Electromyography and Neuromuscular Disorders: Clinical-Electrophysiologic Correlations (Expert Consult - Online and Print)

Diagnose neuromuscular disorders more quickly and accurately with Electromyography and Neuromuscular Disorders: Clinical-Electrophysiologic Correlations, 3rd Edition! State-of-the-art guidance helps you correlate electromyographic and clinical findings and use the latest EMG techniques to their fullest potential.Consult this title on your favorite e-reader with intuitive search tools and adjustable font sizes. Elsevier eBooks provide instant portable access to your entire library, no matter what device you're using or where you're located.Successfully correlate electrodiagnostic findings with key clinical findings for more confident diagnoses.Clearly see how to apply what you've learned with abundant case studies throughout the book.Obtain relevant clinical guidance quickly and easily with an accessible, easy-to-read writing style that's both comprehensive and easy to understand. Ensure correct EMG needle placement and avoid neurovascular injuries by referring to more than 65 detailed, cross-sectional anatomy drawings.Diagnose many newly defined genetic neuromuscular conditions based on their electrodiagnostic presentation.Stay up to date with must-know information on iatrogenic complications of electrodiagnostic studies.Visualize key concepts more easily with a brand-new full-color design, new artwork, and new photographs.Access Electromyography and Neuromuscular Disorders online, fully searchable, at www.expertconsult.com, along with more than 70 videos that allow you to see and hear the EMG waveforms discussed in the text, as well as a convenient'test yourself'module. Electromyography and Neuromuscular Disorders......Page 2 Copyright Page......Page 5 Foreword......Page 6 Preface to the Third Edition......Page 7 Preface to the Second Edition......Page 8 Preface to the First Edition......Page 10 Dedication......Page 11 Acknowledgments......Page 12 Localization of the Disorder is the Major Aim of the Electrodiagnostic Study......Page 13 Neuropathic Localization......Page 14 Assessment of the Temporal Course can Often be Made......Page 15 Neuromuscular Junction Localization......Page 16 Cardinal Rules of Nerve Conduction Studies and Electromyography......Page 17 Anatomy......Page 20 Physiology......Page 22 Classification......Page 26 Recording......Page 28 Suggested Readings......Page 30 Motor Conduction Studies......Page 31 Duration......Page 32 Conduction Velocity......Page 33 Peak Latency......Page 34 Conduction Velocity......Page 35 Lesions Proximal to the Dorsal Root Ganglion Result in Normal Sensory Nerve Action Potentials......Page 36 Proximal Stimulation: Normal Temporal Dispersion and Phase Cancellation......Page 37 Mixed Conduction Studies......Page 38 Use Supramaximal Stimulation......Page 39 Neuropathic Lesions......Page 40 Axonal Loss......Page 41 Demyelination......Page 43 Conduction Block......Page 44 Suggested Readings......Page 47 4 Late Responses......Page 48 F Response......Page 49 F Response Procedure......Page 50 The F Estimate......Page 52 H Reflex......Page 53 Axon Reflex......Page 56 Suggested Readings......Page 58 Blink Reflex Procedure......Page 59 Patterns of Abnormalities......Page 61 Suggested Readings......Page 63 Normal Neuromuscular Junction Physiology......Page 64 Modeling Slow Repetitive Nerve Stimulation......Page 65 Repetitive Nerve Stimulation in the Electromyography Laboratory......Page 67 Exercise Testing in the Electromyography Laboratory......Page 68 Stimuli must be Supramaximal......Page 69 Nerve Selection......Page 70 Decrement and Increment Calculation......Page 71 Repetitive Nerve Stimulation Protocol......Page 72 Suggested Readings......Page 73 Routine Ulnar Conduction Study: Pseudo-Conduction Block between the Wrist and Below-Elbow Sites......Page 74 Ulnar Conduction Study: Proximal Martin–Gruber Anastomosis and Pseudo-Conduction Block between the Below-Elbow and Above-Elbow Sites......Page 75 Ulnar Conduction Study Recording the First Dorsal Interosseous: Pseudo-Conduction Block between the Wrist and Below-Elbow Sites......Page 76 Routine Median Motor Study: Increased Compound Muscle Action Potential Amplitude Proximally......Page 77 Martin–Gruber Anastomosis and Carpal Tunnel Syndrome: Positive Proximal Deflection (“Dip”) and Factitiously Fast Conduction Velocity......Page 78 Needle Electromyography and Martin–Gruber Anastomosis......Page 79 Miscellaneous Anatomic Variations......Page 80 Suggested Readings......Page 82 Temperature......Page 83 Age......Page 85 Electrode Impedance and Noise......Page 86 Filters......Page 87 Stimulus Artifact......Page 88 Cathode Position: Reversing Stimulator Polarity......Page 89 Co-stimulation of Adjacent Nerves......Page 91 Electrode Placement for Motor Studies......Page 93 Antidromic versus Orthodromic Recording......Page 94 Distance between Recording Electrodes and Nerve......Page 95 Distance between Active and Reference Recording Electrodes......Page 96 Limb Position and Distance Measurements......Page 98 Limb Position and Waveform Morphology......Page 100 Suggested Readings......Page 101 9 Basic Statistics for Electrodiagnostic Studies......Page 102 Bayes’ Theorem and the Predictive Value of a Positive Test......Page 105 Multiple Tests and the Increasing Risk of False Positives......Page 107 Suggested Readings......Page 108 Key Points:......Page 109 Stimulation Sites:......Page 110 Key Points:......Page 111 Key Points:......Page 112 Stimulation Sites:......Page 113 Key Points:......Page 114 Stimulation Sites:......Page 115 Distal Distance:......Page 116 Distal Distance:......Page 117 Key Points:......Page 119 Stimulation Sites:......Page 120 Stimulation Site:......Page 121 Distal Distance:......Page 122 Key Points:......Page 123 Upper Extremity......Page 124 Craniobulbar......Page 126 Stimulation Sites:......Page 127 Key Points:......Page 128 Key Points:......Page 131 Distal Distance:......Page 132 Stimulation Sites:......Page 133 Key Points:......Page 134 Key Points:......Page 135 Nerve Conduction Studies of the Lower Extremity: Normal Adult Values......Page 136 Equipment......Page 137 Typical Needle Electromyography Examination (Box 12–1)......Page 139 Cross-section Anatomy Key Points:......Page 141 Cross-section Anatomy Key Points:......Page 144 Cross-section Anatomy Key Points:......Page 148 Cross-section Anatomy Key Points:......Page 151 Cross-section Anatomy Key Points:......Page 154 Cross-section Anatomy Key Points:......Page 157 Cross-section Anatomy Key Points:......Page 160 Cross-section Anatomy Key Points:......Page 164 Cross-section Anatomy Key Points:......Page 167 Cross-section Anatomy Key Points:......Page 170 Cross-section Anatomy Key Points:......Page 173 Cross-section Anatomy Key Points:......Page 176 Cross-section Anatomy Key Points:......Page 179 Cross-section Anatomy Key Points:......Page 182 Cross-section Anatomy Key Points:......Page 186 Cross-section Anatomy Key Points:......Page 190 Cross-section Anatomy Key Points:......Page 193 Cross-section Anatomy Key Points:......Page 197 Cross-section Anatomy Key Points:......Page 200 Cross-section Anatomy Key Points:......Page 203 Cross-section Anatomy Key Points:......Page 206 Cross-section Anatomy Key Points:......Page 209 Cross-section Anatomy Key Points:......Page 212 Cross-section Anatomy Key Points:......Page 216 Cross-section Anatomy Key Points:......Page 221 Cross-section Anatomy Key Points:......Page 225 Cross-section Anatomy Key Points:......Page 229 Morphology......Page 232 Firing Characteristics......Page 235 Endplate Spikes (“Nerve Potentials”)......Page 236 Fibrillation Potentials......Page 237 Positive Sharp Waves......Page 238 Myotonic Discharges......Page 240 Fasciculation Potentials......Page 241 Myokymic Discharges......Page 242 Neuromyotonic Discharges......Page 243 Suggested Readings......Page 246 Physiology......Page 247 Morphology......Page 248 Duration......Page 249 Polyphasia, Serrations, and Satellite Potentials......Page 250 Stability......Page 251 Firing Pattern (Activation, Recruitment, Interference Pattern)......Page 252 Acute Axonal Loss......Page 255 Chronic Axonal Loss......Page 256 Neuromuscular Junction Disorders......Page 257 Suggested Readings......Page 259 Axonal Loss Lesions......Page 261 Demyelinating Lesions......Page 262 Axonal Loss: Acute......Page 264 Axonal Loss: Chronic......Page 265 Demyelination (Slowing and Conduction Block): Single Distal Lesion......Page 266 Myopathic Lesions......Page 267 Myopathy: Chronic with Denervating Features......Page 268 Central Nervous System Lesions......Page 269 Mononeuropathy: Non-localizing......Page 270 Polyneuropathy: Asymmetric Axonal......Page 271 Plexopathy......Page 272 Motor Neuron Disease......Page 273 Myopathy: Distal......Page 274 Myopathy with Myotonic Discharges......Page 275 Localizing a Mononeuropathy by Needle EMG: Issues and Limitations......Page 276 Anatomy......Page 279 Clinical......Page 281 Etiology......Page 283 Nerve Conduction Studies......Page 284 Median Second Lumbrical-versus-Ulnar Interossei Distal Motor Latencies......Page 286 Inching across the Wrist and Palmar Stimulation......Page 287 Wrist-to-Palm versus Palm-to-Digit Sensory Conduction Velocity (Segmental Sensory Conduction Studies across the Wrist)......Page 289 Electromyographic Approach......Page 292 Special Situation: EDX Studies after Carpal Tunnel Release......Page 293 Suggested Readings......Page 300 Etiology......Page 301 Ligament of Struthers Entrapment......Page 302 Anterior Interosseous Nerve Syndrome......Page 303 Nerve Conduction Studies......Page 304 Electromyographic Approach......Page 305 Suggested Readings......Page 309 Anatomy......Page 310 Clinical......Page 311 Differential Diagnosis......Page 313 Nerve Conduction Studies......Page 314 Differential Slowing: Flexed versus Extended Elbow Conduction Techniques......Page 316 Short Segment Incremental Studies (“Inching”)......Page 317 Recording the First Dorsal Interosseous......Page 318 Mixed and Sensory Nerve Conductions......Page 319 Dorsal Ulnar Cutaneous Sensory Study......Page 320 Nerve Conduction Study Pitfalls......Page 322 Electromyographic Approach......Page 323 Suggested Readings......Page 329 Clinical......Page 331 Differential Diagnosis......Page 333 Dorsal Ulnar Cutaneous Sensory Study......Page 334 Median Second Lumbrical versus Ulnar Interossei Distal Motor Latencies......Page 335 Short Segment Incremental Studies......Page 336 Comparison of the Various Electrophysiologic Tests in Ulnar Neuropathy at the Wrist......Page 337 Electromyographic Approach......Page 338 Suggested Readings......Page 342 Anatomy......Page 343 Radial Nerve between the Spiral Groove and the Bifurcation near the Elbow......Page 344 Deep Branch......Page 345 Posterior Interosseous Neuropathy......Page 346 Differential Diagnosis......Page 347 Nerve Conduction Studies......Page 348 Anatomic Considerations of Some Radial-Innervated Muscles on Needle EMG......Page 351 Suggested Readings......Page 357 Anatomy......Page 358 Peroneal Neuropathy at the Fibular Neck......Page 360 Etiology......Page 361 Nerve Conduction Studies......Page 362 Electromyographic Approach......Page 363 Suggested Readings......Page 368 Clinical......Page 369 Differential Diagnosis......Page 370 Nerve Conduction Studies......Page 371 Electromyographic Approach......Page 372 Suggested Readings......Page 376 Clinical......Page 377 Nerve Conduction Studies......Page 378 Electromyographic Approach......Page 380 Suggested Readings......Page 383 Trigeminal Nerve......Page 384 Facial Neuropathy......Page 386 Trigeminal Neuropathy......Page 387 Nerve Conduction Studies......Page 388 Nerve Conduction Studies and Blink Reflex......Page 389 Electromyographic Approach......Page 390 Suggested Readings......Page 395 Key Question No. 1: What is the Temporal Course and Progression of the Polyneuropathy (Acute, Subacute, Chronic; Progressive, Stepwise, Relapsing/Remitting)?......Page 396 Key Question No. 2: Which Fiber Types are Involved (Motor, Large Sensory, Small Sensory, Autonomic)?......Page 397 Key Question No. 3: What is the Pattern of the Polyneuropathy (Distal Dying Back [Distal-To-Proximal Gradient], Short Nerves, Multiple Nerves; Symmetry, Asymmetry)?......Page 398 Key Question No. 5: Is there a Family History of Polyneuropathy?......Page 399 Key Question No. 6: Is there a History of Medical Illness or are there Signs Suggesting A Medical Illness Associated with Polyneuropathy?......Page 400 Special Situations in Axonal Polyneuropathy: The Use of the Sural/Radial Amplitude Ratio in Mild Polyneuropathy......Page 401 Diabetes......Page 402 Demyelinating Polyneuropathy......Page 403 Guillain–Barré Syndrome (GBS)......Page 404 Electrophysiology......Page 405 Charcot–Marie–Tooth Neuropathy......Page 406 Electrophysiology......Page 407 Multifocal Motor Neuropathy with Conduction Block......Page 408 Electrophysiologic Evaluation of Polyneuropathy......Page 409 Nerve Conduction Studies......Page 410 Electromyographic Approach......Page 411 Suggested Readings......Page 427 Classic Amyotrophic Lateral Sclerosis......Page 429 Primary Lateral Sclerosis......Page 430 Cervical/Lumbar Stenosis......Page 431 Inclusion Body Myositis......Page 432 Nerve Conduction Studies......Page 433 Electromyographic Approach......Page 437 Suggested Readings......Page 442 28 Atypical Motor Neuron Disorders......Page 444 West Nile Encephalitis......Page 445 Familial Amyotrophic Lateral Sclerosis (FALS)......Page 446 Hereditary Spastic Paraplegia......Page 447 Adult Polyglucosan Body Disease......Page 448 Monomelic Amyotrophy......Page 449 Delayed Radiation-Induced Motor Neuron Syndrome......Page 450 Nerve Conduction Studies......Page 451 Electromyographic Approach......Page 452 Suggested Readings......Page 459 Etiology......Page 460 Nerve Conduction Studies......Page 461 Superficial Peroneal SNAP and L5 Radiculopathy: the Rare Exception......Page 464 Electromyographic Approach......Page 466 Time Course in Radiculopathy......Page 467 If the Sensory Nerve Root is Predominantly Affected, the Electromyographic Study will be Normal......Page 469 Abnormal Paraspinal Muscles are Useful in Identifying a Radiculopathy but Not the Segmental Level of the Lesion......Page 470 There is no Difference between a Radiculopathy/Polyradiculopathy and Focal/Diffuse Motor Neuron Disease on the Electromyographic Study......Page 472 Fibrillation Potentials in the Paraspinal Muscles do not Necessarily Imply Radiculopathy......Page 473 In the Elderly, it may not be Possible to Differentiate a Mild Chronic Distal Polyneuropathy from Mild Chronic Bilateral L5–S1 Radiculopathies......Page 474 Suggested Readings......Page 479 Anatomy......Page 480 Clinical......Page 481 Lower Trunk Plexopathy......Page 482 Neoplasms and Other Mass Lesions......Page 483 Delayed Radiation Injury......Page 484 Thoracic Outlet Syndrome......Page 485 Nerve Conduction Studies......Page 486 Electromyographic Approach......Page 489 Neurogenic Thoracic Outlet Syndrome......Page 490 Suggested Readings......Page 498 Clinical......Page 499 Electrodiagnosis......Page 501 Anatomy......Page 502 Electrodiagnosis......Page 503 Clinical......Page 504 Clinical......Page 505 Clinical......Page 506 Electrodiagnosis......Page 507 Suggested Readings......Page 511 Obturator Nerve......Page 513 Clinical......Page 514 Retroperitoneal Hemorrhage......Page 515 Tumors and Other Mass Lesions......Page 517 Postpartum Plexopathy......Page 518 Lateral Femoral Cutaneous Neuropathy (Meralgia Paresthetica)......Page 519 Nerve Conduction Studies......Page 520 Electromyographic Approach......Page 521 Normal Paraspinal Muscles on EMG do not Exclude a Radiculopathy......Page 522 If the Lesion is Acute, the Study may be Normal......Page 523 Suggested Readings......Page 529 Clinical......Page 530 Etiology......Page 532 Piriformis Syndrome......Page 533 Nerve Conduction Studies......Page 534 Special Studies in Suspected Piriformis Syndrome......Page 535 Electromyographic Approach......Page 536 Suggested Readings......Page 540 Myasthenia Gravis......Page 541 Clinical......Page 542 Nerve Conduction Studies......Page 543 Electromyography......Page 544 Single-fiber Electromyography......Page 545 Electrophysiologic Evaluation......Page 547 Clinical......Page 549 Electrophysiologic Evaluation......Page 550 Congenital Myasthenic Syndromes......Page 551 Suggested Readings......Page 559 35 Myopathy......Page 561 Clinical......Page 562 Electromyographic Approach......Page 563 Spontaneous Activity in Myopathies......Page 564 Motor Unit Action Potential Analysis in Myopathies......Page 565 Single-fiber Electromyography in Myopathy......Page 566 Polymyositis and Dermatomyositis......Page 567 Critical Illness Myopathy......Page 568 Suggested Readings......Page 573 Muscle Cooling......Page 575 Prolonged Exercise Test......Page 576 Myotonic Dystrophy......Page 578 Clinical......Page 579 Electrophysiologic Evaluation......Page 581 Electrophysiologic Evaluation......Page 582 Electrophysiologic Examination......Page 583 Paramyotonia Congenita......Page 584 Clinical......Page 585 Electrophysiologic Examination......Page 586 Electrophysiologic Examination......Page 587 Other Conditions Associated with Myotonia......Page 588 Suggested Readings......Page 593 Differential Diagnosis of Neurologic Weakness in the ICU......Page 595 Electrodiagnostic Studies in the Intensive Care Unit: Technical Issues......Page 597 Low or Absent Motor Responses with Normal Sensory Responses......Page 599 Decreased Activation......Page 601 Nerve Conduction and Electromyographic Protocol in the Intensive Care Unit......Page 602 Phrenic Motor Study......Page 603 Suggested Readings......Page 604 Maturation Issues......Page 605 Technical Issues......Page 607 Approach to the Child as a Patient......Page 608 Goals of the Pediatric Electrodiagnostic Examination......Page 610 Suggested Readings......Page 611 Basics of Electricity......Page 612 Ohm’s Law......Page 613 Kirchhoff’s Laws......Page 614 Resistors in Parallel......Page 615 Direct Current and Alternating Current......Page 616 Capacitance......Page 617 Inductance......Page 619 Waveforms, Frequency Analysis, and Filtering......Page 620 Low-Frequency (High-Pass) Filters......Page 621 High-Frequency (Low-Pass) Filters......Page 622 Practical Implications for Electrodiagnostic Studies......Page 623 Electrical Issues......Page 626 Central Lines and Electrical Wires......Page 628 Implanted Pacemakers and Cardioverter-Defibrillators......Page 629 Pneumothorax......Page 630 Bleeding......Page 631 Coexistent Medical Conditions......Page 632 Needle Electromyography and Patients at Risk of Bleeding......Page 633 Infection......Page 634 Suggested Readings......Page 635 Palmar Mixed Nerve Studies......Page 637 Phrenic Motor Study*......Page 638 Motor Studies......Page 639 Late Responses*......Page 640 Mean Motor Unit Action Potential Duration Based on Age and Muscle Group......Page 641

Diagnose neuromuscular disorders more quickly and accurately with Electromyography and Neuromuscular Disorders: Clinical-Electrophysiologic Correlations, 3rd Edition! State-of-the-art guidance helps you correlate electromyographic and clinical findings and use the latest EMG techniques to their fullest potential.

• Successfully correlate electrodiagnostic findings with key clinical findings for more confident diagnoses.
• Clearly see how to apply what you've learned with abundant case studies throughout the book.
• Obtain relevant clinical guidance quickly and easily with an accessible, easy-to-read writing style that's both comprehensive and easy to understand.

• Ensure correct EMG needle placement and avoid neurovascular injuries by referring to more than 65 detailed, cross-sectional anatomy drawings.
• Diagnose many newly defined genetic neuromuscular conditions based on their electrodiagnostic presentation.
• Stay up to date with must-know information on iatrogenic complications of electrodiagnostic studies.
• Visualize key concepts more easily with a brand-new full-color design, new artwork, and new photographs.
• Access Electromyography and Neuromuscular Disorders online, fully searchable, at www.expertconsult.com, along with more than 70 videos that allow you to see and hear the EMG waveforms discussed in the text, as well as a convenient "test yourself" module.