Therapeutic Modalities, Exercise Prescription, and Rehabilitation Technology
What is tested
Parameter accuracy for electrophysical agents, safe indications, and exercise prescription that follows established dose principles.
Core rules
- TENS. Conventional: 80–120 Hz, 50–150 µs, sensory-level analgesia. Acupuncture-like: 2–4 Hz, 200–250 µs. Avoid over the carotid sinus, pregnant abdomen and eyes, and use caution with implanted devices.
- Ultrasound. 1 MHz for deep tissue (about 3–5 cm), 3 MHz for superficial tissue (1–2 cm); 0.5–2.0 W/cm²; continuous for chronic, pulsed (e.g. 20% duty cycle) for acute. Contraindicated over malignancy, infection, DVT, growth plates, eyes, gonads and the pregnant uterus.
- Thermal agents. Cold for acute oedema and pain, 15–20 minutes with skin checks; heat for chronic stiffness, never on acute inflammation or impaired sensation.
- Exercise dose (FITT-VP). Aerobic: 150 minutes weekly moderate, or 75 minutes vigorous. Resistance: 2–3 days weekly, 2–4 sets of 8–12 repetitions at 60–70% of 1RM. Flexibility and balance as indicated.
- Principles. Overload, specificity, progression, reversibility; start below capacity and progress by roughly 5–10% weekly.
- Assistive devices. Cane length to wrist crease or greater trochanter, held on the side opposite the affected limb; walker frames for wider support.
Worked example
A 65-year-old with knee osteoarthritis and controlled hypertension wants to start exercise. Reasoning: no cardiac contraindication, so prescribe moderate aerobic work (walking, cycling) building to 150 minutes weekly at RPE 12–14, plus twice-weekly quadriceps and hip strengthening of 2 sets of 10–12, and a home programme. Give warning signs, a review date, and record baseline pain and function.
Traps
Continuous ultrasound over a metal implant or open growth plate; using motor-level TENS and calling it sensory; prescribing maximal intensity without a baseline; progressing load before tissue tolerates it.