Chapter 1 - The Basic Science

Question 1

Therapeutic modalities

Answer 1

A device of technique that delivers a physical agent to the body for therapeutic purposes

Question 2

Relevant forms of energy

Answer 2

Electromagnetic
Thermal
Electrical
Sound
Mechanical

Question 3

Electromagnetic energy

Answer 3

Radiation - process by which EME travels from its source outward through space

Photons - energy carrier that composes all EM radiation

Question 4

How are wavelength and frequency related?

Answer 4

Inversely related

Photons with longer wavelengths have shorter frequencies
Shorter wavelengths have higher frequencies

Question 5

How are energy and frequency related?

Answer 5

Directly proportional

Energy of a photon is directly proportional to its frequency
EMR with higher frequency also has higher energy

E=hv

H=plancks constant (6.626 x 10^-34 J*s)

Question 6

How is EME produced?

Answer 6

UV, IR and visible light have been produced by heating objects to very high temps

IR—>VL—>UV

Question 7

What are the effects of EMR on tissue

Answer 7

Longer wavelengths are more penetrating

At the low E end of the spectrum, the basic effect is to heat tissues

Question 8

Diathermies

Answer 8

Large regions of radiation with longer wavelengths than IR

Includes shortwave and microwave radiation
Penetrates deeper than IR or VL

Question 9

Arndt-Schultz principle

Answer 9

No reactions or changes can occur in the body tissues if the amount of E absorbed is insufficient to stimulate the absorbing tissues

Question 10

Law of Grotthuss-Draper

Answer 10

Energy not absorbed by tissues must be transmitted

Question 11

Cosine Law

Answer 11

Optimal radiation occurs when the source of radiation is at right angles to the center of the area being radiated

Question 12

Inverse square law

Answer 12

Intensity of radiation depends on the object’s distance from the radiating source…further away, less intense

Question 13

Diathermy

Answer 13

EME modality

High frequency

Produces heat as it is absorbed by tissue cells, resulting in a temp increase
Shortwave may either be continuous or pulsed
Continuous shortwave and microwave are used for thermal effects
Pulse shortwave is used for non thermal effects

Question 14

LASER

Answer 14

Light therapy, EME modality

Light Amplification by Stimulated Emission of Radiation

Can produce light in either infrared or visible portion of spectrum
Low-level laser therapy (LLLT) produces little to no thermal effects but may have effect on soft-tissue, fracture healing, and pain management

Question 15

LED

Answer 15

Light therapy, EME modality

Light Emitting Diode

Wavelengths of LED are mostly in the red or near infrared ranges
Effective for pain modulation, skin inflammation, wounds and skin ulcer healing, skin rejuvenation, and various orthopedic conditions.