DPT Electrotherapy & Modalities 5

Question 1

A patient has a demand-type cardiac pacemaker. Which electrotherapy modality poses the GREATEST risk of interference?

Accepted Answer

TENS with conventional mode (80–150 Hz)

Answer

TENS, especially at higher frequencies, can produce electrical signals that mimic cardiac activity, potentially inhibiting a demand pacemaker and causing arrhythmia.

Question 2

The beam non-uniformity ratio (BNR) of an ultrasound transducer indicates:

Accepted Answer

The ratio of peak to average spatial intensity within the beam, where lower is safer

Answer

BNR is the ratio of peak spatial intensity to average spatial intensity; values closer to 1:1 indicate a more uniform beam, reducing risk of hot spots.

Question 3

Which waveform is classified as monophasic and is most commonly used for wound healing in HVPC?

Accepted Answer

Twin-peak monophasic

Answer

HVPC uses a twin-peak monophasic waveform with very short pulse durations (< 200 µs) and high peak voltages (> 100 V), producing minimal electrochemical effects at the electrodes.

Question 4

During fluidotherapy treatment, the active ingredient that provides therapeutic benefit is:

Accepted Answer

Cellulose particles suspended in warm dry air providing convective heat and sensory stimulation

Answer

Fluidotherapy uses finely divided cellulose particles agitated in a stream of warm air, delivering dry heat via convection and providing desensitization through sensory bombardment.

Question 5

A therapist is using neuromuscular electrical stimulation (NMES) for quadriceps strengthening post-ACL reconstruction. The optimal on:off ratio to minimize fatigue while building strength is:

Accepted Answer

1:5 (short on, long off)

Answer

A 1:5 on:off ratio (e.g., 10 s on, 50 s off) allows adequate recovery between contractions to minimize fatigue and maintain contraction quality during early rehabilitation.

(DPT) Board Certified Doctor of Physical Therapy Practice Test

(DPT) Board Certified Doctor of Physical Therapy Practice Test

DPT Electrotherapy & Modalities 5