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Electromyography and Neuromuscular Disorders - Chapter 1 Quiz - Question 2
True or False: There are very few ways in which technical factors can adversely affect the accuracy of nerve conduction studies or EMGs.
 
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
 
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
 
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
 
Ascending Weakness 01
A 19 year-old, previously healthy police officer presents with a 4 day history of worsening ascending weakness, which began shortly after he started complaining of severe abdominal pain. On exam, he is delirious. The cranial nerves appear intact. He has diffuse, symmetric weakness...
 
Release my hand, please!
A 26-year-old man visits the physician's office with excessive day time sleepiness. His face is long, thin, and has bilateral ptoses without frontalis overaction but there no is ocular weakness. He is wearing a wig. Which one of the following is inconsistent with the diagnosis of myotonia dystrophica
 
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
 
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
 
Inborn Errors of Metabolism 03
A 15 year-old female presents with complaints of weakness and progressive difficulties with walking. Physical exam reveals hypotonia and absent patellar and achilles reflexes. An MRI is obtained, and is shown above.Of the following, which is the most likely diagnosis
 
Time Course of EMG/NCS Findings
Sadly, you suffer from anal warts. Your ghoulish surgeon recommends general anesthesia for a surgical resection of the warts. When you awaken, he proudly announces, Congratulations! I have successfully severed your T1 spinal nerve! You are kind of disgruntled...
 
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. 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...
 



User Forums and Comments



QuickTime compatibility added
The videos in the EMG tutorial can now be viewed on the Apple iPad, iPod touch, and other machines that require QuickTime.
 
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...
 



Online Course Content



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...
 
Pages of Text or HTML with images
This kind of resource is more or less what you've been reading this presentation on: hypertext pages wihch mix text, hyperlinks, images and interactive images.Dr. Mark Cohen's lecture on Parkinsonian neurodegenerative diseases is a much stronger example...
 
Videos
Videos are very good for quickly conveying a lot of information, especially about movements.For example, this is the Babinski response: Teaching how to perform electromyography.  Mixing with Face-to-Face LearningDiscussing a topicShow appropriate videoAsk...
 
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 Nerve Conduction Studies
MotorAxillary Motor Nerve - recording the Deltoid  Median and Ulnar motor nerves- Recording the 2nd Lumbrical and interossei Median Motor Study - Recording the Abductor Pollicis Brevis Musculocutaneous Motor Nerve - recording the Biceps  Radial Motor Nerve...
 
Motor Nerve Conduction Studies
Axillary Axillary Motor Nerve - recording the DeltoidFacial Facial Motor Nerve – recording the Orbicularis OculiFemoralFemoral Motor Nerve - recording the Rectus FemorisMedian Median Palmar Mixed Nerve (orthodromic) Median Motor Study - Recording the Abductor...
 
Special Studies
Blink Blink Reflexes – recording the Orbicularis OculiF-waves F-WavesFacial Facial Motor Nerve – recording the Orbicularis OculiH-ReflexH-Reflex - recording the SoleusPhrenic Motor StudyPhrenic Motor Nerve Conduction StudyRepetitive Stimulation Repetitive...
 
Median Sensory Nerve - Recording the middle finger (antidromic)
Median Sensory Nerve - middle (antidromic)Origin:  C7 root, middle trunk and lateral cord of the brachial plexus, median nerveRecording Site:  Middle fingerReference Site:  Middle fingerGround:  Palm or top of handStimulation Site:  WristProcedure: ...
 
Median Sensory Nerve - Recording the thumb (antidromic)
Origin:  C6-C7 root, upper and middle trunk and lateral cord of the brachial plexus, median nerve.Recording Site:  ThumbReference Site:  ThumbGround:  Palm or top of handStimulation Site:  WristProcedure:  The recording electrode is placed on the proximal phalanx of the thumb...
 
Ulnar Sensory Nerve - Recording the little finger (antidromic)
Origin:  C8 root, lower trunk and lateral cord of the brachial plexus, ulnar nerveRecording Site:  Little fingerReference Site:  Little fingerGround:  Palm or top of handStimulation Site:  Wrist Procedure:  The recording electrode is placed on the proximal phalange of the little finger...
 
Dorsal Ulnar Sensory Nerve (antidromic)
Origin:  C8 root, lower trunk and medial cord of the brachial plexusRecording Site:  Top of handReference Site:  Base of 5th fingerGround:  Top of HandStimulation Site:  WristProcedure:  The recording electrode is placed on the dorsum of the hand at...
 
Radial Sensory Nerve (antidromic)
Origin:  C6-C7 roots, upper or middle trunk and posterior cord of the brachial plexus, radial nerveRecording Site:  Base of the FDI web space between the index finger and thumbReference Site:  Base of thumbGround:  Palm or top of handStimulation Site: ...
 
Median Sensory Nerve - Recording the ring finger (antidromic)
Origin:  C7 roots, middle trunk and lateral cord of the brachial plexus.Recording Site: Ring FingerReference Site:  Ring FingerGround:  Palm or top of handStimulation Site:  Wrist Procedure:  The recording electrode is placed on the proximal phalanx of the ring finger...
 
Ulnar Sensory Nerve - Recording the ring finger (antidromic)
Origin:  C8 root, lower trunk and lateral cord of the brachial plexus.Recording Site:  Ring fingerReference Site:  Ring fingerGround:  Palm or top of handStimulation Site:  WristProcedure:  The recording electrode is placed on the proximal phalange of the fourth finger...
 
Median Palmar Mixed Nerve (orthodromic)
Recording Site:  Wrist over median nerve (bar electrode)Reference Site:  Wrist over median nerve (bar electrode)Ground:  Top of handStimulation Site:  Palm, between the 2nd and 3rd metacarpal bones.Procedure:  The recording and reference electrodes (bar...
 
Ulnar Palmar Mixed Nerve (orthodromic)
Recording Site:  Wrist over the ulnar nerve (bar electrode)Reference Site:  Wrist over the ulnar nerve (bar electrode)Ground:  Top of handStimulation Site:  Palm, between the 4th and 5th metacarpal bones.Procedure:  The recording and reference electrodes...
 
Lateral Antebrachial Cutaneous Sensory Nerve (antidromic)
Origin:  C6 root, upper trunk and lateral cord of the brachial plexus,       Musculocutaneous nerveRecording Site:  Forearm (bar electrode)Reference Site:  Forearm (bar electrode)Ground:  ForearmStimulation Site:  ElbowProcedure:  The recording and...
 
Medial Antebrachial Cutaneous Sensory Nerve - Forearm (antidromic)
Origin:  C8-T1 root, lower trunk and medial cord of the brachial plexusRecording Site:  Forearm (bar electrode)Reference Site:  Forearm (bar electrode)Ground:  ForearmStimulation Site:  ElbowProcedure:  The recording and reference electrodes (bar electrode)...
 
Sensory Nerves
Lateral Antebrachial CutaneousLateral Antebrachial Cutaneous Sensory Nerve - Forearm(antidromic) Lateral Femoral Cutaneous Lateral Femoral Cutaneous Sensory Nerve – recording the lateral thigh (antidromic)Medial Antebrachia; Cutaneous Medial Antebrachial...
 
Lower Extremity Nerve Conductions
SensoryLateral Femoral Cutaneous Sensory Nerve – recording the lateral thigh (antidromic)Saphenous Sensory Nerve – recording anterior to the Medial Malleolus (antidromic)Superficial Peroneal Sensory Nerve - recording anterior to the Lateral Malleolus (antidromic) ...
 
All Nerves
A list of all nerves commonly tested in alphabetic order.Axillary Axillary Motor Nerve - recording the DeltoidBlink Blink Reflexes – recording the Orbicularis OculiF-waves F-WavesFacial Facial Motor Nerve – recording the Orbicularis OculiFemoralFemoral...
 
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...
 
Ulnar Motor Nerve - Recording the First Dorsal Interosseous (FDI)
Origin:  C8-T1 roots, lower trunk and medial cord of the brachial plexus, ulnar nerveRecording Site:  First Dorsal Interosseous (FDI or 1st DI)Reference Site:  Base of thumbGround:  Palm or Top of HandStimulation Site:  Wrist, below elbow and above elbow...
 
Median and Ulnar motor nerves- Recording the 2nd Lumbrical and interossei
Origin:    Median – C8-T1 roots, lower trunk and medial cord of the brachial plexus, median nerve.Ulnar – C8-T1 roots, lower trunk and medial cord of the brachial plexus, ulnar nerve.Recording Site:  Palm, between the 2nd and 3rd metacarpal bones.Reference...
 
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...
 
Musculocutaneous Motor Nerve - recording the Biceps
Upper ExtremityLower Extremity Motor NervesSensory Nerves All NervesSpecial Studies
 
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. ...
 
Sural Sensory Nerve - recording behind the Lateral Malleolus (antidromic)
Sural Sensory Nerve (antidromic)Origin:  S1 root, sacral plexus, sciatic nerve, tibial nerve.Recording Site:  Lateral MalleolusReference Site:  Side of the footGround:  Top of footStimulation Site:  Back of lower legProcedure:  The patient should be...
 
Superficial Peroneal Sensory Nerve - recording anterior to the Lateral Malleolus (antidromic)
Origin:  L5 root, sacral plexus, sciatic nerve, peroneal nerve.Recording Site:  Lateral lower leg (bar electrode)Reference Site:  Lateral lower leg (bar electrode)Ground:  Medial lower legStimulation:  Lateral lower legProcedure:  The recording and reference...
 
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...
 
Lateral Femoral Cutaneous Sensory Nerve - recording the lateral thigh (antidromic)
Origin:  L2-3 roots, lumbar plexusRecording Site:  Anterolateral thigh (bar electrode)Reference Site:  Thigh (bar electrode)Ground Site:  ThighStimulation Site:  Iliac crestProcedure:  The recording and reference electrodes (bar electrode) is placed 12cm down from the iliac crest...
 
Medial and Lateral Plantar Mixed Nerves (orthodromic)
Medial and Lateral Plantar Mixed Nerves (orthodromic)Origin:  S1 root, sacral plexus, sciatic nerve, tibial nerveRecording Site:  Ankle (bar electrode)Reference Site:  Ankle (bar electrode)Ground:  Top of footStimulation Site:               ...
 
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...
 
Blink Reflexes – recording the Orbicularis Oculi
Origin:  Brainstem nuclei, facial nerves, trigeminal nervesRecording Site:  Orbicularis OculiReference Site:  Lateral orbit or side of noseGround:  ForeheadStimulation Site:  Supraorbital notchProcedure:  The recording electrode is placed over the orbicularis oculi...
 
F-Waves
The most common routine F-wave responses are recorded from the Median (APB), Ulnar (ADM), Peroneal (EDB) and the Tibial (AH) motor nerves.  However, F-waves can be recorded from any motor nerve.  F-waves vary in amplitude and latency and may not be recorded following every stimulation...
 
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...
 
Normal Value Disclaimer
Please be awere that each lab may have its own normal values. These can vary based upon age, temperature, technique and equipment.Age generally leads to a lower amplitude and a prolonged distal latency.  Temperature has significant effects on nerve conduction studies...
 
Axillary Motor Nerve - Anatomy (image)

 
Brachial Plexus (image)

 
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...
 
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...
 
Sciatic Nerve
abductor digiti quinti pedis - Tibial Divisionabductor hallucis brevis - Tibial Divisionbiceps femoris - long head - Tibial Divisionbiceps femoris - short head - Peroneal Divisionextensor digitorum brevis - Peroneal Divisionextensor digitorum longus - Peroneal...
 
Tibial Nerve
abductor digiti quinti pedisabductor hallucis brevisflexor digitorum longusflexor hallucis brevis gastrocnemius - lateral headgastrocnemius - medial head soleustibialis posterior
 
Lateral Plantar Nerve
abductor digiti quinti pedis
 
Superficial Peroneal Nerve
peroneus longus
 
Deep Peroneal Nerve
extensor digitorum brevisextensor digitorum longus extensor hallucis longustibialis anterior
 
Common Peroneal Nerve
extensor digitorum brevisextensor digitorum longusextensor hallucis longus peroneus longustibialis anterior
 
Femoral Nerve
iliopsoasiliopsoasvastus lateralis vastus medialis 
 
Inferior Gluteal Nerve
gluteus maximus
 
Superior Gluteal Nerve
gluteus mediustensor fasciae latae
 
Medial Plantar Nerve
abductor hallucis brevisflexor hallucis brevis
 
Obturator Nerve
adductor 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:  
 
L2
adductor longusiliopsoas vastus lateralis vastus medialis
 
L3
adductor longusiliopsoas vastus lateralisvastus medialis
 
L4
adductor longus extensor hallucis longus gluteus medius iliopsoasiliopsoas semimembranosus semitendonosus tibialis anterior vastus lateralis vastus medialis tensor fasciae latae
 
L5
biceps femoris - long head biceps femoris - short head extensor hallucis longusflexor digitorum longus gastrocnemius - lateral head gluteus mediusgluteus maximus peroneus longus semimembranosussemitendonosus tibialis anteriortibialis posterior tensor fasciae latae  
 
S2
abductor digiti quinti pedisabductor hallucis brevisgastrocnemius - lateral headgastrocnemius - medial head gluteus maximussoleus
 
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:  
 
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:  
 
Lumbosacral Plexus

 
Lumbar Plexus

 
Sciatic Nerve (Peroneal Division)

 
Sciatic Nerve (Tibial Division)

 
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...
 
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...
 
Latissimus Dorsi (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:  ...
 
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: ...
 
Lateral Femoral Cutaneous Sensory Nerve - recording the lateral thigh (antidromic)
Origin:  L2-3 roots, lumbar plexusRecording Site:  Anterolateral thigh (bar electrode)Reference Site:  Thigh (bar electrode)Ground Site:  ThighStimulation Site:  Iliac crestProcedure:  The recording and reference electrodes (bar electrode) is placed 12cm down from the iliac crest...
 
Brachial Plexus (image)

 
Axillary Motor Nerve - Anatomy (image)

 
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...
 
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...
 
All Nerves
A list of all nerves commonly tested in alphabetic order.Axillary Axillary Motor Nerve - recording the DeltoidBlink Blink Reflexes – recording the Orbicularis OculiF-waves F-WavesFacial Facial Motor Nerve – recording the Orbicularis OculiFemoralFemoral...
 
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...
 
Sensory Nerves
Lateral Antebrachial CutaneousLateral Antebrachial Cutaneous Sensory Nerve - Forearm(antidromic) Lateral Femoral Cutaneous Lateral Femoral Cutaneous Sensory Nerve – recording the lateral thigh (antidromic)Medial Antebrachia; Cutaneous Medial Antebrachial...
 
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...
 
Nerve Conduction Studies
All Nerves   Upper Extremity Nerve Conduction Studies Lower Extremity Nerve Conductions  Motor Nerve Conduction Studies Sensory Nerves  Special Studies      These are studies not performed on a regular basis, including facial motor responses, repetitive...
 
Special Studies
Blink Blink Reflexes – recording the Orbicularis OculiF-waves F-WavesFacial Facial Motor Nerve – recording the Orbicularis OculiH-ReflexH-Reflex - recording the SoleusRepetitive Stimulation Repetitive Nerve Stimulation for Myasthenia Gravis (post-synaptic...
 
Upper Extremity Nerve Conduction Studies
MotorAxillary Motor Nerve - recording the Deltoid  Median and Ulnar motor nerves- Recording the 2nd Lumbrical and interossei Median Motor Study - Recording the Abductor Pollicis Brevis Musculocutaneous Motor Nerve - recording the Biceps  Radial Motor Nerve...
 
Lower Extremity Nerve Conductions
SensoryLateral Femoral Cutaneous Sensory Nerve – recording the lateral thigh (antidromic)Saphenous Sensory Nerve – recording anterior to the Medial Malleolus (antidromic)Superficial Peroneal Sensory Nerve - recording anterior to the Lateral Malleolus (antidromic) ...
 
Motor Nerve Conduction Studies
Axillary Axillary Motor Nerve - recording the DeltoidFacial Facial Motor Nerve – recording the Orbicularis OculiFemoralFemoral Motor Nerve - recording the Rectus FemorisMedian Median Palmar Mixed Nerve (orthodromic) Median Motor Study - Recording the Abductor...
 
Median Sensory Nerve - Recording the middle finger (antidromic)
Median Sensory Nerve - middle (antidromic)Origin:  C7 root, middle trunk and lateral cord of the brachial plexus, median nerveRecording Site:  Middle fingerReference Site:  Middle fingerGround:  Palm or top of handStimulation Site:  WristProcedure: ...
 
Median Sensory Nerve - Recording the thumb (antidromic)
Origin:  C6-C7 root, upper and middle trunk and lateral cord of the brachial plexus, median nerve.Recording Site:  ThumbReference Site:  ThumbGround:  Palm or top of handStimulation Site:  WristProcedure:  The recording electrode is placed on the proximal phalanx of the thumb...
 
Ulnar Sensory Nerve - Recording the little finger (antidromic)
Origin:  C8 root, lower trunk and lateral cord of the brachial plexus, ulnar nerveRecording Site:  Little fingerReference Site:  Little fingerGround:  Palm or top of handStimulation Site:  Wrist Procedure:  The recording electrode is placed on the proximal phalange of the little finger...
 
Normal Value Disclaimer
Please be awere that each lab may have its own normal values. These can vary based upon age, temperature, technique and equipment.Age generally leads to a lower amplitude and a prolonged distal latency.  Temperature has significant effects on nerve conduction studies...
 
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...
 
F-Waves
The most common routine F-wave responses are recorded from the Median (APB), Ulnar (ADM), Peroneal (EDB) and the Tibial (AH) motor nerves.  However, F-waves can be recorded from any motor nerve.  F-waves vary in amplitude and latency and may not be recorded following every stimulation...
 
Blink Reflexes – recording the Orbicularis Oculi
Origin:  Brainstem nuclei, facial nerves, trigeminal nervesRecording Site:  Orbicularis OculiReference Site:  Lateral orbit or side of noseGround:  ForeheadStimulation Site:  Supraorbital notchProcedure:  The recording electrode is placed over the orbicularis oculi...
 
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: ...
 
Medial and Lateral Plantar Mixed Nerves (orthodromic)
Medial and Lateral Plantar Mixed Nerves (orthodromic)Origin:  S1 root, sacral plexus, sciatic nerve, tibial nerveRecording Site:  Ankle (bar electrode)Reference Site:  Ankle (bar electrode)Ground:  Top of footStimulation Site:               ...
 
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...
 
Superficial Peroneal Sensory Nerve - recording anterior to the Lateral Malleolus (antidromic)
Origin:  L5 root, sacral plexus, sciatic nerve, peroneal nerve.Recording Site:  Lateral lower leg (bar electrode)Reference Site:  Lateral lower leg (bar electrode)Ground:  Medial lower legStimulation:  Lateral lower legProcedure:  The recording and reference...
 
Sural Sensory Nerve - recording behind the Lateral Malleolus (antidromic)
Sural Sensory Nerve (antidromic)Origin:  S1 root, sacral plexus, sciatic nerve, tibial nerve.Recording Site:  Lateral MalleolusReference Site:  Side of the footGround:  Top of footStimulation Site:  Back of lower legProcedure:  The patient should be...
 
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...
 
Musculocutaneous Motor Nerve - recording the Biceps
Upper ExtremityLower Extremity Motor NervesSensory Nerves All NervesSpecial Studies
 
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...
 
Median and Ulnar motor nerves- Recording the 2nd Lumbrical and interossei
Origin:    Median – C8-T1 roots, lower trunk and medial cord of the brachial plexus, median nerve.Ulnar – C8-T1 roots, lower trunk and medial cord of the brachial plexus, ulnar nerve.Recording Site:  Palm, between the 2nd and 3rd metacarpal bones.Reference...
 
Ulnar Motor Nerve - Recording the First Dorsal Interosseous (FDI)
Origin:  C8-T1 roots, lower trunk and medial cord of the brachial plexus, ulnar nerveRecording Site:  First Dorsal Interosseous (FDI or 1st DI)Reference Site:  Base of thumbGround:  Palm or Top of HandStimulation Site:  Wrist, below elbow and above elbow...
 
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 
 
Medial Antebrachial Cutaneous Sensory Nerve - Forearm (antidromic)
Origin:  C8-T1 root, lower trunk and medial cord of the brachial plexusRecording Site:  Forearm (bar electrode)Reference Site:  Forearm (bar electrode)Ground:  ForearmStimulation Site:  ElbowProcedure:  The recording and reference electrodes (bar electrode)...
 
Ulnar Sensory Nerve - Recording the ring finger (antidromic)
Origin:  C8 root, lower trunk and lateral cord of the brachial plexus.Recording Site:  Ring fingerReference Site:  Ring fingerGround:  Palm or top of handStimulation Site:  WristProcedure:  The recording electrode is placed on the proximal phalange of the fourth finger...
 
Median Sensory Nerve - Recording the ring finger (antidromic)
Origin:  C7 roots, middle trunk and lateral cord of the brachial plexus.Recording Site: Ring FingerReference Site:  Ring FingerGround:  Palm or top of handStimulation Site:  Wrist Procedure:  The recording electrode is placed on the proximal phalanx of the ring finger...
 
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...
 
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...
 
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 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 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...
 
Middle Deltoid EMG Technique (video)

 
Lateral Antebrachial Cutaneous Sensory Nerve (antidromic)
Origin:  C6 root, upper trunk and lateral cord of the brachial plexus,       Musculocutaneous nerveRecording Site:  Forearm (bar electrode)Reference Site:  Forearm (bar electrode)Ground:  ForearmStimulation Site:  ElbowProcedure:  The recording and...
 
Ulnar Palmar Mixed Nerve (orthodromic)
Recording Site:  Wrist over the ulnar nerve (bar electrode)Reference Site:  Wrist over the ulnar nerve (bar electrode)Ground:  Top of handStimulation Site:  Palm, between the 4th and 5th metacarpal bones.Procedure:  The recording and reference electrodes...
 
Median Palmar Mixed Nerve (orthodromic)
Recording Site:  Wrist over median nerve (bar electrode)Reference Site:  Wrist over median nerve (bar electrode)Ground:  Top of handStimulation Site:  Palm, between the 2nd and 3rd metacarpal bones.Procedure:  The recording and reference electrodes (bar...
 
Radial Sensory Nerve (antidromic)
Origin:  C6-C7 roots, upper or middle trunk and posterior cord of the brachial plexus, radial nerveRecording Site:  Base of the FDI web space between the index finger and thumbReference Site:  Base of thumbGround:  Palm or top of handStimulation Site: ...
 
Dorsal Ulnar Sensory Nerve (antidromic)
Origin:  C8 root, lower trunk and medial cord of the brachial plexusRecording Site:  Top of handReference Site:  Base of 5th fingerGround:  Top of HandStimulation Site:  WristProcedure:  The recording electrode is placed on the dorsum of the hand at...
 
Extensor Pollicis Longus EMG Technique (video)

 
Extensor Pollicis Brevis EMG Technique (video)

 
Extensor Carpi Radialis Longus EMG Technique (video)

 
Supinator EMG Technique (video)

 
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...
 
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: ...
 
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.
 
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)

 
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...
 
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
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...
 
Extensor Digitorum (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
 
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 Carpi Ulnaris (image)

 
Flexor Carpi Radialis (image)

 
Flexor Pollicis Longus EMG Technique (video)

 
Extensor Indicis Proprius EMG Technique (video)

 
Abductor Digiti Minimi EMG Technique (video)

 
First Dorsal Interosseous in Action with arrow (image)

 
Abductor Digiti Minimi Surface View with arrow (image)

 
First Dorsal Interosseous Needle Placement (image)

 
First Dorsal Interosseous EMG Technique (video)

 
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:
 
C3
Spinal Root: C3Muscles Innervated:
 
Abductor Pollicis Brevis - EMG Demo (video)

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

 
EMG Tutorial
Sandbox. Edit to your hear'ts content.
 
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...
 



Gallery Images



First Dorsal Interosseous in Act

 
Abductor Digiti Minimi Surface V

 
First Dorsal Interosseous Needle

 
Insertion point for EMG study of