Cryotherapy

Question 1

what does cold generally produce

Answer 1

vasoconstriction

Question 2

direct effects of cold

Answer 2

1. Increase in blood viscosity
2. Cutaneous thermoreceptors
3. Decreased production of vasodilators

Question 3

indirect effects of cryotherapy

Answer 3

Cutaneous thermoreceptors cause a reflexive action of the sympathetic adrenergic neurons → vasoconstriction

Question 4

Cold Induced Vasodilation

Answer 4

 Occurs with tissue temperatures < 10° C
 Normal response aka “hunting response”
 Occurs with longer periods of exposure
 Occurs 1° in distal extremities

Question 5

Neuromuscular effects of cryotherapy

Answer 5

• decreased nerve conduction velocity
• increased pain threshold
• altered muscle strength
• decreased spasticity
• facilitation of muscle contraction

Question 6

decreased nerve conduction velocity

Answer 6

 Temperature ↓ → NCV ↓
 Effects reverse quickly unless exposure is prolonged
 Effects both motor and sensory nerve, but greatest effect found in myelinated and small fibers

Question 7

increased pain threshold

Answer 7

 Occurs due to counter irritant effect via the gate control mechanism

Question 8

altered muscle strength

Answer 8

 Isometric strength ↑ after 5 min. of icing
o Brief cooling facilitates motor neuron excitement
 30 + minutes of cooling → ↓ Isometric strength
o 2° ↓ blood flow → ↓ NCV

Question 9

decreased spasticity

Answer 9

 Tissue temperature ↓ causes an initial ↓ in gamma motor neuron activity as a reaction to stimulation of the cutaneous receptors
 Continued cooling will cause a ↓ in afferent muscle spindle activity and GTO activity

Question 10

facilitation of muscle contraction

Answer 10

Results from the mechanism listed above with facilitation of motor neuron activity resulting from a ↓ in gamma motor neuron activity

Question 11

metabolic effects of cryotherapy

Answer 11

 Cold ↓ metabolic activity ∴ is useful in controlling acute inflammation, but not good for tissue healing.
 Short term post injury cold applications do not eliminate swelling but has sown some ability to limit the amount of post injury swelling
 Intense cold and cold applied for long periods may actually increase edema formation

Question 12

positive metabolic effects of cryotherapy

Answer 12

lowered oxygen demand and metabolism, reduced leukocyte and macrophage adherence and decrease intramuscular pressure which outweigh presence of increased edema

Question 13

indications for cryotherapy

Answer 13

• contro inflammation
• edema
• pain control
• modify spasticity
• MS management
• muscle facilitaiton
• cryokinetics and cryostretch

Question 14

cold to control inflammation

Answer 14

 Control acute inflammation
 Reduce pain
 Acute inflammation in chronic inflammatory condition

Question 15

ice for edema

Answer 15

 When associated with inflammation
 Should be accompanied by compression and elevation
 Not desirable for edema 2° to immobilization and impaired circulation

Question 16

ice for pain control

Answer 16

 Block or ↓ conduction of A-delta fibers
 ↓ pain/spasm cycle

Question 17

ice to modify spasticity

Answer 17

 Temporary ↓ in spasticity (caused by UMN dysfunction)
 Cold application for up to 5 min → ↓ in DTR
 10-30 min. – see ↓ in clonus and resistance to passive stretch

Question 18

ice for MS management

Answer 18

Cooling vests have shown ↓ in tremors and fatigue

Question 19

cold for muscle facilitation

Answer 19

quick icing for flaccidity

Question 20

ice for cryokinetics and cryostretch

Answer 20

 Fluro-ethyl spray gives topic numbness to allow less pain with aggressive stretch.
 Numbness in general to improve stretch
 Prolonged cooling to increase strength

Question 21

precautions/contraindications

Answer 21

 Cold hypertension (uitcaria)
 Cold intolerance
 Cryoglobulinemia
 Proximal cold hemoglobinuria
 Raynaud’s disease/phenomenon
 Over a regenerating peripheral nerve
 Circulatory compromise
 Over the superficial main branch of a peripheral nerve
 Open wound
 Hypertension
 Poor sensation
 Poor communication skills