Transcutaneous Electrical Nerve Stimulation (TENS) Review

Comprehensive practice flashcards covering concepts, parameters, mechanisms, safety precautions, and clinical application rules for Transcutaneous Electrical Nerve Stimulation (TENS).

What is Transcutaneous Electrical Nerve Stimulation (TENS)?

TENS is a method of pain relief that uses mild electrical current to apply stimulation to superficial sensory nerves, influencing pain-emanating signals detected by the spinal cord and brain.

What is the maximum current output delivered by most TENS machines?

Most TENS machines deliver up to $100\text{ mA}$.

What are the two main proposed mechanisms behind TENS pain relief?

The pain gate theory and the opioid release theory.

How does the pain gate theory operate during TENS treatment?

It excites A beta sensory fibers to decrease the transmission of noxious stimuli from A delta and C fibers to the spinal cord and brain.

What frequency range is typically used to achieve pain relief via the pain gate theory?

Higher frequencies between $90\text{ Hz}$ and $130\text{ Hz}$.

How does the opioid release mechanism of TENS work?

It stimulates A delta fibers to trigger the release of natural pain-relieving opiates (enkephalins and endorphins) from the spine, decreasing noxious sensory pathway activation.

What frequency setting is required to induce an opioid release effect?

Lower frequencies, typically between $2\text{ Hz}$ and $5\text{ Hz}$.

What sensitivity test is used before applying TENS, and what tool is used for it?

A sharp and blunt test using an examination pin called a neuro tip.

At what error threshold during a sharp and blunt test is TENS considered a precaution?

If the patient is incorrect on more than $3$ occasions.

What three prescription parameters can be manipulated on a TENS unit?

Intensity, pulse width, and frequency.

What are the typical settings, target, and duration for conventional (high) TENS?

Conventional TENS targets general pain relief using high frequencies ($90\text{--}130\text{ Hz}$), narrower pulse width starting at $100$, a definite (not uncomfortable) intensity, and lasts $20\text{ to }30\text{ minutes}$.

What are the key parameters and target for acupuncture (low) TENS?

Acupuncture TENS targets muscle pain using low frequencies ($2\text{--}5\text{ Hz}$), wider pulse width (up to $250$), a strong intensity sensation, and treatment for at least $30\text{ minutes}$.

How does burst TENS function differently from standard conventional TENS?

Burst TENS applies identical frequency, pulse width, intensity, and duration, but delivers $2\text{ to }3$ bursts at a time to increase the effect on the pain gate theory.

What is the clinical purpose of using modulated TENS?

Modulated TENS changes the pattern of signal delivery to prevent the body from adapting to a repeatedly applied stimulus.

What required elements must be included in clinical record notation for TENS treatment?

Number of electrodes ($2$ or $4$ pole application), exact position, frequency, pulse width, intensity (numerical rating or patient reported sensation), and treatment duration in minutes.