Which of the following is a warning sign that NMES may be causing tissue damage?

• A. Mild warmth under the electrodes.
• B. Redness that appears after treatment but resolves without issue.
• C. Skin dryness near electrode sites.
• D. Persistent numbness or tingling after treatment.

Answer: (D)

During NMES, you want to monitor for signs that go beyond temporary, normal sensations. A lasting numbness or tingling after the session is the best warning that tissue or nerve tissue may be affected by the stimulation. This kind of persistent sensory change can indicate nerve irritation or potential injury from too high current density, too long a duration, or poor electrode contact. Because it suggests an ongoing disruption of sensation rather than a normal transient response, it warrants stopping the treatment and rechecking all parameters and skin condition, then reassessing before continuing.

By comparison, mild warmth under the electrodes can be a normal feel as blood flow increases and the skin heats slightly; redness after treatment that resolves is typically a temporary skin reaction and not a sign of tissue damage; dryness near the electrode site can occur with use but does not by itself indicate injury. If numbness or tingling sticks around, that’s the signal to pause and evaluate.