Heat -

the energy that is transferred from one body to another because of a temperature difference between the bodies.

Physiological Effects -

- Increased plasticity of collagen
- Increased elasticity of capsule and synovium
- Decreased viscosity of synovial fluid
- Decreased pain via decreased spasm, ischemia, counter-irritant, endorphin release
- Decreased muscle spasm
- Increased capillary permeability
- Vasodilation
- Malignant cells are more sensitive to heat

Therapeutic Effects -

- Increased extensibility of collagen
- Decreased joint stiffness
- Decreased pain
- Decreased muscle spasm
- Assists in resolution of inflammatory infiltrates, edema, and exudates
- Increased local blood flow
- Cancer therapy

Indications -

- Collagen contracture
- Joint stiffness
- Pain
- Muscle spasm
- Inflammation
- Cold weather injuries - gentle, rapid warming

Contraindications -

- Anesthetic area
- Obtunded patient
- Inadequate vascular supply
- Hemorrhage and acute injuries
- Malignancies without temperature monitoring
- Reproductive organs
- Developing fetus

Methods of Application -

- Hot Packs
- Paraffin
- Fluidotherapy
- Hydrotherapy
- Moist Air
- Radiant Heat (Infra-red, Ultra-Violet)
- Microwave Diathermy
- Shortwave Diathermy
- Ultrasound