Therapeutic Modalities and Electrotherapy Flashcards

TENS (Transcutaneous Electrical Nerve Stimulation) in conventional mode works primarily through which pain mechanism?

Answer: Gate control theory

Conventional TENS uses high-frequency, low-intensity current to activate large-diameter A-beta sensory fibers, which inhibit pain signal transmission via the gate control mechanism.

Which ultrasound application technique is required when treating bony or irregular surface areas?

Answer: Water immersion technique

Water immersion ultrasound is used for irregular surfaces (hands, feet, ankles) because water provides a coupling medium and allows the transducer to maintain contact without direct pressure on bony prominences.

A patient is receiving NMES (Neuromuscular Electrical Stimulation) for quadriceps re-education post-ACL repair. The on:off ratio should be set to:

Answer: 1:5 to allow adequate muscle recovery between contractions

An on:off ratio of 1:5 (e.g., 10 seconds on, 50 seconds off) allows sufficient recovery time to minimize muscle fatigue during NMES strengthening sessions.

Which laser safety classification is typically used in therapeutic photobiomodulation (low-level laser therapy)?

Answer: Class 3B (medium power)

Therapeutic low-level laser therapy typically uses Class 3B lasers (5–500 mW), which require safety eyewear to prevent eye damage but are non-thermal for tissue.

What is the therapeutic depth of penetration for a hot pack (hydrocollator)?

Answer: 1–2 cm (superficial tissues)

Hot packs heat superficial tissues to a depth of approximately 1–2 cm; deeper muscles are not significantly heated by this modality.

Which of the following is a contraindication for the use of electrical stimulation?

Answer: Active malignancy in the treatment area

Electrical stimulation is contraindicated over areas of active malignancy because it may stimulate tumor cell proliferation or spread through increased blood flow.