Diathermy
Diathermy is electrically induced heat or the use of high-frequency electromagnetic currents as a form of physical therapy and in surgical procedures.
The idea that high-frequency electromagnetic currents could have therapeutic effects was explored independently around the same time (1890–1891) by French physician and biophysicist Jacques Arsene d'Arsonval and Serbian American engineer Nikola Tesla.
[2][3][7][8] He also developed the three methods that have been used to apply high-frequency current to the body: contact electrodes, capacitive plates, and inductive coils.
[2] In 1908 German physician Karl Franz Nagelschmidt coined the term diathermy, and performed the first extensive experiments on patients.
[4][5][6] The application of moderate heat by diathermy increases blood flow and speeds up metabolism and the rate of ion diffusion across cellular membranes.
The degree of heat and depth of penetration depend in part on the absorption of power as well as the electrical impedance of the current path between the electrodes, measured in ohms whose symbol is the Greek letter omega (Ω).
As highlighted by various studies, in summary, short waves, thanks to their thermal and non-thermal effects, are able to strengthen the microcirculation of the anatomical area treated (angiogenesis), therefore inducing an anti-edematous, anti-inflammatory, muscle-relaxing, pain-relieving and proregenerative.
Published studies have demonstrated not only their effectiveness, but also the increase in life expectancy of treated patients The devices that have proven to be effective use filters, suitable for the purpose, to be able to deliver a wave with a practically perfect sinusoidal curve or in any case to drastically reduce any harmonics, with an impedance range, calculated on the Interposed, therefore on known impedance values, in reference to the frequencies involved and the materials used.
High frequencies (8 MHz in particular) represent a very efficient means with which to transport the energy of the electromagnetic impulse directly to the anatomical site of interest: as the frequency increases, the resistance offered by the tissues is reduced, the impulse is therefore to go beyond the cell membrane and reach the deep tissues without significant energy dissipation.
From a technical point of view, the skin is not subject to a direct increase in temperature (there is no risk of scalds or burns) and the treatment can be focused quite precisely on the deep tissues of interest.
For this reason, no conductive gels or creams are needed and the user, a healthcare professional, can focus (hold the handpiece still) in a static manner on the part to be treated, for example for rhizarthrosis or in a post-operative situation on top of TNT Shortwave diathermy is usually prescribed to treat deep muscles and joints covered by a heavy mass of soft tissue, such as the hip.
Typically, hyperthermia would be added twice a week before radiation therapy, as shown in the photograph from a 2010 clinical trial at the Mahavir Cancer Sansthan in Patna, India.
Microwaves cannot be used in high dosage on edematous tissue, over wet dressings, or near metallic implants in the body because of the danger of local burns.
Nevertheless, adequately designed prospective-controlled clinical studies need to be completed to confirm the therapeutic effectiveness of hyperthermia with large number of patients, longer-term follow-up and mixed populations.
Electrosurgery and surgical diathermy involve the use of high-frequency A.C. electric current in surgery as either a cutting modality, or else to cauterize small blood vessels to stop bleeding.
[12] Monopolar electrocautery works because radio frequency energy is concentrated by the surgical instrument's small surface area.
The electrical circuit is completed by passing current through the patient's body to a conductive pad that is connected to the radio frequency generator.
