Thermotherapy Flashcards
What is thermotherapy?
The therapeutic application of heat
What is thermotherapy used to do?
Control pain
Increase tissue extensibility
Increase circulation
What are the effects of thermotherapy?
Hemodynamic effects
Neuromuscular effects
Metabolic effects
Altered tissue extensibility
What are the hemodynamic effects caused by thermotherapy?
Vasodilation
What is vasodilation?
Increase in blood flow occurs mostly where heat is applied but also occurs in more distal and deeper vessels
What are the local hemodynamic effects of thermotherapy?
Superficial heat stimulation of cutaneous thermoreceptors -> release of bradykinin and NO-> smooth muscle relaxation -> vasodilation
What are the global hemodynamic effects of thermotherapy?
Cutaneous thermoreceptors also project to the DRG, where they synapse with sympathetic neurons in the lateral grey horn of the spinal cord, inhibiting firing and decreasing sympathetic output -> smooth muscle contraction
How is vasodilation a safety mechanism?
It occurs in response to increase in tissue temperature to protect the body from overheating
where would we place a hot pack for someone with peripheral artery disease?
More proximal to the problem to improve vasodilation dismally and avoid burns at the problem
Where would we apply a hot pack for a patient with a diabetic ulcer?
Proximal to the ulcer to improve vasodilation dismally without irritating that ulcer
can we increase blood to muscles with heat?
Changes in skeletal muscle blood flow is dictated by metabolic factors > sympathetic activity
Superficial heating agents only increase superficial tissues
What may be a better intervention to increase blood flow to muscles?
Therapeutic exercise or ultrasound
what are some neuromuscular effects of thermotherapy?
changes in nerve conduction velocity (increases) and firing rate
increased pain threshold
changes in muscle strength
would a patient with multiple sclerosis or any demyelinating disease respond well to thermotherapy?
NO it could make them worse and more fatigued because heat shortens the duration of opening of sodium channels at nodes of Ranvier
how does thermotherapy increase pain threshold?
increased activity of superficial thermoreceptors which can have “gating” effect at spinal cord level and increase in blood flow
what effect on muscle strength does thermotherapy have?
there is a decrease in muscle strength for 30 minutes after applying heat, then muscle strength increases above pre-treatment levels for approximately 2 hours after
what is the metabolic effect of thermotherapy?
increase in tissue temperature shifts oxygen hemoglobin dissociation curve to the right making more oxygen available for tissue repair
how can thermotherapy alter tissue extensibility?
increase in collagen extensibility
tissue temp should be maintained at 40-45º for 5-10 minutes
can only heat superficial tendons or muscles
which is a more effective combo:
just heat
just stretching
heat and stretching combined
heat and stretching combined
what are the clinical indications for superficial heat?
pain control
increase ROM
decrease joint stiffness
accelerate healing
how can thermotherapy help pain control?
gating of pain through activation of cutaneous thermoreceptors
increase in blood flow via vasodilation
heat modalities are just relaxing and we know pain can be influenced by stress
not recommended for acute inflammation but has been shown to be effective for acute low back pain
how can thermotherapy help increase range of motion and decreased joint stiffness?
increasing soft tissue temperature increases tissue extensibility
decrease in joint stiffness
what is the best temperature to increase tissue extensibility?
40-45º C
104-113º F
how can thermotherapy help accelerate healing?
increase in circulation and increased oxygen availability to tissues
most beneficial during the proliferative or remodeling stage of healing
if edema is present, proceed with caution as heat can increase edema