Cambridge University Press 978-1-107-56203-5 — Comprehensive Electromyography Mark A

Cambridge University Press 978-1-107-56203-5 — Comprehensive Electromyography Mark A. Ferrante Index More Information

Index

A waves, 148–149 action potentials (AP), 34, 49, 59. in magnetic field, 26–28 AANEM. See American Association of See also absolute; compound Ohm’s law on, 23 Neuromuscular and muscle action potential; motor reversals in, 23, 36 Electrodiagnostic Medicine unit action potential; muscle voltage in, 23–24 abductor pollicis brevis (APB), 318 fiber APs; relative refractory alternating current (AC) signal aberrant reinnervation, 223 period; sensory nerve action of 60 Hz power artifact, 276–278 abnormal RNSS, 156 potential in capacitors, 36–37 absolute abnormal, 284 duration of, 63–64 dangers of, 290–291 absolute refractory period, 58–59 of F wave, 146 in high pass filter, 38 AC. See alternating current focal axon loss and, 124 in low pass filter, 38 accessory deep peroneal nerve, 269–270 focal demyelination and, 123–124 quantification of, 24–26 accommodation, 59 of nerve fibers, 99–100, 111 aluminum, 27–28 acetate, 69 of recording electrode, 90–91 American Association of acetylcholine (ACh), 68 activation gate, of VGNC, 258 Neuromuscular and binding, 70–71 activation phase Electrodiagnostic Medicine exocytosis and, 69 of MUAP assessment, 193–194 (AANEM), 290, 298, 306–307 release, 71–72 of needle EMG, 173, 235 AMP. See adenosine monophosphate in synaptic space, 69 activation time, of muscle, 107 amphiphilic molecules, 49 synthesized, 69 active electrode, 87–88. See also bipolar amplifiers vesicles, 69, 71–72, 152–153 recordings; E1 electrode; ADC, DAC for, 45 acetylcholine receptors (AChR), 152, referential recordings differential, 45–47 200–201 active release zones, 68 for EMG machines, 45, 47 in LEMS, 253 acute compression, 229–230 gain on, 44 in myasthenia gravis, 252 acute inflammatory demyelinating inverting, 46 acetylcholinesterase (AChE), 69 polyradiculoneuropathy monopolar, 44–45 ACh. See acetylcholine (AIDP), 249 non-inverting, 46 ACh receptors (AChRs), 68–70 acute poliomyelitis, 237 resistance, 44 AChE. See acetylcholinesterase ADC. See analog-to-digital converter signal-to-noise ratio for, 47 AChRs. See acetylcholine receptors adductor pollicis muscle, 264–265 amplitude, 25 acquired axon loss polyneuropathies, adenosine monophosphate (AMP), 78 absolutely, relatively abnormal, 102 247–248 adenylate kinase, 78 baseline-to-peak, 113 acquired demyelinating adhesive surface recording electrodes, body tissue and, 103 polyneuropathies, 248–250 89 CMAP, 103–104 actin, 74 ADP, 75–76, 78 decrement, 100 action at a distance, 7 age-related issues discrepancy, in DMCB, 130 action potential (AP) generation, 59 in NCS, 260–261 of fibrillation potentials, 185 action potential (AP) propagation, 61 in needle EMG, 261 of H wave antidromic, orthodromic conduction as pitfalls, 260–261 abnormal, 145 in, 92–93 agrin, 70 in EMG laboratory, 144–145 block, 124 AHCs. See anterior horn cells measurements of, 144–145 conduction velocity of, 62–63 AIDP. See acute inflammatory low, peroneal-EDB, 285 toward E1 electrode, 102 demyelinating measurement of, 102–104 in excitation-contraction coupling, 74 polyradiculoneuropathy of motor axons, 103 length constant in, 125 aliasing, 42 of motor NCS, 100 of myelin, 61–63 alkaline batteries, 11 of motor response, 104, 135, 216 physiologic, 93 alpha gamma coactivation, 77 of MUAP, 165, 173–176, 195 safety factor of, 125–126 ALS. See amyotrophic lateral sclerosis negative AUC and, 104–105, 132 saltatory conduction in, 64 alternating current (AC), 14, 23 peak-to-peak, 113 speed, 62–65, 123–124, 132 cycle of, 24–25, 27 response, very low, 284–285

513

Index

amplitude (cont.) axon loss, 123. See also acquired axon bleeding in sensory NCS, 113–114 loss polyneuropathies; chronic in needle EMG, 295–296 of sensory response, 135, 216 motor axon loss safety issues of, 295–296 synchrony and, 103 approach to, in surgical intervention, blink reflexes, 149–150 of tibial response, 100 225–226 blocking, 200, 205 amplitude values, 85 conduction failure and, 131–132 blood-nerve barrier, 66 amyotrophic lateral sclerosis (ALS), DMCB and, 214 BMI. See body mass index 132, 238 EDX features of, 248 body habitus-related issues analog filters, 40–41 focal, 124, 202 gender in, 262 analog-to-digital converter (ADC), lesions, 215–216 as pitfalls, 261–262 41–43, 45 needle EMG study of, 215–216 weight as, 262 anastomosis. See also Martin-Gruber proximal lesion and, 147 body mass index (BMI), 262 anastomosis sensory response and, 135–136 body tissue, 103 Berretini, 269 axonotmesis, 222 brachial plexus in forearm, 268 axoplasm, 50 composition of, 242–243 median-to-ulnar, 262 plexopathies of, 242–245 Riche–Cannieu, 268–269 B. See bel preterminal nerves of, 242–243 ulnar-to-median, 268 backfire animal electricity (Galvani), 76 of motor neurons, 146 cable properties, 60 anisotropic band, 75 time, 146–147 calcinosis cutis, 299 anodal block, 279 bandpass filter, 40 can’t let-go currents, 291 anode, 11, 21–22, 43 bandwidth, of frequencies, 35 capacitance, 22 anode rotation, 273–275 basal firing rate, 165 DC circuit and, 33–34 anomalous innervations, 262 baseline train, 154 of membrane, 61–62 anterior horn cells (AHCs), 50, 68, 73, baseline-to-peak amplitude, 113 total membrane, 60 79–80 batteries capacitive coupling, 45 acute poliomyelitis and, 237 alkaline, 11 capacitive current, 21 disorders, 236–237 capacitors and, 21–22 capacitive reactance, 36 in motor unit, 79–80, 162–163 electrochemical cells and, 11 capacitors, 8. See also RC circuit post-poliomyelitis syndrome and, lead-acid automotive, 11 AC signal in, 36–37 237–238 transistor, 11 batteries and, 21–22 SMA-3 and, 238–239 voltage in, 10–11, 18 charge in, 21–23 antidromic conduction, 92–93 zinc-carbon, 11 current and, 20–23 antidromic sensory NCS, 111, 114–116 bel (B), 26 DC signal in, 38–39 AP. See action potentials Bell, Alexander Graham, 26 defining, 21 APB. See abductor pollicis brevis belly-tendon method, 95–96 in EDX medicine, 20–21 apparent single fiber APs (ASFAPs), 206 Berretini anastomosis, 269 electrons and, 31 arborization point, 183 bidirectional propagation, 74 filters and, 34, 36 area under the curve (AUC), 101 bilateral hand numbness and tingling, as frequency-dependent resistor, 38 DMCB and, 129 exercise, 332, 359 impedance and, 33–34 negative, 104–105, 132 EDX study conclusion in, 361 RC circuit in, 37–39 ASFAPs. See apparent single fiber APs EMG study conclusion in, 335 steady state response of, 33 atomic number, 5 NCS in, 332–334, 359–361 time constant in, 22, 60 atomic structure, in charge, 4–5 needle EMG in, 334, 361 voltage in, 37 atoms, 4–5, 8 bilateral lower extremity weakness, capillaries, 66 ATP, 75–76 exercise, 428–429 cardiac injury, 291 ADP to, 78 NCS in, 429 carpal tunnel syndrome, 108, 126–127. of muscle fibers, 78 needle EMG in, 429–430 See also bilateral hand atypically proximal MGA, 267 bilateral upper extremity weakness, numbness and tingling AUC. See area under the curve exercise, 410, 421 concomitant, MGA with, 265–266 axolemma, 50, 53 EDX study conclusion in, 412 exercise, 324, 347, 351 axon, 50–51. See also distal; initial; NCS in, 410–411, 421–422 EDX impression in, 353–354 myelin; proximodistal needle EMG in, 411–412, EDX study conclusion in, 327, diameter, 62–63 422–424 349, 354 disruption biological signals, unwanted, 46 NCS in, 324–326, 347–348, 351–353 in NCS, 137–138 bipennate muscle, 80 needle EMG in, 325–327, 348, 353 Wallerian degeneration in, 137–138 biphasic morphology, 95–96 cathode, 11, 21–22, 42–43, 273–274 motor, 103, 201 bipolar recordings, 88 cauda equina, 241 terminals, 68 bits, 41 CDC. See Centers for Disease Control

514

Index

cell membrane, 49 clinical transient axonal, 131–132, 216 in EDX medicine, 49 bias, as pitfall, 285 conduction velocity, 62–64 electrophysiological properties of, features of forearm, 108, 126–127 49–50 of fasciculation potentials, 189 latency and, 132 ions of, 49–50 of lesions, 214 measurement of, 107–108 TMP and, 60 grading, of lesion severity, 215 nerve, 107 cells, 49, 52. See also anterior horn cells information, collected by EDX in proximal stimulation site, 108 electrochemical, 11 provider, 309 in sensory NCS, 114, 118–119 excitatory, 57 closed circuit, 14 time of, 107 Schwann, 52, 123, 131 CMAL. See chronic motor axon loss conductors, 8 Centers for Disease Control (CDC), 296 CMAP. See compound muscle action copper as, 10 central nervous system (CNS), 50–52, potential in flow, of charge, 10 76–77 CMRR. See common mode rejection metals as, 9 cervical plexus, 242 ratio cone, lateral surface area of, 180 change in distance, 107, 277 CNS. See central nervous system connective tissue, 65–66, 224 change in time, 34, 107, 277 coaxial cable, 31 conservation, of charge, 36 charge collateral sprouting, 183 constant current stimulators, 44, 272 atomic structure in, 4–5 motor response normalization constant voltage stimulators, 44, 272 in capacitors, 21–23 through, 132–133 consult. See also the encounter conductors, in flow of, 10 reinnervation via, 195–196, 201, reviewing, 307–308 conservation of, 36 218–220 scheduling, 308 current, as flow of, 8–10, 21, 43 common mode rejection ratio continuous conduction, 63 current, as movement of, 8 (CMRR), 47 continuous propagation, 61 in electricity, 4–8 common signal, 47 contractures, 189 electrostatic, 6–7 compartment syndrome, 232 conventional current, 9 negative, of electrons, 6 complete interference pattern, 196 cool limbs, studying separation, 22 complex repetitive discharges (CRDs), MUAP of, 260 separation, voltage and, 22 192–193 NCS of, 258–259 triboelectric effect in, 6 compound muscle action potential needle EMG for, 260 chassis current, 291–292 (CMAP), 95–96, 103–106 pitfalls of, 257–260 chemical denervation, 253 H wave as, 144 RNSS of, 259–260 chemical force, 54 median, 201 cooperative binding, 70 chemical synapses. See synapses SNAP and, 135 copper, 9–10 choline, 69. See also acetylcholine compression injuries, 228–229 correction factors, 259 choline acetyltransferase, 69 acute, 229–230 corticobulbar tract, 50 chronic compression, 230–231 chronic, 230–231 corticospinal tract, 50 chronic inflammatory demyelinating concentric needle electrodes, 206–207, Coulomb’s inverse-square law, 7 polyradiculoneuropathy 277 CPS. See cycles per second (CIDP), 249–250 concentric needle recording electrodes, cramp potentials, 188–190 chronic motor axon loss (CMAL), 320 179–180 CRDs. See complex repetitive chronodispersion, 147 conceptual pitfalls, 282–286 discharges CIDP. See chronic inflammatory conductance, 19 creatine kinase, 78 demyelinating conduction. See also demyelinating current. See also alternating current; polyradiculoneuropathy conduction block; direct current; Kirchhoff’s circuit demyelinating conduction current law breaker, main, 29 slowing; nerve; proximal; available, required, 125 closed, 14 saltatory conduction; transient capacitive, 21 DC in, 14, 33–34 axonal conduction block capacitors and, 20–23 EMF in, 13 antidromic, orthodromic, 92–93 chassis, 291–292 loop, 18 continuous, 63 conventional, 9 open, 14–15 ephaptic, 192–193 displacement, 21 parallel DC, 18–20 failure, axon loss and, 131–132 dividers, 19 resistance of, 15–16, 19–20 proximal, 147 in electricity, 8–10 series, 13–14 slowing, focal demyelinating, 126 electron, 9 series DC, 14–18 time, of muscle fibers, 107 as flow, of charge, 8–10, 21, 43 short, 15 values, 118 intensity of, 293–294 switches in, 15 volume, 90–92 leading source, 91 voltage in, 10, 17 conduction block, 216 let-go, can’t let-go, 291 clean signal, 46 pattern, of MGA, 267 limits, safe, 293

515

Index

current. (cont.) of membrane, 63 DMCS. See demyelinating conduction loop, 293 phase, 57 slowing as movement, of charge, 8 postsynaptic membrane, 71–72 doping, 42 Ohm’s law and, 15 repolarization and, 57–58 dorsal root ganglia (DRG), 51, pathway, 291 by stimulator, 43–44 133–134, 138, 140, 241 sources, 91–92 VGNCs in, 61 drift velocity, 9 stimulators and, 43–44 depolarization threshold, 54 duration, of MUAP. See motor unit trailing source, 91 desired signal, 33, 35, 45–46 action potential transmembrane, 60 diabetic neuropathic cachexia, 420–421 dysmyelinating disorders, 250–251 transverse, 62 difference, in signal, 46 cutaneous domain, 134 differential amplifiers, 45–47 E1 electrode. See also interelectrode cutoff frequency, 37, 39–40 differential signal, 87 distance cycles per second (CPS), 23 diffuse numbness and weakness, APs propagating toward, 102 cytoplasm, 50 exercise, 403–404 misplacement, in sensory NCS, 112 EDX conclusion in, 406–407 in motor NCS, 126 DAC. See digital-to-analog converter NCS in, 404–405 positive dip of, 97–98 dark matter, 4 needle EMG in, 405–406 in sensory NCS, 113 dB. See decibel diffuse upper extremity weakness and E2 electrode DC. See direct current sensory loss, exercise, 460 improper placement of, 97 decibel (dB), 26 EDX conclusion in, 463 in motor NCS, 126 decreased insertional activity, 184 NCS in, 460–461 needle for, 98 degeneration. See also Wallerian needle EMG in, 461–462 placement of, 96–97 degeneration digital filters, 41 in sensory NCS, 113 distal axon, 131 digital sensory NCS, 114 early recruitment, 169, 199–200 distal stump, 124 digital signal, 35 early repair, 231 of NMJ, 137 digital-to-analog converter (DAC), ECF. See extracellular fluid delayed repair, 231 41–43, 45 EDB. See extensor digitorum brevis demyelinating conduction block direct current (DC), 14. See also series EDX. See electrodiagnostic (DMCB), 123–125 DC circuits efflux, 54 acute compression and, 229–230 in circuit, 14, 33–34 Einthoven galvanometer, 85 amplitude discrepancy in, 130 circuits, parallel, 18–20 electric fields, 31 AUC and, 129 signal electric power axon loss and, 214 in capacitors, 38–39 single-phase, 28 chronic compression and, 230 danger of, 290–291 three-phase, 28–29 focal, 128–131, 202 discharge time, 125 electrical force, 54 lesion, 202 discrete interference pattern, 196 electrical injury MGA and, 263–264 disintegration, of motor unit, 169 general guidelines, to avoid, 293 neurapraxia and, 221–222 displacement current, 21 ground in, 292–293 proximal lesion and, 147 disposable gloves, 296–297 safety issues and, 290–293 proximally-located, 201 distal axon degeneration, 131 electricity spiral groove and, 128 distal axon sprouting. See collateral charge in, 4–8 stimulation sites, 130 sprouting current in, 8–10 ulnar motor response and, 129 distal latency in EDX, 3 demyelinating conduction slowing CMAP and, 105–106 history of, 4 (DMCS), 123–126, 214 measurement of, 105–106 household, 26–30 acute compression and, 229–230 time, 106–107 Ohm’s law in, 12–13 chronic compression and, 230 distal left upper extremity sensory and resistance in, 11–12 focal, 126–127, 202 motor abnormalities, exercise, static, 4 nonuniform, 127–128 442 as term, 4 proximal lesion and, 147–148 EDX study conclusion in, 445 voltage in, 10–11 uniform, 126–127 NCS in, 442–444 electrochemical cells, 11 demyelination, 123. See also acquired needle EMG in, 444–445 electrochemical force, gradient, 54 demyelinating distal muscles, 154 electrodes. See also E1 electrode; E2 polyneuropathies; focal distal sprouting, 220 electrode; motor NCS; needle demyelination distal stump, 134 electrode; needle recording focal, 123–126 distal stump degeneration, 124 electrodes; surface recording identifying, 284–285 distance, measurement of, 278–279 electrodes depolarization. See also endplate DMCB. See demyelinating conduction active, 87–88 potential block adhesive surface recording, 89

516

Index

ground, 46 dependent versus independent, 303 20:20 rule in, 100 history of, 86–87 explaining, to patient, 308–309 voltage in, 46 impedance and, 89, 270 findings of, 319 electromyography (EMG) machine inactive, 87–88 of focal neuropathies, 246–247 ADC, DAC in, 42 nonadhesive, 89 initial, 319 amplifier for, 45, 47 recording needle EMG in, 161–162 desired, undesired signal in, 33 APs and, 90–91 nerve fiber in, 52 isolated power systems and, 292 in sensory NCS, 115 preoperative versus postoperative, limitations of, 144 reference, 87 354 maximum stimulation in, 276 stimulating, 93–94 on radiculopathies, 240 onset, peak latency in, 117 surface stimulating, 88 reduced temperature in, 258–260 pitfalls of, 276 electrodiagnostic (EDX) abnormalities, signals in, 34–35 sensitivity of, 283 with nonorganic lesions, supervision of, 306–307 stimulator in, 44 318–319 timing of, 216 time cursors on, 285–286 electrodiagnostic (EDX) assessment variation, among EMG laboratories, on time difference, 277–278 issues, connective tissue and, 305 vertical resolution of, 283 224 electrodiagnostic (EDX) technique, electron current, 9 electrodiagnostic (EDX) examination RNS as, 152–153 electrons, 4–5 late responses in, 141 electrodiagnostic (EDX) testing, 33 capacitors and, 31 of plexopathies, 241–242 as extension, of neurological movement of, 8–9 sensory NCS in, 111 examination, 302 negatively charged, 6 timing of, 303–304 filters in, 34–35 Pauli exclusion principle and, 5–6 transmission, of infection in, 296 lesion localization in, 317–318 in static electricity, 7–8 electrodiagnostic (EDX) features limitations of, 304–305 electrostatic charge, 6–7 of axon loss, 248 for peripheral neuropathies, 246 electrostatic force, 31 of fasciculation potentials, 189–190 for polyneuropathies, 248 protons and, 7 of lesions, 214 of radiculopathies, 241 strength of, 7 of myotonic potentials, 191 for sensory neuronopathies, 251 electrotonic properties, 60 electrodiagnostic (EDX) grading, of utility of, 304 elements, 4 lesion severity, 215–216 electrolyte, 11 EMF. See electromotive force electrodiagnostic (EDX) laboratory electromagnetic field, 31 EMG. See electromyography negative AUC in, 105 electromagnetic induction, 23, 45 the encounter pathophysiology in, 105 electromagnetic radiation, 31 activities occurring after, 312 safety issues in, 290 electromagnetic waves, 9 activities occurring during electrodiagnostic (EDX) electromotive force (EMF), 10 limbs studied in, 309 manifestations, of myopathies, in circuit, 13 NCS performed first, 309 254 potential difference in, 10 needle EMG studies in, 309–312 electrodiagnostic (EDX) medicine voltage and, 12 activities occurring immediately APs in, 49 electromyography (EMG) before, 309 capacitors in, 20–21 abnormalities consult before cell membrane in, 49 APB and, 318 reviewing, 307–308 electricity in, 3 of FDI, 317 scheduling, 308 focal demyelination in, 124 disease, 170–171 verbal informed consent in, formulas in, 4 electromyography (EMG) laboratory. 308–309 voltage in, 10 See also needle EMG endoneurial tube, 65 electrodiagnostic (EDX) practitioner, antidromic sensory NCS in, 116 endoneurium, 65 skin preparation by, 44–45 EDX study variation among, 305 endplate, 68, 70. See also miniature electrodiagnostic (EDX) provider, 236 envelope pattern in, 154 endplate potential clinical information collected by, 309 F wave studies in, 148 activity, in needle EMG, 171 filters and, 34–35 facilitation in, 145 region, 95 in peripheral nerve injuries, 213 filters in, 41 spikes, 172 pitfalls of, 257, 270 H wave amplitude in, 144–145 endplate potential (EPP), 71–72. RC circuits and, 38 high frequency RNSS in, 157 See also miniature endplate electrodiagnostic (EDX) report, latency in, 116 potential 312–313 NCS in, 85, 93 end-to-end repair, 226 electrodiagnostic (EDX) studies. normal control values in, 282 end-to-end suturing, 226–227 See also consult; the encounter sensory NCS in, 113 envelope pattern, 154 components, order of performance standard, nonstandard motor NCS ephaptic conduction, 192–193 and, 305–306 in, 101 epineurial repair, 227

517

Index

epineurium, 65–66 spike form of, 185–186 cutoff, 37, 39–40 EPP. See endplate potential time to appearance of, 187 ideal sampling, 283 EPSPs. See excitatory postsynaptic filtering onset, 165–166 potentials high frequency, 280–281 recruitment of, 165–166 equilibrium potential, 55–56. See also issues, 279–281 frequency modulation (FM), 40 Nernst equation low frequency, 280 frequency-dependent resistors, 38 excessive stimulation, 275–276 in sensory NCS, 119–120 frequency-independent resistors, excitation-contraction coupling filters, 33 36 AP propagation in, 74 analog, 40–41 full interference pattern, 168 sarcomere in, 74–76 arrangements of, 40–41 fusimotor neurons, 76 sarcoplasmic reticulum in, 74 bandpass, 40 excitatory cells, 57 capacitors and, 34, 36 gain excitatory postsynaptic potentials cutoff frequency for, 39–40 on amplifiers, 44 (EPSPs), 61, 165 digital, 41 sensitivity and, 282 exhaustion, postexercise, 155–156 EDX providers and, 34–35 Galvani, Luigi, 9–10, 76 exocytosis, 69 in EMG laboratory, 41 galvanism, 9 extensor digitorum brevis (EDB), 285 high pass, 38, 40 gamma gain, 77 extracellular fluid (ECF), 53, 56–57 low pass, 38, 40 gases, 9 extrafusal muscle fiber innervation, 76 notch, 40–41 Gasser, Herbert, 62 extrafusal muscle fibers, 53 RC circuits in, 35–36 gated ion channels, 50, 54, 57–58 stopband, 40 gender, 262 F wave, 146 transition band in, 39 generalized low motor normal sensory APs of, 146 final common path, 76 (GLMNS), 138 latency, 146–148 firing frequency generalized weakness. See also diabetic minimal latency of, 147 of fibrillation potentials, 186–187 neuropathic cachexia physiology, technique of, 146–147 of motor units, 165 exercise, 415–416 repeater, 147 of MUAP, 165–168 diagnosis in, 420–421 studies, in EMG laboratories, 148 first dorsal interosseous (FDI) muscle NCS in, 416–418 utility of, 147–148 EMG abnormalities of, 317 needle EMG in, 418–420 facilitation MGA to, 264–267 GLMNS. See generalized low motor in EMG laboratory, 145 fixed distances, landmarks, 116–117 normal sensory postexercise, 155–156 flashover, 28 gloves, disposable, 296–297 farad, 22 flexor digitorum profundus (FDP), 317 Goldman-Hodgkin-Katz voltage fascicles, 65–66 flow equation, 56 fascicular repair, 227 of charge, 8–10, 21, 43 GRDs. See grouped repetitive fascicular sparing, 318 hole, 9 discharges fasciculation potentials, 188–189 ionic, 53–54, 56 grid, 27, 42 clinical features of, 189 of water, 12–14, 18–19 ground. See also iso-grounds EDX features of, 189–190 FM. See frequency modulation in electrical injury, 292–293 grading of, 190 focal axon loss, 124, 202 electrode, 46 myogenic, 189 focal demyelination, 123–124. See also loop current, 293 sites of origins of, 189 demyelinating conduction grouped repetitive discharges (GRDs), waveform morphology of, 189–190 slowing 192–193 FDA. See Food and Drug conduction, 126 Administration in NCS, 137–138 H band, 75 FDI. See first dorsal interosseous pathology of, 125–126 H reflex study, 142 muscle in sensory NCS, 134 supine patient in, 142 FDP. See flexor digitorum profundus focal DMCB, 128–131, 202 technique of, 142–143 fibrillation potentials, 185. See also focal DMCS, 126–127, 202 tibial nerve stimulation in, 142–144 needle EMG focal neuropathies, 246–247 H wave, 142 amplitude of, 185 Food and Drug Administration (FDA), amplitude duration, morphology of, 185–187 290 abnormal, 145 firing frequency of, 186–187 force generation, motor unit, 79 in EMG laboratory, 144–145 insertional positive sharp waves in, forearm latency measurements of, 144–145 188 anastomosis in, 268 as CMAP, 144 of myopathies, 254–255 conduction velocity, 108, 126–127 testing positive sharp wave form of, 186, 188 formulas, in EDX medicine, 4 technical errors in, 143–144 quantification of, 187 frequencies utility of, 145–146 specificity, utility of, 187–188 bandwidth of, 35 hand muscle innervation patterns, 269

518

Index

accessory deep peroneal nerve in, innervation. See also hand muscle concentric needle electrode for, 269–270 innervation patterns 206–207 Berretini anastomosis in, 269 anomalous, 262 potential, of muscle fiber APs, 205 head, 75 extrafusal muscle fiber, 76 value, of muscle fiber APs, Helmholtz, Herman von, 85 ratio, 51, 73, 195, 219 205–206 Henneman size principle, 164 zones, 103 juxtaparanode, 52 hereditary dysmyelination, 250–251 insertional activity hereditary polyneuropathies, 250–251 decreased, 184 Kennedy disease, 239 hertz (Hz), 23 increased, 184 Keraunoparalysis, 290 high frequency filtering, 280–281 in needle EMG, 162, 170–171, 184, Kirchhoff’s current law, 14–15, 36 high frequency RNSS. See repetitive 235 Kirchhoff’s voltage law, 14 nerve stimulation studies insertional positive sharp waves, 188 high pass filter, 38, 40 insulators, 8–9 Lambert test, 157–158 hinge, 75 intensity, of currents, 293–294 Lambert-Eaton myasthenic syndrome hole flow, 9 interconnections, 27 (LEMS) horizontal resolution, 283 interelectrode distance, in sensory background of, 253 household electricity, 26–30 NCS, 120–121 needle EMG study of, 253–254 hyperpolarization, 57–58 internal longitudinal current, 63 as NMJ disorder, 253–254 hypothenar eminence, MGA to, internal neurolysis, 231 RNSS for, 253 263–264 internodal distance, 63 routine NCS in, 253 Hz. See hertz internodal membrane segments, 63–64 late fibbers, 187 internodes, 52 late responses, in EDX examination, iatrogenic pneumothorax, 298–299 intervertebral foramina, 51 141 ICF. See intracellular fluid intracellular fluid (ICF), 53, 56–57 latency. See also onset latency ideal sampling frequencies, 283 intrafusal muscle fibers, 53, 76 conduction velocity and, 132 immediate release pool, 69 intraspinal canal disorders, 51 in EMG laboratories, 116 impedance, 23 acute poliomyelitis as, 237 of F wave, 146–148 in capacitors, 33–34 AHC disorders and, 236–237 measurements, of H wave, electrodes and, 89, 270 ALS as, 238 144–145 mismatch, 47, 270, 272 background anatomy of, 236 minimal, 147 between signal source, surface Kennedy disease as, 239 peak, 112, 117–118 recording electrode, 286 NCS in, 236 proximal, 105 skin, 273 post-poliomyelitis syndrome as, in sensory NCS, 116 inactivation gate, 258 237–238 values, 118 inactive electrode, 87–88. See also E2 radiculopathies as, 239–241 lateral surface area, of cone, 180 electrode SMA-3 as, 238–239 LCDD. See light-chain deposition incomplete interference pattern, intussusception, 214 disease 196–197 inverting amplifier, 46 lead-acid automotive battery, 11 increased insertional activity, 184 ion channels, 53–55 leading source current, 91 inductive coupling, 30 ionic current, 53–54 leading-off surface, 179 inductors, 23–24 ionic flow, 53–54 leading-off surface area, of needle indwelling medical devices ionic flux, 53–54 electrodes, 204 NCS with, 294–295 ionotropic receptors, 68 leadwire, 45–46 RNSS with, 295 ions, 8. See also Nernst equation least resistance, 18 safety issues of, 293–295 of cell membrane, 49–50 left common peroneal neuropathy, inert atoms, 8 flow of, 54, 56 376–378 infection, transmission of movement of, 56–57 left foot numbness and burning, disposable gloves, for preventing, IPSPs. See inhibitory postsynaptic exercise, 378 296–297 potentials EDX study conclusion in, 381 in EDX examination, 296 ischemic injuries, 231 NCS in, 378–380 needle electrodes in, 297–298 iso-grounds, 46 needle EMG in, 380–381 safety issues of, 296–298 isolated electrical myotonia, left hand atrophy, exercise, 457 skin in, 298 191 EDX conclusion in, 460 influx, 54 isolated power systems, 292 NCS in, 457–459 infraclavicular plexus, 243–244 isotopes, 5 needle EMG in, 459–460 inhibitory postsynaptic potentials isotropic bands, 75 left hip pain, exercise, 335 (IPSPs), 61 EMG conclusion in, 338 initial axon segment, 183 jiggle, 201, 206 NCS in, 335–337 initial positive phase, 91 jitter, 200, 205 needle EMG in, 337–338

519

Index

left upper extremity pain, tingling, and longitudinal tubules, 74 of conduction velocity, 107–108 weakness, exercise, 439 loop of distal latency, 105–106 EDX examination conclusion in, 442 circuit, 18 of distance, 278–279 NCS in, 439–441 current, 293 errors, 277–279, 285–286 needle EMG in, 441–442 recorder, 294 of motor response, 101–102 left wrist drop, exercise, 455 low frequency filtering, 280 MUAP, 164 EDX conclusion in, 457 low frequency RNSS. See repetitive of muscle fibers, 101–102 NCS in, 455–456 nerve stimulation studies needle EMG, 169–170 needle EMG in, 456–457 low pass filter, 38, 40 of negative AUC, 104–105 LEMS. See Lambert-Eaton myasthenic low voltage, 29 of negative phase duration, 109 syndrome lower back pain, exercise, 322, 367, 398 in sensory NCS, 112–113 length constant, 62, 125 EDX study conclusion in, 323, 370 medial brachial fascial compartment length-dependent polyneuropathies, EMG conclusion in, 400 (MBFC) syndrome, 478–479 247 NCS in, 322–323, 368, 398–399 median CMAP, 201 Lenz’s law, 23–24 needle EMG in, 323, 368–369, median-to-ulnar anastomosis, 262 lesion 399–400 Medical Research Council (MRC), 215 acuteness, 214–215 lower motor neurons (LMN), 50, 76 Medicare, 306 axon loss and, 215–216 lower plexus, 243–244 membrane, 54–55. See also ion clinical, EDX features of, 214 lumbosacral plexus channels; postsynaptic; completeness, 225–226 NCS of, 245 presynaptic; total membrane DMCB, 202 needle EMG study of, 245–246 capacitance; transmembrane localization plexopathies of, 245–246 current; transmembrane in EDX testing, 317–318 potential in NCS, 137, 140 M wave, 142, 276 capacitance of, 61–62 MUAP and, 202 machine maximum stimulation, 276 depolarization of, 63 nonorganic, 318–319 macro EMG, 204, 207–208 MEPP. See miniature endplate postganglionic, 140 macro MUAP, 208 potential proximal, 147–148 macroshock, 291 metals, as conductors, 9 in sensory NCS, 134 magnetic field, 26–28, 31 MGA. See Martin-Gruber anastomosis severity main circuit breaker, 29 microshock, 291 clinical grading of, 215 main reserve, 69 MIDD. See monoclonal EDX grading of, 215–216 maintenance of position, 235–236 immunoglobulin deposition motor response value and, major surgical interventions, 226–227 disease 217–218 Martin-Gruber anastomosis (MGA), middle plexus, 243–244 in needle EMG studies, 218 262–263. See also anastomosis miniature endplate potential (MEPP), sensory response value and, 218 to adductor pollicis muscle, 264–265 71, 152, 171–172 site, Wallerian degeneration at, atypically proximal, 267 minimal latency, of F waves, 147 137–138 with concomitant carpal tunnel missing relative abnormalities, 284 stimulation above, 131 syndrome, 265–266 mixed NCS, 93, 121–122 stimulation below, 131 with concomitant ulnar neuropathy, mixed polyneuropathies, 250 let-go currents, 291 266–267 mixed signal, 37–38 Leyden jar, 4 conduction block pattern of, 267 M-line, 75 ligand-gated channels, 54, 68 DMCB and, 263–264 MMV. See moment-to-moment light-chain deposition disease (LCDD), to FDI, 264–267 variability 397 to hypothenar eminence, 263–264 mobilization store, 69 lightning, 8 proximal median motor response molecules, amphiphilic, 49 limbs, studied, in NCS, 309. See also and, 266–267 moment-to-moment variability cool limbs, studying unrecognizable, 268 (MMV), 178, 200–201 linear phase characteristic, 40–41 mass number, 5 monoclonal immunoglobulin liquids, 9 maximal temporal recruitment, deposition disease (MIDD), LMN. See lower motor neurons 168–169 397 load, 15, 18 maximum response, to stimulus, 93 mononeuropathies. See focal local potentials, 61 MBFC. See medial brachial fascial monopolar amplifiers, 44–45 local responses, 59–61 compartment syndrome monopolar needle electrodes, 180 localization. See also lesion MCD. See mean consecutive difference motor axon point, 317 mean consecutive difference (MCD), amplitude of, 103 of postganglionic lesions, 140 205–207 loss, 201 regional, 317 measurement motor NCS, 85, 92, 95 long duration MUAPs, 248 of amplitude, 102–104 abbreviations for, 321

520

Index

advantages, disadvantages of, 132–133 lesions and, 202 studied, in needle EMG, 310 amplitude of, 100 long duration, 248 tissue transit time, 107 E1, E2 electrodes in, 126 macro, 208 tone, 77 exercise, for sensorimotor maximal temporal recruitment in, trapezius, 299 dysfunction, 354–355 168–169 unipennate, 80 focal demyelination and, 125–126 measurements, 164 muscle fiber APs, 74, 99, 102–103, 132, needle EMG and, 138–140, 161–162, MMV of, 178, 200–201 173–174 201 morphology, grading, 320 concentric needle electrodes for, nerve stimulation in, 98–99 muscle fiber APs and, 132 206–207 PNS elements assessed by, 138–140 of myopathies, 254 jitter value of, 205–206 proximal tibial motor response to, neurogenic, 130–131, 176, 218, jittering potential of, 205 100 243–245 SFEMG for, 204–205 radiculopathies and, 239–240 neurogenic recruitment in, 168–169, triggering potential of, 205 recording electrodes for, 95 197–198, 243–245 muscle fibers, 76 belly-tendon method and, 95–96 phases of, 177–178, 195 ATP of, 78 biphasic morphology of, 95–96 recording, 179–180 conduction time, 107 standard, nonstandard, 101 recruitment, 196–197 density of, 175–176 temporal dispersion and, 131 in ALS, 238 extrafusal, 53 motor nerve branching, 51 grading, 320 intermingling, 51 motor nerves, 85 in needle EMG, 165–166 intrafusal, 53, 76 motor neurons, 50–51, 146 pattern, 162, 169 measurement of, 101–102 motor point, of muscle, 95, 270–271 ratio of, 166–167 motor units of, 73, 78–79 motor response in UMN disorders, 235–236 NMJ of, 80 amplitude, 104, 135, 216 reinnervation via collateral sprouting primary, secondary endings in, 77 in blink reflexes, 149 in, 195–196 proximity of, 175–176 low, nonpathological causes of, 202 reinnervation via proximodistal axon types of, 79 measurement of, 101–102 advancement, 196 muscle-specific kinase (MuSK), 70 normalization, through collateral satellite potential and, 196 myasthenia gravis, 152 sprouting, 132–133 stability, 178, 200–201 AChR in, 252 from spinal cord level, 138 of trapezius muscle, 299 background of, 252 ulnar, 96–97, 129 trigger line of, 176 needle EMG study of, 253 value of, lesion severity and, 217–218 turns of, 177–178, 195 as NMJ disorder, 252–253 motor unit, 50, 124–125. See also non- voluntary activity in, 193–194 RNSS in, 252–253 myopathic motor unit movement routine NCS in, 252 disintegration disorders of charge, 8 myelin, 52–53. See also demyelination; AHC and, 79–80, 162–163 of electrons, 8–9 remyelination anatomy, physiology, 162–163 of ions, 56–57 advantage of, 61–62 disintegration disorders, 183 MRC. See Medical Research Council in AP propagation, 61–63 disintegration of, 169 MUAP. See motor unit action potential sheath, 123, 125 firing frequency of, 165 multipennate muscle, 80 myofibrils, 74 force generation, 79 muscle. See also first dorsal myogenic fasciculation potentials, 189 of muscle fibers, 73, 78–79 interosseous muscle; hand myokymia, 192–193 recruitment, 164–169 muscle innervation patterns; myopathies, 132, 199–200 size, distribution of, 79–80 neural control, of muscle EDX manifestations of, 254 types of, 78 activation time, 107 fibrillation potentials of, 254–255 motor unit action potential (MUAP), adductor pollicis, 264–265 MUAP of, 254 183 bipennate, 80 needle EMG and, 254 amplitude, 165, 173–176, 195 contraction, 78–79 myoplasm, 73 assessment distal, 154 myosin, 74–75 activation phase of, 193–194 innervation ratios, 51, 73, 219 myotome, spinal cord and, 138 in needle EMG, 162–163, 173, lengthening, 77 myotonia, 190–191. See also 183–184 motor point of, 95, 270–271 neuromyotonia auditory characteristics of, 161 multipennate, 80 myotonic potentials, 190–191 of cool limbs, 260 in needle EMG, 162 EDX features of, 191 duration, 163–164, 175–177, 194–195, shortening, 77–78 in needle EMG studies, 191 240, 261, 281–282, 284 spindles train of, 191 firing frequency of, 165–168 anatomy of, 77 full interference pattern in, 168 physiology of, 77–78 NA. See neuralgic amyotrophy GRD of, 192 structural organization of, 73–74 National Electrical Code, 29

521

Index

NCS. See nerve conduction studies for numbness, 402–403, 447–448 lessening discomfort associated neck pain, exercise, 349, 364, 370, for pacemaker placement, 454 with, 310–312 432–433 for peroneal neuropathy, 376 of lumbosacral plexus, 245–246 EDX study conclusion in, 373–374, for radiculopathies, 385–386 of myasthenia gravis, 253 390, 435–436 for right calf atrophy, 392–393 of plexopathies, 242–245 EMG conclusion in, 351, 367 for right foot drop, 331–332 in UMN disorders, 235 NCS in, 349–350, 364–366, 370–372, for right hand numbness, tingling, voluntary activity in, 162, 170, 173 387–389, 433–434 408–409 needle recording electrodes, 178–179 needle EMG in, 350–351, 366–367, for right upper extremity concentric, 179–180 372–373, 389–390, 434–435 weakness, 431–432 dimensions, areas of, 179 needle electrode, 98 for sciatic neuropathy, 343–347 monopolar, 180 concentric, 206–207, 277 for sensorimotor dysfunction, negative AUC jitter and, 206–207 356–359 amplitude and, 104–105, 132 leading-off surface dimensions of, for shoulder fracture-dislocation, in EDX laboratory, 105 204 328–329 measurement of, 104–105 macro EMG, 207–208 for symmetric weakness, 395–397, negative charge, of electrons, 6 monopolar, 180 413–415, 426–428 negative peak voltage, 25 recording surface, 277 for ulnar neuropathy, 341, 383 negative phase duration, 109 single-fiber, 204–205 for upper extremity weakness, negative sink, 91–92 in transmission, of infection, 297–298 wasting, 437–438 Nernst equation, 55–56 needle EMG. See also for weakness and numbness, nerve. See also sensory nerve action electromyography 450–451, 464–465, 467–468, potential abbreviations for, 321 470–471, 474–475, 477–478 accessory deep peroneal, 269–270 activation phase of, 173, 235 findings, range of, 320 activation time, 106 age-related issues in, 261 history of, 161 conduction bleeding in, 295–296 insertional activity in, 162, 170–171, time, 106–107 for cool limbs, 260 184, 235 velocity, 107 in EDX studies, 161–162 on Kennedy disease, 239 motor, 51, 85 endplate manifestations, of various preterminal, 242–243 activity in, 171 pathophysiologies, 202 transfer, 227 spikes in, 172 measurements, 169–170 trunk, 65–66, 228 exercise MEPP in, 171–172 nerve conduction studies (NCS). See for bilateral hand numbness, motor NCS and, 138–140, 161–162, also motor NCS; sensory NCS; tingling, 334, 361 201 surface recording electrodes for bilateral lower extremity MUAP abnormalities, 318 weakness, 429–430 assessment in, 162–163, 173 age-related issues in, 260–261 for bilateral upper extremity 183–184 axon disruption in, 137–138 weakness, 411–412, 422–424 duration in, 175–177, 284 bipolar, referential recordings of, for carpal tunnel syndrome, recruitment in, 165–166 88 325–327, 348, 353 stability in, 178 concepts, principles of, 85–86 for diffuse numbness, weakness, muscles in, 162, 310 of cool limbs, 258–259 405–406 myopathies and, 254 in EMG laboratory, 85, 93 for diffuse upper extremity myotonic potentials in, 191 exercise weakness, sensory loss, 461–462 pitfalls of, 281–282 for bilateral hand numbness, for distal left upper extremity provoked activity in, 170, 184 tingling, 332–334, 359–361 sensory, motor abnormalities, in radiculopathies, 240 for bilateral lower extremity 444–445 resting phase of, 171, 184–185 weakness, 429 for generalized weakness, 418–420 spontaneous activity in, 162, 170–171, for bilateral upper extremity for left foot numbness, burning, 184–185, 202 weakness, 410–411, 421–422 380–381 study for carpal tunnel syndrome, for left hand atrophy, 459–460 of axon loss, 215–216 324–326, 347–348, 351–353 for left hip pain, 337–338 of calcinosis cutis, 299 for diffuse numbness, weakness, for left upper extremity pain, in encounter, 309–312 404–405 tingling, weakness, 441–442 on hereditary polyneuropathies, for diffuse upper extremity for left wrist drop, 456–457 251 weakness, sensory loss, 460–461 for lower back pain, 323, 368–369, of iatrogenic pneumothorax, for distal left upper extremity 399–400 pneumoperitoneum, 298 sensory, motor abnormalities, for neck pain, 350–351, 366–367, of LEMS, 253–254 442–444 372–373, 389–390, 434–435 in lesion severity assessment, 218 for generalized weakness, 416–418

522

Index

for left foot numbness, burning, nerve fiber, 52–53, 99–100, 111. motor, 50–51, 146 378–380 See also fascicles; myelin resting, 57 for left hand atrophy, 457–459 nerve injuries sensory, 51–52 for left hip pain, 335–337 connective tissue in, 224 skeletofusimotor, 76 for left upper extremity pain, Seddon classification system for skeletomotor, 76 tingling, weakness, 439–441 axonotmesis in, 222 neurotization, 227 for left wrist drop, 455–456 neurapraxia in, 221–222 neurotmesis, 222 for lower back pain, 322–323, 368, neurotmesis in, 222 neurotonic discharge, 192 398–399 Sunderland classification system for, neurotransmitters, 68 for neck pain, 349–350, 364–366, 222 neutrons, 4–5 370–372, 387–389, 433–434 grade 1, 222 NMJ transmission time, 107 for numbness, 401–402, 445–447 grade 2, 222–223 NMJs. See neuromuscular junctions or bilateral lower extremity grade 3, 223 nodal intussusception, 230 weakness, 429 grade 4, 223 nodal membrane segments, 63–64 for pacemaker placement, grade 5, 223–224 nodes, of Ranvier, 52 452–454 grade 6, 224 noise, 35 for peroneal neuropathy, 374–375 surgical intervention in, 224–225 nonadhesive surface recording for radiculopathies, 384–385 types of, 227–228 electrodes, 89 for right calf atrophy, 391–392 compartment syndrome, 232 non-dissipative opposition, 23 for right foot drop, 330–331 compression injuries, 228–231 nongated ion channels, 54, 57–58 for right hand numbness, tingling, ischemic injuries, 231 non-inverting amplifiers, 46 407–408 stretch injuries, 228 nonlinear phase characteristic, 40–41 for right upper extremity traction injuries, 228 non-myopathic motor unit weakness, 431 transection injuries, 231 disintegration disorders, for sciatic neuropathy, 342–345 nerve stimulation 199–200 for sensorimotor dysfunction, in motor NCS, 98–99 nonorganic lesions, 318–319 355–356, 358 nonuniform DMCS and, 128 nonpathological causes, of low motor for shoulder fracture-dislocation, proximal median motor response to, responses, 202 327–328 99 nonuniform DMCS, 127–128 for symmetric weakness, 394–395, tibial, 142–144 normal control values, in EMG 412–413, 425–426 neural control, of muscle, 76 laboratory, 282 for ulnar neuropathy, 339–340, CNS influence in, 76–77 notch filter, 40–41 381–382 final common path in, 76 numbness. See also diffuse numbness for upper extremity weakness, muscle spindles in, 77 and weakness; left foot wasting, 436–437 neuralgic amyotrophy (NA), 439 numbness and burning; right for weakness and numbness, neurapraxia, 221–222 hand numbness and tingling; 448–450, 463–464, 466–467, neurogenic MUAP, 130–131, 176, 218, weakness and numbness 469–470, 472–477 243–245 exercise, 400, 445 explaining, to patient, 308–309 neurogenic recruitment EDX conclusion in, 403, 448 findings of, 319 grades of, 320 NCS in, 401–402, 445–447 focal demyelination in, 137–138 grading, 197–198 needle EMG in, 402–403, 447–448 focal DMCB and, 129 MUAP in, 168–169, 197–198 focal DMCS, 126 243–245 Occupational Safety and Health with indwelling medical devices, as pathological, 319 Administration (OSHA), 290, 294–295 neurological examination, 302 296 in intraspinal canal disorders, 236 neuromuscular junctions (NMJ), 68–71 Ohm, Georg Simon, 12 in lesion localization, 137, 140 degeneration, 137 Ohm’s law limbs studied in, 309 disorders, 152, 251–252 on AC, 23 of lumbosacral plexus, 245 LEMS as, 253–254 current and, 15 manifestations, timing of, 135–136 myasthenia gravis as, 252–253 in electricity, 12–13 mixed, 93, 121–122 in high frequency RNSS, 157 reactance, resistance and, 33 performed first, during encounter, of muscle fibers, 80 voltage and, 15 309 transmission, 200, 205 onset frequency, 165–166 pitfalls of, 281 disorders, SFEMG for, 206 onset latency, 105–106, 112 routine, in LEMS, 253 safety factor of, 153 changing sensitivity, to better routine, in myasthenia gravis, 252 neuromyotonia, 191–192 identify, 282–283 surface recording electrodes in, 87 neuronopathies, sensory, 251 peak latency and, 117–118 technician, 306 neurons, 50 in SNAP, 116 in UMN, 235 fusimotor, 76 open circuit, 14–15

523

Index

orthodromic conduction, 92–93 clinical biases as, 285 primary endings, in muscle fibers, orthodromic sensory NCS, 111, conceptual, 282–286 77 114–116 of EDX providers, 257, 270 primary synaptic cleft, 70 OSHA. See Occupational Safety and of EMG machine, 276 progressive proximal spinal and bulbar Health Administration impedance, between signal source, muscular atrophy. See Kennedy output voltage, 17 surface recording electrode as, disease 286 propagation. See also action potential paced fiber, 193 of NCS, 281 propagation pacemaker placement, exercise, 452 of needle EMG, 281–282 bidirectional, 74 EDX conclusion in, 454 of recording electrodes, 270–271 continuous, 61 NCS in, 452–454 of stimulation, 271–281 protons, 4–5, 7 needle EMG in, 454 studying cool limbs, 257–260 provoked activity, in needle EMG, 170, pacing fiber, 193 technical, 270 184 parallel circuits, 13–14 time constraints as, 284 proximal conduction time, 147 parallel DC circuits, 18–20 plexopathies proximal latency, 105 parallel resistors, 19–20 of brachial plexus, 242–245 proximal lesion, 147–148 pathophysiology, 105, 133–134, 202, of cervical plexus, 242 proximal median motor response 214–215 EDX examination of, 241–242 MGA and, 266–267 Pauli exclusion principle, 5–6 of lumbosacral plexus, 245–246 to nerve stimulation, 99 peak latency, 112, 117–118 needle EMG studies of, 242–245 proximal stimulation site, 108, 111–112 peak voltage, 25, 37 neurogenic MUAP in, 243–245 proximal tibial motor response, to peak-to-peak sensory NCS in, 241–242 motor NCS, 100 amplitude, 113, 173–175 pneumoperitoneum, 298–299 proximally-located DMCB, 201 voltage, 25 PNS. See peripheral nervous system proximodistal axon advancement, 183, pennate muscle, 80 point localization, 317 196, 220 perineurium, 65 polyneuropathies proximodistal axon regeneration, period, of wave, 24–25 acquired axon loss, 247–248 219–220 peripheral nerve injuries acquired demyelinating, 248–249 pseudofacilitation, 155–157 demographics of, 213 AIDP as, 249 proper initial management of, 213 CIDP as, 249–250 quantal content, 69, 71 types of, 213 EDX testing for, 248 quantification, of fibrillation potentials, peripheral nervous system (PNS), hereditary, 250–251 187 50–52, 138–140 length-dependent, 247 quantum, 69 peripheral neuropathies mixed, 250 quarks, 5 acquired axon loss polyneuropathies sensory NCS in, 248 as, 247–248 positive dip, of E1 electrode, 97–98, radiculopathies, 134. See also neck pain EDX testing for, 246 270–271 EDX study of, 240 focal, 246–247 positive sharp wave form EDX testing of, 241 types of, 246 of fibrillation potential, 186, 188 exercise peroneal neuropathy. See also accessory insertional, 188 NCS in, 384–385 deep peroneal nerve postexercise exhaustion, 155–156 needle EMG in, 385–386 deep, 364 postexercise facilitation, 155–156 as intraspinal canal disorders, exercise, 361–363, 374 postganglionic lesions, 140 239–241 EDX conclusions of, 364, 376–378 post-poliomyelitis syndrome, 237–238 motor NCS and, 239–240 NCS in, 374–375 postsynaptic folds, 70 MUAP duration in, 240 needle EMG in, 376 postsynaptic membrane, 68 needle EMG in, 240 left common, 376–378 postsynaptic membrane raindrops striking a tin roof, right superficial, 364 depolarizations, 71–72 186–187 peroneal-EDB, 285 postsynaptic region, 70–71 rapsyn, 70 phases, of MUAP, 177–178, 195 potential difference, 10 RC circuits phosphocreatine, 78 power loss equation, 29–30 capacitors in, 37–39 phospholipid layers, 49 power stroke, 75 EDX providers and, 38 photons, 7, 9 preamplifier, 87 filters in, 35–36 physiologic temporal dispersion, precautions, of OSHA, 296 mixed signal in, 37–38 113–114, 131 prepatterning, 70 RCA. See Riche-Cannieu anastomosis Piper, H., 85 presynaptic membrane, 68 reactance, 23 pitfalls presynaptic region, 69 capacitive, 36 age-related issues, 260–261 preterminal nerves, of brachial plexus, Ohm’s law and, 33 body habitus-related issues, 261–262 242–243 reciprocals, 19

524

Index

recording electrodes. See also abnormal, 156 NCS in, 431 electrodes; motor NCS; needle baseline train in, 154 needle EMG in, 431–432 recording electrodes; surface distal muscles in, 154 rigor mortis, 76 recording electrodes postexercise facilitation, RMP. See resting membrane potential APs of, 90–91 exhaustion in, 155–156 RMS. See root-mean-square voltage for MUAP, 179–180 pseudofacilitation in, 155–156 value pitfalls of, 270–271 technical errors in, 156–157 RNS. See repetitive nerve stimulation in sensory NCS, 115 technique of, 154–155 RNSS. See repetitive nerve stimulation recruitment. See also motor unit action for myasthenia gravis, 252–253 studies potential; neurogenic repolarization roll-off slope, 39 recruitment absolute, relative refractory period root-mean-square (RMS) voltage value, early, 169, 199–200 in, 58–59 25–26 frequency, 165–166 depolarization and, 57–58 Rule of 20, 225 maximal temporal, 168–169 phase, 57 rule of fives, in recruitment ratio, 166–167 motor unit, 164–169 resistance, 23 ratio, 166, 168 amplifier, 44 safe current limits, 293 full interference pattern in, 168 of circuit, 15–16, 19–20 safety factor, 71 rule of fives in, 166–167 in electricity, 11–12 of AP propagation, 125–126 spatial, temporal, 169, 198–199 least, 18 of NMJ transmission, 153 UMN, 198–199 Ohm’s law and, 33 safety issues red flags, 248 of skin, 44, 293 of bleeding, 295–296 reduced interference pattern, 197 of tissue, 291 of calcinosis cutis, 299 reduced temperature, in EDX study, total membrane, 60 in EDX laboratory, 290 258–260 voltage and, 15–16, 18 electrical injury and, 290–293 reference electrode, 87 resistors, 15–17. See also RC circuit of iatrogenic pneumothorax, referential recordings, 88 frequency-dependent, 38 pneumoperitoneum, 298–299 regenerative distance, 225–226 frequency-independent, 36 of indwelling medical devices, regional localization, 317 parallel, 19–20 293–295 reinnervation, 183, 194–195 response dispersion, 109 of transmission, of infection, aberrant, 223 resting membrane potential (RMP), 43, 296–298 via collateral sprouting, 195–196, 55–56 saltatory conduction, 61, 63–64, 201, 218–220 resting neuron, 57 123 determining potential for, 220–221 resting phase, of needle EMG, 171, sarcolemma, 73–74 mechanisms of, 218, 220 184–185 sarcomeres, 74 via proximodistal axon reversals sarcoplasm, 73 advancement, 196, 220 in AC, 23, 36 sarcoplasmic reticulum, 74 via proximodistal axon regeneration, stimulator, 279 satellite potential, MUAP and, 196 219–220 ribbon pair leadwire, 46 Schwann cells, 52, 123–124, 131 sensory receptor, 220 Riche-Cannieu anastomosis (RCA), sciatic neuropathy. See also right foot relative refractory period, 58–59 268–269 drop relatively abnormal, 284 right calf atrophy, exercise, 390 exercise, 342 Remak bundle, 52 EDX study conclusion in, 394 EDX study conclusion in, 344 remyelination, 221 NCS in, 391–392 NCS in, 342–345 repeater F waves, 147 needle EMG for, 392–393 needle EMG in, 343–347 repetitive nerve stimulation (RNS), right foot drop, exercise, 329–330 secondary clefts, 70 152–153 EDX study conclusion in, secondary endings, in muscle fibers, repetitive nerve stimulation studies 332 77 (RNSS), 152–153 NCS in, 330–331 Seddon classification system of cool limbs, 259–260 needle EMG in, 331–332 axonotmesis in, 222 high frequency, 157 right hand numbness and tingling, neurapraxia in, 221–222 in EMG laboratories, 157 exercise, 407 neurotmesis in, 222 Lambert test in, 157–158 EDX study conclusion in, 409 selective ionic permeability, 53, 56 in NMJ transmission disorders, NCS in, 407–408 semiconductors, 8–9 157 needle EMG in, 408–409 sensitivity pseudofacilitation in, 157 right superficial peroneal neuropathy, changing, to better identify onset technique, 157–158 364 latency, 282–283 with indwelling medical devices, 295 right upper extremity weakness, of EMG machines, 283 for LEMS, 253 exercise, 430–431 gain and, 282 low frequency, 153 EDX study conclusion in, 432 sweep speed and, 283–284

525

Index

sensorimotor dysfunction, exercise, 354 common, 47 pitfalls of, 271–281 EDX study conclusion in, 357 desired, undesired, in EMG machine, sites motor NCS in, 354–355 33 of DMCB, 130 NCS in, 355–356, 358 difference, 46 proximal, 108, 111–112 needle EMG in, 356–359 in EDX study, 34–35 submaximal, 274–275, 279 sensory domains, 134 mixed, 37–38 stimulators sensory NCS, 92–93 source, 286 constant current, 44, 272 abbreviations for, 320–321 signal source generator, 46 constant voltage, 44, 272 advantages, disadvantages of, 119, signal-to-noise ratio (SNR), 35, 47, 277 current and, 43–44 135 silent contractures, 184 depolarization by, 43–44 amplitude in, 113–114 single fiber EMG (SFEMG), 204, 207–208 on EMG machines, 44 antidromic, orthodromic, 111, criteria, for assessment, 206 reversal of, 279 114–116 for muscle fiber APs, 204–205 skin resistance to, 44 conduction velocity in, 114, 118–119 needle electrodes, 204–205 stimulus. See also nerve stimulation digital, 114 for NMJ transmission disorders, 206 lead, 89, 93, 276 in DRG, 138 utility of, 206 maximum response to, 93 E1, E2 electrodes in, 113 single-phase power, 28 spread, 276 E1 electrode misplacement in, 112 sink, 91–92 strength, 89–90, 93 in EDX examination, 111 sixth-degree injury, 224 supramaximal, 93 in EMG laboratories, 113 60 Hz power artifact, AC signal of, stimulus artifact, 271–272 filtering in, 119–120 276–278 reduction, 272–273 focal demyelination in, 134 skeletofusimotor neurons, 76 anode rotation, about cathode in, interelectrode distance in, 120–121 skeletomotor neurons, 76 273–275 latency in, 116 skin final options in, 274 lesions in, 134 impedance, 273 future of, 274 in localization, of postganglionic preparation, 44–45, 88–89 stopband filter, 40. See also notch filter lesions, 140 resistance, 44, 293 stretch injuries, 228 manifestations, of pathology, in transmission, of infection, 298 submaximal stimulation, 274–275, pathophysiology, 133–134 SMA-3. See spinal muscular atrophy 279 measurement in, 112–113 type 3 Sunderland classification system, in plexopathies, 241–242 SNAP. See sensory nerve action 222–223, 225–226 on PNS, 139–140 potential grade 1, 222 in polyneuropathies, 248 snap-crackle-pop, 170 grade 2, 222–223 proximal stimulation site in, SNR. See signal-to-noise ratio grade 3, 223 111–112 solid angle analysis, 92 grade 4, 223 recording electrodes in, 115 spatial recruitment, 169, 198–199 grade 5, 223–224 technique, 111–112 spike form, of fibrillation potential, grade 6, 224 sensory nerve action potential (SNAP), 185–186 supervision, of EDX study, 306–307 111, 116, 135 spinal cord supine patient, in H reflex study, sensory nerve fibers, 52–53, 111 level, motor response from, 138 142 sensory neuronopathies, 251 myotome and, 138 supraclavicular plexus, 243 sensory neurons, 51–52 spinal muscular atrophy type 3 supramaximal stimulus, 93 sensory receptor reinnervation, 220 (SMA-3), 238–239 surface recording electrodes sensory response spiral groove, DMCB and, 128 adhesive, nonadhesive, 89 amplitude, 135, 216 spontaneous activity, in needle EMG, basic technique of, 88–90 axon loss and, 135–136 162, 170–171, 184–185, 202 impedance, between signal source value of, lesion severity and, 218 standard precautions, 296 and, 286 series circuits, 13–14 staphylococcus aureus, 298 in NCS, 87 series DC circuits, 14–18 static, 6 proper placement of, 87–88 SFEMG. See single fiber EMG static electricity, 4, 7–8 response to, 89–90 shock artifact. See stimulus steady state, 33 surface stimulating electrodes, 88 short circuit, 15 stimulating electrodes, 93–94 surgical intervention shoulder fracture-dislocation, exercise, stimulation. See also nerve stimulation; approach, to axon loss in, 225–226 327 repetitive nerve stimulation in nerve injuries, 224–225 EDX study conclusion in, 329 studies surgical interventions, major, 226–227 NCS in, 327–328 above lesion, 131 suturing, end-to-end, 226–227 needle EMG in, 328–329 below lesion, 131 sweep speed, 283–284 signal excessive, 275–276 switches, 15 clean, 46 machine maximum, 276 switchyards, 27

526

Index

symmetric weakness, exercise, 394, 412, trailing source current, 91 recruitment, 198–199 424–425 transection injuries, 231 upper plexus, 243–244 NCS in, 394–395, 412–413, 425–426 transformers, 27–31 needle EMG in, 395–397, 413–415, transient axonal conduction block, vacuum tube, 42 426–428 131–132, 216 velocity. See conduction velocity; drift synapses, 68 transistor batteries, 11 velocity synaptic space, 68–69 transition band, 39 verbal informed consent, 308–309 synchronized slowing. See uniform transmembrane current, 60 vertical resolution, 42–43, 283 DMCS transmembrane potential (TMP), 43, vesicles, of ACh, 69, 71–72, 152–153 synchrony, 103 53, 185. See also resting VGCCs. See voltage-gated calcium synthesized ACh, 69 membrane potential channels cell membrane and, 60 VGKCs. See voltage-gated potassium tail, 75 equilibrium potential and, 55–56 channels technical errors ion movement and, 56 VGNCs. See voltage-gated sodium in H wave testing, 143–144 of resting neuron, 57 channels in low frequency RNSS, 156–157 transmission feeders, 27 voltage. See also constant voltage temporal dispersion transverse current, 62 stimulators; direct current; motor NCS and, 131 transverse tubules, 74 Goldman-Hodgkin-Katz physiologic, 99–100, 113–114, 131 trapezius muscle, 299 voltage equation; Kirchhoff’s temporal recruitment, 169, 198–199 triad, 74 voltage law; root-mean-square terminal boutons, 68–69 triboelectric effect, 6 voltage value terminal branch conduction time, trigger line, of MUAP, 176 in AC, 23–24 107 triggering potential, of muscle fiber in batteries, 10–11, 18 terminal cisternae, 74 APs, 205 in capacitors, 37 terminal positive phase, 91 tropomyosin, 74–75 charge separation and, 22 territorial distribution, 51 troponin, 74–75 in circuit, 10, 17 thick filaments, 75–76 turns, of MUAP, 177–178, 195 dividers, as resistors, 16–17 thin filaments, 75–76 20:20 rule, 100 in EDX medicine, 10 three-phase power, 28–29 twisted pair leadwire, 46 in electricity, 10–11 threshold time, 106 EMF and, 12 tibial nerve stimulation, in H reflex ulnar motor response, 96–97, 129 in EMG laboratory, 46 study, 142–144 ulnar neuropathy, 263, 266–267. low, ultrahigh, 29 tibial response, amplitude, 100 See also neck pain negative peak, 25 time exercise, 338, 381 Ohm’s law and, 15 backfire, 146–147 EDX study conclusion in, output, 17 of conduction velocity, 107 341–342, 383–384 peak, 25, 37 constant NCS in, 339–340, 381–382 peak-to-peak, 25 in capacitors, 22, 60 needle EMG in, 341, 383 resistance and, 15–16, 18 myelin sheath and, 125 ulnar-to-median anastomosis, 268 ultrahigh, 29 constraints, as pitfalls, 284 ultrahigh voltage, 29 voltage-gated calcium channels cursors, on EMG machines, 285–286 UMN. See upper motor neuron (VGCCs), 68, 253 difference, 277–278 undesired signal, 33, 35, 45–46. See also voltage-gated channels, 54 discharge, 125 noise voltage-gated potassium channels distal latency and, 106–107 uniform DMCS, 126–127 (VGKCs), 54, 58 of muscle activation, 107 unipennate muscle, 80 voltage-gated sodium channels of nerve activation, 106 universal precautions, 296 (VGNCs), 54, 58–59 of NMJ transmission, 107 upper extremity weakness and wasting, activation gate of, 258 of proximal conduction, 147 exercise, 436 in bidirectional propagation, 74 of terminal branch conduction, 107 EDX study conclusion in, 439 in depolarization, 61 threshold, 106 NCS in, 436–437 volume conduction, 90–92 tissue transit, 106 needle EMG in, 437–438 voluntary activity tissue upper motor neuron (UMN), 50, 76. in MUAP assessment, 193–194 resistance of, 291 See also intraspinal canal in needle EMG, 162, 170, 173 transit time, 106 disorders TMP. See transmembrane potential ALS and, 238 Wallerian degeneration, 123–124, 131, total membrane capacitance, 60 disorders, 235–236 134 total membrane resistance, 60 MUAP recruitment in, 235–236 in axon disruption, 137–138 tourniquet paralysis, 230 NCS in, 235 conduction block in, 216 traction injuries, 228 needle EMG in, 235 at lesion site, 137–138

527

Index

water, flow of, 12–14, weakness and numbness, exercise, 448, Weichers-Johnson syndrome, 18–19 463, 465, 468, 472, 475 170–171 wave, period of, 24–25 EDX conclusion in, 451–452, 465, weight, 262 weakness. See bilateral lower extremity 468, 471–472, 475, 478 weakness; bilateral upper NCS in, 448–450, 463–464, 466–467, X-linked recessive bulbospinal extremity weakness; generalized 469–470, 472–477 neuronopathy, 239 weakness; symmetric weakness; needle EMG in, 450–451, 464–465, upper extremity weakness and 467–468, 470–471, 474–475, zinc-carbon batteries, 11 wasting 477–478 Z-line, 75

528