DIATHERMY

Diathermy

Diathermy

Introduction

Diathermy is an electrotherapeutic procedure which uses heat induced by the high frequency electrical current. The tissue and body organs are deeply warmed; the local metabolism is enhanced. The elasticity of ligament improves and pain is reduced. The indications include chronic diseases of joints, ligaments and sinews, chronic gynecological inflammations, urgent urinary incontinence and post-operative states.

Discussion

Diathermy is also used in surgical procedures. Many doctors use electrically heated probes to seal blood vessels to prevent excessive bleeding. This is particularly helpful in neurosurgery and eye surgery. Doctors can also use diathermy to kill abnormal growths, such as tumors, warts, and infected tissues (Thom, 1966).

Monopolar diathermy

Electrical plate is placed on patient and acts as indifferent electrode

Current passes between instrument and indifferent electrode

As surface area of instrument is an order of magnitude less than that of the plate

Localised heating is produced at tip of instrument

Minimal heating effect produced at indifferent electrode

Bipolar diathermy

Two electrodes are combined in the instrument (e.g. forceps)

Current passes between tips and not through patient

Origins

The therapeutic effects of heat have long been recognized. More than 2,000 years ago, the Romans took advantage of heat therapies by building hot-spring bathhouses. Since then, various methods of using heat have evolved. In the early 1890s, French physiologist Arséne d'Arsonval began studying the medical application of high-frequency currents. The term diathermy was coined by German physician Carl Franz Nagelschmidt, who designed a prototype apparatus in 1906 (Michlovitz, 1996). Around 1925, United States doctor J. W. Schereschewsky began studying the physiological effects of high-frequency electrical currents on animals. It was several years, however, before the fundamentals of the therapy were understood and put into practice (Michlovitz, 1996).

Types of diathermy

There are two types in common use: ultrarsonic diathermy, and electromagnetic diathermy (Memon, 1994).

Ultrasonic diathermy refers to heating of tissues by ultrasound for the purpose of therapeutic deep heating. No tissue is ordinarily damaged hence it is generraly used in biomedical applications.

Electrromagnetic diathermy uses high frequency alternating electric or magnetic fields, sometimes with no electrode or device contact to the skin, to induce gentle deep tissue heating by induction. Again, no tissue is ordinarily damaged.

Diathermy Works

The Diathermy energy field pases through softer surface tissues and turns to heat when reaching more dense tissues. The heat increases circulation and helps to speed the healing process (Aigner et al, 1997).

Heat speeds up healing by increasing blood flow to the injury. It may be used after cold treatments when ...