NPTE-PT Equipment and Therapeutic Modalities 2 — Questions and Answers
Question 1: A patient with chronic low back pain is treated with ultrasound. Which parameter setting produces the greatest depth of penetration?
- 1 MHz at 100% duty cycle (Correct answer)
- 3 MHz at 50% duty cycle
- 1 MHz at 50% duty cycle
- 3 MHz at 100% duty cycle
Correct answer: 1 MHz at 100% duty cycle
1 MHz ultrasound penetrates deeper (up to 5 cm) than 3 MHz because lower frequency waves attenuate less in tissue.
Question 2: Which type of traction is MOST appropriate for a patient with acute cervical radiculopathy who cannot tolerate positional changes?
- Intermittent mechanical traction
- Continuous mechanical traction
- Manual traction in supine (Correct answer)
- Positional traction
Correct answer: Manual traction in supine
Manual traction in supine allows the therapist to control force precisely and immediately release if symptoms worsen, making it safest for acute conditions.
Question 3: A physical therapist is setting up a TENS unit for postoperative pain. Which mode delivers a continuous high-frequency, low-intensity current most effective for immediate pain relief?
- Burst mode TENS
- Acupuncture-like TENS
- Conventional (high-frequency) TENS (Correct answer)
- Brief-intense TENS
Correct answer: Conventional (high-frequency) TENS
Conventional TENS (80–150 Hz, low intensity) activates gate control mechanisms for rapid, short-duration analgesia.
Question 4: When using iontophoresis to deliver dexamethasone for inflammation, which electrode placement is correct?
- Dexamethasone under the positive electrode
- Dexamethasone under the negative electrode (Correct answer)
- Dexamethasone alternated between both electrodes
- Electrode polarity is irrelevant for dexamethasone
Correct answer: Dexamethasone under the negative electrode
Dexamethasone is negatively charged, so it must be placed under the negative (cathode) electrode for proper ion delivery.
Question 5: A patient with Raynaud's phenomenon is being considered for cryotherapy. What is the PRIMARY contraindication?
- Active infection
- Cold hypersensitivity / vasospastic disorder (Correct answer)
- Impaired sensation
- Open wound
Correct answer: Cold hypersensitivity / vasospastic disorder
Raynaud's phenomenon involves pathological vasospasm triggered by cold, making cryotherapy directly contraindicated.
Question 6: During fluidotherapy treatment, the therapist notices the patient has an open wound on the treated extremity. What is the MOST appropriate action?
- Continue treatment with a water-proof dressing
- Discontinue treatment immediately (Correct answer)
- Lower the temperature setting below 38°C
- Increase the cellulose particle agitation to improve circulation
Correct answer: Discontinue treatment immediately
Open wounds are a contraindication to fluidotherapy due to risk of infection from the circulating cellulose particles.
Question 7: A therapist applies shortwave diathermy to a patient with a total knee replacement. Why is this contraindicated?
- Metal implants concentrate electromagnetic energy, causing excessive heating (Correct answer)
- Diathermy increases joint effusion around implants
- The magnetic field demagnetizes the implant
- Shortwave diathermy is only contraindicated for pacemakers
Correct answer: Metal implants concentrate electromagnetic energy, causing excessive heating
Metal implants reflect and concentrate shortwave diathermy energy, creating dangerous temperature elevations in surrounding tissue.
NPTE-PT Equipment and Therapeutic Modalities 2
A patient with chronic low back pain is treated with ultrasound.
Which parameter setting produces the greatest depth of penetration?