Electrode placement is based on where in the body a patient is feeling pain, according to Tensunits.com. For example, electrodes are placed on the lower back to ease pain in the femur or knee. Consult the Electrode Placement Chart on the TENS website for detailed instructions and diagrams.
A Transcutaneous Electrical Nerve Stimulation, or TENS, machine works by sending pulses of low-voltage electrical currents across the skin and along the nerve stands to ease pain, according to WebMD. Electrodes applied to the skin conduct the current from the machine to the body. TENS therapy is recommended for a variety of muscle, joint or bone problems such as osteoarthritis, fibromyalgia, tendinitis, bursitis and other conditions. Experts generally agree that TENS therapy is safe, but the machine can cause harm if improperly used.