Lecture 6 - Hot and Cold Flashcards
define pain
- unpleasant sensory and emotional experience associated with actual or potential tissue damage
what are pain receptors?
- aka nocioceptors
- sensitive to mechanical, thermal and chemical
what are afferent nerves?
- fibres that carry information from nocioceptors towards the spinal cord
what are the two types of pain signals?
- A delta
- C fibres
what are A delta signals?
- myelinated
- fast pain (reflexes)
- large diameter
- touch, pressure, and temperature
- located in skin
what are C fibres?
- 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)
what are the steps of gate control?
- 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)
what are the types of A-beta input?
- pressure = rubbing/massaging
- vibration = tapping body to release opiates and close gate
- position sense = shaking finger (AROM/PROM)
what happens when A fibres accommodate to constant input?
- site under nerve stimulation shows a decrease in excitability
- no longer receiving sensation to the body
- rise in threshold
what is the hunting response?
- after 10-15 minutes of cold treatment, the blood flow will fluctuate
- cold-induced vasodilation (CIVD) occurs
what does the body’s response to cold/ice/cryotherapy depend on?
- 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)
what is happening to tissue in acute injuries?
- tissue injury (primary and secondary)
- cell death due to hypoxia
- increased bleeding to the area (bruising)
- pain
- swelling/edema (cell death from no oxygen)
what are the physiological responses to cryotherapy?
- decreased muscle guarding
- decreased blood flow
- decreased capillary permeability
- decreased metabolic rate
- decreased collagen elasticity
- increased joint stiffness
- edema?
- decreased pain perception
why might ice not be the best idea?
- inflammatory/destructive phase is necessary
- may slow down healing during the first stage of healing (3-7 days)
why is ice a good idea?
- good for pain (myelination)
- decreases swelling when combined with exercise
- improvement in function with exercise
- maintains cell viability (decreased chemical reactions)
what does the body’s response to heat/thermotherapy depend on?
- 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)
what are the physiological responses to thermotherapy?
- 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
what is the inflammation/destruction phase?
- 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
what does peace and love stand for?
- protection
- elevation
- avoid
- compression
- education
- load
- optimism
- vascularization
- exercise
what does police stand for?
- protect
- optimal
- loading
- ice
- compression
- elevation
what is protection?
- shield, unload and prevent joint movement
- control inflammation and prevent further injury
what is loading?
- replacing rest with balanced incremental rehab
- safe cardio for example (vascularization)
- functional rehab (weight bearing and movement)
what is compression?
- decreases local edema
- disperse edema to increase absorption
- elastic bandage can limit blood flow
what is elevation?
- no reduction of blood flow until 30cm above the heart
- 50 cm = 80% of normal
- 70 cm = 65% of normal
- higher = better
what is optimism and education?
- educate athletes of active process of rehab
- why you do each step
- measure progress
- set goals
what are the clinical pearls of icing?
- 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
what are the goals at the repair/fibroblastic phase?
- laying down tissue (not yet organized or liable)
- protect tissue
- idealize healing environment
- increase blood flow (heat)
- idealize ROM
- gentle strengthening
- proprioception
why is heat good in the fibroblastic and remodeling stages?
- increase blood flow
- promote healing
- decrease spasm
- increase collagen elasticity
- decrease stiffness
- increase ROM (without tearing)
what are the goals of the remodelling/maturation phase?
- 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)