National Medical Policy

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1 National Medical Policy Subject: Nerve Conduction Studies Policy Number: NMP237 Effective Date*: September 2005 Updated: September 2015 This National Medical Policy is subject to the terms in the IMPORTANT NOTICE at the end of this document For Medicaid Plans: Please refer to the appropriate Medicaid Manuals for coverage guidelines prior to applying Health Net Medical Policies The Centers for Medicare & Medicaid Services (CMS) For Medicare Advantage members please refer to the following for coverage guidelines first: Use Source Reference/Website Link National Coverage Determination (NCD) National Coverage Manual Citation X Local Coverage Determination (LCD)* Nerve Conduction Studies (NCS) and Electromyography (EMG); Nervous System Studies - Autonomic Function: Article (Local)* X Other MLN Matters Number: MM3339. June 18, Updated April 5, 2013 NCD: Sensory Nerve Conduction Threshold Test: Education/Medicare-Learning-Network- MLN/MLNMattersArticles/downloads/MM3339.pdf CMS Manual System. Department of Health & Human Services (DHHS). Pub Medicare National Coverage Determinations. Transmittal : and- Guidance/Guidance/Transmittals/downloads/r10 ncd.pdf Nerve Conduction Studies Sep 15 1

2 None Use Health Net Policy Instructions Medicare NCDs and National Coverage Manuals apply to ALL Medicare members in ALL regions. Medicare LCDs and Articles apply to members in specific regions. To access your specific region, select the link provided under Reference/Website and follow the search instructions. Enter the topic and your specific state to find the coverage determinations for your region. *Note: Health Net must follow local coverage determinations (LCDs) of Medicare Administration Contractors (MACs) located outside their service area when those MACs have exclusive coverage of an item or service. (CMS Manual Chapter 4 Section 90.2) If more than one source is checked, you need to access all sources as, on occasion, an LCD or article contains additional coverage information than contained in the NCD or National Coverage Manual. If there is no NCD, National Coverage Manual or region specific LCD/Article, follow the Health Net Hierarchy of Medical Resources for guidance. Current Policy Statement Health Net, Inc. considers nerve conduction studies medically necessary for any of the following: 1. Focal neuropathies or compressive lesions such as carpal tunnel syndrome, ulnar neuropathies or root lesions, for localization. 2. Traumatic nerve lesions, for diagnosis and prognosis. 3. Diagnosis or confirmation of suspected generalized neuropathies, such as diabetic, uremic, metabolic or immune. 4. Repetitive nerve stimulation in diagnosis of neuromuscular junction disorders such as myasthenia gravis, myasthenic syndrome. 5. For differential diagnosis of symptom-based complaints (e.g., pain in limb, weakness, disturbance in skin sensation or paresthesia) provided the clinical assessment supports the need for a study. 6. Radiculopathy - cervical, lumbosacral. 7. Polyneuropathy - metabolic, degenerative, hereditary. 8. Plexopathy - idiopathic, trauma, infiltration. 9. Myopathy - including polymyositis and dermatomyositis, myotonic, and congenital myopathies. 10. Precise muscle location for injections such as botulinum toxin, phenol, etc. Nerve conduction studies have been found to be medically necessary for any of the following diseases or conditions: Nerve Conduction Studies Sep 15 2

3 Alcoholic neuropathy Carpal tunnel syndrome Chronic inflammatory polyneuropathy Diabetic neuropathy Disorders of peripheral nervous system Distal median nerve dysfunction Fasciculation Friedreich's ataxia Guillain-Barre syndrome Lambert-Eaton Syndrome Muscle weakness Myositis Nerve root compression Pain in limb Primary amyloid Sciatic nerve dysfunction Sensorimotor polyneuropathy Swelling and cramps Traumatic injury to a nerve Brachial plexopathy Charcot-Marie-Tooth disease (hereditary) Common peroneal nerve dysfunction Diphtheria Disturbance of skin sensation Femoral nerve dysfunction General paresis Joint pain Mononeuritis multiplex Myopathy Nerve effects of uremia Neuritis Plexopathy Radial nerve dysfunction Secondary systemic amyloid Spinal cord injury Tibial nerve dysfunction Ulnar nerve dysfunction Note: Nerve conduction velocity studies are essential in evaluating neuromuscular disorders. They are usually performed in conjunction with needle electromyography. In limited cases only, nerve conduction velocity studies may be done without needle electromyography, if the specific criterion noted below is met. Nerve Conduction Velocity Studies Health Net, Inc. considers the limited use of nerve conduction studies (NCS) or nerve conduction velocity studies (NCV) done alone as medically necessary, only in any of the following specific situations: Established diagnosis of carpal tunnel syndrome; or Current use of anticoagulants; or As a follow-up study of neuromuscular structures that have undergone previous electrodiagnostic evaluation; or Presence of lymphedema; or Contraindication to the needle electromyography (NEMG) procedure. Not Medically Necessary Health Net, Inc. considers any of the following not medically necessary: Nerve conduction velocity (NCV) studies performed without needle EMG, other than when performed for the specific indications noted above; or Automated or hand-held portable noninvasive nerve conduction devices (E.g., NC Stat device, Brevio NCS-Monitor) since the diagnostic ability and clinical use of this type of testing has not been determined. Nerve Conduction Studies Sep 15 3

4 Investigational Health Net, Inc. considers surface electromyography (EMG) as a diagnostic tool for the evaluation of patients with neuromuscular diseases and low back pain investigational. Codes Related To This Policy NOTE: The codes listed in this policy are for reference purposes only. Listing of a code in this policy does not imply that the service described by this code is a covered or noncovered health service. Coverage is determined by the benefit documents and medical necessity criteria. This list of codes may not be all inclusive. On October 1, 2015, the ICD-9 code sets used to report medical diagnoses and inpatient procedures will be replaced by ICD-10 code sets. Health Net National Medical Policies will now include the preliminary ICD-10 codes in preparation for this transition. Please note that these may not be the final versions of the codes and that will not be accepted for billing or payment purposes until the October 1, 2015 implementation date. ICD-9 Codes Botulism 037 Tetanus 138 Late effects of acute poliomyelitis Malignant neoplasm of cranial nerves Malignant neoplasm of spinal cord Malignant neoplasm of spinal meninges Malignant neoplasm of other specified sites of nervous system Secondary malignant neoplasm, brain, and spinal cord Secondary malignant neoplasm, other parts of nervous system Benign neoplasm of cranial nerve Benign neoplasm of spinal cord Benign neoplasm of spinal meninges Benign neoplasm of other sites of nervous system Neurofibromatosis Diabetes with neurological manifestations; type II [non-insulin dependent type] [NIDDM type] [adult-onset type] or unspecified type, not stated as uncontrolled type I [insulin dependent type] [IDDM] [juvenile type], not stated as uncontrolled type II [non-insulin dependent type] [NIDDM] [adult-onset type] or unspecified type, uncontrolled type I [insulin dependent type] [IDDM] [juvenile type], uncontrolled Other and unspecified manifestations of thiamine deficiency Deficiency of other vitamins Lipoprotein deficiencies Myoclonus Idiopathic torsion dystonia Nerve Conduction Studies Sep 15 4

5 333.7 Symptomatic torsion dystonia Blepharospasm Orofacial dyskinesia Spasmodic torticollis Organic writer s cramp Fragments of torsions dystonia, other Spinocerebellar disease Werdnig-Hoffmann disease Spinal muscular atrophy, unspecified Kugelberg-Welander disease Other spinal muscular atrophy Motor neuron disease Other anterior horn cell diseases Anterior horn cell disease, unspecified Other diseases of spinal cord Disorders of the autonomic nervous system (Includes: disorders of peripheral autonomic, sympathetic, parasympathetic, or vegetative system) 340 Multiple sclerosis Neuromyelitis optica Schilder's disease Other demyelinating diseases of central nervous system Demyelinating disease of central nervous system, unspecified Hemiplegia Infantile cerebral palsy Monoplegia Cauda equina syndrome; without mention of neurogenic bladder with neurogenic bladder Other specified paralytic syndromes, locked in state Other specified paralytic syndrome Paralysis, unspecified Trigeminal neuralgia Atypical face pain Other trigeminal nerve disorders Bell's palsy Geniculate ganglionitis Other facial nerve disorders Facial nerve disorder, unspecified Disorders of pneumogastric (10th) nerve Disorders of accessory (11th) nerve Disorders of hypoglossal (12th) nerve Multiple cranial nerve palsies Unspecified disorder of cranial nerves Nerve Conduction Studies Sep 15 5

6 353.0 Brachial plexus lesions Lumbosacral plexus lesions Cervical root lesions, not elsewhere classified Thoracic root lesions, not elsewhere classified Lumbosacral root lesions, not elsewhere classified Neuralgic amyotrophy Other nerve root and plexus disorders Unspecified nerve root and plexus disorder Mononeuritis of upper limb and mononeuritis multiplex Mononeuritis of lower limb and unspecified site Hereditary and idiopathic peripheral neuropathy Inflammatory and toxic neuropathy Myoneural disorders Myopathy, unspecified Strabismus and other disorders of binocular eye movements Orthostatic hypotension Paralysis of vocal cords or larynx Laryngeal spasm Achalasia and cardiospasm 585 Polyneuropathy in uremia Stress incontinence, female Peripheral neuritis in pregnancy Dermatomyositis Polymyositis Eosinophilia myalgia syndrome Cervical spondylosis without myelopathy Cervical spondylosis with myelopathy Thoracic spondylosis without myelopathy Lumbosacral spondylosis without myelopathy Spondylosis with myelopathy, thoracic region Spondylosis with myelopathy, lumbar region Other spondylopathies Displacement of cervical, thoracic, or lumbar intervertebral disc without myelopathy Displacement of intervertebral disc, site unspecified, without myelopathy Schmorl s nodes Degeneration of cervical intervertebral disc Degeneration of thoracic or thoracolumbar intervertebral disc Degeneration of lumbar or lumbosacral intervertebral disc Degeneration of intervertebral disc, site unspecified Nerve Conduction Studies Sep 15 6

7 Invertebral disc disorder with myelopathy Postlaminectomy syndrome Other and unspecified disc disorder, unspecified region Other specified disc disorder Spinal stenosis in cervical region Cervicalgia Brachial neuritis or radiculitis NOS Torticollis, unspecified Spinal stenosis, other than cervical Pain in thoracic spine Lumbago Sciatica Thoracic or lumbosacral neuritis or radiculitis, unspecified Backache, unspecified Compression of spinal nerve root 725 Polymyalgia rheumatica Infective myositis Muscular wasting and disuse atrophy, not elsewhere classified Spasm of muscle Myalgia and myositis, unspecified Neuralgia, neuritis, and radiculitis, unspecified Pain in limb Other musculoskeletal symptoms referable to limbs, cramps Wrist drop (acquired) Claw hand (acquired) Other acquired deformities of forearm, excluding fingers Acquired deformities of ankle and foot Other acquired deformities of ankle and foot Spina bifida without mention of hydrocephalus Diastematomyelia Other malaise and fatigue Abnormal involuntary movements Abnormality of gait, lack of coordination Transient paralysis of limb Tetany Disturbance of skin sensation Other disturbance, including spasmodic dysphonia Incontinence of feces Incomplete bladder emptying Incontinence of urine Abnormal electromyogram Fracture of vertebral column with spinal cord injury Injury to facial nerve Injury to other specified cranial nerve Nerve Conduction Studies Sep 15 7

8 Spinal cord injury without evidence of spinal bone injury, cervical Spinal cord injury without evidence of spinal bone injury, dorsal thoracic Lumbar spinal cord injury without spinal bone injury Sacral spinal cord injury without spinal bone injury Cauda equina spinal cord injury without spinal bone injury Multiple sites of spinal cord injury without spinal bone injury Unspecified site of spinal cord injury without spinal bone injury Injury to nerve roots and spinal plexus Injury to other nerve(s) of trunk, excluding shoulder and pelvic girdles Injury to peripheral nerve(s) of shoulder girdle and upper limb Injury to peripheral nerve(s) of pelvic girdle and lower limb Injury to other and unspecified nerves Electrocution and nonfatal effects of electric current ICD-10 Codes A05.1 Botulism food poisoning A35 Other tetanus B91 Sequelae of poliomyelitis C72.0- C72.9 Malignant neoplasm of spinal cord, cranial nerves and other parts of central nervous system C79.31 Secondary malignant neoplasm of brain C79.32 Secondary malignant neoplasm of cerebral meninges C79.49 Secondary malignant neoplasm of other parts of nervous system D32.0- D32.9 Benign neoplasm of meninges D33.3 Benign neoplasm of cranial nerves D33.4 Benign neoplasm of spinal cord D33.7 Benign neoplasm of other specified parts of central nervous system E10.40-E10.49 Type 1 diabetes mellitus with neurological complications E11.40-E11.49 Type 2 diabetes mellitus with neurological complications E51.8 Other manifestations of thiamine deficiency E51.9 Thiamine deficiency, unspecified E56.0-E56.9 Other vitamin deficiencies E78.6 Lipoprotein deficiency G11.0-G11.9 Hereditary ataxia G12.0 Infantile spinal muscular atrophy, type I [Werdnig-Hoffman] G12.1 Other inherited spinal muscular atrophy G12.20-G12.29 Motor neuron disease G12.8 Other spinal muscular atrophies and related syndromes G12.9 Spinal muscular atrophy, unspecified G14 Postpolio syndrome G24.1 Genetic torsion dystonia Nerve Conduction Studies Sep 15 8

9 G24.3 Spasmodic torticollis G24.4 Idiopathic orofacial dystonia G24.5 Blepharospasm G24.9 Dystonia, unspecified G25.3 Myoclonus G25.89 Other specified extrapyramidal and movement disorders G35 Multiple sclerosis G36.0 Neuromyelitis optica [Devic] G37.0 Diffuse sclerosis of central nervous system G37.5 Concentric sclerosis [Balo] of central nervous system G37.9 Demyelinating disease of central nervous system, unspecified G50.0-G50.9 Disorders of trigeminal nerve G51.0-G51.9 Facial nerve disorders G52.2 Disorders of vagus nerve G52.3 Disorders of hypoglossal nerve G52.7 Disorders of multiple cranial nerves G52.8 Disorders of other specified cranial nerves G52.9 Cranial nerve disorder, unspecified G54.0-G54.9 Nerve root and plexus disorders G56.00-G56.92 Mononeuropathies of upper limb G57.00-G57.92 Mononeuropathies of lower limb G60.0-G65.2 Polyneuropathies and other disorders of the peripheral nervous system G70.00-G73.9 Diseases of myoneural junction and muscle G80.0-G80.9 Cerebral palsy G81.00-G81.94 Hemiplegia and hemiparesis G83.0-G83.9 Other paralytic syndromes G90.01-G90.9 Disorders of autonomic nervous system G95.0-G95.9 Other and unspecified diseases of spinal cord H50.00-H50.9 Other strabismus H51.0-H51.9 Other disorders of binocular movement I95.1 Orthostatic hypotension J38.00-J38.02 Paralysis of vocal cords and larynx J38.5 Laryngeal spasm K22.0 Achalasia of cardia M M Wrist or foot drop (aquired) M M Acquired clawhand M21.6X1- M21.6X9 Other acquired deformities of foot M M Other specified acquired deformities of unspecified forearm M M Unspecified acquired deformity of lower leg M33.00-M33.99 Dermatopolymyositis M35.3 Polymyalgia rheumatica M35.8 Other specified systemic involvement of connective tissue M47.01-M47.9 Spondylosis M50.00-M50.93 Cervical Disc disorders M51.04-M51.9 Thoracic, thoracolumbar, and lumbosacral intervertebral disc disorders M53.0-M53.9 Other and unspecified dorsopathies, not elsewhere classified M54.10 Radiculopathy, site unspecified M Infective myositis, unspecified site M60.9 Myositis, unspecified M62.40 Contracture of muscle, unspecified site Nerve Conduction Studies Sep 15 9

10 M62.50 Muscle wasting and atrophy, not elsewhere classified, unspecified site M Other muscle spasm M79.1 Myalgia M79.2 Neuralgia and neuritis, unspecified M Pain in unspecified limb M79.7 Fibromyalgia N18.9 Chronic Kidney disease, unspecified N39.3 Stress incontinence (female) (male) N39.41 Urge incontinence N39.42 Incontinence without sensory awareness N39.43 Post-void dribbling N39.44 Nocturnal enuresis N39.45 Continuous leakage N39.46 Mixed incontinence N Overflow incontinence N Other specified urinary incontinence Q05.5 Cervical spina bifida without hydrocephalus Q05.6 Thoracic spina bifida without hydrocephalus QØ5.7 Lumbar spina bifida without hydrocephalus Q05.8 Sacral spina bifida without hydrocephalus Q06.2 Diastematomyelia O O Pregnancy related peripheral neuritis Q85.00 Neurofibromatosis, unspecified Q85.01 Neurofibromatosis, type 1 Q85.02 Neurofibromatosis, type 2 R15.0-R51.9 Fecal incontinence R20.0-R20.9 Disturbance of skin sensation R25.0-R25.9 Abnormal involuntary movements R26.0-R26.9 Abnormalities of gait and mobility R27.0-R27.9 Other lack of coordination R29.0 Tetany R29.5 Transient paralysis R32 Unspecified urinary incontinence R39.14 Feeling of incomplete bladder emptying R49.8 Other voice and resonance disorders R53.81-R53.83 Other malaise and fatigue R Abnormal electromyogram [EMG] S04.5-S04.52 Injury of facial nerve S S04.9 Injury of other cranial nerves S S12.9 Fracture of cervical vertebra and othe parts of the neck S13.0-S13.9 Dislocation and sprain of joints and ligaments at neck level S S14.9 Injury of nerves and spinal cord at neck level S S Fracture of thoracic vertebra S24.0-S24.9 Injury of nerves and spinal cord at thorax level S S Fracture of lumbar vertebra S32.10-S32.19 Fracture of sacrum S32.2 Fracture of coccyx S34.01-S34.9 Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level S44.00-S44.92 Injury of nerves at shoulder and upper arm level S74.00-S74.92 Injury of nerves at hip and thigh level S84.00-S84.92 Injury of nerves at lower leg level Nerve Conduction Studies Sep 15 10

11 S94.00-S94.92 Injury of nerves at ankle and foot level T75.4 Electrocution CPT Codes Needle electromyography; 1 extremity with or without related paraspinal areas Needle electromyography; 2 extremities with or without related paraspinal areas Needle electromyography; 3 extremities with or without related paraspinal areas Needle electromyography; 4 extremities with or without related paraspinal areas Needle electromyography; larnyx Needle electromyography; hemidiaphragm Needle electromyography; cranial nerve supplied muscle(s), unilateral Needle electromyography; cranial nerve supplied muscle(s), bilateral Needle electromyography; thoracic paraspinal muscles (excluding T1 or T12) Needle electromyography; 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 Nerve conduction, amplitude and latency/velocity study, each nerve; motor, without f-wave study (code deleted 12/2012) Nerve conduction, amplitude and latency/velocity study, each nerve; motor, with f-wave study (code deleted 12/2012) Nerve conduction, amplitude and latency/velocity study, each nerve; sensory (code deleted 12/2012) 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; studies Nerve conduction studies; 13 or more studies Orbicularis oculi (blink) reflex, by electrodiagnostic testing H-reflex, amplitude and latency study; record gastrocnemius/soleus muscle (code deleted 12/2012) H-reflex, amplitude and latency study; record muscle other than gastrocnemius/soleus muscle (code deleted 12/2012) Neuromuscular junction testing (repetitive stimulation, paired stimuli), each nerve, any one method Unlisted neurological or neuromuscular diagnostic procedure Dynamic surface electromyography, during walking or other functional activities, 1-12 muscles HCPCS Codes N/A Nerve Conduction Studies Sep 15 11

12 Scientific Rationale Update September 2013 The American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) recommends that nerve conduction studies and electromyography should be performed and interpreted at the same time in the majority of situations. This is critically important in patients with suspected radiculopathy, plexopathy, myopathy, motor neuropathy, or motor neuron disease. In addition, the complementary information derived from electromyography is useful to ensure that an underlying disease process is not missed (eg, radiculopathy in a patient with suspected carpal tunnel syndrome). Scientific Rationale Update September 2012 There are two main types of electromyography (EMG), needle EMG (NEMG) and surface EMG (SEMG). NEMG, in combination with nerve conduction studies, is considered the gold standard methodology for assessing the neurophysiologic characteristics of neuromuscular diseases. SEMG is being investigated as a noninvasive alternative modality to NEMG. SEMG, also referred to as scanning EMG or surface scanning EMG, is a technique to measure muscle activity noninvasively using surface electrodes placed on the skin overlying the muscle. Unlike NEMG, SEMG electrodes record from a wide area of muscle territory, have a relatively narrow frequency band, have low-signal resolution, and are highly susceptible to movement artifact. SEMG can be conducted with the patient standing or lying down or performing an isometric hold, contraction, or exertion (static SEMG); performing a movement such as flexion and reextension (dynamic SEMG); responding to an increase or decrease of a physical challenge or undergoing combined static and dynamic investigations. A report on the clinical utility of surface EMG from the American Academy of Neurology (2000) concluded: Based on Class II data, SEMG is considered unacceptable as a clinical tool in the diagnosis of neuromuscular disease. Based on Class III and inconclusive or inadequate Class II data, SEMG is considered unacceptable as a clinical tool in the evaluation of patients with low back pain. Based on Class III data, SEMG is considered an acceptable tool for kinesiologic 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. The AAN recommends further studies comparing specificity and sensitivity of fine wire EMG with SEMG are to be encouraged. Peer review literature is very limited. Enomoto et al (2012) measured paravertebral muscle activity SEMG in lumbar degenerative patients and healthy volunteers. Muscle activity was tested in the standing position, and the influence of low back pain and alignment of the lumbar spine was assessed in the patients with lumbar kyphosis or canal stenosis. The subjects were kyphosis patients who were 60 years of age or older, age-matched lumbar spinal canal stenosis patients and healthy volunteers. Muscular activity at the L1-2 and L4-5 intervertebral areas was recorded by surface EMG in the resting standing position and also with a weight load held in Nerve Conduction Studies Sep 15 12

13 the standing position. Muscle activity and muscle fatigue, as well as the association between the visual analogue scale, Japanese Orthopaedic Association score for low back pain and muscle activity, were analyzed. Kyphosis patients had greater muscle activity in the lower back in the resting standing position and more severe muscle fatigue at the upper lumbar spine in comparison to patients with lumbar spinal canal stenosis. There was no association between muscle activity and clinical findings in patients with lumbar kyphosis although. Investigators concluded the study revealed the constant activity of paravertebral muscles and the susceptibility to muscle fatigue in patients with lumbar kyphosis. The quantification of muscle activity by surface EMG may show the pathology of lumbar kyphosis, and the decrease of muscle activity in the standing position may be a potentially useful index for guiding treatment. Uesugi et al (2011) sought to establish a non-invasive and quantitative analysis method using single-channel surface EMG (SEMG) for diagnosing neurogenic and myopathic changes. The subjects consisted of 66 healthy controls, 12 patients with neurogenic diseases, and 18 patients with myopathic diseases. The tibialis anterior muscle was examined using a belly to the adjacent bone lead. From each subject, signals of 1 s length were collected of various strengths. A new parameter, the "Clustering Index (CI)", was developed to quantify the uneven distribution of the SEMG signal, and was plotted against the SEMG area. The results were expressed as the Z-score of each subject calculated using linear regression from the normative data. When ±2.5 was used as the cut-off value of the Z-score, the specificity was 95%, whereas the sensitivity was 92% (11/12) and 61% (11/18) for the neurogenic and myopathic patients, respectively. There was no overlap of the Z-score values between the neurogenic and myopathic groups. Investigators concluded the CI method achieved a reasonably high diagnostic yield in detecting neurogenic or myopathic changes. Liu et al (2011) proposed modeling the activity coordination network between lumbar muscles using SEMG signals and performing the network analysis to compare the lumbar muscle coordination patterns between patients with low back pain (LBP) and healthy control subjects. Ten healthy subjects and eleven LBP patients were asked to perform flexion-extension task, and the SEMG signals were recorded. Both the subject-level and the group-level PC(fdr) algorithms are applied to learn the SEMG coordination networks with the error-rate being controlled. The network features are further characterized in terms of network symmetry, global efficiency, clustering coefficient and graph modules. The results indicate that the networks representing the normal group are much closer to the order networks and clearly exhibit globally symmetric patterns between the left and right SEMG channels. While the coordination activities between SEMG channels for the patient group are more likely to cluster locally and the group network shows the loss of global symmetric patterns. They concluded as a complementary tool to the physical and anatomical analysis, the proposed network analysis approach allows the visualization of the muscle coordination activities and the extraction of more informative features from the semg data for low back pain studies. Scientific Rationale Update December 2011 Schmidt et al. (2011) completed a study in which the authors compared the specificity and sensitivity of a hand-held NCS device for the detection of lumbosacral Nerve Conduction Studies Sep 15 13

14 radiculopathy with standard electrodiagnostic study (EDX). Fifty patients referred to a tertiary referral electromyography (EMG) laboratory for testing of predominantly unilateral leg symptoms (weakness, sensory complaints, and/or pain) were included in the investigation. Twenty-five normal "control" subjects were later recruited to calculate the specificity of the automated protocol. All patients underwent standard EDX and automated testing. Raw NCS data were comparable for both techniques; however, computer-generated interpretations delivered by the automated device showed high sensitivity with low specificity (i.e., many false positives) in both symptomatic patients and normal controls. The automated device accurately recorded raw data, but the interpretations provided were overly sensitive and lacked the specificity necessary for a screening or diagnostic examination. The official medical journal of the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) Muscle & Nerve, compared the specificity and sensitivity of the handheld NCS device for the detection of lumbosacral radiculopathy (LSR) with a standard electrodiagnostic study. The results showed the raw NCS data was comparable for both techniques; however, computer-generated interpretations delivered by the automated device showed high sensitivity with low specificity (i.e., many false positives) in both symptomatic patients and normal controls. The study noted above by Dr. Schmidt, results suggest the hand-held NCS device tested significantly over-diagnoses LSR in both symptomatic and asymptomatic subjects, which may lead to unnecessary intervention or repeated testing. The findings of the study do not support the clinical application of automated testing in the diagnosis of LSR. Scientific Rationale Update March 2011 Because nerve conduction studies performed with devices that use fixed anatomic templates and computer-generated reports (such as the NC-Stat device), are a local Medicare covered service in specific situations only, as dictated by certain local Medicare carriers, it must be covered for all Medicare Advantage members who reside in the local area in which coverage is applicable, subject to the relevant Medicare criteria and/or guidelines. Medicare does not expect this testing to be used routinely on all patients. For Local Medicare coverage determination, please go to the individual local Medicare website. Nerve Conduction Studies (NCS) (including Nerve Conduction Velocity Studies (NCV) and needle electromyography (EMG), typically performed together, and by a trained practitioner continue to be considered the gold standard of electrodiagnostic testing. Both NCVs and EMGs are used for a clinical diagnosis of peripheral nervous system disorders. Asad et al. (2010) compared the nerve conduction studies in clinically undetectable and detectable sensorimotor polyneuropathy in type 2 diabetics. Diagnosed diabetics (n = 60) were divided in two groups. Group 1 (n1 = 30) with clinically undetectable and group 2 (n2 = 30) with clinically detectable Diabetic Polyneuropathy. Detection of the sensorimotor neuropathy was done according to Diabetic Neuropathy Symptom Score and Diabetic Neuropathy Examination scores. The simplified nerve conduction studies protocol was followed in recording amplitudes, velocities and latencies of minimum two (Sural, Peroneal) and maximum six i.e. three sensory (Sural, Ulnar, Median) and three motor (Peroneal, Ulnar, Tibial) nerves. The comparisons were done between different parameters of nerve conduction studies with the neurological scores in undetectable and detectable groups using Pearson's chi square test. The amplitudes, velocities, latencies, outcome and grading of Nerve Conduction Studies Sep 15 14

15 neuropathy in nerve conduction studies when compared with neurological detection scores showed a significant relation in each group regarding evaluation (p = 0.005, p = 0.004, p = 0.05, p = , p = respectively). Diabetic Neuropathy Symptom Score and Diabetic Neuropathy Examination Score together can help in prompt evaluation of the diabetic sensorimotor polyneuropathy though nerve conduction study is more powerful test and can help in diagnosing subclinical cases. Scientific Rationale Update February 2009 (2007) The American Medical Association notes: Utilization of motor or sensory nerve conduction velocity studies at a frequency of 2 sessions per year would be considered appropriate for most conditions (e.g., unilateral or bilateral carpal tunnel syndrome, radiculopathy, mononeuropathy, polyneuropathy, myopathy, and neuromuscular junction disorders). (2006) The American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) states, The performance of or interpretation of NCS separately from the needle EMG component of the testing should clearly be the exception. Nerve conduction studies performed independent of needle EMG may only provide a portion of the information needed to diagnose muscle, nerve root, and most nerve disorders. When the NCS is used on its own without integrating needle EMG findings, or when an individual relies solely on a review of NCS data, the results can be misleading and important diagnoses may be missed. Moreover, individuals who interpret NCV data without patient interaction or who rely on studies that have delayed interpretation, who have interpretation made off-site, and who interpret results without complementary information obtained from EMG studies are not meeting the standards outlined in the AANEM policy recommendations. Except in limited clinical situations, evidence in the published, peer-reviewed scientific literature, textbooks and statements by the AANEM indicates that both nerve conduction studies (NCS) and needle electromyography (NEMG) are required to diagnose peripheral nervous system disorders. Circumstances under which NCS and EMG should not be performed together include, but are not limited to, limited follow-up studies of neuromuscular structures that have undergone previous electrodiagnostic evaluation, the current use of anticoagulants, the presence of lymphedema, or when a patient cannot tolerate the needle EMG procedure. In addition, the AANEM indicates that for suspected carpal tunnel syndrome, the extent of the needle EMG examination depends on the results of the NCSs and the differential diagnosis considered for the individual patient (AANEM, 2004). The table below summarizes the recommendations of the AANEM regarding the reasonable maximum number of studies per diagnostic category necessary for a physician to arrive at a diagnosis for 90% of patients with that final diagnosis (AANEM, 2004). Number of Services Recommended by the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM): Nerve Conduction Studies Sep 15 15

16 Nerve Conduction Studies Other EMG Studies Indications Needle EMG Motor NCV studies with and/or without F-wave Sensory NCV studies H- Reflex Neuromuscular Junction Testing (Repetitive Stimulation) Carpal tunnel (unilateral) Carpal tunnel (bilateral) Radiculopathy Mononeuropathy Polyneuropathy/Mononeuropathy Multiplex Myopathy Motor Neuropathy Plexopathy 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) Nerve Conduction Studies Sep 15 16

17 Devices Katz (2006) established a normal data set for median nerve studies in industrial workers using NC-stat technology. A total of 1695 individuals applying for employment at a single heavy industry plant without symptoms of carpal tunnel syndrome (CTS) were studied. Values for median distal motor latency (DML), amplitude, and F-waves were recorded in the dominant limbs. The DML was / milliseconds, with a 95 % cut-off value of 4.75 milliseconds. Amplitude of the compound muscle action potential was / mv, reflecting the use of volume conduction by this technology. Most of the workers who were characterized as having borderline, prolonged, or very prolonged distal motor latencies according to NeuroMetrix automated report actually fell below the 95 % cut-off of this independent data analysis. The author concluded that the NC-stat technology using DML appears to be no more sensitive or specific than a traditionally performed DML for the diagnosis of CTS. Until recently promoted sensory studies using NC-stat technology are better defined, this technology cannot be recommended for screening or diagnosis of CTS in an industrial population. (2006) The American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM), states that The standard of care in clinical practice dictates that using a predetermined or standardized battery of NCSs for all patients is inappropriate. It is the position of the AANEM that, except in unique situations, NCSs and needle EMG should be performed together in a study design determined by a trained neuromuscular physician. The AANEM explained that standardized nerve conduction studies performed independent of needle EMG studies may miss data essential for an accurate diagnosis. The American Academy of Neurology (AAN), and the American Academy of Physical Medicine and Rehabilitation (AAPM&R) indicate that "Testing should be performed using EDX (electrodiagnostic medicine) equipment that provides assessment of all parameters of the recorded signals. There is insufficient evidence to demonstrate equivalence or superiority of portable hand held automated devices, such as the NC-stat device or the Brevio NCS-Monitor, in comparison to conventional electrodiagnostic testing methods. The studies that were found are primarily case series, (Elkowitz et al. [2005], Kong et al. [2006], Vinik et al. [2004], Loeffler et al. [2000]). There are no randomized, controlled studies available to compare the NC-Stat device or the Brevio NCS Monitor to the current and convention electrodiagnostic testing that is done on symptomatic patients. Some of the studies were funded and /or written by employees of NeuroMetrix, the manufacturer of NC-Stat, which would reflect bias. The available evidence and diagnostic accuracy for these devices is limited in comparison with standard nerve conduction velocity studies and needle electromyography, which are considered the gold-standard testing methods. Larger independent studies would be needed to demonstrate the equivalence of NC-stat to traditional NCS in nerve conduction testing and the diagnoses of neuropathies. In addition, per the evidencebased guidelines, EMG studies should be available in the majority of cases, at the same time as the NCS, to enable a reliable diagnosis. Scientific Rationale Update November 2008 Measurement of nerve conduction speed is commonly performed to aid in the diagnosis of various disorders affecting the nerves of the upper extremities such as diabetic neuropathy (DN) and carpal tunnel syndrome (CTS). Diseased or damaged Nerve Conduction Studies Sep 15 17

18 nerves show decreased conduction speed or smaller-sized electrical signals. These are detected by stimulating the nerve with an electrode placed on the skin and capturing the time it takes for the nerve impulse to travel to a recording electrode. These types of nerve conduction studies (NCS) are traditionally carried out by a neurologist or other specialist in a specialized electromyographic laboratory, where other procedures such as electromyography (EMG; recording electrical activity directly within muscles through needle electrodes) are often necessary for diagnosis. A comprehensive diagnosis also relies on a variety of physical examinations, and may also involve imaging. Some examples of the automated nerve conduction studies (NCS) using hand held units being used without EMG's include the NC-Stat Monitor, the Brevio NCS-Monitor and the Neural-Scan Nerve Conduction Study sensory (NCSs) exam. A description of these devices is listed below: The NC-Stat Monitor (NeuroMetrix Inc.) is an automated handheld device using proprietary technology for conducting NCS. The available evidence for the NCstat monitor is limited in comparison with standard nerve conduction velocity studies and needle electromyography. NC-stat technology using distal motor latency (DML) appears to be no more sensitive or specific than a traditionally performed DML for the diagnosis of carpal tunnel syndrome. The Brevio NCS-Monitor (NeuMed Inc.) is a hand-held automated device designed to assess peripheral nerves for conditions such as carpal tunnel syndrome, diabetic peripheral neuropathy, and tarsal tunnel syndrome. There is insufficient evidence to establish the clinical value of this automated NCV studies device. This is not FDA approved. The Neural-Scan Nerve Conduction Study sensory (NCSs) exam helps to diagnose severity, location & distribution of radiculopathy or neuropathy. Noninvasive method. Measures sensory threshold using neuroselective frequency to test Type A-delta fibers. Abnormally high NCS measures indicate significant nerve conduction loss. Abnormally low NCS indicate hyperesthetic state that corresponds with inflamed, irritated or regenerating nerves. This is not FDA approved. (2006) The American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) has developed the following position statement in response to inquiries about: (1) physicians interpreting NCS data without any direct patient contact and without providing direct oversight over the performance of nerve conduction studies (NCSs); and (2) NCSs being utilized to diagnose patients without a complementary needle electromyography (EMG) study. The AANEM believes that electrodiagnostic studies should be performed by physicians properly trained in electrodiagnostic medicine, that interpretation of NCS data alone absent face-to-face patient interaction and control over the process provides substandard care, and that the performance of NCSs without needle EMG has the potential of compromising patient care. It is the AANEM s opinion that it is in the best interest of patients, in the majority of situations, for the needle EMG and the NCS examination to be conducted and interpreted at the same time. Nerve Conduction Studies Sep 15 18

19 Standard Nerve Conduction Velocity Testing Automated Nerve Testing Systems Includes safeguards and procedures to assure proper performance and interpretation. Involves electrical stimulation of peripheral nerves, and recording of electrical responses from the same peripheral nerve or from a muscle. Many of the safeguards used with standard nerve conduction studies are not used in these systems. Similar to standard nerve conduction velocity testing in that both involve electrical stimulation of peripheral nerves, and recording of electrical responses from the same peripheral nerve or from a muscle. However, these devices have a number of differences with standard nerve conduction velocity tests. Done in the office by office staff The physician specialist and a registered technologist perform the testing. Velocity tests can stimulate and record Only several specific nerves can be both proximally and distally. tested. Orthodromic and antidromic conduction Only one direction of conduction is is available. available. The technique of standard nerve A single specific technique is conduction velocity tests varies predetermined. according to the patient's situation. EMG is always available. Standard nerve conduction velocity testing, stimulator and recording sites can be moved around to find optimal locations. The clinician assesses latencies, amplitudes, configurations, and conduction velocities. The clinician critiques tracings, and determines if repeat recordings needed. The clinician takes into account the patient s history, physical, nerve conduction velocities and EMG as needed when interpreting the results. The clinician also considers normal variants. EMG is generally not available at the point of service. Stimulator and recording sites are placed at predetermined anatomic locations with automated devices. By contrast, a computer scores amplitudes and latencies, and determines if tests are normal according to a look-up table. The computer prints an automated interpretation statement for the physician to sign; the computer s statement is taken from a programmed list of statements. Test preset nerves only. Nerve Conduction Studies Sep 15 19

20 Standard Nerve Conduction Velocity Automated Nerve Testing Testing Systems A trained clinician scores peaks, A computer scores amplitudes and latencies, determines if tests are latencies, and determines if tests are normal, adjusted to clinically relevant normal according to a look-up table. factors. The clinician assesses latencies, The computer prints an automated amplitudes, configurations, and interpretation statement for the conduction velocities. The clinician physician to sign; the computer s critiques tracings, and determines if statement is taken from a repeat recordings needed. The clinician programmed list of statements. takes into account the patient s history, physical, nerve conduction velocities and EMG as needed when interpreting the results. The clinician also considers normal variants. Velocity testing, stimulator and Stimulator and recording sites are recording sites can be moved around to placed at predetermined anatomic find optimal locations. locations. (2008) No studies were identified that addressed the utility of automated nerve conduction tests in a clinical setting. Particularly needed are data on the sensitivity and specificity of automated nerve conduction tests performed at the point-of-care in comparison with the gold standard of laboratory EMG. Overall, evidence remains insufficient to evaluate the effect of point-of-care automated nerve conduction tests on health outcomes. Scientific Rationale Update June 2007 The NC-stat System (NeuroMetrix Inc.) is a portable, hand-held, noninvasive, automated nerve conduction-testing device that has been marketed for use in an office or clinic setting. The device was originally approved for testing of motor conduction in the median and ulnar nerves in the wrist; approval was subsequently expanded to include sensory testing in the wrist as well as for NCS in the lower limbs. The purpose of the NC-stat System is to assist in the diagnosis of peripheral nerve disorders, such as carpal tunnel syndrome and diabetic peripheral neuropathy. This device consists of four components which include single-use biosensors, a battery powered monitor that connects to the sensors and stores information, a docking station for the monitor, and the on Call Information System, (which is a remote report generation system to which test data are transmitted for analysis). A computerized system interprets the data, which is capable of being transmitted to the treating physician within minutes. The NC-stat System received FDA approval in 1998, through the 510(k) approval process, for measurement of neuromuscular signals that are useful in diagnosing and evaluating systemic and entrapment neuropathies. This original approval was for use as an adjunct to, and not as a replacement for, conventional electrodiagnostic testing. In an updated position statement on the proper performance and interpretation of electrodiagnostic studies from the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM, 2006), although no specific reference to portable, automated nerve conduction testing devices, (i.e., the NC-stat device) is made, the following comments were noted: Nerve Conduction Studies Sep 15 20

21 1. Nerve conduction studies performed independent of needle electromyography (EMG) may only provide a portion of the information needed to diagnose muscle, nerve root, and most nerve disorders; 2. When the nerve conduction study (NCS) is used on its own without integrating needle EMG findings or when an individual relies solely on a review of NCS data, the results can be misleading, and important diagnoses may be missed; 3. Individuals without medical education in neuromuscular disorders and without special training in electrodiagnostic procedures typically are not qualified to interpret the waveforms generated by NCS and needle EMG or to correlate the findings with other clinical information to reach a diagnosis. In 2005, the Washington State Department of Labor and Industries conducted a technology assessment of the NC-stat System to evaluate the available peerreviewed literature on this device, following inquiries from physicians in the local practice community, as well as from staff of the Department of Labor and Industries. This technology assessment reviewed results from six articles in May of 2005, and an additional two articles were reviewed in 2006 to update the review. The report concluded that the NC-stat System is not equivalent to conventional methods for nerve conduction velocity testing (Morse, 2006). To date, there has been very limited published evidence to demonstrate the safety and efficacy of automated, noninvasive nerve conduction testing devices, such as the NC-stat device, as compared to conventional Gold standard electrodiagnostic testing using needle electromyography (EMG) and nerve conduction velocity studies (NCS). There is little evidence evaluating the efficacy of the NC-stat and most of the published clinical studies have only evaluated use of the device for assessment of median and ulnar nerves (Katz, 2006; Kong, 2006). Katz et al (2006) have reported Nc-stat is no more sensitive or specific than a traditionally performed distal motor latency for the diagnosis of carpal tunnel syndrome. In addition, the diagnostic accuracy for other conditions involving the lower extremities has not been demonstrated. Most of the published literature on the NC-stat device, involved unblinded assessments where persons affiliated with the manufacturer were principal investigators or co-authors (Leffler et al, 2000; Vinik et al, 2004; Kong et al, 2006; Megerian and Gozani, 2006). Larger, independent, controlled studies would be needed to demonstrate the equivalence of NC-stat to traditional NCS in nerve conduction testing and the diagnoses of neuropathies; data from these trials are needed to demonstrate its safety and efficacy in the long-term. Scientific Rationale - Initial Nerve Conduction Studies (NCS), or Nerve Conduction Velocity (NCV), is a test of the speed of conduction of impulses through a nerve. They measure action potentials resulting from peripheral nerve stimulation recordable over the nerve or from an innervated muscle. The nerve is stimulated, usually with surface electrodes, which are patch-like electrodes (similar to those used for ECG) placed on the skin over the nerve at various locations. One electrode stimulates the nerve with a very mild Nerve Conduction Studies Sep 15 21