Radial Motor NCS, Placement of e

 
Unstructured mini-core, electron

 
Normal skeletal muscle, H&E sta

 
Normal skeletal muscle, H&E stai

 
Normal skeletal muscle, ATPase s

 
Normal skeletal muscle, cytochro

 
Rhomboids highlighted.

 
This cartoon shows the infraspin

 
Supinator with arrow

 
Supinator with arrow

 
pronator quadratus highlighted

 
Flexor Digitorum Sublimis, Highl

 
highlighted_brachioradialis

 
Anconeus highlighted

 
Opponens pollicis highlighted

 
Flexor Carpi Radialis highlighte

 
Flexor Carpi Radialis highlighte

 
Biceps Brachii with arrow

 
Flexor Carpi Radialis with arrow

 
First Dorsal Interosseous Muscle

 
Abductor Pollicis Brevis (A

 
Triceps with arrow

 
Abductor Digiti Minimi - Highlig

 
First Dorsal Interosseous Surfac

 
First Dorsal Interosseous in Act

 
Abductor Digiti Minimi Surface V

 
Abductor Digiti Minimi Surface V

 
First Dorsal Interosseous Surfac

 
First Dorsal Interosseous in Act

 
First Dorsal Interosseous Needle

 
Insertion point for EMG study of

 
Abductor Pollicis Brevis with ar

 
NADH - Example of pathological f

 
Structure of Skeletal Muscle - S

 
PAS Muscle

 
Meningioma Invading Muscle

 
Calpainopathy FS 200x

 
Gomori Trichrome Normal Muscle

 
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Centronuclear Myopathy with arro

 
Centronuclear Myopathy

 
NADH stained skeletal muscle fro

 
CCD - ATPase with label

 
CCD COX with arrow

 
CCD NADH with arrow

 
NADH - normal muscle

 
H&E - Example of pathological fi

 
Ragged Red Fiber Trichrome

 
CCD COX with arrow

 
IBM trichrome with highlighted r

 
Inclusion body myositis x400 wit

 
Trichrome IBM hp Inclusions

 
Gomori Trichrome Nemaline Rods 2

 
Pronator teres

 
Muscle Cytochrome Oxidase

 
EM IBM

 
EEG artifacts