Thermal Agents Heat Flashcards
Name the general uses for heat.
- Control pain
- Increase circulation
- Facilitate tissue healing
- Promote relaxation
- Decrease muscle spasm
- Decrease tissue tightness and joint stiffness
- Prepare stiff joints and tight muscles for exercise
How does heat affect tissues?
There is an increase in tissue temperature which changes the viscoelastic properties of the collagen and tissues. Heat increases the effects of passive stretching.
What temperature do you need to provide a therapeutic effect?
Tissue temp should be elevated to 104-113 degrees F
How much does cell activity and metabolic rate increase due to heat?
2-3 fold for each 50 deg F
What does an increase in cell activity and metabolic rate lead to?
It increases oxygen uptake by tissues. This makes more oxygen available for tissue repair.
At what point will tissue burn?
113 deg F to 122 deg F
True or False
Heat causes vasoconstriction.
False!
Increased tissue temp causes vasodilation and increased blood flow
If you want to heat muscle should you use a heating pad or exercise?
Exercise will heat muscle better because skin blood flow and intramuscular blood flow are controlled by different mechanisms. You could put a heating pad on someone and have them do exercise, this would have an additive effect.
What is vasodilation of the skin controlled by?
- An axon reflex
- Release of chemical mediators
- Local spinal cord reflexes
True or False
Skeletal muscle blood flow is under metabolic regulation.
True!
Explain consensual heating.
Consensual heating is when a part of the body is heated and there is an increase in blood flow to distal extremities. If I heat someone’s back, they will get an increase in blood flow to their feet.
What are the neuromuscular effects of heat?
- Elevate pain threshold
- Alter nerve conduction velocity
- Change muscle spindle firing rates
How does heat lessen muscle spasms?
Decreases gamma efferent activity which would reduce the stretch on the muscle spindle, and that reduces afferent firing from the spindle.
This indirectly reduces the alpha motor neuron firing and reduces muscle spasms.
If you want to decrease someone’s neck pain, would you use heat or ice?
Heat. People tend to tolerate cold better on their extremities than on their trunk.
You want to explain how heat affects someone’s connective tissue. What would you say?
- Increases elasticity
- Decreases viscosity
- Decreases joint stiffness
- Increase muscle flexibility
