1. ESAT 3640 Therapeutic Modalities
Thermal Modalities
ESAT 3640
Therapeutic Modalities

2. Infrared Modalities
Ice packs, hot packs, paraffin bath, H/C whirlpools are all infrared modalities
Wavelength and frequency that falls within the infrared region

3. Mechanisms of Heat Transfer
Conduction
Convection
Radiation
Conversion

4. Appropriate Use of Infrared Modalities
Sometimes abused by athletic trainers
Don’t use just because you have it available
Know benefits of use

5. Terminology Related to Infrared Modalities
Thermotherapy
Cryotherapy
Hydrotherapy

6. Clinical Applications
Effect is primarily superficial and directly affects cutaneous blood vessels and cutaneous nerve receptors
Depth of penetration is 1 cm or less
Used primarily to provide analgesia and pain reduction

7. Clinical Applications continued
Cutaneous heat can cause a reflexive increase in blood flow to underlying tissue
Cutaneous cold can decrease blood flow in injured area
If primary goal is to decrease temperature and decrease blood flow to injured area you must use ice or cold application

8. Effects of Tissue Temperature Change on Circulation
Main physiological effect is on superficial circulation
Circulation through skin serves 2 major functions
Nutrition of skin
Conduction of heat from internal structures

9. Circulatory Apparatus
Arteries, capillaries, and veins
Vascular structures for heating the skin
Subcutaneous venous plexus
Arteriovenous anastomosis

10. Response of Circulatory Apparatus to Cold
Cold application to the skin causes constriction of the skin vessels to a temperature of 57° F
At temperatures below 57° F vessel begin to dilate

11. Thermoreceptor Response
Both cold and warm receptors adapt rapidly to temperature change
The faster the temperature change; the more rapid the receptor adaptation
Small vs. Large surface areas

12. Hypothalamic Centers
Stimulation of anterior hypothalamus causes cutaneous vasodilation
Stimulation of the posterior hypothalamus causes cutaneous vasoconstriction

13. Effects of Tissue Temperature Change on Muscle Spasm
Physiological mechanism related to heat or cold treatment in the reduction of muscle spasm lie at the level of the muscle spindle, GTO, and the gamma efferent system
Heat has relaxing effect
Lessens stimulus threshold of muscle spindle
Decrease in gamma efferent firing rate

14. Effects of Tissue Temperature Change on Muscle Spasm Continued
Cold decreases local neural activity
GTO firing rate decreases
Decreased rate of afferent activity with increased amount of tension on the muscle
Miglietta study

15. Physiologic Effects of Tissue Cooling
Local decrease in temperature
“primary reason for using cold in acute injury is to lower the temperature in the injured area, thus reducing the metabolic rate with a corresponding decrease in production of metabolites and metabolic heat”
Ho, et al Am J Sports Med 23(1): 74-76, 1995
Cold + Compression is most effective

16. Progression of Sensations Related to Cold
Burning
Aching
Analgesia
numbness

17. Effects of Cold and Heat on Inflammation
Reduction in release of inflammatory mediators
Decreased prostaglandin synthesis
Decreased capillary permeability
Heat
Accelerate inflammation

18. Pain Control Cold Heat Gate Theory Gate theory
Increased blood flow = removal of waste product
Removal of swelling

19. Physiological Effects of Heat & Cold

20. Indications and Contraindications – Cold

21. Indications and Contraindications – Heat

22. Cryotherapy Techniques
Ice packs
Ice massage
Cold whirlpool
Cold spray
Ice immersion
Cryo-cuff
Contrast bath

23. Thermotherapy Techniques
Hydrocollator packs
Warm whirlpool
Paraffin bath
Fluidotherapy