Clinical Policy Title: Electrodiagnostic Studies: Electromyography and Nerve Conduction Studies

Clinical Policy Title: Electrodiagnostic Studies: Electromyography and Nerve Conduction Studies Clinical Policy Number: 09.01.04 Effective Date: June 1 st, 2014 Initial Review Date: Jan. 15th, 2014 Most Recent Review Date: Jan. 21, 2015 Next Review Date: January, 2016 RELATED POLICIES: NONE Policy contains: Needle electromyography (NEMG). Surface electromyography (SEMG). Nerve conduction study. Nc-stat System. NK Pressure Specified Sensory Device. Quantitative Sensory Testing. NeuroQuick, Neuropad. ABOUT THIS POLICY: AmeriHealth VIP Care has developed clinical policies to assist with making coverage determinations. AmeriHealth VIP Care clinical policies are based on guidelines from established industry sources, such as the Centers for Medicare & Medicaid Services (CMS), state regulatory agencies, the American Medical Association (AMA), medical specialty professional societies, and peer-reviewed professional literature. These clinical policies along with other sources, such as plan benefits and state and federal laws and regulatory requirements, including any state- or plan-specific definition of medically necessary, and the specific facts of the particular situation are considered by AmeriHealth VIP Care when making coverage determinations. In the event of conflict between this clinical policy and plan benefits and/or state or federal laws and/or regulatory requirements, the plan benefits and/or state and federal laws and/or regulatory requirements shall control. AmeriHealth VIP Care clinical policies are for informational purposes only and not intended as medical advice or to direct treatment. Physicians and other health care providers are solely responsible for the treatment decisions for their patients. AmeriHealth VIP Care clinical policies are reflective of evidence-based medicine at the time of review. As medical science evolves, AmeriHealth VIP Care will update its clinical policies as necessary. AmeriHealth VIP Care clinical policies are not guarantees of payment. Coverage Policy A. AmeriHealth VIP Care considers the use of Nerve Conduction Studies (NCS) when paired with Needle Electromyography (NEMG) to be clinically proven and therefore, medically necessary when the following criteria are met: a.) Performed by a properly trained individual in the fields of neurology, physiatry, or other individual who has specific training and expertise in electrophysiologic studies. b.) Consideration of appropriate diagnosis as listed by the American Association of Neuromuscular and Electrodiagnostic Medicine (attached). B. AmeriHealth VIP Care considers the use of the below listed electrodiagnostic tools be investigational and therefore, not medically necessary. a.) When a Nerve Conduction Study is performed in the absence of a Needle Electromyogram b.) When the diagnoses listed by the American Association of Neuromuscular and Electrodiagnostic Medicine are not included on the claim. c.) When non-standard diagnostic modalities such as surface EMG, the Nc-stat System, Quantitative Sensory Testing for lower extremity peripheral neuropathy, NeuroQuick, Neuropad, or NK Pressure Specified Sensory Device are employed. 1

Limitations: All other uses of electrodiagnostic modalities of Electromyography or Nerve Conductions Studies are not medically necessary. Alternative Covered Services: Needle inserted electromyograms and needle near-placed nerve conduction velocity tests. Imaging studies, doctor office visits. Background Diagnosis of neuromuscular disorders is often difficult. Conditions impacting the peripheral nervous system, muscles, motor cells of the spinal cord, or the neuromuscular junctions may have similar presentations. The conditions within this spectrum may range from amyotrophic lateral sclerosis (ALS), carpal tunnel syndrome, multiple sclerosis, myasthenia gravis, myotonic, spinal muscular atrophy and other conditions. After performance of a history and physical examination, the evaluating professionals may further require other diagnostic modalities in the evaluation of neuromuscular disorders such as Nerve Conduction Studies, needle Electromyography (NEMG), Autonomic Reflex Testing, Cardiovascular Autonomic Testing, or Muscle and/or Nerve Biopsy. The commonly performed tests of electromyogram and nerve conduction velocity have been standards for decades. However both tests require the insertion of needles into the area which can be uncomfortable for many patients. Additionally, in most states, the insertion of needles can only be performed by physicians or others whose licenses include this activity within scope of practice. Newer technologies have been developed to use surface methods for assessing nerve and muscle performance in order for patient comfort and for the ability of providers not licensed to insert needles. Surface Electromyography (SEMG) Rather than insert needles, surface electrodes are placed on the skin overlying affected muscles. While being noninvasive, SEMG have the disadvantage of being more subject to muscle movement artifact and have lower signal resolution. Newer technologies can improve the amplitude; but studies have not demonstrated that SEMG is superior to or even equal to the diagnostic capabilities of NEMG. The Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology (AAN) reviewed the efficacy of SEMG in 2000, and has not updated its position since. At that time it concluded: 1. Based on Class II data, SEMG is considered unacceptable as a clinical tool in the diagnosis of neuromuscular disease at this time (Type E recommendation). 2. Based on Class III data and inconclusive or inadequate Class II data, SEMG is considered unacceptable as a clinical tool in the diagnosis of low back pain at this time (Type E recommendation). 3. Based on Class III data, SEMG is considered an acceptable tool for kinesiology analysis of movement disorders; for differentiating types of tremors, myoclonus, and dystonia; for evaluating gait and posture disturbances; and for evaluating psychophysical measures of reaction and movement time (Type C recommendation). Meekins, So and Quan wrote the review of SEMG for the American Association of Neuromuscular & Electrodiagnostic Medicine in 2008. Their meta-analysis of the literature subsequent to the AAN s position paper concluded that the technology was of possible assistance in diagnosis of neuromuscular diseases, fatigue associated with post-polio syndrome and electomechanical function in myotonic dystrophy. However all of these were a level C. There are insufficient data to support its utility for distinguishing between neuropathic and myopathic conditions or for the diagnosis of specific neuromuscular diseases. 2

The International Chiropractors Association (California) developed consensus based guidelines in 2009 and indicated that in the management of patients with a whiplash injury, that the use of SEMG may be helpful in the evaluation of cervical spine pain, trapezius pain and low back disorders. This guideline did not provide any strength of evidence statements but represented the opinion of the authors. Nerve Conduction Studies Nerve conduction studies, also termed nerve conduction velocity studies, are used in assessing the health of peripheral nerves. The study is performed by measuring the response of an electrical stimulation applied at a surface electrode. Sensory function is measured at another surface electrode placed over the skin in the area of distribution of the peripheral nerve in question. The motor responses are measured by the muscle response as detected by an electrode over the muscle whose innervation is in question. Nerve conduction studies assess the speed (i.e. conduction velocity or latency), size or amplitude, and shape of the patient s response to the electrical stimulation. Common Symptoms and Diagnosis Symptoms Generalized weakness Facial weakness (including ptosis) Facial pain and/or numbness Involuntary facial movement Dysphagia Dysarthria Respiratory insufficiency Neck pain Diagnoses Neuropathies Myopathies (including endocrine) Motor system disease (e.g., amyotrophic lateral sclerosis) Neuromuscular junction disorder (e.g., myasthenia gravis) Facial (seventh cranial) nerve lesions Myopathy Neuromuscular junction disorder (e.g., myasthenia gravis) Injury of the trigeminal (fifth cranial) nerve Myokymia Hemifacial spasm Myopathy Neuromuscular junction disorder (e.g., myasthenia gravis) Motor system disease (e.g., amyotrophic lateral sclerosis) Injury of the hypoglossal (twelfth cranial) nerve Neuromuscular junction disorder (e.g., myasthenia gravis) Motor system disease (e.g., amyotrophic lateral sclerosis) Phrenic nerve lesions Myopathy (e.g., acid maltese deficiency) 3

Thoracic pain Back pain Shoulder and arm pain, numbness, altered sensation (e.g., pins and needles), weakness, cramps, fasciculations, muscle atrophy or hypertrophy (focal or diffuse) Hip and leg pain, numbness, altered sensation (i.e., pins and needles), weakness, cramps, fasciculations, muscle atrophy or hypertrophy Urinary and anal sphincter dysfunction Distal weakness Proximal weakness Myasthenia gravis Motor system disease (e.g., amyotrophic lateral sclerosis) Cervical radiculopathy Brachial plexopathy Focal neuropathy (e.g., spinal accessory nerve) Thoracic radiculopathy Lumbosacral radiculopathy Lumbosacral plexopathy Cervical radiculopathy Brachial plexopathy Polyneuropathy Focal neuropathy (e.g., carpal tunnel syndrome, ulnar nerve injury at the elbow, suprascapular nerve injury at the shoulder) Myopathy Motor system disease (e.g., amyotrophic lateral sclerosis) Syrinx Lumbosacral radiculopathy Lumbosacral plexopathy Polyneuropathy Focal neuropathy (e.g., tarsal tunnel syndrome, femoral [focal or diffuse] mononeuropathy) Myopathy Motor system disease (e.g., amyotrophic lateral sclerosis) Lumbosacral radiculopathy Cauda equina syndrome Perineal neuropathy Lumbar stenosis Polyradiculopathy Pudendal nerve injury Diffuse lumbosacral root injury Polyneuropathy Focal mononeuropathy (e.g., carpal tunnel syndrome, ulnar neuropathy) Myopathy (e.g., inclusion body myositis, distal 4

myopathy) Myopathy Plexopathy From REFERRAL GUIDELINES FOR ELECTRODIAGNOSTIC MEDICINE CONSULTATIONS Approved by the American Association of Neuromuscular & Electrodiagnostic Medicine (formerly AAEM): August 1996. http://aanem.org/practice/position-statements.aspx (Last accessed Jan. 12, 2015) Several new technologies have entered the market over the past decade with a goal of making electrodiagnostics easier. These are machines that attempt to duplicate the results of Needle EMG and NCS but have not yet had sufficient studies to demonstrate in real world settings that they are equivalent. For this reason tests such as Quantitative Sensory Testing for Diagnosis of Lower Extremity Peripheral Neuropathy, Nc-stat System and NK Pressure Specified Sensory Device. Methods Searches: AmeriHealth VIP Care searched PubMed and the databases of: UK National Health Services Centre for Reviews and Dissemination. Agency for Healthcare Research and Quality s National Guideline Clearinghouse and other evidence-based practice centers. The Centers for Medicare & Medicaid Services. Searches were conducted on Jan. 5, 2014 using the terms Nerve Conduction Study and Electromyogram. We included: Systematic reviews, which pool results from multiple studies to achieve larger sample sizes and greater precision of effect estimation than in smaller primary studies. Systematic reviews use predetermined transparent methods to minimize bias, effectively treating the review as a scientific endeavor, and are thus rated highest in evidencegrading hierarchies. Guidelines based on systematic reviews. Economic analyses, such as cost-effectiveness, and benefit or utility studies (but not simple cost studies), reporting both costs and outcomes sometimes referred to as efficiency studies which also rank near the top of evidence hierarchies. Findings Electrodiagnostic testing is key to determining the cause of neuropathic and myopathic symptoms. The most widely studied tools are needle electromyography (NEMG) and nerve conduction studies used in tandem. Needle EMG activity assessed includes insertional activity, spontaneous activity, and voluntary motor-unit action potential. Through needle EMG there can be localization of the disorder, chronicity and whether the pathophysiology is neuropathic, myopathic or associated with a neuromuscular junction disorder (Preston, 2002). Standard Nerve Conduction Studies with specifically placed skin electrodes can ascertain amplitude, duration, area, latency, and conduction velocity. 5

Surface EMG is a new emerging technology but studies still fail to demonstrate superiority to needle EMG and the available studies are at a Level III, not meeting high level of confidence. Because of symptoms which may mimic other conditions, needle EMG and nerve conduction studies should be paired. Summary of Clinical Evidence Citation Meekins (AANEM) 2008 Drost (2006) Content, Methods, Recommendations Key Points Review of past guidelines and current literature to date of article.surface EMG (SEMG) measures myoelectrical signals recorded from sensors place on the skin surface, making this a potentially useful technology. Concluded that SEMG adds no clinical utility over needle EMG (NEMG) for diagnosis of neuromuscular disease. Additional data is at a level C, class III data) for distinguishing between neuropathic and myopathic conditions or for fatigue associated with post-polio syndrome. Key Points Review of 29 clinical studies and four reviews of High density-surface EMG. Studies show that there has been significant technical advancement in optimizing the HD SEMG techniques. In principle HD SEMG allows pathological changes at the muscle unit level to be detected especially for neurogenic disorders and channelopathies. The studies did not meet the level of evidence necessary for high level clinical evidence so the recommendations are for further development and implementation of HD SEMG as a clinical diagnostic tool. Rubin (2012) Key Points Wilbourn (2002) Paper is a review of the technical issues with electrodiagnostic studies of NCS and EMG. Potential technical problems encountered during the studies may interfere with accurate and reliable acquisition of information. These are discussed in this paper. Key Points Review of nerve conduction studies for neurologists. Important elements of a Nerve Conduction Study include amplitude, duration, area, latency, and conduction velocity. Nerve lesions cause axon loss or demyelination which have distinctive 6

NCS patterns. Role of nerve conduction studies and needle EMG is to localize nerve lesions as accurately as possible. Papanas (2011) Key Points Neuropathy needs to be diagnosed early to prevent complications such as neuropathic pain. New tests are classified into those assessing large-fiber function and small-fiber function. Emerging tests are promising but must be evaluated in prospective studies Cost-effectiveness needs more careful appraisal. Clinician should still rely on established modalities to diagnose neuropathy. Glossary Electrodiagnostic medicine According to the American Board of Electrodiagnostic Medicine, this is defined as Electrodiagnostic (EDX) medicine is the medical subspecialty that applies neurophysiologic techniques to diagnose, evaluate, and treat patients with impairments of the neurologic, neuromuscular, and/or muscular systems. Needle electromyogram (NEMG) Is an electromyogram performed with needle insertion into a muscle. An electromyogram records the muscle activity after electrical stimulation. Nerve conduction study Is a diagnostic test that measures the movement of an impulse through a nerve after electrical stimulation of the nerve. Surface electromyogram (SEMG)--Is an electromyogram performed surface stimulation and records from a muscle. An electromyogram records the muscle activity after electrical stimulation. Related Policies: AmeriHealth VIP Care Utilization Management program description. References Professional society guidelines/others: American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM). Proper performance and interpretation of electrodiagnostic studies. Muscle Nerve. 2006 Mar; 33(3):436-9. 7

American Association of Electrodiagnostic Medicine. AAEM position statements. Who is qualified to practice electrodiagnostic medicine? Muscle Nerve Suppl. 1999; 8:S263-5. Approved May, 1999, and reconfirmed May 2012 http://aanem.org/practice/position-statements.aspx (Last accessed Jan. 11 th, 2015) International Chiropractors Association of California. Management of whiplash associated disorders. Sacramento (CA): International Chiropractors Association of California; 2009. Jablecki CK, Andary MT, Floeter MK, Miller RG, Quartly CA, Vennix MJ, Wilson JR; American Association of Electrodiagnostic Medicine; American Academy of Neurology; American Academy of Physical Medicine and Rehabilitation. Practice parameter: Electrodiagnostic studies in carpal tunnel syndrome. Report of the American Association of Electrodiagnostic Medicine, American Academy of Neurology, and the American Academy of Physical Medicine and Rehabilitation. Neurology. 2002 Jun 11; 58(11):1589-92 Keith MW, Masear V, Chung K, Maupin K, Andary M, Amadio PC, Barth RW, Watters WC 3rd, Goldberg MJ, Haralson RH 3rd, Turkelson CM, Wies JL. Diagnosis of carpal tunnel syndrome. J Am Acad Orthop Surg. 2009 Jun; 17(6):389-96. Meekins GD, So Y, Quan D. American Association of Neuromuscular & Electrodiagnostic Medicine evidenced-based review: use of surface electromyography in the diagnosis and study of neuromuscular disorders. Muscle Nerve. 2008 Oct; 38(4):1219-24. Pullman SL, Goodin DS, Marquinez AI, Tabbal S, Rubin M. Clinical utility of surface EMG: report of the therapeutics and technology assessment subcommittee of the American Academy of Neurology. Neurology. 2000 Jul 25; 55 (2):171-7. Peer-reviewed references: SEMG Criswell E, Cram's Introduction to Surface Electromyography, Second Edition, Jones and Bartlett Publishers, 40 Tall Pine Drive, Sudbury, Ma.01776 Drost G, Stegeman DF, van Engelen BG, Zwarts MJ. Clinical applications of high-density surface EMG: a systematic review. J Electromyogr Kinesiol. 2006 Dec; 16(6):586-602. Hogrel JY. Clinical applications of surface electromyography in neuromuscular disorders. Neurophysiol Clin. 2005 Jul; 35(2-3):59-71 Lahrmann H, Zifko U, Grisold W. Clinical utility of surface EMG: report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology. 2001 May 22; 56(10):1421 Preston DC, Shapiro BE. Needle electromyography. Fundamentals, normal and abnormal patterns. Neurol Clin. 2002 May; 20(2):361-96, vi. Rubin DI. Technical issues and potential complications of nerve conduction studies and needle electromyography. Neurol Clin. 2012 May; 30(2):685-710 8

Wimalaratna HS, Tooley MA, Churchill E, Preece AW, Morgan HM. Quantitative surface EMG in the diagnosis of neuromuscular disorders. Electromyogr Clin Neurophysiol. 2002 Apr-May; 42(3):167-74 Point of Care NCV Hayes, NK Pressure-Specified Sensory Device (Sensory Management Services LLC) for Tarsal Tunnel Syndrome Diagnosis, Oct. 10, 2006 Hayes, Nc-stat System (NeuroMetrix Inc.) for Noninvasive Nerve Conduction Testing of Upper Extremity Neuropathy, Feb 27, 2007 Hayes, Quantitative Sensory Testing for Diagnosis of Lower Extremity Peripheral Neuropathy, Nov. 25 th, 2013 Perkins BA, Grewal J, Ng E, Ngo M, Bril V. Validation of a novel point-of-care nerve conduction device for the detection of diabetic sensorimotor polyneuropathy. Diabetes Care. 2006 Sep; 29(9):2023-7. Papanas N, Ziegler D. New diagnostic tests for diabetic distal symmetric polyneuropathy. J Diabetes Complications. 2011 Jan-Feb; 25(1):44-51. Wilbourn AJ. Nerve conduction studies. Types, components, abnormalities, and value in localization. Neurol Clin. 2002 May; 20(2):305-38 Clinical Trials: Training for Diagnosing Neurological Disorders, NCT 00132353, National Institute of Neurological Disorders and Stroke (NINDS) http://clinicaltrials.gov/ct2/show/nct00132353?term=nerve+conduction+study&rank=16. Accessed January 12, 2015. Surface EMG Biofeedback for Children With Cerebral Palsy NCT01681888 University of Southern California http://clinicaltrials.gov/ct2/show/nct01681888?term=surface+emg&rank=3. Accessed January 12, 2015. Use of EMG to Assess Clinical Hypertonia NCT00472914 http://clinicaltrials.gov/ct2/show/nct00472914?term=surface+emg&rank=5. Accessed January 12, 2015. Centers for Medicare and Medicaid Services (CMS) National Coverage Determination National Coverage Determination (NCD) for Sensory Nerve Conduction Threshold Tests (sncts) (160.23) http://www.cms.gov/medicare-coverage-database/details/ncddetails.aspx?ncdid=270&ncdver=2&docid=160.23+&bc=gaaaaagaaaaaaa%3d%3d& ( Accessed January 12, 2015. Local Coverage Determinations Local Coverage Determination (LCD): Nerve Conduction Studies and Electromyography (L31346) -, Iowa, Kansas, Missouri - Entire State, Nebraska,, Alaska, Alabama,Arkansas, Arizona, Connecticut, Florida, Georgia, Idaho, Illinois, Indiana, Kentucky, Louisiana, Massachusetts, Maine, Michigan, Minnesota, Missouri -Entire State Mississippi, Montana, North Carolina, North Dakota, Nebraska, New Hampshire, New Jersey, Ohio, Oregon, Rhode Island, South Carolina, South Dakota, Tennessee, Utah, Virginia, Virgin Islands, Vermont, Washington, Wisconsin, West Virginia, Wyoming. 9

_http://www.cms.gov/medicare-coverage-database/details/lcddetails.aspx?lcdid=31346&contrid=143&ver=30&contrver=1&searchtype=advanced&coverageselection= Local&ArticleType=SAD%7cEd&PolicyType=Both&s=All&KeyWord=Nerve+Conduction+Studies+and+Electro myography&keywordlookup=doc&keywordsearchtype=exact&kq=true&bc=iaaaabaaaaaaaa%3d%3d &. Accessed January 12, 2015. Commonly Submitted Codes Below are the most commonly submitted codes for the service(s)/item(s) subject to this policy. This is not an exhaustive list of codes. Providers are expected to consult the appropriate coding manuals and bill in accordance with those manuals. CPT Code 95860 95861 95863 95864 95867 95868 95870 95872 95885 95886 95887 95905 Description Needle electromyography; 1 extremity with or without related paraspinal areas. And subsequent codes related to electromyography. 2 extremities with or without related paraspinal areas. 3 extremities with or without related paraspinal areas 4 extremities with or without related paraspinal areas cranial nerve supplied muscle(s), unilateral cranial nerve supplied muscle(s), bilateral limited study of muscles in 1 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. complete, five or more muscles studied, innervated by three or more nerves or four or more spinal levels. Needle electromyography, non-extremity (cranial nerve supplied or axial) muscle(s) done with nerve conduction, amplitutde and latency/velocity study. Motor and/or sensory nerve conduction, using preconfigured electrode array(s), amplitude and latency/velocity study, each limb, includes F-wave study when performed, with interpretation and report. Comment Add-on code Add-on code Add-on code Frequently used in point of care studies 95907 Nerve conduction studies; 1-2 studies. 95908 Nerve conduction studies, 3-4 studies. 95909 Nerve conduction studies, 5-6 studies. 95910 Nerve conduction studies, 7-8 studies. 95911 Nerve conduction studies, 9-10. 95912 Nerve conduction studies, 11-12. 10

95913 95999 Nerve conduction studies, 13 or more studies. Unlisted neurological or neuromuscular diagnostic procedure. ICD-9 Code Description Comment 780.79 Generalized weakness 781.94 Facial weakness including ptosis (374.30-374.30) 784.0 Facial pain 350.2 Atypical facial pain 351.8 Facial nerve pain 782.0 Facial numbness 781.0 Involuntary facial movement 789.59 Dysphagia 784.51 Dysarthria 786.09 723.1 724.1 Respiratory insufficiency Neck pain Thoracic pain 724.4 Thoracic pain with radicular and visceral pain 518.82 Acute respiratory insufficiency 724.2, 724.5 Back pain 719.41 Shoulder pain 729.5 Arm pain 782.0 Numbness, altered sensation 728.87 Weakness 729.82 Cramps 11

781.0 Fasciculations 728.2, 356.1 Muscle atrophy 728.9, 728.87 Muscle hypertrophy 719.45 Hip pain 729.5 596.59 564.9 728.87 350 357 (plus appropriate 4 th digit) 359.0-359.9 259.8, 259.9 335.20 358.00, 358.01 351.9 951.2 351.8 351.8 951.7 354.8 271.0 723.4 353.0 355.9 724.2 353.1 356-357.9 Leg pain Urinary sphincter dysfunction Anal sphincter dysfunction Distal or proximal weakness Neuropathies Myopathies Endocrine myopathies Amyotrophic lateral sclerosis Myasthenia gravis Facial (seventh cranial) nerve lesions Injury of the trigeminal (fifth cranial) nerve Myokymia Hemifacial spasm Injury of the hypoglossal (twelfth cranial) nerve Phrenic nerve lesions Acid maltese deficiency Cervical radiculopathy Brachial plexopathy Focal neuropathy ( spinal accessory nerve) Lumbosacral/thoracic radiculopathy Lumbosacral plexopathy Polyneuropathy 12

957.1 955.7 336.0 354.-355.9 344.60 355.3 724.02 357.0 957.1 953.8 350-357.9 354.0 354.2 359.71 359.1 359.0-359.9 353.0-353.9 Nerve injury at the elbow Suprascapular nerve injury at the shoulder Syrinx Mononeuropathy Cauda equina syndrome Perineal neuropathy Lumbar stenosis Polyradiculopathy Pudendal nerve injury Diffuse lumbosacral root injury Polyneuropathy Carpal tunnel syndrome Ulnar neuropathy Inclusion body myositis Distal myopathy Myopathy Plexopathy ICD-10 Code Comment HCPCS Level II G0255 S3900 Description Current perception threshold/sensory nerve conduction test (SNCT), per limb, any nerve [when specified as other portable automated nerve conduction testing] Surface electromyography Not covered Comment 13