What is a monopolar setup?

• A. One big, one small
• B. Two of equal size
• C. Two active electrodes
• D. Three electrodes in use

Answer: (A)

In a monopolar setup, there is one active electrode placed on the treatment area and a large dispersive (return) electrode placed elsewhere on the body. The active electrode is typically smaller to create a higher current density at the treatment site, while the large dispersive pad spreads the current over a wider area to keep the skin exposure low and safe. This arrangement is exactly captured by “one big, one small,” which describes having a small active electrode and a larger return electrode.

Two electrodes of equal size imply a bipolar setup, where both electrodes actively deliver current between them. Having two active electrodes or three electrodes in use describes other configurations that aren’t monopolar.