Lecture 6 - Hot and Cold

Question 1

define pain

Answer 1

• unpleasant sensory and emotional experience associated with actual or potential tissue damage

Question 2

what are pain receptors?

Answer 2

• aka nocioceptors
• sensitive to mechanical, thermal and chemical

Question 3

what are afferent nerves?

Answer 3

• fibres that carry information from nocioceptors towards the spinal cord

Question 4

what are the two types of pain signals?

Answer 4

• A delta
• C fibres

Question 5

what are A delta signals?

Answer 5

• myelinated
• fast pain (reflexes)
• large diameter
• touch, pressure, and temperature
• located in skin

Question 6

what are C fibres?

Answer 6

• unmyelinated
• slow pain
• small diameter
• pain and temperature
• located in the skin and deep tissue (muscle/ligament)
• reminder of the stupid thing you did (hurt yourself yesterday, feel it today)

Question 7

what are the steps of gate control?

Answer 7

• A beta and C nerve fibres are quiet (not stimulated), and T is blocked (gate is closed) so no pain
• with pain stimulation, C becomes active, activating T cells (not blocking), gate is open, so pain is present
• with non-painful stimulation, A is active, T is blocked (gate is closed), no pain
• A delta is never blocked (reflex pain)

Question 8

what are the types of A-beta input?

Answer 8

• pressure = rubbing/massaging
• vibration = tapping body to release opiates and close gate
• position sense = shaking finger (AROM/PROM)

Question 9

what happens when A fibres accommodate to constant input?

Answer 9

• site under nerve stimulation shows a decrease in excitability
• no longer receiving sensation to the body
• rise in threshold

Question 10

what is the hunting response?

Answer 10

• after 10-15 minutes of cold treatment, the blood flow will fluctuate
• cold-induced vasodilation (CIVD) occurs

Question 11

what does the body’s response to cold/ice/cryotherapy depend on?

Answer 11

• media being applied (ice, water, sprays, etc.)
• conductivity of area being cooled (fat vs muscle vs joint)
• length of exposure time (10 on 10 off is superior)

Question 12

what is happening to tissue in acute injuries?

Answer 12

• tissue injury (primary and secondary)
• cell death due to hypoxia
• increased bleeding to the area (bruising)
• pain
• swelling/edema (cell death from no oxygen)

Question 13

what are the physiological responses to cryotherapy?

Answer 13

• decreased muscle guarding
• decreased blood flow
• decreased capillary permeability
• decreased metabolic rate
• decreased collagen elasticity
• increased joint stiffness
• edema?
• decreased pain perception

Question 14

why might ice not be the best idea?

Answer 14

• inflammatory/destructive phase is necessary
• may slow down healing during the first stage of healing (3-7 days)

Question 15

why is ice a good idea?

Answer 15

• good for pain (myelination)
• decreases swelling when combined with exercise
• improvement in function with exercise
• maintains cell viability (decreased chemical reactions)

Question 16

what does the body’s response to heat/thermotherapy depend on?

Answer 16

• type of heat (moist vs dry vs ultrasound)
• intensity of heat
• duration of application (peaks after 6-8 minutes, temp doesn’t drop until heat is removed)

Question 17

what are the physiological responses to thermotherapy?

Answer 17

• increased blood flow
• increased capillary permeability
• increased metabolic rate
• increased collagen elasticity
• decreased joint stiffness
• decreased muscle spasm
• edema??? (increased in ischemic stage, low at the end)
• decreased pain

Question 18

what is the inflammation/destruction phase?

Answer 18

• first 2-4 days
• tissues are red, hot, swollen, painful
• primary or secondary tissue damage
• want to optimize healing environment, palliate pain and decrease swelling

Question 19

what does peace and love stand for?

Answer 19

• protection
• elevation
• avoid
• compression
• education
• load
• optimism
• vascularization
• exercise

Question 20

what does police stand for?

Answer 20

• protect
• optimal
• loading
• ice
• compression
• elevation

Question 21

what is protection?

Answer 21

• shield, unload and prevent joint movement
• control inflammation and prevent further injury

Question 22

what is loading?

Answer 22

• replacing rest with balanced incremental rehab
• safe cardio for example (vascularization)
• functional rehab (weight bearing and movement)

Question 23

what is compression?

Answer 23

• decreases local edema
• disperse edema to increase absorption
• elastic bandage can limit blood flow

Question 24

what is elevation?

Answer 24

• no reduction of blood flow until 30cm above the heart
• 50 cm = 80% of normal
• 70 cm = 65% of normal
• higher = better

Question 25

what is optimism and education?

Answer 25

• educate athletes of active process of rehab
• why you do each step
• measure progress
• set goals

Question 26

what are the clinical pearls of icing?

Answer 26

• put ice on people, not people on ice
• ice with water in plastic bag on skin is best
• compression overtop is best (towel, bandage)
• temperature gel packs are too cold to put directly on the skin, stay cold for a very long time

Question 27

what are the goals at the repair/fibroblastic phase?

Answer 27

• laying down tissue (not yet organized or liable)
• protect tissue
• idealize healing environment
• increase blood flow (heat)
• idealize ROM
• gentle strengthening
• proprioception

Question 28

why is heat good in the fibroblastic and remodeling stages?

Answer 28

• increase blood flow
• promote healing
• decrease spasm
• increase collagen elasticity
• decrease stiffness
• increase ROM (without tearing)

Question 29

what are the goals of the remodelling/maturation phase?

Answer 29

• change type 3 to type 1 collagen (destroy and rebuild)
• realign fibres
• idealize strength
• add functional movements
• prepare for return to play
• (pain is okay during treatment, don’t want any following treatment)