This lecture provides an overview of transcutaneous electrical nerve stimulation (TENS) therapy. TENS involves using electric currents to stimulate nerves for pain relief. It works by activating the body's pain gate mechanism or endogenous opioid system. There are different types of TENS machines and techniques depending on factors like frequency and pulse width. Proper electrode placement is also important for targeting specific nerves or areas. TENS is generally safe but should not be used by people with certain medical conditions or over some parts of the body.

1. Transcutaneous Electrical Nerve
Stimulation Lecture
Presented by Andrea Eugrafia

2. TOPIC OUTLINE
● Introduction
● TENS Mechanism of action
● Types of TENS machine
● Types of TENS Techniques
● Machine parameters
● Electrode placement
● Contraindication and Precautions

3. What is TENS?
TENS is a method of electrical stimulation which primarily aims to
provide a degree of symptomatic pain relief by exciting sensory nerves
and thereby stimulating either the pain gate mechanism or the opioid
system
Research literature supports that it is better used in home-
based patient delivery therapy than in the clinic.

4. What is TENS?
● Non-invasive
● Commonly delivered from small hand
held battery powered devices
● Primarily indicated for chronic pain and
acute pain

5. Mechanism of
Action
Pain Gate Control
Theory
(Melzack & Wall 1965)

6. Mechanism of
Action
Pain Gate Control
Theory
(Melzack & Wall 1965)

7. Mechanism of
Action
Pain Gate Control
Theory
(Melzack & Wall 1965)

8. Mechanism of
Action
Endogenous Opioid
System
Periaqueductal grey matter + Raphe Nucleus
Substantia Gelatinosa
=
Inhibition of pain transmission

9. Types of TENS Machine
Analogue
TENS devices
Digital
TENS devices
Maternity
TENS devices

10. Types of TENS Machine
Multimodal device which includes
TENS
Garment based
TENS devices

11. Machine Parameters
Treatment Variables:
A. Current Intensity : 0-80mA
B. Pulse Rate or Frequency: 2-150 Hz or pps
(pulse per second)
C. Pulse Width: 40-250 μs
- Most effective setting is around 200 μs
A. Dual Channel Output
- Widespread or diffused pain: 4 electrode
(2 channel)
A. Duration

12. Types of TENS Techniques
1. Conventional/High TENS
● Uses high frequency stimulation
● Patient should feel “strong but
comfortable” tingling sensation.
● Most effective during intervention and
provides limited “carry over” effect.
Frequency: 100-150 Hz
PW: 200 μs
Duration:30 minutes
NOTE: Muscle twitching should not occu
2. Acupuncture/Low TENS
● Uses low frequency stimulation with
longer pulse rate
● Patient should feel “definite, strong
sensation” that is almost painful
● Onset of pain relief may be slower
● Carry over effect may last over several
hours
Frequency: 1-5 Hz
PW: 1-150 μs
Duration:30 minutes

13. Types of TENS Techniques
3. Brief Intense TENS
● Indicated to achieve rapid pain relief
● Uses high pulse frequency and width
● Current is delivered at or close to pt’s
tolerance level
Frequency: 80-130 Hz
PW: 200 μs
Duration: 15-30 minutes
4. Burst Mode TENS
● Able to stimulate both pain gate and
opioid mechanism
● Same settings with conventional but
with the addition of Burst Mode
Frequency: 1-5 Hz
PW: 1-150 μs
Duration:30 minutes

14. Types of TENS Techniques
5. Modulation Mode TENS
● delivers less regular pulse output which
minimizes accommodation effects
● Indicated for patients who use TENS for
hours a day
● Less intensity adjustment is required
Frequency and PW: Varies from different
machines

15. Electrode Placement
Target:
● Appropriate nerve root
● Appropriate dermatome and
myotome
● Peripheral nerve proximal to pain
area
● Motor point
● Trigger points
● Acupuncture points
● Each side of the lesion or pain area
NOTE:
● 2 Channel application may be
effective for a local and referred pain
combo
● Acupuncture TENS can be effectively
applied to the C/L side of the body

16. Contraindications and Precautions
CONTRAINDICATIONS
● Pts who cannot comprehend instructions
or unable to operate the machine
● Application over the trunk, abdomen or
pelvis during pregnancy
● Presence of cardiac pacemaker
● Allergy to the electrodes or gel
● Open wounds dermatitis, eczema
● Application over carotid sinus or anterior
of neck
PRECAUTIONS:
● Abnormal skin sensation
● Application over eyes
● Patients with epilepsy
● Avoid epiphyseal regions in children

17. THANK YOU!
References:
● Forster, A., Palastanga, N., & Clayton, E. B.
(2005). Clayton's electrotherapy: Theory &
practice. New Delhi: CBS.
● Sluka, K. A., & Walsh, D. (2003).
Transcutaneous electrical nerve
stimulation: Basic science mechanisms
and clinical effectiveness. The Journal of
Pain, 4(3), 109–121.
doi:10.1054/jpai.2003.434
● Gibson, W., Wand, B. M., & O’Connell, N. E.
(2017). Transcutaneous electrical nerve
stimulation (TENS) for neuropathic pain in
adults. Cochrane Database of Systematic
● Watson, T. (2016). Transcutaneous
electrical nerve Stimulation (TENS).
Retrieved March 03, 2021, from
http://www.electrotherapy.org/modality/tr
anscutaneous-electrical-nerve-stimulation-
tens