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electromyography (emg)
Presenter: Sana Rai  (MPT 1st Year) 
Guide: Dr. Suvarna Ganvir (PhD)
Department of Neurophysiotherapy
D.V.V.P.F’s College of Physiotherapy, Ahmednagar
Objectives 
• Introduction
• Concepts of EMG
• Different types of electrodes. 
• Clinical EMG.
1. Normal potential
2. Abnormal potential.
• EMG findings in different conditions.
• Clinical implication.
• Summary 
• Reference 
Introduction 
• Electromyography tests the integrity of the entire motor 
system,  which  consists  of  upper  and  lower  motor 
neurons, the neuromuscular junction, and muscle.
• Electromyography (EMG) is used to evaluate the scope 
of neuromuscular disease or trauma, and kinesiological 
electromyography is used to study muscle function.
• As  the  examination  procedure,  clinical  EMG  involves  the 
detection and recording of electrical potentials from skeletal 
muscles fibers.
• Electromyographer must first learn physiologic mechanisms of 
normal  muscle  contraction  to  understand  the  various 
abnormalities that characterize disorders of the motor system.
• Multiple factors affect the outcome of recordings. 
1. age of patients.
2. the particular properties of the muscle under study.
3. the  electrical  specifications  of  the  needle  electrodes  and 
recording apparatus.
Concepts of Electromyography 
• EMG is the recording of the electrical activity 
of muscles and in essence, the study of motor 
unit activity.
• The single axon conducts an impulse to all its 
muscle  fibers,  causing  them  to  depolarize  at 
relatively the same time.
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• This  depolarization  produces  electrical  activity  that  is 
manifested  as  a  motor  unit  action  potential  (MUAP)  and 
recorded and displayed graphically as the EMG signal. 
• Instrumentation  for  recording  EMG  potentials  requires  a 
3phase system:
1. An input phase: electrode       electrical potentials from 
contracting muscles.
2. Processor phase: small electrical signal is amplified.
3. Output phase: electrical signal          visual/ audible  signal
Instrumentation and Signal 
Characteristics
Ø Detecting the EMG signals: Electrodes
• An electrode is a transducer ; a device for converting one 
form of energy into another.
• Types of electrodes:
1. Surface electrodes.
2. Fine wire indwelling electrodes.
3. Needle electrode.
4. Ground electrode.
• Surface  Electrode  are  used  frequently  when 
performing  a  NCV  test  and  in  some  kinesological 
investigation. 
• They  are  generally  considered  adequate  for 
monitoring large superficial muscle or muscle group.
• The simplest surface EMG electrode is a small metal 
disc, commonly made of silver/ silver chloride, which 
is typically 3 to 5 mm in diameter.
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• Fine  Wire  Indwelling  Electrode  were  introduced  in 
the early 1960 for kinesiological study of small and 
deep muscle.
• Fine  wire  electrodes  are  necessary  for  monitoring 
activity  from  deep  muscles,  such  as  the  soleus,  or 
small or narrow muscle , such as the fingers flexors.
• They mat not be as useful for large muscles because 
they  sample  motor  unit  activity  form  such  a  small 
area of the muscle.
• They  are  inappropriate  for  use  in  clinical  EMG 
because  the  examiner  has  either  good  control  over 
placement of the electrode, nor the ability to move the 
electrode within the muscle once it is placed.
• Ultrasound imaging has recently been used with great 
success in helping to guide the placement of fine wire 
electrodes  in  deeply  situation  muscles,  such  as  the 
iliopsoas.
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• A Needle Electrode is required for clinical EMG, so 
that single motor unit potentials can be recorded from 
difference parts of a muscle.
• The  1st  studies  of  motor  unit  activity  were  done  in 
1929  by  Adrian  and  Bronk  who  used  a  concentric 
needle electrode.
• The bare tip of the platinum wire is considered to be 
the  active  electrode  and  the  cannula  acts  as  the 
reference electrode.
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• Another commonly used approach for clinical EMG 
involves  the  use  of  a  Monopolar  Needle  Electrode, 
which is composed of a single fine needle, insulated 
except at the tip.
• These  electrodes  are  less  painful  than  concentric 
electrodes because they are smaller in diameter.
• Monopolar  configurations  record  much  larger 
potentials than bipolar.
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• In  addition  to  a  recording  electrode  (either  surface  or 
needle), a ground electrode must be applied to provide a 
mechanism  for canceling  out the interference  effect of 
external  electrical  noise  such  as  that  caused  by 
fluorescent lights, broadcasting facilities, elevators and 
other electrical apparatus.
• The  Ground  Electrode  is  a  surface  electrode  that  is 
attached  to  the  skin  near  the  recording  electrodes,  but 
usually not over muscle.
Clinical EMG 
• The  EMG  Examination:  testing  usually  involves 
observation of muscle action potentials form several 
muscles in different stages of muscle contraction.
• The  EMG  signals  is  only  part  of  a  complete 
examination, however which will include a thorough 
understanding  of  the  patients  history  and  clinical 
findings.
• Insertional  Activity:  initially,  the  patient  is  asked  to 
relax the muscle to be examined during insertion of the 
needle electrode.
• At  this  time,  a  spontaneous  burst  of  potentials  is 
observed,  which  is  possibly  caused  by  the  needle 
breaking through muscle fiber membranes.
• This is called insertional activity and normally lasts less 
than 300msec.
• Insertional activity can be describe as normal, reduced, 
absent, increased, or prolonged.
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• The Muscle At Rest: following cessation of insertional 
activity, a normal relaxed muscle will exhibit electrical 
silence, which is the absence of electrical potentials.
• It is often difficult for the patient to relax sufficiently to 
observe complete electrical silence.
• However, the potential seen will be distinct motor unit 
potential,  whereas  spontaneous  potential  can  be 
differentiated by their distinct characteristics related to 
amplitude, shape, frequency, waveform and sound.
• Normal Motor Unit Action Potential: after observing 
the muscle at rest, the patient is asked to contract the 
muscle minimally.
• This  weak  voluntary  effort  should  cause  individual 
motor unit to fire.
• These motor unit potential are examined with respect 
to amplitude, duration, shape, sound, and frequency.
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Abnormal potential
• Spontaneous Activity: a normal muscle at rest exhibits 
electrical  silence,  any  activity  seen  during  the  relaxed 
state can be considered abnormal.
• Such activity is termed as spontaneous because it is not 
produced by voluntary muscle contraction.
• 4  types  of  spontaneous  potentials  have  been 
identified:
1. Fibrillation potential.
2. Positive sharp waves.
3. Fasciculation potential.
4. Repetitive discharge.
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Positive Sharp Waves Myotonic And Complex
Repetitive Discharge
It is observed in denervated muscle 
at rest 
lesion of the anterior horn cell and 
peripheral nerves , and with 
myopathies.
Biphasic waves . Regular and repetitive waveform.
Amplitude:  50µV to 2mV
Frequency: 2 to 100 per sec
Duration: 100 msec
Amplitude: : 50µV to 1mV
Frequency: 50 to 100 per sec
Duration: 100 msec 
Muscle dystrophy and polymyositis.  Myotonic dystrophy as well as 
other myopathies
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Different conditions 
• Amyotrophic lateral sclerosis: It is  motor neuron disease (MND), 
is a specific disease which cause death of the neurons controlling 
voluntary muscle.
• Muscle dystrophy: It  is a group of muscle diseases that results in 
increasing  weakening  and  breakdown  of skeletal  muscles over 
time.
Electrodiagnosis in Amyotrophic Lateral Sclerosis
Nanette C Joyce, D.O., M.A.S.1 and Gregory T Carter, M.D., M.S.
PM R. 2013 May; 5(5 0): S89–S95.
For the evaluation of LMN findings in ALS, the clinical and electrophysiological 
abnormalities have equal diagnostic significance in any given body region.
However, two EMG features are required for confirmation of neurogenic change 
consistent with a diagnosis of ALS:
1.              Evidence of chronic neurogenic change.
2.              Evidence of acute denervation.
To support a diagnosis of ALS, the needle electrode examination should reveal 
decreased motor unit recruitment with rapid firing of a reduced number of motor 
units, and/or large amplitude, long duration  MUP  with or without evidence of 
remodeling (increased number of phases) in combination with abnormal 
spontaneous activity including positive sharp waves (PSWs), fibrillations, and/or 
fasciculation potentials (FP). 
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Electrophysiology of Myopathy Approach to the Patient With
Myopathy in the EMG Laboratory
Nithi S. Anand and David Chad
•  An  increase  in  insertional  activity  is  the  first  EMG  clue  to  the  presence  of 
abnormal spontaneous potentials in the muscle.
• The four abnormal spontaneous potentials to look for in a patient with myopathy 
comprise:  fibrillation  potentials,  positive  sharp  waves  (PSWs),  myotonic 
potentials, and complex repetitive discharges (CRDs).
• Fibrillation potentials are the most common abnormal insertional/spontaneous 
activity observed in myopathies. 
•They  seem  to  arise  spontaneously  from  either  a  single  muscle  fiber  or  a  few 
muscle fibers and are not associated with visible contractions. They are biphasic 
or triphasic waves with an initial positive deflection. They are usually 1 to 2 ms in 
duration and less than 100 µV in amplitude.
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Clinical Implication 
Assessment of Low Back Muscle by Surface EMG
Adalgiso Coscrato Cardozo and Mauro Gonçalves
• Introduction : Surface electromyography (EMG) is wide used to 
analyze back muscle activity.
•  This tool is a non-invasive technique that allows the evaluation of 
muscle activity.
• The aim of the chapter is to provide a global understand of EMG 
parameters used to access low back muscle.
• Low back muscle fatigue during isometric contractions: Dolan 
et al. (1995) developed an alternative protocol called “Frequency 
Banding. 
• In  their  study  thirty-five  health  volunteers  pulled  upward  with 
constant force on a handlebar attached to the floor while the EMG 
signal from the erector spinae was recorded at the levels T10 and 
L3. 
• The power spectra were divided into 10 frequency bands between 
5Hz and 300Hz.
• Conclusion:  EMG  techniques  and  its  application  to 
the assessment of low back muscle.
•   It  was  shown  that  the  surface  EMG  has  a  good 
reliability  in  its  parameters,  and  is  a  good  tool  to 
access muscle fatigue.
The clinical significance of electromyography normalisation
techniques in subjects with anterior cruciate ligament injury
during treadmill walking.
Benoit DL1, Lamontagne M, Cerulli G, Liti A.
Gait Posture.2003 Oct; 18(2):56-63.
Abstract:
• This study investigated the clinical interpretation of three electromyographic 
(EMG)  normalisation  techniques  to  detect  neuromuscular  alterations  in 
patients diagnosed with anterior cruciate ligament knee injury during treadmill 
walking. 
• The EMG signal was normalised using the mean value during the gait cycles 
(MEA), the maximum value during the gait cycles (MAX), and a maximum 
voluntary isometric contraction (MVC) test in 16 male and female subjects.
• The MAX method detected an increase in total muscle activity in 
the  injured  limb  rectus  femoris  (11.6%;  P=0.02)  while  the  MVC 
method  detected  decreased  injured  limb  gastrocnemius  medialis 
(GM) overall muscle activity (34.4%; P=0.02). The MAX method 
identified decreased GM activity in three portions of the gait cycle.
• This study indicates the importance of choosing the appropriate 
normalisation  technique  since  its  choice  will  change  outcome 
measures and subsequent clinical interpretation.
The Effects of Upper-Limb Training Assisted with an
Electromyography-Driven Neuromuscular Electrical
Stimulation Robotic Hand on Chronic Stroke
Chingyi Nam,1 Wei Rong,1 Waiming Li,1 Yunong Xie,1 Xiaoling 
Hu,1,* and Yongping Zheng1
Background:
Impaired hand dexterity is a major disability of the upper limb after stroke. An 
electromyography (EMG)-driven neuromuscular electrical stimulation (NMES) 
robotic hand was designed previously, whereas its rehabilitation effects were not 
investigated.
Method:
A  clinical  trial  with  single-group  design  was  conducted  on  chronic  stroke 
participants (n = 15) who received 20 sessions of EMG-driven NMES-robotic 
hand-assisted upper-limb training. 
The  training  effects  were  evaluated  by  pre  training,  post  training,  and  3-month 
follow-up  assessments  with  the  clinical  scores  of  the  Fugl-Meyer  Assessment 
(FMA), the Action Research Arm Test (ARAT), the Wolf Motor Function Test, the 
Motor  Functional  Independence  Measure,  and  the  Modified  Ashworth  Scale 
(MAS).  Improvements  in  the  muscle  coordination  across  the  sessions  were 
investigated  by  EMG  parameters,  including  EMG  activation  level  and  Co-
contraction Indexes (CIs) of the target muscles in the upper limb.
Conclusion:
The  upper-limb  training  integrated  with  the  assistance  from  the  EMG-driven 
NMES-robotic  hand  is  effective  for  the  improvements  of  the  voluntary  motor 
functions  and  the  muscle  coordination  in  the  proximal  and  distal  joints. 
Furthermore,  the  motor  improvement  after  the  training  could  be  maintained  till 
3 months later.
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Summary
• Introduction
• Concepts of EMG
• Instrumentation and signal characteristics.
1. Different types of electrodes. 
2. EMG examination.
3. Normal potential.
4. Abnormal potential.
• Different conditions 
• Clinical implication.
References
1. Physical  Rehabilitation  5th  Edition.  By:  Susan  B.O’sullivan. 
Thomas J. Schmitz.
2.  Electrodiagnosis in Diseases of Nerve And Muscle: Principles 
and Practice. By: Jun Kimura
3. Electrodiagnosis  in  Amyotrophic  Lateral  Sclerosis,  Nanette  C 
Joyce et al, PM R. 2013 May; 5(5 0): S89–S95.
4. Electrophysiology of Myopathy Approach to the Patient With 
Myopathy in the EMG Laboratory , Nithi S. Anand et al.
5.  The  clinical  significance  of  electromyography  normalisation 
techniques  in  subjects  with  anterior  cruciate  ligament  injury 
during treadmill walking. Benoit dl et al. Gait posture. 2003 oct; 
18(2):56-63.
6. The effects of upper-limb training assisted with an  neuromuscular 
electrical  stimulation  robotic  hand  on  chronic  stroke.  Chingyi 
Nam et al. 
7. Applications of EMG in clinical and sports medicine : Edited by 
Catriona Steele.
thank
you

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Emg

  • 2. Objectives  • Introduction • Concepts of EMG • Different types of electrodes.  • Clinical EMG. 1. Normal potential 2. Abnormal potential. • EMG findings in different conditions. • Clinical implication. • Summary  • Reference 
  • 3. Introduction  • Electromyography tests the integrity of the entire motor  system,  which  consists  of  upper  and  lower  motor  neurons, the neuromuscular junction, and muscle. • Electromyography (EMG) is used to evaluate the scope  of neuromuscular disease or trauma, and kinesiological  electromyography is used to study muscle function.
  • 4. • As  the  examination  procedure,  clinical  EMG  involves  the  detection and recording of electrical potentials from skeletal  muscles fibers. • Electromyographer must first learn physiologic mechanisms of  normal  muscle  contraction  to  understand  the  various  abnormalities that characterize disorders of the motor system. • Multiple factors affect the outcome of recordings.  1. age of patients. 2. the particular properties of the muscle under study. 3. the  electrical  specifications  of  the  needle  electrodes  and  recording apparatus.
  • 7. • This  depolarization  produces  electrical  activity  that  is  manifested  as  a  motor  unit  action  potential  (MUAP)  and  recorded and displayed graphically as the EMG signal.  • Instrumentation  for  recording  EMG  potentials  requires  a  3phase system: 1. An input phase: electrode       electrical potentials from  contracting muscles. 2. Processor phase: small electrical signal is amplified. 3. Output phase: electrical signal          visual/ audible  signal
  • 9. • Surface  Electrode  are  used  frequently  when  performing  a  NCV  test  and  in  some  kinesological  investigation.  • They  are  generally  considered  adequate  for  monitoring large superficial muscle or muscle group. • The simplest surface EMG electrode is a small metal  disc, commonly made of silver/ silver chloride, which  is typically 3 to 5 mm in diameter.
  • 14. • Fine  Wire  Indwelling  Electrode  were  introduced  in  the early 1960 for kinesiological study of small and  deep muscle. • Fine  wire  electrodes  are  necessary  for  monitoring  activity  from  deep  muscles,  such  as  the  soleus,  or  small or narrow muscle , such as the fingers flexors. • They mat not be as useful for large muscles because  they  sample  motor  unit  activity  form  such  a  small  area of the muscle.
  • 15. • They  are  inappropriate  for  use  in  clinical  EMG  because  the  examiner  has  either  good  control  over  placement of the electrode, nor the ability to move the  electrode within the muscle once it is placed. • Ultrasound imaging has recently been used with great  success in helping to guide the placement of fine wire  electrodes  in  deeply  situation  muscles,  such  as  the  iliopsoas.
  • 17. • A Needle Electrode is required for clinical EMG, so  that single motor unit potentials can be recorded from  difference parts of a muscle. • The  1st  studies  of  motor  unit  activity  were  done  in  1929  by  Adrian  and  Bronk  who  used  a  concentric  needle electrode. • The bare tip of the platinum wire is considered to be  the  active  electrode  and  the  cannula  acts  as  the  reference electrode.
  • 19. • Another commonly used approach for clinical EMG  involves  the  use  of  a  Monopolar  Needle  Electrode,  which is composed of a single fine needle, insulated  except at the tip. • These  electrodes  are  less  painful  than  concentric  electrodes because they are smaller in diameter. • Monopolar  configurations  record  much  larger  potentials than bipolar.
  • 21. • In  addition  to  a  recording  electrode  (either  surface  or  needle), a ground electrode must be applied to provide a  mechanism  for canceling  out the interference  effect of  external  electrical  noise  such  as  that  caused  by  fluorescent lights, broadcasting facilities, elevators and  other electrical apparatus. • The  Ground  Electrode  is  a  surface  electrode  that  is  attached  to  the  skin  near  the  recording  electrodes,  but  usually not over muscle.
  • 22. Clinical EMG  • The  EMG  Examination:  testing  usually  involves  observation of muscle action potentials form several  muscles in different stages of muscle contraction. • The  EMG  signals  is  only  part  of  a  complete  examination, however which will include a thorough  understanding  of  the  patients  history  and  clinical  findings.
  • 23. • Insertional  Activity:  initially,  the  patient  is  asked  to  relax the muscle to be examined during insertion of the  needle electrode. • At  this  time,  a  spontaneous  burst  of  potentials  is  observed,  which  is  possibly  caused  by  the  needle  breaking through muscle fiber membranes. • This is called insertional activity and normally lasts less  than 300msec. • Insertional activity can be describe as normal, reduced,  absent, increased, or prolonged.
  • 25. • The Muscle At Rest: following cessation of insertional  activity, a normal relaxed muscle will exhibit electrical  silence, which is the absence of electrical potentials. • It is often difficult for the patient to relax sufficiently to  observe complete electrical silence. • However, the potential seen will be distinct motor unit  potential,  whereas  spontaneous  potential  can  be  differentiated by their distinct characteristics related to  amplitude, shape, frequency, waveform and sound.
  • 26. • Normal Motor Unit Action Potential: after observing  the muscle at rest, the patient is asked to contract the  muscle minimally. • This  weak  voluntary  effort  should  cause  individual  motor unit to fire. • These motor unit potential are examined with respect  to amplitude, duration, shape, sound, and frequency.
  • 29. Abnormal potential • Spontaneous Activity: a normal muscle at rest exhibits  electrical  silence,  any  activity  seen  during  the  relaxed  state can be considered abnormal. • Such activity is termed as spontaneous because it is not  produced by voluntary muscle contraction.
  • 30. • 4  types  of  spontaneous  potentials  have  been  identified: 1. Fibrillation potential. 2. Positive sharp waves. 3. Fasciculation potential. 4. Repetitive discharge.
  • 32. Positive Sharp Waves Myotonic And Complex Repetitive Discharge It is observed in denervated muscle  at rest  lesion of the anterior horn cell and  peripheral nerves , and with  myopathies. Biphasic waves . Regular and repetitive waveform. Amplitude:  50µV to 2mV Frequency: 2 to 100 per sec Duration: 100 msec Amplitude: : 50µV to 1mV Frequency: 50 to 100 per sec Duration: 100 msec  Muscle dystrophy and polymyositis.  Myotonic dystrophy as well as  other myopathies
  • 36. Electrodiagnosis in Amyotrophic Lateral Sclerosis Nanette C Joyce, D.O., M.A.S.1 and Gregory T Carter, M.D., M.S. PM R. 2013 May; 5(5 0): S89–S95. For the evaluation of LMN findings in ALS, the clinical and electrophysiological  abnormalities have equal diagnostic significance in any given body region. However, two EMG features are required for confirmation of neurogenic change  consistent with a diagnosis of ALS: 1.              Evidence of chronic neurogenic change. 2.              Evidence of acute denervation. To support a diagnosis of ALS, the needle electrode examination should reveal  decreased motor unit recruitment with rapid firing of a reduced number of motor  units, and/or large amplitude, long duration  MUP  with or without evidence of  remodeling (increased number of phases) in combination with abnormal  spontaneous activity including positive sharp waves (PSWs), fibrillations, and/or  fasciculation potentials (FP). 
  • 38. Electrophysiology of Myopathy Approach to the Patient With Myopathy in the EMG Laboratory Nithi S. Anand and David Chad •  An  increase  in  insertional  activity  is  the  first  EMG  clue  to  the  presence  of  abnormal spontaneous potentials in the muscle. • The four abnormal spontaneous potentials to look for in a patient with myopathy  comprise:  fibrillation  potentials,  positive  sharp  waves  (PSWs),  myotonic  potentials, and complex repetitive discharges (CRDs). • Fibrillation potentials are the most common abnormal insertional/spontaneous  activity observed in myopathies.  •They  seem  to  arise  spontaneously  from  either  a  single  muscle  fiber  or  a  few  muscle fibers and are not associated with visible contractions. They are biphasic  or triphasic waves with an initial positive deflection. They are usually 1 to 2 ms in  duration and less than 100 µV in amplitude.
  • 40. Clinical Implication  Assessment of Low Back Muscle by Surface EMG Adalgiso Coscrato Cardozo and Mauro Gonçalves • Introduction : Surface electromyography (EMG) is wide used to  analyze back muscle activity. •  This tool is a non-invasive technique that allows the evaluation of  muscle activity. • The aim of the chapter is to provide a global understand of EMG  parameters used to access low back muscle.
  • 41. • Low back muscle fatigue during isometric contractions: Dolan  et al. (1995) developed an alternative protocol called “Frequency  Banding.  • In  their  study  thirty-five  health  volunteers  pulled  upward  with  constant force on a handlebar attached to the floor while the EMG  signal from the erector spinae was recorded at the levels T10 and  L3.  • The power spectra were divided into 10 frequency bands between  5Hz and 300Hz.
  • 42. • Conclusion:  EMG  techniques  and  its  application  to  the assessment of low back muscle. •   It  was  shown  that  the  surface  EMG  has  a  good  reliability  in  its  parameters,  and  is  a  good  tool  to  access muscle fatigue.
  • 43. The clinical significance of electromyography normalisation techniques in subjects with anterior cruciate ligament injury during treadmill walking. Benoit DL1, Lamontagne M, Cerulli G, Liti A. Gait Posture.2003 Oct; 18(2):56-63. Abstract: • This study investigated the clinical interpretation of three electromyographic  (EMG)  normalisation  techniques  to  detect  neuromuscular  alterations  in  patients diagnosed with anterior cruciate ligament knee injury during treadmill  walking.  • The EMG signal was normalised using the mean value during the gait cycles  (MEA), the maximum value during the gait cycles (MAX), and a maximum  voluntary isometric contraction (MVC) test in 16 male and female subjects.
  • 44. • The MAX method detected an increase in total muscle activity in  the  injured  limb  rectus  femoris  (11.6%;  P=0.02)  while  the  MVC  method  detected  decreased  injured  limb  gastrocnemius  medialis  (GM) overall muscle activity (34.4%; P=0.02). The MAX method  identified decreased GM activity in three portions of the gait cycle. • This study indicates the importance of choosing the appropriate  normalisation  technique  since  its  choice  will  change  outcome  measures and subsequent clinical interpretation.
  • 45. The Effects of Upper-Limb Training Assisted with an Electromyography-Driven Neuromuscular Electrical Stimulation Robotic Hand on Chronic Stroke Chingyi Nam,1 Wei Rong,1 Waiming Li,1 Yunong Xie,1 Xiaoling  Hu,1,* and Yongping Zheng1 Background: Impaired hand dexterity is a major disability of the upper limb after stroke. An  electromyography (EMG)-driven neuromuscular electrical stimulation (NMES)  robotic hand was designed previously, whereas its rehabilitation effects were not  investigated. Method: A  clinical  trial  with  single-group  design  was  conducted  on  chronic  stroke  participants (n = 15) who received 20 sessions of EMG-driven NMES-robotic  hand-assisted upper-limb training. 
  • 46. The  training  effects  were  evaluated  by  pre  training,  post  training,  and  3-month  follow-up  assessments  with  the  clinical  scores  of  the  Fugl-Meyer  Assessment  (FMA), the Action Research Arm Test (ARAT), the Wolf Motor Function Test, the  Motor  Functional  Independence  Measure,  and  the  Modified  Ashworth  Scale  (MAS).  Improvements  in  the  muscle  coordination  across  the  sessions  were  investigated  by  EMG  parameters,  including  EMG  activation  level  and  Co- contraction Indexes (CIs) of the target muscles in the upper limb. Conclusion: The  upper-limb  training  integrated  with  the  assistance  from  the  EMG-driven  NMES-robotic  hand  is  effective  for  the  improvements  of  the  voluntary  motor  functions  and  the  muscle  coordination  in  the  proximal  and  distal  joints.  Furthermore,  the  motor  improvement  after  the  training  could  be  maintained  till  3 months later.
  • 48. Summary • Introduction • Concepts of EMG • Instrumentation and signal characteristics. 1. Different types of electrodes.  2. EMG examination. 3. Normal potential. 4. Abnormal potential. • Different conditions  • Clinical implication.
  • 49. References 1. Physical  Rehabilitation  5th  Edition.  By:  Susan  B.O’sullivan.  Thomas J. Schmitz. 2.  Electrodiagnosis in Diseases of Nerve And Muscle: Principles  and Practice. By: Jun Kimura 3. Electrodiagnosis  in  Amyotrophic  Lateral  Sclerosis,  Nanette  C  Joyce et al, PM R. 2013 May; 5(5 0): S89–S95. 4. Electrophysiology of Myopathy Approach to the Patient With  Myopathy in the EMG Laboratory , Nithi S. Anand et al.
  • 50. 5.  The  clinical  significance  of  electromyography  normalisation  techniques  in  subjects  with  anterior  cruciate  ligament  injury  during treadmill walking. Benoit dl et al. Gait posture. 2003 oct;  18(2):56-63. 6. The effects of upper-limb training assisted with an  neuromuscular  electrical  stimulation  robotic  hand  on  chronic  stroke.  Chingyi  Nam et al.  7. Applications of EMG in clinical and sports medicine : Edited by  Catriona Steele.