Heat

superficial heat can get up to

1in deep

principle of heat

heat it up, then do something with it

tissue stays more extensible for how long after heat application

about 4 minutes

heat therapy methods

hot packs, paraffin, fluidotherapy, infrared (not anymore), whirlpool

therapeutic range for thermotherapy

104-113F

>113F can lead to

catabolism and cell death

main energy transfer types for thermotherapy

conduction, convection and radiation

conduction is directly proportional to

temperature gradient, duration of application, thermal conductivity of the tissue

thermal conductivity of tissue order

skin > muscle > fat

for heat conduction, instead of an insulator we want

insulation rather than conduction - use a dry towel

layers of towel for heat therapy

8-12 layers to protect skin

body weight positioning with heat therapy

body part should be supporting heat pack, not placing body weight on pack (decreases insulation)

conduction of heat is inversely proportional to

thickness of coupliong medium

hydrocollators water temp

158-168F (do not touch the water)

hot packs transfer heat via

conduction, stored in hot water, coupling medium to avoid damage

hot pack and what activity is ok

concurrent stretching

whirlpool heat transfer is via

conduction and convection (turbine and pressure... gate theory)

whirlpool may be combined with what activity

therapeutic activity or aquqatic therapy

whirlpool issues

contamination and costs with cleaning and heating water

paraffin heat transfer is via

conduction, goes 1-2cm deep

paraffin temp

113-122F

why is it safe to touch paraffin wax and not the hydrocollater water

paraffin has a lower thermal conductivity and lower specific heat, decreasing its ability to transfer energy to the bare hand

paraffin is good for

distal limbs and contoured areas

first dip of paraffin should be

deeper, followed by more shallow dips, 6-12 layers, then period of 30min retention outside of bath (can wrap)

fluidotherapy

contains natural cellulose circulating in dry warm air

fluidotherapy heat

130F, no humidity (can control heat and airflow)

activity with fluidotherpay

therapeutic activity

fluidotherapy heat transfer via

convection

fluidotherapy stimulates

thermo and mechanoreceptors (heat and movements)

effects of fluidotherapy

thermal, desensitization of hypersensitivie tissue, prevents edema (if limb is in horizontal position)

fluidotherapy disdvantages

expensive, cannot treat proximal joints, slippery from cellulose spillage, large

thermotherapy effects

vasodilation, neuromusclar effects, metabolic effects, increased tissue extensibility

vasodilation with heat therapy

improves healing and repair, removes inflammatory compound activating nociceptors

reflex vasodilation

heat triggers reflex activation of sympathetic cholinergic fibers and affects deeper tissue (greatest tissue temp 1-2 cm)

neuromuscular effects of heat therapy

increase in temperature decreases firing rate of type 2 muscle spine, increases type 1b and GTO, and decreases alpha motor neurons

overall neuromuscular effect of heat therapy

decreases muscle activity and spasms which can reduce pain, increases pain threshold (takes over fiber conduction info) (gate)

muscle strength and endurance after heating may be

decreased for the initial 30 min following (keep muscles warm with activity instead)

metabolic effects of heat

increases enzymatic activity, O2 uptake, accelerates healing and detruction of articular cartilage with RA

use caution with acute inflammatory disorders

heat may contribute to inflammatory process (dont add heat during RA flare up, ok without flare)

tissue extensibility with heat

increases collagen extensibility, acheiving greater soft tissue length and reducing risk of tissue tear

tissue extensibility is optimal at

104-113F for 5-10min

you should stretch when using heat

during and right away after (4 min of extensibility increase)

thermotherapy indications

pain, joint stiffness, tissue healing (at end stage), psychological

heat directly

vasodilates, increases thermoreceptor activity and decreases joint viscosity

application of heat precautions

ask about sensitivities, check on patient, 20 min max, stop if needed (keep bell out, etc)

contraindications to heat therapy

acute injury or inflammation, open draining wound, thrombophlebitis, impaired sensation/mental cognition, malignancy, pregnancy,