Ultrasound (US)
Ultrasound (US) is a form of mechanical energy, not electrical energy and therefore strictly speaking, not really electrotherapy at all but does fall into the Electro Physical Agents grouping.
As the US wave passes through a material (the tissues), the energy levels within the wave will diminish as energy is transferred to the material.
The energy absorption and attenuation characteristics of US waves have been documented for different tissues:
- Ligaments
- Tendon
- Fascia
- Joint Capsule
- Scar tissue
Pulsed Shortwave (PSW)
Pulsed Shortwave (PSW) is a widely used modality in the UK. The primary effects of the pulsed magnetic field appears to be at the cell membrane level and is concerned with the transport of ions across the membrane.
The clinical effects of PSW are primarily related to the inflammatory and repair phases in musculoskeletal / soft tissues:
- Muscle
- Nerve
- Areas of Oedema
- Haematomas and Effusion
Inferential (IF)
There are 4 main clinical applications for which IF appears to be used:
- Pain relief
- Muscle stimulation
- Increased local blood flow
- Reduction of oedema
As IF acts primarily on the excitable (nerve) tissues, the strongest effects are likely to be those which are a direct result of such stimulation (i.e. pain relief and muscle stimulation). The other effects are more likely to be secondary consequences of these.


