Cold Modalities

Question 1

4 mechanisms of transference of thermal energy

Answer 1

CONDUCTION: heat lost or gained through directs contact
CONVECTION: heat lost or gained through movement of fluid or air between regions of unequal temperature
RADIATION: emission of energy
CONVERSION: changing from one energy form to another

Question 2

conduction

Answer 2

heat lost or gained through direct contact

• temp change depends on
• – the temp diffrerence between the 2 surfaces
• – duration of exposure (time surfaces in contact)

ex:

• ice massage
• cold packs
• hydrocollator packs
• cold spray
• ice immersion
• contrast baths
• cyro cuff
• paraffin bath

Question 3

convection

Answer 3

heat loss or gain though movement of fluid or air between regions of unequal temp
= temp change depends on
  --- differences in temp
  --- duration of exposure
  --- size of area to be treated

ex:

• hot whirlpool
• cold whirlpool
• fluidotherapy

Question 4

radiation

Answer 4

emission of energy
- may be emitted from a source (heat lamp) and absorbed by body

ex:

• infrared lamps
• laser
• uv lamps

Question 5

conversion

Answer 5

changing from one energy form into another

ex:
- ultrasound converts acoustic energy into thermal energy
- diathermy

Question 6

cryotherapy

Answer 6

application of cold modalities with temp 32 - 65 deg F (0 deg C)

• heat removed fro body and absorbed by modality
• local and systemic effects

Question 7

thermal agent

Answer 7

represent transfer of heat energy to or away from tissue
- heat transfer is unidirectional
- fundamental principle: one object must have higher temp than other
“tissues warm cold modalities by losing heat to them”
“cold modalities work by absorbing heat from their immediate environments”

Question 8

how cryotherapy works

Answer 8

• lowers metabolic rate of tissue
• -> limits suffocating cell’s need for oxygen
• —> reduced seondary metabolic (hypoxic) injury
• lowering temp by 1 deg C = 13% decrease in metabolic rate
• during 20 min ice application = cell metabolism decreases by 19%

Question 9

Effects of Cold on Cellular Response

Answer 9

decrease in cell metabolism –> less need for oxygen

Question 10

effects of cold on blood and fluid dynamics

Answer 10

• vasoconstriction
• decrease blood flow to area
• decrease hydrostatic pressure
• decrease capillary permeability

Question 11

effects of cold on inflammation

Answer 11

• decreased inflammation
• decrease release of inflammatory mediators
• decrease prostroglandin synthesis
• decrease capillary permeability (decreasing histamine)

Question 12

effects of cold on nerve conduction

Answer 12

• reduced afferent NCV

- reduced threshold of afferent nerve endings

Question 13

cold on pain

Answer 13

cold

• -> decreases capillary permeability
• —> decreases edema formation
• ——> lessens mechanical pressure on nerves
• ———-> reducing pain
• –> decreases amount of inflammatory mediators
• —-> decreased amour of cellular waste by-products (cause tissue damage and pain)
• ———> less tissue damage/pain

Question 14

effects of cold on muscle spasm

Answer 14

decrease sensitivity of muscle spindle

• -> muscle relaxes
• —-> spasm relieved

Question 15

cold affects pain perception and transmission by…

Answer 15

• interrupting pain transmission (stimulates large diameter A-beta n. fibers) via gate theory
• decrease nerve conduction velocity
• reducing muscle spasm
• reducing / limiting edema

Question 16

indications for cold

Answer 16

• acute injury or inflammation
• acute or chronic pain
• post-surgical pain and inflammation
• use in conjunction with rehab exercises
• small, superficial 1st degree burns (ointment, refer anyway)
• acute or chronic muscle spasm
• neuralgia
• spasticity due to CNS disorder

Question 17

contraindications

Answer 17

• cold allergy / cold-induced urticaria
• cardiac and respiratory involvement
• PVD/circulatory insufficiency
• uncovered/open wounds
• anesthetic skin
• advanced diabetes
• Raynaud’s phenomenon
• prolonged application over superficial nerve

Question 18

Temp and duration Parameters

Answer 18

ice bag: 10-20 min
cryocuff: 15-30 min (20)
ice cup: 5-10 min
immersion: 10-20 min 40-50 deg F
(more body = higher temp)
whirl pool: 20 min 55-65 (50) deg F