Thermal Modalities
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Common procedures
o Inspect the area and clear of potential hazards.
o Use a stockinette for hygiene
o Elevate the limb being treated
o Temperatures = 10 C to 15 C (50-59 F)
o Apply colling for 15 min every couple of hours
o Inspect area after treatment
Metabolic Effects
o Heat increases metabolic rate 2-3 fold for every 18 F
o Increases arteriolar dilation/blood flow locally
o Tissue damage can occur as temp rises above 113 F
Vascular Effects
o Increase in tissue temp is usually associated with vasodilation and an increase in blood
flow
 Increase in nutrients and leukocytes
 Increase in capillary permeability.
Neuromuscular effects
o Heat
 Decreased pain
 General relaxation
 Decreased skin impedance
 Strength initially decreases and gradually increases over 2 hours
o Cold
 Decreased pain
 Decreased neuronal firing
 <5 min increase isometric strength
 >30 decrease isometric strength initially then increase 1 hour later
Ultrasound
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Attenuation: the absorption, reflection, and refraction of sound
o As frequency increases so does the attenuation
o 1 MHz penetrates deeper than 3 MHZ
Types
o Continuous
o Pulsed
 Duty cycle = pulse duration/pulse period
Thermal Effects
o Increase collagen extensibility
o Alterations in blood flow
o Changes in nerve conduction velocity
o Increase pain threshold
o Increase local metabolism
Phonophoresis
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Common agents: hydrocortisone, dexamethasone, lidocaine, and methyl salicylate
3 MHz, 20% duty cycle, 0.5 W/cm2, 5-10 min