Electro 1-1.pdf

At The End of this Lecture, The Student Should be Aware of the following Items:  Define electro-physical agents.  List and describe the different forms of energy used with therapeutic modalities.  Enumerate modes of energy transfer.  Energy Electrophysical A...

At The End of this Lecture, The Student Should be Aware of the following Items:  Define electro-physical agents.  List and describe the different forms of energy used with therapeutic modalities.  Enumerate modes of energy transfer.  Energy Electrophysical Agent Thermal  Thermotherapy  Cryotherapy  Hydrotherapy Electromagnetic  Shortwave diathermy  Low-level laser therapy  Ultraviolet Electrical  Neuromuscular electrical  Electrical stimulation for tissue stimulation healing and repair  Transcutaneous electrical nerve  Iontophoresis stimulation Mechanical  Spinal traction  Ultrasound  Limb compression  Extracorporeal shock wave  Continuous passive motion therapy  It is a therapeutic type of treatment in which using the benefits of heat energy to deliver its effect over skin surface areas on the body as a generally or local body area as the following:  Promotes an increase in blood flow.  Facilitate tissue healing.  Relaxes skeletal muscles and decreases spasm.  Decreases pain.  Prepares joints, capsular structures, muscles, and other soft tissues around joints for stretching, mobilization, and exercise.  Superficial heating Like:  Deep heating Like:  Hot packs (Moist Heat).  Paraffin Wax.  Infrared. (Dry Heat).  Short wave diathermy.  Therapeutic Ultrasound.  Is a therapeutic type of treatment in which using the benefits of cooling energy effect in order to decrease tissue temperature to induce therapeutic and physiological responses.  Reducing blood flow and tissue metabolism thus leads to decrease bleeding and acute inflammation following any injury or tissue disruption.  Desensitizing effect on the peripheral afferent nociceptors thus Reducing of pain.  Traction Distraction forces to reduce compression of adjacent segments, such as articular surfaces of joints. Reducing pressure on anatomical structures, such as nerves, blood vessels, and joint capsules.  Traction may be used to: Decrease pain and increase range of Increase blood flow, and reduce muscle guarding motion. spasm. Improve functional ability. Stretching and induce relaxation  Compression Techniques  Applied to: Prevent, attenuate, or reverse swelling that may follow soft tissue injury. Alter formation of scar tissue during the proliferation and maturation phase of scarring.  Types of compression techniques Wraps. Stockings. Pressure garments  Energy moves from an area of high concentration to an area of lower concentration by energy carriers, such as;  Mechanical waves.  Electrons.  Molecules.  Photons.  Heat transfer between two substances can occur through four different modes:  Conduction  Convection  Radiation  Evaporation  Conversion  The result is that heat can be added (thermotherapy) or removed (cryotherapy) from the soft tissues  occurs through the physical contact between two solid substances of different temperatures.  occurs from the warmest to the coldest substance.  In thermotherapy, the higher kinetic energy of the warmer substance (the agent) increases, the lower kinetic energy of the colder substance (tissue) through microscopic molecular collisions. The resulting heat added to the tissue increases its temperature.  In cryotherapy, the higher kinetic energy of the warmer substance (tissue) increases, the lower kinetic energy of the colder substance (the agent) through the same mechanism. The tissue thus loses heat, whereas the cryoagents gain heat.  In hydrotherapy, the heat transfer is also achieved by conduction with the colder or warmer water in contact with the skin.  Physical contact between a gaseous or fluid medium (such as air and water) and a solid substance, both at different temperatures.  Free convection is the heating of the solid substance induced solely by the temperature difference between the two substances.  Forced convection, on the other hand, is caused when the motion of the fluid or gas is imposed externally by means of a fan (Fluidotherapy) or a turbine (hydrotherapy). (Whirlpool) use either free (still water) or forced (turbine) convection to transfer their energy to tissues.  Is the propagation of energy in the form of rays or waves.  It occurs in the air space between the emitting source and the absorbing solid.  Direct transfer of heat from material at the higher temperature to the material at the lower temperature.  Emission of electromagnetic radiation from heated objects.  The use of shortwave diathermy, Infrared lamps and microwave diathermy are good examples of heat transfer by radiation.  Transformation of a liquid to a gaseous state.  When a vapocoolant is sprayed on the skin, as in cryotherapy , the liquid molecules  vaporize from the skin surface.  The heat to produce this transition is extracted from the skin tissue, which is thus cooled. Conversion of a non-thermal form of energy into heat.  Does not require direct contact.  Ultrasound therapy and diathermy. sufficient amount of electromagnetic energy Lows governing the applicator position and its must first be delivered and then absorbed by the relation to the treated skin surface. targeted tissue  Arndt-Schultz Law-Dosage  Inverse Square Law-Divergence  Grotthuss-Draper Law-Absorption  Lambert’s Cosine Law-Reflection  1. Arndt-Schultz Law-Dosage No physiologic or therapeutic effect (or response) will occur in the target tissues if the amount of radiating energy delivered at the applicator–skin interface (dose) is insufficient to cause adequate energy absorption within the target tissue (response). Small to moderate levels of energy absorption stimulate the therapeutic effects, whereas stronger doses may be toxic and even lethal for the exposed tissues. This law dictates the relationship between dose and response.  2. Grotthuss-Draper Law-Absorption To have any physiologic or therapeutic effect, or response, the tissues must absorb the radiating energy. This law dictates the relationship between energy absorption and penetration (or transmission).  Higher-frequency, shorter-wavelength light has a tendency to be absorbed at a more superficial level. Absorption is inversely related to penetration (or transmission). The greater the absorption of energy by superficial tissues, the lesser the penetration (or transmission) of energy in the deeper tissues. Conversely, the lower the absorption in superficial tissues, the greater the penetration of energy in the deeper tissues.  3. Inverse Square Law-Divergence The intensity (I) of radiation, or power, observed from a divergent, or non-collimated, radiating source decreases with the square of its distance (D) from the target tissue, Formula: I = 1/D2 The energy twice as far from the source is spread over four times the original area (A), resulting in one fourth, or 25%, of the intensity per area. Tripling the distance (D3) from the source will further reduce the intensity per area to only one ninth of the original intensity per area. This law dictates the inverse relationship between distance of exposure and energy exposure per surface area in cases of non-collimated radiating sources.  doubling (D2) the original distance between the source and the target tissue (i.e., from D1 to D2) reduces the intensity of energy to one quarter (or 25%) of its original value per surface area radiated  (I = 1/1 = 100%; I = 1/22 = 1/4 = 25%).  A collimated radiating source, such as a laser, does not obey this law.  4. Lambert’s Cosine Law-Reflection To obey this law, practitioners must try to keep the applicator surface parallel as possible with regard to the treated area. In other words, they must align the beam of radiation as perpendicular to the treated surface as possible. The greater the incident angle relative to normal, the lesser the amount of radiating energy available to the tissues because of wave reflection. Cosine Law The intensity of radiation varies with the cosine of the angle of incidence. Effective energy= energy X cosine of the angle of incidence Right angles have the highest level of penetration and least reflection.