Asset Publisher


print Print Back Back

Neuromuscular and Electrodiagnostic Testing (EDX):  Nerve Conduction Studies (NCS) and Electromyography (EMG) Studies

Policy Number: MP-228

Latest Review Date: July 2023

Category: Medicine                                                                    


Nerve conduction velocity (NCV) studies may be considered medically necessary when conducted and interpreted at the same time as a needle electromyography (NEMG) test for ANY of the following indications:

  • Localization of focal neuropathies or compressive lesions/syndrome, including but not limited to any of the following:
    • Carpal tunnel,
    • Cubital tunnel syndrome,
    • Tarsal tunnel syndrome,
    • Peroneal nerve compression,
    • Thoracic outlet syndrome
  • Diagnosis and prognosis of traumatic nerve lesions or other nerve trauma;
  • Diagnosis or confirmation of suspected generalized neuropathies, including but not limited to ANY of the following:
  • Metabolic and nutritional (diabetic, uremic, amyloidosis, hypothyroidism, immune, vitamin B12 or thiamine deficiency),
  • Toxic neuropathy (e.g., vincristine, amiodarone),
  • Hereditary polyneuropathy (e.g., Charcot-Marie Tooth disease),
  • Infectious neuropathy (e.g., HIV, Lyme disease, Leprosy),
  • Demyelinating neuropathy (e.g., Guillain-Barre syndrome),
  • Idiopathic peripheral neuropathy;
  • Motor neuron conditions (e.g., amyotrophic lateral sclerosis [ALS or Lou Gehrig’s disease]):
    • Up to 4 motor nerves and 2 sensory nerves may be studied,
    • Needle EMG of up to 4 extremities (or limbs and facial or tongue muscles) is often necessary to document widespread denervation and to exclude a myopathy. 
    • One repetitive motor nerve stimulation study may be indicated to exclude a disorder affecting neuromuscular transmission;
  • Diagnosis of neuromuscular junction disorders (e.g., myasthenia gravis/myasthenic syndrome) or other neuromuscular conditions (e.g., fasciculation [muscle twitching]) using repetitive nerve stimulation:
    • Repetitive NCSs should be performed in at least 2 nerves and SFEMG in up to 2 muscles,
    • If any of the above tests are abnormal, up to 2 motor and 2 sensory NCSs may be performed to exclude neuropathies that can be associated with abnormal neuromuscular transmission;
    • At least 1 motor and 1 sensory NCS should be performed in a clinically involved limb, preferable in the distribution of a nerve studied with repetitive stimulation or SFEMG;
    • At least 1 distal and 1 proximal muscle should be studied by a needle EMG examination;
      • At least 1 of the muscles should be clinically involved and both muscles should be in clinically involved limbs;
  • Differential diagnosis of symptom-based complaints suggesting nerve root, peripheral nerve, muscle, or neuromuscular junction involvement, when pre-test evaluations are inconclusive and clinical assessment supports the need for the study, such as for any of the following:
  • Muscle weakness,
  • Muscle atrophy,
  • Muscle fasciculation,
  • Myokymia,
  • Myotonia,
  • Loss of dexterity,
  • Spasticity,
  • Hyper-reflexia,
  • Sensory deficits,
  • Diplopia,
  • Ptosis,
  • Swallowing dysfunction,
  • Dysarthria,
  • Impaired bowel motility,
  • Follow-up treatment of diabetic peripheral neuropathy, tested once every 24 months;
  • Disorders of peripheral nervous system;
  • Radiculopathy:
    • H reflexes and F waves may be necessary to support a diagnosis of root dysfunction.
    • Minimal evaluation includes 1 motor and 1 sensor NCS and a needle EMG examination of the involved limb.
      • Testing can include up to 3 motor NCSs (in cases of an abnormal motor NCS, the same nerve in the contralateral limb and another motor nerve in the ipsilateral limb can be studied) and 2 sensory NCSs,
      • Bilateral studies are often necessary to exclude a central disc herniation with bilateral radiculopathies or spinal stenosis or to differentiate between radiculopathy and plexopathy, polyneuropathy, or mononeuropathy.
    • To differentiate brachial plexopathy from cervical radiculopathy, all major sensory and motor nerves (radial, median, ulnar, and medial and lateral antebrachial cutaneous sensory; radial, median ulnar and possibly axillary and musculocutaneous motor) and a needle EMG examination in both upper extremities may need to be studied.
    • To differentiate lumbosacral radiculopathy from lumbar plexopathy, it may be necessary to study all major sensory and motor nerves (superficial peroneal and sural sensory; peroneal and posterior tibial motor) and perform a needle EMG examination in both lower extremities;
  • Myopathy:
    • A needle EMG examination of 2 limbs is indicated.
    • To exclude polyneuropathy or neuronopathy, 2 motor and 2 sensory NCSs are indicated.
    • To exclude a disorder of neuromuscular transmission, 2 repetitive motor nerve stimulation studies may be needed;
  • Myositis,
  • Nerve root compression,
  • Neuritis,
  • Plexopathy,
  • Spinal cord injury;
  • Polyneuropathy/mononeuropathy multiplex:
    • To distinguish the nature of the polyneuropathy (axonal or demyelinating, diffuse or multifocal) it may be necessary to study 4 motor and 4 sensory nerves, consisting of 2 motor and 2 sensory NCS in 1 leg, 1 motor and 1 sensory NCS in the opposite leg and 1 motor and 1 NCS in 1 arm.
    • At least 2 limbs should be studied by a needle EMG.

Nerve conduction velocity (NCV) studies when performed alone may be considered medically necessary for ANY of the above indications, in ANY of the following clinical presentations:

  • As a follow-up study of a neuromuscular structure that has undergone previous electrodiagnostic evaluation,
  • Current use of an anticoagulant,
  • Presence of lymphedema,
  • Carpal tunnel syndrome (unilateral, bilateral) ;
    • For patients with suspected carpal tunnel syndrome (CTS), the following recommendations were made and endorsed by the American Academy of Neurology (AAN), the American Academy of Physical Medicine and Rehabilitation, and the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM):
      • Perform a median sensory NCS across the wrist with a conduction distance of 13 to 14 cm.  If the result is abnormal, do a comparison of the result of the median sensory NCS to the result of a sensory NCS of one other adjacent sensory nerve in the symptomatic limb.
        • If the initial median sensory NCS across the wrist has a conduction distance > 8 cm and the result is normal, do one of the following additional studies:
        • Comparison of median sensory or mixed nerve conduction across the wrist over a short (7-8 cm) conduction distance with ulnar sensory nerve conduction across the wrist over the same short (7-8 cm) conduction distance; OR
        • Comparison of median sensory conduction across the wrist with radial or ulnar sensory conduction across the wrist in the same limb; OR
      • Comparison of median sensory or mixed nerve conduction through the carpal tunnel to sensory or mixed NCS of proximal (forearm) or distal (digit) segments of the median nerve in the same limb.
      • Motor conduction studies of the median nerve recording from the muscle and of one other nerve in the symptomatic limb to include measurement of distal latency.
      • NCS may be done pre-op a maximum number of times as listed in the Table 1 chart.  NSC may be indicated one time post op, to provide reassessment concerning possible failure of surgery
    •  Post-surgical repair of CTS, to assess possible failure of treatment, tested one time.

Nerve conduction studies (NCS) are considered not medically necessary for the following indications:

  • The F-wave study for carpal tunnel syndrome.
  • NCS as screening tests for polyneuropathy of diabetes or end-stage renal disease.
  • NCS for the sole purpose of monitoring disease intensity or treatment effectiveness for polyneuropathy of diabetes or end-stage renal disease.
  • NCS using portable automated point-of-care hand-held devices. Examples of these nerve conduction testing devices include, but are not limited to, NC-Stat by NeuroMetrix®, Neurometer® and Brevio® NCS-Monitor.  See Policy #304 for additional information regarding Automated Point-of-Care Nerve Conduction Tests.
  • NCS done by mobile neurodiagnostic labs.
  • NCS done by technicians alone, not under direct supervision of a trained eligible provider.
    • Direct supervision in the office setting means the eligible provider must be present in the office suite and immediately available and able to provide assistance and direction throughout the time the service is performed. Direct supervision does not mean that the eligible provider must be present in the same room with his or her aide.
  • NCS performed without needle EMG at the same time is considered not medically necessary except the limited clinical situations listed above.

Neuromuscular Junction Testing

Neuromuscular junction testing may be considered medically necessary for ANY of the following indications:

  • Myopathy,
  • Motor neuropathy (e.g., ALS),
  • Botulinum toxicity,
  • Myasthenia Gravis,
  • Lambert Eaton myasthenic syndrome;
  • The presence of ANY of the following:
    • Diplopia,
    • Dysphagia,
    • Fatigue/weakness that progresses with repetitive activity;

Neuromuscular Junction testing is considered not medically necessary for ANY other indication.

Frequency of Testing

Services performed for excessive frequency are considered not medically necessary.  Frequency is considered excessive when services are performed more frequently than generally accepted by AANEM.

The AANEM lists these recommendations concerning a reasonable maximum number of NCV studies per diagnostic category needed for a physician to render a diagnosis:

Table 1: Recommended Maximum Number of Electrodiagnostic Studies for Specific Diagnoses

Maximum Number of Studies


Needle Electromyography

Nerve Conduction Studies

Other Electromyographic Studies




Number of Services (Tests)

Motor NCS

with and/or

without F wave







Junction Testing

(Repetitive Stimulation)

Carpal Tunnel (unilateral)






Carpal Tunnel (bilateral)


















Polyneuropathy/ Mononeuropathy Multiplex












Motor Neuronopathy (e.g., ALS)












Neuromuscular Junction






Tarsal Tunnel Syndrome (unilateral)






Tarsal Tunnel Syndrome (bilateral)






Weakness, Fatigue, Cramps, or Twitching (focal)






Weakness, Fatigue, Cramps, or Twitching (general)






Pain, Numbness, or Tingling (unilateral)






Pain, Numbness, or Tingling (bilateral)






Adapted from American Association of Electrodiagnostic Medicine (1999).EMG: electromyography; NCS: nerve conduction studies study; RNS: repetitive nerve stimulation.

These limits will not apply if the patient requires evaluation by more than one EDX consultant (i.e., a second opinion or an expert opinion at a tertiary care center) in a given year or if the patient requires evaluation for a second diagnosis in a given year. 

Surface EMG testing is considered not medically necessary.

See Policy #066 Quantitative Sensory Testing (QST)

See Policy #304 Automated Point-of-Care Nerve Conduction Tests

See Policy #306 Intraoperative Neurophysiologic Monitoring

See Policy #362 Paraspinal Surface Electromyography (SEMG) to Evaluate and Monitor Back Pain


Electromyography (EMG) and nerve conduction studies (NCS), also collectively known as an electrodiagnostic assessment, are intended to evaluate the electrical functioning of muscles and peripheral nerves. These tests are used as diagnostic aids for the evaluation of myopathy and peripheral neuropathy by identifying, localizing, and characterizing electrical abnormalities in the skeletal muscles and peripheral nerves.

The NCS is performed by an eligible provider (e.g., physician, physical therapist or chiropractor) or by a trained allied health professional under direct supervision of an eligible provider trained in electrodiagnostic medicine. The American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) states, “NCSs should be either (a) performed directly by physician or (b) performed by a trained individual under the direct supervision of a physician. Direct supervision means that the physician is in close physical proximity to the EDX laboratory while testing is underway, is immediately available to provide the trained individual with assistance and direction, and is responsible for selecting the appropriate NCSs to be performed”.

Electrodiagnostic Assessment

Electromyography (EMG) and nerve conduction study (NCS) have been used for several decades as adjuncts to the clinical examination in the evaluation of myopathy and peripheral neuropathy. The intent of these tests is to evaluate the integrity and electrical function of muscles and peripheral nerves. They are performed when there is a clinical suspicion for a myopathic or neuropathic process and when clinical examination and standard laboratory testing is unable to make a definitive diagnosis.

Test results do not generally provide a specific diagnosis. Rather, they provide additional information that assists physicians in characterizing a clinical syndrome. EMG/NCS may be useful when there is no clear etiology when symptoms are severe or rapidly progressing, or when symptoms are atypical (e.g., asymmetrical, acute onset, or appearing to be autonomic).

According to the American Association of Neuromuscular and Electrodiagnostic Medicine, electrodiagnostic assessment has the following goals:

  • Identify normal and abnormal nerve, muscle, motor or sensory neuron, and neuromuscular junction (NMJ) functioning
  • Localize region(s) of abnormal function
  • Define the type of abnormal function
  • Determine the distribution of abnormalities
  • Determine the severity of abnormalities
  • Estimate the date of a specific nerve injury
  • Estimate the duration of the disease
  • Determine the progression of abnormalities or of recovery from abnormal function
  • Aid in diagnosis and prognosis of disease
  • Aid in selecting treatment options
  • Aid in following response to treatment by providing objective evidence of change in NM function
  • Localize correct locations for injections of intramuscular agents

Components of the electrodiagnostic exam may include needle EMG, NCS, repetitive nerve stimulation study, somatosensory evoked potentials, and blink reflexes.


Needle EMG

An EMG needle electrode is inserted into selected muscles, chosen by the examining physician depending on the differential diagnosis and other information available at the time of exam. The response of the muscle to electrical stimulation is recorded. There are three components evaluated: observation at rest, action potential with minimal voluntary contraction, and action potential with maximum contraction.

Single Fiber EMG

In this technique, a needle electrode records the response of a single muscle fiber. This test can evaluate “jitter,” which is defined as the variability in time between activation of the nerve and generation of the muscle action potential. Single fiber EMG can also be used to measure fiber density, which is defined as the mean number of muscle fibers for 1 motor unit.

Nerve Conduction Studies

Both motor and sensory nerve conduction are assessed. For motor conduction, electrical stimuli are delivered along various points on the nerve and the electrical response is recorded from the appropriate muscle. For sensory conduction, electrical stimuli are delivered to one point on the nerve and the response recorded at a distal point on the nerve. Parameters recorded include velocity, amplitude, latency, and configuration.

Late Wave Responses

Late waves are a complement to the basic NCS study and evaluate the functioning of the proximal segment of peripheral nerves, such as the nerve root and the anterior horn cells. There are two types of late responses, the H-reflex and the F wave.

The H-reflex is elicited by stimulating the posterior tibial nerve and measuring the response in the gastrocnemius muscle. It is analogous to the ankle reflex and can be prolonged by a radiculopathy at S1 or by a peripheral neuropathy.

The F wave is assessed by supramaximal stimulation of the distal nerve and can be used to estimate the conduction velocity in the proximal portion of the nerve. This will provide information on the presence of proximal nerve abnormalities, such as radiculopathy or plexopathy.

Repetitive Nerve Stimulation

Repetitive nerve stimulation studies are intended to evaluate the integrity and function of the NMJ. The test involves stimulating a nerve repetitively at variable rates and recording the response of the corresponding muscle(s). Disorders of the NMJ will show a diminished muscular response to repetitive stimulation.

Somatosensory Evoked Potentials

Somatosensory evoked potentials evaluate nerve conduction in various sensory fibers of both the peripheral and central nervous system and are used to test the integrity and function of these nerve pathways. They are typically used to assess nerve conduction in the spinal cord and other central pathways that cannot be assessed by standard NCS.

Blink Reflexes

The blink reflexes, which are analogs of the corneal reflex, are evaluated by stimulating the orbicularis oculi muscle at the lower eyelid. They are used to localize lesions in the fifth or seventh cranial nerves.

Differential Diagnosis

The specific components of an individual test are not standardized. Rather, a differential diagnosis is developed by the treating physician, and/or the clinician performing the test, and the specific components of the exam are determined by the disorders that are being considered in the differential. In addition, the differential diagnosis may be modified during the exam to reflect initial findings, and this may also influence the specific components that are included in the final analysis.


The most recent literature review was performed through April 13, 2023.

Summary of Evidence

For individuals with suspected peripheral neuropathy or myopathy who receive electrodiagnostic assessment including electromyography (EMG) and nerve conduction studies (NCS), the evidence includes small observational studies on a few diagnoses, such as carpal tunnel syndrome (CTS), radiculopathy, and myopathy. Relevant outcomes are test accuracy, symptoms, functional outcomes, and quality of life. Because electrodiagnostic assessment is considered the criterion standard for evaluating the electrical function of peripheral nerves and muscles, there is no true alternative reference standard against which the sensitivity and specificity of particular EMG/NCS abnormalities for particular clinical disorders can be calculated. Different studies have used different reference standards, such as EMG/NCS measures of healthy individuals or clinical examination results. In general, these tests are considered more specific than sensitive and normal results do not rule out the disease. The limited evidence has shown a wide range of sensitivities, which are often less than 50%. The specificity is expected to be considerably higher, but the data are insufficient to provide precise estimates of either sensitivity or specificity. The evidence is insufficient to determine that the technology results in an improvement in the health net outcome.

Practice Guidelines and Position Statements

American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM)

The American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) has published several position statements on recommended coverage policy for electromyography (EMG) and nerve conduction studies (NCS). The first, initially published in 1999, was updated in 2004. The second was published in 2017. Needle EMG and NCS testing was recommended for the following indications:

  • Focal neuropathies, entrapment neuropathies, or compressive lesions/syndromes such as carpal tunnel syndrome, ulnar neuropathies, or root lesions, for localization.
  • Traumatic nerve lesions, for diagnosis and prognosis.
  • Diagnosis or confirmation of suspected generalized neuropathies, such as diabetic, uremic, metabolic, or immune.
  • Repetitive nerve stimulation in diagnosis of neuromuscular junction disorders such as myasthenia gravis, myasthenic syndrome.
  • Symptom-based presentations such as “pain in limb,” weakness, disturbance in skin sensation or “paresthesia” when appropriate pretest evaluations are inconclusive and the clinical assessment unequivocally supports the need for the study.
  • Radiculopathy-cervical, lumbosacral.
  • Polyneuropathy-metabolic, degenerative, hereditary.
  • Plexopathy-idiopathic, trauma, infiltration.
  • Myopathy-including polymyositis and dermatomyositis, myotonic, and congenital myopathies.
  • Precise muscle location for injections such as botulinum toxin, phenol, etc.

This document also listed situations that were considered investigational.

AANEM published practice parameters on the utility of EMG/NCS for the diagnosis of peroneal neuropathy in 2005. This evidence-based review focused on whether EMG/NCS are useful in diagnosing peroneal neuropathy and/or in determining prognosis. Table 2 lists recommendations AANEM deemed “possibly useful, to make or confirm” a diagnosis.

Table 2. Guidelines on Diagnosis of Peroneal Neuropathy




Motor NCSs of the peroneal nerve recording from the AT and EDB muscles



Orthodromic and antidromic superficial peroneal sensory NCS



At least one additional normal motor and sensory NCS in the same limb, to assure that the peroneal neuropathy is isolated, and not part of a more widespread local or systemic neuropathy



Data are insufficient to determine the role of needle EMG in making the diagnosis of peroneal neuropathy

However, abnormalities on needle examination outside of the distribution of the peroneal nerve should suggest alternative diagnoses




In patients with confirmed peroneal neuropathy, EDX studies are possibly useful in providing prognostic information, with regards to recovery of function



AT: anterior tibialis; COE: class of evidence; EDB: extensor digitorum brevis; EDX: electrodiagnostic; EMG: electromyography; LOR: level of recommendation; NCS: nerve conduction studies.

A 2003 consensus statement on diagnosing multifocal motor neuropathy from AANEM has stated:

“Multifocal motor neuropathy is a diagnosis that is based on recognition of a characteristic pattern of clinical symptoms, clinical signs, and electrodiagnostic findings. The fundamental electrodiagnostic finding is partial conduction block of motor axons.”

A 2004 AANEM approved a position statement, endorsed by the American Academy of Neurology and the American Academy of Physical Medicine & Rehabilitation, on diagnostic electromyography included the following:

  • “Clinical needle electromyography (EMG) is an invasive medical procedure during which the physician inserts an electrode into a patient's muscles to diagnose the cause of muscle weakness. Needle EMG allows physicians to distinguish a wide range of conditions, from carpal tunnel syndrome to ALS (Lou Gehrig disease).
  • Needle EMG is also an integral component of the neurological examination that cannot be separated from the physician’s evaluation of the patient. The test is dynamic and depends upon the visual, tactile, and audio observations of the examiner. There is no way for physicians to independently verify the accuracy of reports performed by non-physicians.
  • Misdiagnosis can mean delayed or inappropriate treatment (including surgery) and diminished quality of life. Because needle EMG is strictly diagnostic, the procedure clearly and exclusively falls within the practice of medicine.”

AANEM (2018) published a policy statement on the use of EMG for distal symmetric polyneuropathy. The statement described five situations in which EMG would be beneficial for patients with distal symmetric polyneuropathy: “1) determining primary and alternative diagnoses; 2) determining severity, duration, and prognosis of disease; 3) evaluating risk of associated problems; 4) determining the effect of medications; and 5) evaluating the effect of toxic exposures.”

The AANEM (2020) issued a consensus statement on the utility and practice of electrodiagnostic (EDX) testing in the pediatric population. The following conclusions were made:

  • "…certain categories of inherited diseases such as muscular dystrophy and SMA [spinal muscular atrophy] do not routinely require EMG as part of the diagnostic evaluation. However, in atypical cases EDX testing can provide critical assistance with narrowing of the differential diagnosis."
  • "…techniques and practice for this important diagnostic test modality will continue to evolve in the future."
  • "EDX testing in children will continue to complement other diagnostic test modalities such as serum tests, muscle biopsy, imaging, and genetic testing."

American Academy of Orthopaedic Surgeons

The American Academy of Orthopaedic Surgeons (2007) issued guidelines on the diagnosis of carpel tunnel syndrome. Table 3 lists recommendations made.

Table 3. Guidelines on Diagnosis of Carpal Tunnel Syndrome






“The physician may obtain electrodiagnostic tests to differentiate among diagnoses.”




“The physician may obtain electrodiagnostic tests in the presence of thenar atrophy and/or persistent numbness.”




“The physician should obtain electrodiagnostic tests if clinical and/or provocative tests are positive and surgical management is being considered.”




“If the physician orders electrodiagnostic tests, the testing protocol should follow the AAN/AANEM/AAPMR guidelines for diagnosis of CTS.”



AANEM: American Association of Neuromuscular & Electrodiagnostic Medicine; AAN: American Academy of Neurology; AAPM&R: American Academy of Physical Medicine and Rehabilitation; CTS: carpal tunnel syndrome; GOE: grade of evidence; LOR: level of recommendation (II/III: “fair evidence”; IV/V: “poor quality evidence; V: “expert consensus”).

AAOS issued guidelines on the management of carpal tunnel syndrome in 2016. Table 4 lists recommendations made.

Table 4. Guidelines on Management of Carpal Tunnel Syndrome


Strength of


"Limited evidence supports that a hand-held nerve conduction study (NCS) device might be used for the diagnostic of carpal

tunnel syndrome."


"Moderate evidence supports that diagnostic questionnaires and/or electrodiagnostic studies could be used to aid the

diagnosis of carpal tunnel syndrome."


North American Spine Society

The North American Spine Society published guidelines on the diagnosis and treatment of lumbar disc herniation in 2012. This document made the following statement about the use of EMG/NCS for diagnosis of lumbar disc herniation:

“Electromyography, nerve conduction studies and F-waves are suggested to have limited utility in the diagnosis of lumbar disc herniation with radiculopathy. H-reflexes can be helpful in the diagnosis of an S1 radiculopathy, though are not specific to the diagnosis of lumbar disc herniation. (Grade of Recommendation: B)”

U.S. Preventive Services Task Force Recommendations

Not applicable.


Electrodiagnostic medicine, nerve conduction studies (NCS), nerve conduction velocity studies, motor nerve conduction studies, sensory nerve conduction studies, mixed nerve conduction studies, needle electromyography (EMG), late responses, H-reflex studies, F-wave studies single-fiber electromyography (SFEMG), NC-stat System, NC-Stat by NeuroMetrix®, Neurometer® and Brevio® NCS-Monitor., EPAD™, CERSR® Electromyography System Physical Monitoring Registration Unit-S (PMRU-S), MyoVision 3G Wirefree™ System NuVasive® NV M5 System, Neuro Omega™ System, CareFusion Nicolet® EDX, EPAD 2™, Mediracer® NCS, Mega-TMS™


Electromyography (EMG) and nerve conduction study (NCS) measure nerve and muscle function and may be indicated when evaluating limb pain, weakness related to possible spinal nerve compression or other neurologic injury or disorder. There are a number of electromyographic devices that have received marketing clearance by the U.S. Food and Drug Administration (FDA). Several devices are listed in Table 5.

Table 5. Electromyographic Devices Approved by FDA



FDA Clearance

510 (k) No.

FDA Product Code


SafeOp Surgical




CERSR® Electromyography System





Physical Monitoring Registration Unit-S (PMRU-S)





MyoVision 3G Wirefree™ System

Precision Biometrics




NuVasive® NV M5 System





Neuro Omega™ System

Alpha Omega Engineering




CareFusion Nicolet® EDX

CareFusion 209




Sierra Summit, Sierra Scent

Cadwell Industries





SafeOp Surgical




Mediracer® NCS











Soterix Medical, Inc.








Coverage is subject to member’s specific benefits.  Group-specific policy will supersede this policy when applicable.

ITS: Home Policy provisions apply

FEP: Special benefit consideration may apply.  Refer to member’s benefit plan. 


According to 2022 CPT® instructions:

“Waveforms must be reviewed on site in real time, and the technique (stimulus site, recording site, ground site, filter settings) must be adjusted, as appropriate, as the test proceeds in order to minimize artifact, and to minimize the chance of unintended stimulation of adjacent nerves and the unintended recording from adjacent muscles or nerves.  Reports must be prepared on site by the examiner, and consist of the work product of the interpretation of numerous test results, using well-established techniques to assess the amplitude, latency, and configuration of waveforms elicited by stimulation at each site of each nerve tested.  This includes the calculation of nerve conduction velocities, sometimes including specialized F-wave indices, along with comparison to normal values, summarization of clinical and electrodiagnostic data, and physician or other qualified health care professional interpretation.” 

The following definitions apply for billing codes 95905-95913:

The use of the term “onsite” indicates that the summary of the patient’s history and physical examination, execution of all of the appropriate nerve conduction studies and EMG examinations, analysis of the EDX data, and determination of the diagnoses for the patient are all performed in the same location which is most commonly the EDX laboratory. “Onsite” would preclude the use of telemetry or other technologies to allow the EDX data to be transmitted and interpreted at a location different from where the EDX study is performed.

The use of the term “real time” with regard to nerve conduction studies indicates that information from the history and physical examinations are integrated*, the specific and tailored EDX study is performed, and the analysis of the waveforms are all done at the same time and while the patient is present in the EDX laboratory (whether that be in an office, a hospital, or a medical clinic). An EDX study performed in “real time” is more sensitive and accurate since it allows the specific NCS and EMG tests performed to be modified as dictated by the results as they arise and it allows the physician to perform additional NCS or EMG studies, if necessary, after preliminary review and before the patient leaves the EDX laboratory.

*Integration in the context of EDX studies describes how attributes of the history and physical examinations are used to design a specific grouping of nerve conduction studies and a specific selection of muscles to be evaluated during the needle EMG examination for each patient.  The EDX examination is therefore tailored to each patient.

Codes 95907-95913 describe one or more nerve conduction studies. 

  • For the purposes of coding, a single conduction study is defined as a sensory conduction test, a motor conduction test with or without an F wave test, or an H-reflex test. 
  • Each type of study (sensory, motor with or without F wave, H-reflex) for each nerve includes all orthodromic and antidromic impulses associated with that nerve and constitutes a distinct study when determining the number of studies in each grouping (e.g., 1-2, or 3-4 nerve conduction studies). 
  • Each type of nerve conduction study is counted only once when multiple sites on the same nerve are stimulated or recorded.  The numbers of these separate tests should be added to determine which code to use.  

CPT codes:


Needle electromyography (EMG) studies of anal or urethral sphincter, any technique


Needle electromyography; one extremity, with or without related paraspinal areas


Needle electromyography; two extremities, with or without related paraspinal areas


Needle electromyography; three extremities, with or without related paraspinal areas


Needle electromyography; four extremities, with or without related paraspinal areas


Needle electromyography; larynx


Needle electromyography; hemidiaphragm


Needle electromyography; cranial nerve supplied muscle(s), unilateral


Needle electromyography; cranial nerve supplied muscles; bilateral


Needle electromyography; thoracic paraspinal muscles (excluding T1)


Needle electromyography; limited study of muscles in one extremity or non-limb (axial) muscles (unilateral or bilateral), other than thoracic paraspinal, cranial nerve supplied muscles, or sphincters


Needle electromyography using single fiber electrode, with quantitative measurement of jitter, blocking and/or fiber density, any/all sites of each muscle studied


Needle electromyography, each extremity, with related paraspinal     areas, when performed, done with nerve conduction, amplitude and latency/velocity study; limited (list separately in addition to code for primary procedure)


Needle electromyography, each extremity, with related paraspinal     areas, when performed, done with nerve conduction, amplitude and latency/velocity study ;complete, five or more muscles studied, innervated by three or more nerves or four or more spinal levels (list separately in addition to code for primary procedure)


Needle electromyography, non-extremity (cranial nerve supplied or axial) muscle(s) done with nerve conduction, amplitude and latency/velocity study (list separately in addition to code for primary procedure)


Nerve conduction studies; 1-2 studies


Nerve conduction studies; 3-4 studies


Nerve conduction studies; 5-6 studies


Nerve conduction studies; 7-8 studies


Nerve conduction studies; 9-10 studies


Nerve conduction studies; 11-12 studies


Nerve conduction studies; 13 or more studies


Neuromuscular junction testing (repetitive stimulation, paired stimuli), each nerve, and 1 method



Surface electromyography (EMG)



  1. AANEM policy statement on electrodiagnosis for distal symmetric polyneuropathy. Muscle Nerve. Feb 2018; 57(2): 337-339.
  2. American Association of Electrodiagnostic Medicine. Guidelines in electrodiagnostic medicine. Recommended policy for electrodiagnostic medicine. Muscle Nerve Suppl. 1999; 8:S91-105.
  3. American Academy of Neurology (AAN). Position Statement: diagnostic electromyography in the practice of medicine. 2004; 03173ecf8446/Recommended_Policy_EDX_Medicine_062810.pdf.
  4. American Academy of Orthopaedic Surgeons. Management of Carpal Tunnel Syndrome Evidence-Based Clinical Practice Guideline. February 29, 2016;
  5. AANEM policy statement on electrodiagnosis for distal symmetric polyneuropathy. Muscle Nerve. Feb 2018; 57(2):337-339.
  6. Chang MH, Liu LH, Lee YC, et al. Comparison of sensitivity of transcarpal median motor conduction velocity and conventional conduction techniques in electrodiagnosis of carpal tunnel syndrome. Clin Neurophysiol. May 2006; 117(5):984-991.
  7. Fowler JR, Munsch M, Tosti R, et al. Comparison of ultrasound and electrodiagnostic testing for diagnosis of carpal tunnel syndrome: study using a validated clinical tool as the reference standard. J Bone Joint Surg Am. Sep 3 2014; 96(17):e148.
  8. Ghosh PS, Sorenson EJ. Diagnostic yield of electromyography in children with myopathic disorders. Pediatr Neurol. Aug2014; 51(2): 215-9.
  9. Gooch CL, Weimer LH. The electrodiagnosis of neuropathy: basic principles and common pitfalls. Neurol Clin. Feb 2007; 25(1):1-28.
  10. Homan MM, Franzblau A, Werner RA, et al. Agreement between symptom surveys, physical examination procedures and electrodiagnostic findings for the carpal tunnel syndrome. Scand J Work Environ Health. Apr 1999; 25(2):115-124.
  11. IOM (Institute of Medicine). 2011. Clinical Practice Guidelines We Can Trust. Washington, DC: The National Academies Press.

  12. Kang PB, McMillan HJ, Kuntz NL, et al. Utility and practice of electrodiagnostic testing in the pediatric population: An AANEM consensus statement. Muscle Nerve. Feb 2020; 61(2): 143-155.
  13. Lee DH, Claussen GC, Oh S. Clinical nerve conduction and needle electromyography studies. J Am Acad Orthop Surg. Jul-Aug 2004; 12(4):276-287.
  14. Marciniak C, Armon C, Wilson J, et al. Practice parameter: utility of electrodiagnostic techniques in evaluating patients with suspected peroneal neuropathy: an evidence-based review. Muscle Nerve. Apr 2005; 31(4):520-527.
  15. Mondelli M, Aretini A, Arrigucci U, et al. Clinical findings and electrodiagnostic testing in 108 consecutive cases of lumbosacral radiculopathy due to herniated disc. Neurophysiol Clin. Oct 2013; 43(4):205-215.
  16. North American Spine Society (NASS) Evidence-Based Clinical Guidelines Committee. Evidence-Based Clinical Guidelines for Multidisciplinary Spine Care. 2012;
  17. Olney RK, Lewis RA, Putnam TD, et al. Consensus criteria for the diagnosis of multifocal motor neuropathy. Muscle Nerve. Jan 2003; 27(1):117-121. 
  18. Rabie M, Jossiphov J, Nevo Y. Electromyography (EMG) accuracy compared to muscle biopsy in childhood. J Child Neurol. Jul 2007; 22(7):803-808.
  19. Tulipan JE, Lutsky KF, Maltenfort MG, et al. Patient-reported disability measures do not correlate with electrodiagnostic severity in carpal tunnel syndrome. Plast Reconstr Surg Glob Open. Aug 2017; 5(8):e1440.


Medical Policy Group, June 2005 (2)

Medical Policy Group, November 2005 (2)

Medical Policy Administration Committee, November 2005

Available for comment December 1, 2005-January 14, 2006

Medical Policy Group, April 2007 (2)

Medical Policy Administration Committee, April 2007

Medical Policy Group, April 2008 (2)

Medical Policy Administration Committee, April 2008

Available for comment April 4-May 18, 2008

Medical Policy Group, April 2008 (2)

Medical Policy Administration Committee May 2008

Available for comment May 3-June 16, 2008

Medical Policy Group, June 2008 (2)

Medical Policy Administration Committee, July 2008

Available for comment June 17-July 31, 2008

Medical Policy Group, June 2009 (2)

Medical Policy Group, July 2009 (2)

Medical Policy Group, August 2009 (2)

Medical Policy Administration Committee, August 2009

Available for comment August 10-September 23, 2009

Medical Policy Group, January 2010 (2)

Medical Policy Administration Committee, January 2010

Available for comment January 26-March 11, 2010

Medical Policy Group, December 2011 (3): Added new 2012 Codes – 95885, 95886, 95887

Medical Policy Group, November 2012: Added new 2013 Codes 95907, 95908, 95909, 95910, 95911, 95912, & 95913 effective January 1, 2013; Deleted Codes 95900, 95903, 95904, 95934, & 95936 effective January 1, 2013.

Medical Policy Group, January 2013 (2): 2013 CPT® coding instructions added re: on site, real time review of wave forms  by the examiner and interpretation by qualified physician or other qualified health care professional added. 

Medical Policy Administration Committee, February 2013

Medical Policy Group, May 2014 (5):  Added policy statement for coverage of NCV and EMG concurrently and coverage of NCV alone; Also added coverage information for neuromuscular junction testing; Key Points, CPT Codes, and References updated to support Policy Statements.

Medical Policy Administration Committee, May 2014

Available for comment May 22 through July 5, 2014

Medical Policy Group, July 2014 (5): Updated Description, Policy statement, Key Points and References; Added information that Physical Therapist who are currently listed on the American Physical Therapy Association website as a Board Certified Clinical Electrophysiologic Certified Specialist per the ABPTS can perform electrodiagnostic studies; Added definition of “onsite” and “real-time” and reference to support, Also added under neuromuscular junction for at least two nerves to be tested.

Medical Policy Administration Committee, July 2014.

Available for comment July 12 through August 25, 2014

Medical Policy Group, September 2014 (5):  Updated Description and Policy Statement by removing physician and replacing with eligible provider (e.g., physician, physical therapist, or chiropractor); Removed specific information about physical therapist.  No change to policy statement.

Medical Policy Group, August 2015 (6):  Updates to Description, Key Points, Approved by Governing Bodies and References; no change to policy statement.

Medical Policy Panel, July 2017

Medical Policy Group, July 2017 (6): Updates to Description, Key Points, Governing Bodies, Key Words and Practice Guidelines. No change to policy statement.

Medical Policy Panel, June 2018

Medical Policy Group, July 2018 (6): Updates to Key Points, Governing Bodies, Practice Guidelines and References. No change to policy statement.

Medical Policy Panel, June 2019

Medical Policy Group, July 2019 (3): 2019 Updates to Key Points, Practice Guidelines and Position Statements, and References. No changes to policy statements or intent.

Medical Policy Panel, October 2020

Medical Policy Group, November 2020 (3): 2020 Updates to Key Points, Practice Guidelines and Position Statements, References and Key Words: added: EPAD 2™. No changes to policy statements or intent.

Medical Policy Panel, June 2021

Medical Policy Group, July 2021 (3): 2021 Updates to Key Points and References. No changes to policy statements or intent.

Medical Policy Panel, June 2022

Medical Policy Group, June 2022 (3): 2022 Updates to Key Points, Practice Guidelines and Position Statements, Approved by Governing Bodies, References, and Key Words: Mediracer® NCS, Mega-TMS™. No changes to policy statement or intent.

Medical Policy Panel, June 2023

Medical Policy Group, July 2023 (3): 2023 Updates to Description, Key Points, Practice Guidelines and Position Statements, Benefit Applications, and References. No changes to policy statement or intent.

This medical policy is not an authorization, certification, explanation of benefits, or a contract. Eligibility and benefits are determined on a case-by-case basis according to the terms of the member’s plan in effect as of the date services are rendered. All medical policies are based on (i) research of current medical literature and (ii) review of common medical practices in the treatment and diagnosis of disease as of the date hereof. Physicians and other providers are solely responsible for all aspects of medical care and treatment, including the type, quality, and levels of care and treatment.

This policy is intended to be used for adjudication of claims (including pre-admission certification, pre-determinations, and pre-procedure review) in Blue Cross and Blue Shield’s administration of plan contracts.

The plan does not approve or deny procedures, services, testing, or equipment for our members. Our decisions concern coverage only. The decision of whether or not to have a certain test, treatment or procedure is one made between the physician and his/her patient. The plan administers benefits based on the member’s contract and corporate medical policies. Physicians should always exercise their best medical judgment in providing the care they feel is most appropriate for their patients. Needed care should not be delayed or refused because of a coverage determination.

As a general rule, benefits are payable under health plans only in cases of medical necessity and only if services or supplies are not investigational, provided the customer group contracts have such coverage.

The following Association Technology Evaluation Criteria must be met for a service/supply to be considered for coverage:

1. The technology must have final approval from the appropriate government regulatory bodies;

2. The scientific evidence must permit conclusions concerning the effect of the technology on health outcomes;

3. The technology must improve the net health outcome;

4. The technology must be as beneficial as any established alternatives;

5. The improvement must be attainable outside the investigational setting.

Medical Necessity means that health care services (e.g., procedures, treatments, supplies, devices, equipment, facilities or drugs) that a physician, exercising prudent clinical judgment, would provide to a patient for the purpose of preventing, evaluating, diagnosing or treating an illness, injury or disease or its symptoms, and that are:

1. In accordance with generally accepted standards of medical practice; and

2. Clinically appropriate in terms of type, frequency, extent, site and duration and considered effective for the patient’s illness, injury or disease; and

3. Not primarily for the convenience of the patient, physician or other health care provider; and

4. Not more costly than an alternative service or sequence of services at least as likely to produce equivalent therapeutic or diagnostic results as to the diagnosis or treatment of that patient’s illness, injury or disease.