10 - Diathermy

Question 1

Diathermy def

Answer 1

high-frequency electromagnetic energy

Question 2

Shortwave diathermy

Answer 2

electrodes beams short waves into body part

• MC type of unit
• uses radio transmitter

Question 3

Microwave diathermy

Answer 3

applicator beams microwaves to part

• not as safe shortwave
• FCC regulated

Question 4

thermal effects

Answer 4

• dipole rotation = rotating molecules with two charges (ie water)
• ionic oscillation = ions will oscillate back and forth (ie, sodium, potassium, chlorine)
• kinetic energy from rotation –> thermal energy

Question 5

Diathermy electrode types

Answer 5

• capacitor electrode –> electrical field
• induction electrode –> magnetic field

Question 6

Capacitive technique

Answer 6

• tissue placed an electric field
• greatest absorption and tissue with low electrolyte and water content
• use with:patients/areas with low subcutaneous fat

Question 7

Inductive technique

Answer 7

MC type

• tissues placed an oscillating magnetic field
• greatest absorption in high electrolyte, high dipole tissue (deep, muscle/tendon/joint)
• use with: patients with more subcutaneous fat

Question 8

Four laws of diathermy

Answer 8

1. Arndt-Schultz law:dose versus response
   
   • dose versus response
   • low dose = stimulation, high dose = inhibition
2. Grotthus-draper law
   
   • absorbed versus therapeutic effect
3. inverse square law
   
   • dose versus divergence
   • intensity = 1/(distance)²
4. cosine law
   
   • application of angle
   • reduce energy if angle is moved out of 90°

Question 9

diathermy types of interaction

Answer 9

• transmission
• absorption
• reflection
• refraction
• scatter

Question 10

Continuous shortwave diathermy (CSWD)

Answer 10

• less common

Question 11

Pulsed shortwave diathermy (PSWD)

Answer 11

• MC
• heat versus no he

Question 12

Diathermy heat used for

Answer 12

• pain relief
• wound management
• joint contracture

Question 13

Counterirritation

Answer 13

using another stem to distract the body thus preventing pain signals from being perceived

Question 14

Diathermy indications

Answer 14

• research
• muscle skeletal injuries/pain

Question 15

Diathermy risk factors

Answer 15

• pregnant operator
• copper IUDs
• other patients near device
• other EPA devices
• mentally confused patients