NPTE-PTA Therapeutic Modalities and Electrotherapy 2

Question 1

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

Accepted Answer

Gate control theory

Answer

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.

Question 2

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

Accepted Answer

Water immersion technique

Answer

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.

Question 3

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

Accepted Answer

1:5 to allow adequate muscle recovery between contractions

Answer

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.

Question 4

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

Accepted Answer

Class 3B (medium power)

Answer

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.

Question 5

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

Accepted Answer

1–2 cm (superficial tissues)

Answer

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

NPTE-PTA - National Physical Therapy Examination for Physical Therapist Assistants Practice Test

NPTE-PTA - National Physical Therapy Examination for Physical Therapist Assistants Practice Test

NPTE-PTA Therapeutic Modalities and Electrotherapy 2