How physiotherapy generates problems

Electrotherapy is the treatment of patients by electrical means. Normally, electrotherapy means applying some form of energy to the body. The form of this energy varies. It may be electric currents, mechanical energy such as ultrasound, electromagnetic fields at radio frequencies, heat (infrared), light or ultraviolet radiation. The sources of energy used by the therapist are varied and the frequencies used vary from direct current to ultraviolet light. The author gives a summary of the main modalities used in today´s physiotherapy department. In terms of electromagnetic interference, there are three main considerations. Firstly, what power levels are applied to the patient to give effective treatment? The higher the power level the more likely the power generator is to interfere with other equipment. Secondly how easy is it to restrict the energy to the patient environment? If we can make sure that all the energy is either applied to the patient or contained by appropriate screens then interference will not be a problem. Thirdly, is the energy source a continuous wave or modulated (pulsed)? This is important because some equipment will respond to the modulation frequency of a radiated wave and not the carrier frequency. The author discusses shortwave therapy in particular and interference control