TEN ENS S therapy metho d : TENS is the acronym acronym of Transcutaneous Transcutaneous Electrical Nerve Stimulation ,is is a modality modality that uses surface electrodes to deliver a pulsed electrical current through the skin to sitmulate nerves for the purpose of controlling and relieving pain (fig.17.1). the word ‘’transcutaneous’’ ‘’transcu taneous’’ means through the skin,and ‘’nerve timulation’’ refers to the current having enough intensity to depolarize sensory nerves. nerv es.
TABLE 17.1
KEY PARAMETERS FOR TENS modality
Current type
AC
Wave form
Biphasic
Total current flow
1-100 mA
frequency
1-150 Hz(pps)
Elecrode placement
Directly on pain ,dermatome,motor points,trigger points,acupuncture points,acupuncture poiints,nerve root,contiguous,contralateral root,contiguous,contralateral
Primary indication
Acute and chronic pain
THE PHYSÄ°OLOGÄ°CAL EFFECT OF TENS the physiological effect of TENS is selective depolarization of afferent nerves. Electrodes are placed on the skin ,usually at the site of the pain. By B y adjusting different parameters on a TENS unit, the clinician can change the patient’s perception of acute and chronic pain.
TENS MODES There are three major modes of tens,each applied by modulating the intensity and beat frequency (adjustable pulses per second): 1- Sensory TENS: used to treat acute pain by stimulating large-diameter large -diameter sensory nerves. The heat frequency is high (80-200 pps), and the intensity inten sity is adjusted to the point where the patient reports a buzzing or tingling. tingl ing. This is conventional or traditional TENS. 2- Motor TENS: used to treat chronic pain by stimulating small-diameter afferent nerves. The beat frequency is low (1-5 pps),and the intensity is higher than sensory TENS (to the patient’s tolerance). The patient reports some burning,needling sensation,and a slight muscle twitch. 3- Brief-intense TENS:used to treat chronic pain prior to rehabilitaion by stimulating C fibers. The beat frequency varies between low and high and changes periodically. The intensity is also higher than sensory TENS(to the patient’s tolerance). The patient reports some burning,needling sensation, and twitch and tetanic muscle contractions.
The stimulation benefits in pain relief and increases the level of endorphin hormones in the body, which promotes a feeling of wellness and helps in relieving the pains .. So,this method use as an analgesic effect .. TENS relieves pain associated with osteoarthritis,rheumatoid osteoarthritis,rheumatoid arthritis,dysmenorhea, and low-back pain.
How the Tens Units blocks the pain signal ? The TENS unit electrodes are taped to the body part that is in pain. For example, if you are having pain in your neck, specifically in the trapezius muscle- you would place the electrode on the trapezius muscle. muscle. There are two types of nerve fibers that come into play: large nerve fibers, and small nerve fibers. Pain signals travels along small nerve fibers. The large nerve fibers are also knows as the nociceptive fibers fiber s because they do not tranmit pain. The electrode tranmits electrical current along these fibers. The tens units works by preventing these small nerve fibers from reaching the brain by stimulating the large nerve fibers. fibers. The large nerve fibers "close the gate" in the spinal cord, thus giving pain relief. This is the basis of the "gate control theory of pain" whereby called nonnociceptive fibers can fibers can interfere with signals from pain fibers, thereby inhibiting pain.
This type of therapeutic method is also use in strengthening the Proprioception senses to help the sicks who suffers suffers from the joint pains which caused by the the degeneration joints… loss of normal joint motion (loss of proprioception) causes degeneration of the affected joint. Furthermore, it tells us that degeneration of the joint causes loss of normal joint motion (loss of proprioception). Be aware that “degeneration” “degeneration” of joints used to be called Degenerative Arthritis or Osteoarthritis. And with the TENS therapy method we can remove these problems !!!!…… TENS may be able to reduce pain and muscle spasms caused spasms caused by a wide range of conditions, including:
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pain back pain sports injuries injuries pain period pain pain knee pain neck pain pain