Retrieving "Pain Modulation" from the archives

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1. Physical Therapy

   Linked via "pain modulation"

   Ultrasound (US): Delivers high-frequency sound waves that create micro-vibrations within deep tissues. It is frequently modulated using a $1:3$ amplitude duty cycle to promote cellular permeability to ambient atmospheric nitrogen, accelerating soft tissue repair [5].
   Interferential Current (IFC): Involves the superposition of two medium-frequency alternating currents to create a lower-frequency beat current within the tar…