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1.2 Medical Background
1.2.1 About Pain
Pain is an important signal in the human body warning
system. It reminds us that something is wrong without
which abnormal conditions may go undetected, causing
damage or injury to vital parts of our bodies. Even
though pain is a necessary warning signal of trauma or
malfunction in the body, nature may have gone too far in its
design. Aside from its function in diagnosis, long-lasting
persistent pain is not useful to its original purpose.
Pain does not occur until an encoded message travels to
the brain where it is decoded, analyzed, and reacted to
from the injured area along the small nerves leading to the
spinal cord. There the message is transmitted to different
nerves that travel up the spinal cord to the brain. Then the
pain message is interpreted, referred to, and pain is felt.
1.2.2 What Is TENS?
TENS (Transcutaneous Electrical Nerve Stimulation) is
effective in relief of pain. It is used daily and clinically
proven by physiotherapists, caregivers, and top athletes
around the world. High-frequency TENS currents activate
the pain-inhibiting mechanisms of the nervous system.
Electrical impulses from electrodes, placed on the
skin over or near the pain area, stimulate the nerves to
block the pain signals to the brain, causing the pain go
unperceived. Low-frequency TENS currents facilitate the
release of endorphins, the body’s natural painkillers.