Physiotherapy & Rehab Engineering
Electrotherapy output verification and electrode safety, mechanical wear on load-bearing rehab equipment, and therapeutic ultrasound calibration.
Physiotherapy and rehab equipment spans a wide range from purely electrical (electrotherapy units) to purely mechanical (traction tables, gait-training frames), and the failure modes and risk profile differ sharply across that range.
Electrotherapy output verification
Electrotherapy devices - TENS (transcutaneous electrical nerve stimulation) and NMES/EMS (neuromuscular electrical stimulation) units - need real output verification: amplitude and pulse-width accuracy against the display, plus electrode/lead continuity. In practice, a "no output" complaint is far more often a cable or electrode fault than a unit fault - check continuity through the lead and electrode connection before assuming the stimulator itself has failed, since these are consumable, frequently-flexed components with a much higher wear rate than the unit's internal electronics.
Mechanical wear on load-bearing equipment
Mechanical rehab equipment - traction tables, continuous passive motion (CPM) units, parallel bars, gait-training frames - carries a real fall/injury risk from mechanical wear that's genuinely easy to under-prioritize as "just" a mechanical issue rather than treating it with the seriousness of an electrical safety fault. Frame and strap integrity checks belong in the same PM seriousness tier as electrical safety testing, not treated as cosmetic, because the failure consequence - a patient fall or equipment collapse during active use - is comparably severe even though the failure mechanism is mechanical rather than electrical.
Therapeutic ultrasound calibration
Therapeutic ultrasound applicators (distinct from diagnostic imaging ultrasound covered in Chapter 24) have their own output calibration check - verifying actual acoustic power output against the display, since under-dosing reduces treatment efficacy and over-dosing is a real tissue-heating risk to the patient. This calibration uses a dedicated ultrasound power meter, not a general-purpose instrument, and it's a distinct discipline from the imaging-transducer care described in the Medical Imaging chapter despite both involving ultrasound technology.