electrophysical agent 1

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Electro physical agents



Structure and Properties of Matter

� Matter means material such as Pen, Rod,ect.

� Material or matter is made up of atoms.

ATOM:

� Atom is defined as the smallest indivisible part

of matter.



Structure of atom

� The Atom can be described having a central nucleussurrounded by cloud of electrons revolving in definite orbits.

� The Nucleus: This is the central part of the atom, the two

most important particles are the proton and the neutron.

� Proton: it is positive charged particle present in the nucleus,because of this the charge of nucleus is positive.



Structure of atom



Structure of atom

� Neutron it is neutrally charged particle

present in the nucleus.

�

Electron negative charged particles revolvingin orbits around the nucleus.

� In neutral atom their number is equal to

number of protons.



Formation of Compounds

� A Compound is a substance formed by the

union of two or more elements.

� Atoms combine to form molecule.

� Molecules combine to form elements.

�Elements combine to form compounds.Example: Sodium chloride (Common Salt)



Electro Magnetic Radiation

- when ever any object is heated the electrons

from lower orbit takes up energy and goes to

higher orbit.

- After sometime the electrons return back to its

original orbits, while coming back they loose

energy in the form of light called as electron

magnetic radiation.



Electro Magnetic Radiation



Different kinds of rays

� X-rays.

� Infrared

�Visible rays-rays coming from sun ,in the earlymorning.

� U V rays

�Gamma rays

� Radio rays



Different kinds of rays



Forces

� Force is defined as push or pull exerted by one object

on other object.

� In a molecule we have two types of forces

- Cohesive force.- Kinetic force.

� Cohesive force-attractive force between two atoms.

� Kinetic force-force required to move atoms, or the

force with which atom can move.



Cohesive force - Kinetic force.



States of matter

2.Liquid: Cohesive force is present and it is less,

kinetic force is increased, liquid will take the

shape of object.

If energy is supplied to liquids they transform

into gases.

3.Gas : Cohesive force is very less, kinetic force

is more.



States of matter

example: Ice (solid) to water (liquid) to vapor

(gas).



Latent heat:

Latent heat:� The energy required to change from one state

to another state is called as latent heat.



Electrical charges

� Atom have properties of losing or gaining

electrons.

�

When an atom of an element loose electron itbecomes positive (cation).

� When an atom of an element gains electron it

becomes negative (anion).



Transmission of heat

Transmission of heat takes place in three forms

1. Conduction.

2. Convection.3. Radiation.




1. Conduction: takes place

in case of metals. Heat

transfer from high

temperature to low

temperature.

s




2. Convection: transmission

of heat that is taking place

in liquids.

The electrons at bottom are

heated and they will go up,

the atom at the top will

come down.




3. Radiation: Transmission of heat taking place

in gases is called as radiation.



Physical Effects of heat

1. Expansion: expansion is the result of

increased kinetic energy producing a greater

vibration of molecules.

2. Change in state: heat causes changes from

one state to another.

solids to liquid and liquid to gas.

3. Acceleration of chemical reaction: heat

increases the chemical reaction.




4. Electron magnetic radiation: when ever any

object is heated the electrons from lower orbit

takes up energy and goes to higher orbit after

sometime the electrons return back to its

original orbits, while coming back they loose

energy in the form of light called as electron

magnetic radiation.




5. Decrease in viscosity: heating increases the

kinetic movement of the molecules and

reduces cohesive forces this makes fluid less

viscous.



Electricity



Introduction

� Electricity: Flow of electrons is called as electricity.

� Conductors: These are the elements whose atoms

have free electrons in their outer orbits.

� They allow the electrons to pass through them.

� Electric current pass through conductors easily.

Example: Metals like Iron, human being.



Introduction

� Non conductors or insulators: Elements in

which the atoms have completely filled

electrons In their outer orbit.

� They will not allow the electrons to pass

through them.

� Electric current can not pass through

insulators. Example: wood, clothes.



Static Electricity

� Static Electricity: When the charges are held on thesurface of a body it is called as static electricity.

Production:

� The simplest way of producing a static electriccharge is to rub two suitable materials together.

� If two insulators such as Glass and Flannel arerubbed together, a positive charge is produced on

the flannel and a negative charge on the glass.



Static Electricity

� This is because electrons are transferred from

the superficial atoms of the flannel to the

surface of the glass.

� As the materials involved are insulators, the

charges are held on the surfaces of the objects

and spread themselves evenly over the

surfaces.



Static Electricity



Static Electricity

Charged body and its electric field

� The charged body is continually seeking to attain

neutral state, if negative by loosing electrons, and if

positive by gaining electrons.

� This creates a zone of influence (electric field).

� This field is made up of lines of force surrounding the

body.



Static Electricity

� They show certainproperties.

- The lines of force are

straight.- Lines of force repel one

another.

- Lines of force pass more

easily through conductorsthan through insulators.



Static Electricity

� Potential: electrical potential is the electricalcondition of the body.

� Bodies with excess of electrons are negative.

� Bodies with less electrons are positive.

� Capacitance: Ability of a body to hold electriccharge.

� It depends on material and surface area of thebody.



Static Electricity

Difference of potential (Potential difference)

� A difference of potential exists between similarbodies charged with different quantities of

electricity.� If a conducting connection is made between two

bodies electrons will flow from the more negativebody to less negative body.

�

The force producing the movement is Electromotiveforce.

� Electrons flow until both objects are at the samepotential.



Current Electricity

Electromotive force (EMF):

The force which causes electrons to move along

a conductor is called as EMF

.Resistance:

The conductor through which electrons have to

flow offers some resistance to their flow.



Current Electricity

Electrical Resistance depends on

- material

- length of the material

- cross sectional area

Magnitude of Current (Intensity);

The intensity or magnitude of current (i) is the rate of

flow of electrons through the conductor per second.



Break Time



Electrical Energy

Anand kumar Anand kumar



All of us agree the importance of electricity in our daily

lives.

But what is electricity?



Electricity!Everything in the world is made up

of atoms. Each atom has smaller

parts in it. One of those parts iscalled electrons. Electrons can

move from atom to atom. When

electrons move quickly from one

atom to another is it calledElectricity!



ELECTRICITY

There are two areas that can be studied

STATIC ELECTRICITY CURRENT ELECTRICITY

This section deals with

stationary charge.This section deals with

moving charge.



Static Electricity

� The build up of an electric charge on the surface of an

object.

� The charge builds up but does not flow.

� Static electricity is potential energy. It does not move. It isstored

- --

--

-

- ++++

+



Examples of Static Electricity

�

Take a comb or plastic pen and ru

b it on almost any pieceof fabric, it will acquire a small electric charge

� If placed near small pieces of paper, they will be attracted



When two objects rub against each other electrons transfer and build up on an

object causing it to have a different charge from its surroundings.

Like the shoes rubbing against the carpet. Electrons are transferred from the

carpet to the shoes.

Examples of Static E lectricity Examples of Static E lectricity



CURRENT ELECTRICITY

Current: The flow of electrons from one place to another.

Measured in amperes (amps)

Electricity that moves«Electricity that moves«



Current Electricity

� There are two types of currents

� Direct current

� Alternating current

� Direct current given ( DC)

charges moving continually in one direction

eg using batteries

� Alternating current given ( AC)

the direction of charge flow is reversing or alternatingdirection continually

eg using mains power at 50 Hz AC



ELECTRIC CIRCUIT

A path that allows electrons to flow from negative to positive



1.series circuit 2. parallel circuit

What is aseriescircuit?

A series circuit is one which provides a single pathway forthe current to flow. If the circuit breaks, all devices usingthe circuit will fail.

There are two types of circuits



What is a parallel circuit?

A parallel circuit has multiple pathways for the current to flow. If

the circuit is broken the current may pass through other pathwaysand other devices will continue to work.



Electricity

� The unit of charge is the coulomb (C)

� The charge on an electron is -1.6x10-19 C

� The charge on a proton is +1.6x10-19 C

� One coulomb is the flow of 6.25x1018 electrons� Electric current is the rate of flow of electrons

� The unit of current is the Ampere (Amp)

� One Amp is the flow of one coulomb in one second



Electrically, materials are classified

as

Insulators Conductors

Semiconductors



� Conductors have a lower resistance.

� Examples: metals, copper, silver.

� Pure water does not conduct well, butwater with dissolved salts does conduct

A conductor is a material that current can pass through easily,A conductor is a material that current can pass through easily,like metalslike metals

C onductorsC onductors



Semiconductors

� Semiconductors allow electrons to flow onlyunder certain conditions eg silicon. For siliconthe conductivity is increased by the additionof small amounts of elements such as arsenic

or boron



Transmission of electricity through

solids,eletrolytes,gasesHeat:Heat:--

Heat is the movement of thermal energy from aHeat is the movement of thermal energy from a

substance at a higher temperature to another substance at a higher temperature to another substance at a lower temperature.substance at a lower temperature.

Heat moves in only one direction:Heat moves in only one direction:

Under normal conditions and in nature, heatUnder normal conditions and in nature, heat

energy will always flow the warmer object to theenergy will always flow the warmer object to the

cooler objectcooler object



How HEAT moves

� Thermal energy in the form of heat can move

in three ways:

1. Conduction (solids)

2. Convention (liquids and gases)

3. Radiation



Conduction

� The transfer of heat from one particle of matter to another by direct particle contact.

� Conduction occurs primarily in solids because

the particles are tightly packed together.� The particles themselves DO NOT change

positions.



Radiation

� Radiation: the transfer of (thermal) energy byelectromagnetic waves.

� Radiation does not require matter to transferthermal energy.

� Example: ± Charcoal grill ± Hot tin roof ± Burner on a stove top



Household Electricity

� Cords

� Computers

� TV

� Microwave

� Stove

What are some types of household electricity?What are some types of household electricity?



Safe Use Of Electricity

� Dont pull cords

� D

ont put metal in anelectrical appliance



How Electricity Impacts Today's

Life

We use electricity for

light, heat,

transportation,

everything!



Dangers of static and

current electricity

Precautions Precautions



� Electricity is essential to

modern life

�Some employees work with electricity directly

� Some indirectly

�Electricity is a seriousworkplace hazard

Dangers of static and current Dangers of static and current

E lectricity E lectricity



Electrical Shock

� A sudden and accidental stimulation of the

bodys nervous system by an electrical current

� Current will flow through the body

when it becomes part of an electrical circuit



Other Injuries

� Burns

� Falls

� Injuries when machinery starts suddenly



Electrical Burns

� Current passing through tissue generates

extreme heat

� Skin damage at entry and exit

� Internal tissue damage

� Result from arcs or flashes

�

Thermal burns from overheated wires orequipment or fires



Falls

� Initiated by a shock

� Muscles contract involuntarily

� Worker can lose balance and fall



Machinery Injuries

� Unexpected activation

� Shock

�

Pinch� Crush

� Shear



A GOOD T HING TO KEEP IN MIND!

Precautions Precautions



S AFETY SHIELDS ARE EYE INSURANCE!



S AFETY SHOE S ARE NOT FOR

DEFEAT!

HEARING PROTECTION IS FOR



HEARING PROTECTION IS FOR

WINNERS!



Thermal Energy

� Units of heat and temperatures

� Physical effects of heat

� Transmission of heat

Anand kumar Anand kumar

Temperature



Temperature

1. Temperature is related to theaverage kinetic energy of the

particles in a substance.

Cup gets cooler while



Heat

a. The flow of thermal energy

from one object to

another.

b. Heat always

flows from warmer

to cooler objects.Ice gets warmerwhile hand gets

cooler

Cup gets cooler whilehand gets warmer

Units of Heat



83

Units of Heat

� The SI unit is the joule (J),

which is equal to Newton-metre (Nm).

�

Historically, heat was measured in terms of theability to raise the temperature of water.

� The calorie (cal): amount of heat needed to

raise the temperature of 1 gramme of water by1 C0 (from 14.50C to 15.50C)



Heat TransferConduction, Convection, and Radiation



Review: Temperature

� Temperature is:

± The quantity that tells how hot or cold something

is compared with a standard

± A measure of the average kinetic energy of themolecules of a substance

� Temperature IS NOT energy

±If something has a higher temperature, itsmolecules have more energy, but temperature is

not the same thing as energy



Review: Thermal Energy

� Thermal Energy is:

± The total energy (kinetic plus potential) of the

particles that make up a substance.



Review: Heat

� Heat is:

± The thermal energy that flows from an object at

higher temperature to one at lower temperature,

commonly measured in calories or Joules.

� Heat is exchanged until thermal equilibrium is

reached



A Comparison

Temperature Thermal

Energy

Heat

Measuresaverage

kinetic energy.

The sum of allthe

kinetic

energies.

The flow of thermal

Energy.



Conduction

Conduction: How does this method




work?

� Conduction takes place within materials and

between different materials that are in direct

contact.





work?

� Conduction is explained by collisions between atomsor molecules

± Warmer atoms move more violently (they have moreenergy). These warmer atoms bump into nearby atoms

and transfer energy, resulting in an increase in the motionof the nearby atoms.





work?

� Free electrons that drift through the metal jostle and transfer energy by colliding withatoms and other free electrons



Conduction: What moves?

� Conduction involves the transfer of energy

from molecule to molecule; energy moves

from one place to another but molecules do

not.



Conduction: Heat Conductors

� Materials that conduct heat well areknown as heat conductors.

± Metals are the best heat conductors sincemetals have loose outer electrons

± If you touch a piece of metal that is at roomtemperature it often "feels cold." This isbecause metal is a good conductor of heat.It quickly conducts heat away from yourbody.



Conduction: Heat Insulators

� Poor conductors of heat, such as styrofoam and air,are called good insulators.

± Liquids and gases are in general good insulators. Porousmaterials with lots of small spaces are good insulators.

± A blanket on your bed does not provide your body withheat. It just slows the conduction of your body heat to thecolder air.

± Insulation delays heat transfer, it can not prevent it!



Convection



Convection: How does this method



Convection: How does this method

work?

� When a fluid is heated, itexpands and becomes lessdense; since it is less dense, itrises.

�

Warmer fluid floats on top of cooler fluid.

� Cooler fluid then moves to thebottom and the processcontinues.

� Convection currents keep a

fluid stirred as it is heated.



Convection: What Moves

� Convection involves the movement of a fluid;

if there is not a fluid, convection cannot occur.



Convection: Example

� Convection currents stir the atmosphere andproduce winds.

� Convection currents are produced by unevenheating of the air near the surface of the earth.



Convection: Example

� Land warms and cools more quickly than water. Thusconvection currents are often evident at the shore insea breezes and lands breezes.

d



Radiation



di i h



Radiation: What Moves

� With radiation, only energy moves from the

warmer object to the cooler object.

R di i W l h E i d



Radiation: Wavelengths Emitted

� All objects continually emit radiant energy in amixture of wavelengths. Objects at lowertemperatures emit longer waves and objects athigher temperature emit waves of shorter

wavelength. Objects of everyday temperatures emitwaves mostly in the longer wavelength end of theinfrared region.



Radiation: Absorption and Reflection

are Opposite Processes

� A good absorber of radiant energy reflects very little

radiant energy and appears dark. A perfect absorberreflects no radiant energy and appears perfectlyblack.

� Good reflectors of radiant energy are poor absorbers.

Light colored objects reflect more light and heat thandarker colored objects. This is why wear lightercolored clothing in summer to stay cool.

H T f f M



Heat Transfer for a Mouse



What Is the Electromagnetic Spectrum



What Is the Electromagnetic Spectrum

(EM)?� The electromagnetic spectrum is the complete

range of electromagnetic waves placed in

order of increasing frequency.



VISIBLE LIGHT

(part of EM spectrum)

The Electromagnetic Spectrum



More than meets the eye!

Examples from Space!



W l th



Wavelength

� The distance from one wave crest to the next

� Radio waves have longest wavelength and Gamma rays

have shortest!

W l th U it



Wavelength Units

� Meters (like on last slide and in book, p. 613)

± More commonly in nanometers (1 nm = 10-9

meters)� Angstroms still used

± Named for Swedish Astronomer who first named

these wavelengths

± 1 nanometer = 10 Ao

How light or electromagnetic radiation is



g g

used in Astronomy

� Astronomers use a tool called aspectroscope to separate starlight into itscolors in this way, they can tell what a staris made of, its temperature, luminosity andso on

� Astronomers can look at astronomical

objects at different wavelengths



Spectra of a

Star



WHITE LIGHT



WHITE LIGHT

Adding color makes WHITE Deleting color

makesBLACK



MANY COLORS = WHITE



�Reflection�Retraction

�Absorption�Radiation laws



HOW LIGHT MOVES

Straight Line unless altered by what moving in.

LIGHT SCATTERS AS GOES



LIGHT SCATTERS AS GOES

Light scatters and looses energy the furtheraway from its source.

SCATTERING



SCATTERING� Light released and spreads in all directions.

± Why room is even with light.

± Sky blue: shortest wavelengths, spread more.



R EFLECTIONR EFLECTION

REFLECTIONREFLECTION



REFLECTIONREFLECTION

Light bounces off surface at same angle ithits.



ABSORPTION

ABSORPTION



ABSORPTION

� LIGHT IS TAKEN IN BY AN OBJECT (MATTER)AND HOLDS IT.

� ENERGY TRANSFERRED FROM LIGHT TO HEAT.

� AIR PARTICLES DIMINISH LIGHT.



INTERACTS

WITH MATTER

TRANSMISSION

� Light goes straight unless changes what it

travels through.

� Travels through matter:

gases (air)

liquids (water)

solid (glass)

TRANSMISSION



Terms for mediums

� Transparent : allows all light through.

� Translucent : allows some light through.

� Opaque : allows no light through.

Wh Li ht St ik Obj t



When Light Strikes an Object

When light strikes

an object, the lightcan be reflected,transmitted, or

absorbed.

REFRACTION



REFRACTION

� The change in direction and speed.

� Moving from water to air, light changesangles and speed of travel.

Refraction of Light



Refraction of Light

When light rays enter a

medium at an angle,

the change in speedcauses the rays to

bend, or change

direction.



LIGHTLIGHT -- WHAT WE SEEWHAT WE SEE



LIGHTLIGHT WHAT WE SEEWHAT WE SEE�LIGHT - energy by wavelengths at a level we can see.

� EM Spectrum- variety of wavelengths and frequency.

Light is small band within.



Heat and Internal Energy� Internal EnergyU is the total energy associated with the



� Internal EnergyU is the total energy associated with themicroscopic components of the system

± Includes kinetic and potential energy associated with therandom translational, rotational and vibrational motion of theatoms or molecules

± Also includes the intermolecular potential energy

± Does not include macroscopic kinetic energy or externalpotential energy

� Heat refers to the transfer of energy between a systemand its environment due to a temperature differencebetween them

± Amount of energy transferred by heat designated by symbol Q

± A system does not have heat, just like it does not have work(heat and work speak to transfer of energy)

Units of Heat� The historical unit of heat was the calorie



The historical unit of heat was the calorie

± A calorie is the amount of energy necessary to raise the

temperature of 1 g of water from 14.5°C to 15.5°C

± A Calorie (food calorie, with a capital C) is 1000 cal

� Since heat (like work) is a measure of energy transfer, its

SI unit is the joule

± 1 cal = 4.186 J (Mechanical Equivalent of Heat)

± New definition of the calorie

� The unit of heat in the U.S. customary system is the

British thermal unit (BTU) ± Defined as the amount of energy necessary to raise the

temperature of 1 lb of water from 63°F to 64°F

More About Heat

� Heat is a microscopic form of energy transfer involving



� Heat is a microscopic form of energy transfer involvinglarge numbers of particles

� Energy exchange occurs due to individual interactions of the particles

± No macroscopic displacements or forces involved

� Heat flow is from a system at higher temperature to one

at lower temperature ± Flow of heat tends to equalize average microscopic kinetic

energy of molecules

� When 2 systems are in thermal equilibrium, they are at

the same temperature and there is no net heat flow� Energy transferred by heat does not always mean there is

a temperature change (see phase changes)



Ideal Gas Law



Ideal Gas Law

PV=nRTZ

n = Mass

R = Universal gas constantT = Temperature

Z = Supercompressability

(P1V1/T1)Z1=(P2V2/T2)Z2

Ideal Gas Law



� An Ideal Gas (perfect gas)is one which obeysBoyle's Law and Charles' Law exactly.

� An Ideal Gas obeys the Ideal Gas Law (General gasequation):

PV = nRTwhere P=pressure, V=volume, n=moles of gas,T=temperature, R is the gas constant which isdependent on the units of pressure, temperatureand volume

Boyles Law



y

� At constant temperature, the volume of agiven quantity of gas is inversely proportionalto its pressure : V 1/PSo at constant temperature, if the volume of agas is doubled, its pressure is halved.ORAt constant temperature for a given quantity

of gas, the product of its volume and itspressure is a constant : PV = constant, PV = k



At constant temperature for a given quantity of gas :

PiVi = PfVf where Pi is the initial (original) pressure, Vi is its initial

(original) volume, Pf is its final pressure, Vf is its final

volume

Pi and Pf must be in the same units of measurement(eg, both in atmospheres), Vi and Vf must be in the

same units of measurement (eg, both in litres).



All gases approximate Boyle's Law at high

temperatures and low pressures. A hypothetical gas

which obeys Boyle's Law at all temperatures and

pressures is called an Ideal Gas. A Real Gas is onewhich approaches Boyle's Law behaviour as the

temperature is raised or the pressure lowered.

Boyles Law



y

P1V1=P2V2



At constant pressure for a given quantity of gas : Vi/Ti = Vf/Tf where Vi is the initial (original) volume, Ti is its initial (original)

temperature (in Kelvin), Vf is its final volme, Tf is its final

tempeature (in Kelvin)

Vi and Vf must be in the same units of measurement (eg,both in litres), Ti and Tf must be in Kelvin NOT celsius.

temperature in kelvin = temperature in celsius + 273

(approximately)



All gases approximate Charles' Law at high temperaturesand low pressures. A hypothetical gas which obeys

Charles' Law at all temperatures and pressures is called an

Ideal Gas. A Real Gas is one which approaches Charles'

Law as the temperature is raised or the pressure lowered

Charles Law



V1/V2=T1/T2

P1V1/T1=P2V2/T2

Latent Heat



When a solid melts or a liquid boils, energy must

be added but the temperature remains

constant! (This can be explained by

considering that it takes energy to break thebonds holding the material together.)

The amount of energy it takes to melt or boil a

certain amount of material is called a latentheat.

Latent Heat



For water, the latent heat of f usion (heat

needed to melt ice to water) is 79.7 cal/gm.

For water, the latent heat of vaporization (heat

needed to boil water) is 540 cal/gm.

For alcohol, the latent heat of vaporization is

less at 204 cal/gm.

Introduction superficial heat and cold therapy



� Physiological effects that produce pain relief direct result of the tempelevation on the tissue and cellular function.

� And through a reflex reaction

� Heat reduce pain & muscle spasm while decreasing joint stiffness and

contractures

� Produce hyperemia , speed metabolic process & hematoma resolution

� Heat is useful for bursitis and tensoynovitis along with superficial

thrombophlebitis

� Causes an introduction of reflex vasodilatation

Superficial heat



� While the physical properties differ, none of

these agents are able to overcome the

combination of skin tolerance , tissue thermal

conductivity , and the body s response toproduce localized temperature elevations of

more than a few degrees at depths of a few

centimeters

� Conduction ,conversion & convection

Heat indications



� Pain

� Muscle spasm

� Decreased joint stiffness and contractures

� Myofascial pain and fibromyalgia

� Production of hyperemia

� Acceleration of metabolic process

� Hematoma resolution

� Bursitis and tenosynovitis

� Superficial thrombophlebitis

� Induction of reflex vasodilatation

Heat contraindication



� Acute inflammation , abscess, trauma, edema orhemorrhage

� Bleeding disorders

�

Insensitivity� Inability to communicate or respond

� Poor thermal regulation

� Areas of malignancy

� Ischemia (inadequate blood supply)

� Atrophic skin & scar tissue

Superficial cold-cryotherapy



� Reduce blood flow

� Decreases metabolic activity

� Lessens muscle tone spasm

� Decreased swelling� Inhibits spasticity and clonus

� Increase gastrointestinal motility

� Slows nerve conduction� Produces analgesia

Cryotherapy



� Restricted to superficial agents that are

inexpensive , but effective including:

� -ice ,cold water, refrigerated units, vaporizing

liquids (vapo-Coolant spray ), and chemicalpacks

� Chilling cause an initial period of

vasoconstriction until subcutaneous tissuesreach 15 degree C

cryotherapy



� Thereafter , vasodilatation occur ,howevervessels are still constricted compared tonormal

�

Temp to 13- 15 degree C for 10 to 20 minutesare used

� Cold should be provide just long enough toprevent swelling and bleeding but prolonged

use should be avoided as cold can retardhealing

Cold indications



� Musculoskeletal trauma

� Edema / hemorrhage control & analgesia

� Pain

� Muscle spasm

� Spasticity

� Adjunct in muscle re-education

� Reduction in metabolic activity

Cold contractions



� Ischemia

� Cold intolerance /hypersensitivity

� Reynaud's

� Severe cold pressor responses

� Cold allergy

� Insensitivity

Cryotherapy cold therapy



� Cold modalities range in temp between 32 degree F65 F

� Heat is removed from the body & absorbed by the cold

modality

� Tissue temperature is LOWERED

� Cold therapy applied is thought to activate a mechanism usedto conserve heat in the bodys core

� This mechanism triggers a series of metabolic & vascular

events that produce the beneficial effects of cryothorepy .

� Can be used during all stages of healing

Pain control



� Cold therapy acts as a counterirritant

� Cold application affects pain perception &

transmission by:

� -interrupting pain transmission (stimulate-diameter A-beta n. fibers)

� Decreasing n . Conduction velocity

� Reducing m. spasm

� Reducing or limiting edema

Systemic effects of cold exposure



� If circulating blood temperature decrease to 0.2 degrees,thenthe hypothalamus(bodys thermoregulatory center) kicks in

� General vasoconstriction in response to cooling of the

posterior hypothalamus.

� Decreased respiratory and heart rates� - Heart rate decreases (wants to localize the cold area)

� Shivering &increased muscle tone

� -if the heart decrease too much where the core temperature.

reaches hypothermia

Application of Cryotherapy



� Ice massage: should not be applied during Acute inflammatory stage as itis not compatible with compression

� 5-15 min.-reduces pain ,desensitizes the trigger points

� Vigorous ice massage

� Ice pack : type of ice- cubed,flaked

�Commercial cold packs chemical reusable

_ Be aware of frostbite;use insulating layers between cryo-cuff/Polarcare:provide approx.40mm hg

Cold water immersion

- Ice bucket 40 degrees 50 degree F

- Whirlpool 50 degrees 60 degreesF

Vapour coolent spray: superficial rapid cooling through evoporation,vertticallyno temperature change below epidermis,will numb the area breifly(trigger points ).

T E N S



What is TENS?



� Transelectrical Neuro Stimulation

� The application of low voltage electrical pulses to

the nervous system through the skin via

electrodes



Mechanism of action



� Gate control theory: Conventional

� Natural opiates: Acupuncture like settings

� Primary indication: PAIN

� An Approach to pain control

± Trancutaneous Electrical Nerve Stimulation:

± Any stimulation in which a current is applied across



± Any stimulation in which a current is applied acrossthe skin to stimulate nerves

± 1965 Gate Control Theory created a greatpopularity of TENS

± TENS has 50-80% efficacy rate

± TENS stimulates afferent sensory fibers to elicit

production of neurohumneral substances such asendorphins, encephalin and serotonin (i.e. gatetheory)

CONTRAINDICATIONS



� 1st Trimester pregnancy

� Epilepsy avoid head and neck

� Eyes

� Open skin

� Over the chest if patient has any cardiac condition

� High BP� High fever

� Tuberculosis

� Numb skin

� Carotid sinus

Indications



± Control Chronic Pain

± Management post-surgical pain

± Reduction of post-traumatic & acute pain



Precautions



± Can mask underlying pain

± Burns or skin irritation

± prolonged use may result in muscle

spasm/soreness

± caffeine intake may reduce effectiveness

± Narcotics decrease effectiveness

Biophysical Effects



�

Primary use is to control pain through Gate ControlTheory

� May produce muscle contractions

� Various methods

± High TENS (Activate A-delta fibers) ± Low TENS (release of F-endorphins from pituitary)

± Brief-Intense TENS (noxious stimulation to active C

fibers)

Common Modes of TENS for

Nerve Stimulation



Nerve Stimulation

CONVENTIONAL Frequency 10-

100 Hz

Amplitude low

to medium

Place electrodes

at perimeter

Of pain, over

nerve Segment

Pt perceives a

distinct

parethesia on

painful region

or segment

STRONG low

rate

Frequency < 10

Hz Pulse

duration 100-

300usec

Over nerve

related to m in

or remote

Uncomfortable

rhythmic

muscle

contractions

MODES



Brief intense Freq. 60-150Hz.Pulse duration50-

250usec

Over nerve relatedto m in or remote

from pain

Uncomfortabletetanic

contractions that

fatigues, at patient

tolerance

Pulse Burst Modulated Freq.:

HIGH 60-100, Low

.5-4Hz 50-200usec

As above Weak to strong

intermittent

tetanic muscle

contract and

paresthesias

MODES



MODULATED Freq, Pulse

duration and

Amplitude Are

modulated

separate or

together

Any of previously

Mentioned sites

Weak to strong

sensation, with or

without muscle

contraction

Hyperstimulation Freq. 1-100

Pulse Duration Up

to 500 ms

Amplitude High

Accupuncture

points

Sharp burning

sensation at

tolerance. No

muscle contraction

Acceptable Electrode Placement



� D

irectly over pain� Superficial peripheral nerve

� Over dermatomes

� Acupressure point

� Over myotomes

� Motor points

� Placement can be unilateral, bilateral or crossed.



ULTRASOUND

A Deep Thermal & Non-thermal

Mechanical Modality

What is Ultrasound?



� May be used for diagnostic imaging,

therapeutic tissue healing, or tissue destruction

� Thermal & Non-thermal effects

� We use it for therapeutic effects

� Can deliver medicine to subcutaneous tissues

(phonophoresis)

Ultrasound



� Waveform

± Therapeutic ultrasound waves range from 750,000

to 3,000,000 Hz (0.75 to 3 MHz)

Transducer



�

A device that converts one form of energy to another� Piezoelectric crystal: a crystal that produces (+) and (-)

electrical charges when it contracts or expands

± Crystal of quartz, barium titanate, lead.

� Reverse (indirect) piezoelectric effect: occurs when analternating current is passed through a crystal resulting incontraction & expansion of the crystal

± US is produced through the reverse piezoelectric effect



Types of Current



� Direct Current: the uninterrupted unidirectional flow

of electrons

�

Alternating Current: the uninterrupted bidirectionalflow of electrons

± Ultrasound is produced by this type of current flowing

through a piezoelectric crystal

� Pulsed Current: the flow of electrons interrupted by

discrete periods of noncurrent flow

� Longitudinal waves travel in solids & liquids



�

Transverse waves cannot pass throughfluids; found in the body only when

ultrasound strikes bone

Frequency� Frequency: number of times an event occurs in

1 second expressed in Hertz or pulses per



1 second; expressed in Hertz or pulses per

second

± Hertz: cycles per second

± Megahertz: 1,000,000 cycles per second

�

In the U.S., we mainly use ultrasound frequencies of 1, 2and 3 MHz

� 1 = low frequency; 3 = high frequency

�

q frequency = o depth of penetration� o frequency = sound waves are absorbed in

more superficial tissues (3 MHz)



Coupling Agents



�

Optimal agent distilled H20(.2% reflection)

± Improperly coupled head causes o temp.

� Types of agents:

± Direct

± H20 immersion ± Bladder

Direct Coupling



� Effectiveness is q if body part is hair, irregularshaped, or unclean

� Must maintain firm, constant pressure

� Various gels utilized

Water Immersion



�

Used for odd shaped parts� Place head approx. 1 away from part

� Operators hand should not be immersed Nometal on part or operators hand

� Ceramic tub is recommended

� If nondistilled H20 is used, intensity can be o.5 w/cm2 because of air & minerals

� Dont touch skin except to briefly sweep skinwhen bubbles form

Bladder



� H20 filled balloon or plastic bag coated withcoupling gel

� Use on irregular shape part

� Place gel on skin, then place the bladder onthe part, and then place gel on bladder

Indications� Soft tissue healing & repair

J i t t t & ti



� Joint contractures & scar tissue

� Muscle spasm

� Neuroma

� Trigger areas

� Warts� Sympathetic nervous system disorders

� Postacute reduction of myositis ossificans

� Acute inflammatory conditions (pulsed)

� Has been shown to be ok to use following thestopping of bleeding with an acute injury (pulsed)



Contraindications� Acute conditions (continous output)

I h i i i d i l ti



� Ischemic areas or impaired circulation areas

� Tendency to hemorrhage

� Around eyes, heart, skull, or genitals

� Over pelvic or lumbar areas in pregnant or

menstruating females� Cancerous tumors

� Spinal cord or large nerve plexus in high doses

� Anesthetic areas

� Stress fracture sites or over fracture site beforehealing is complete (continuous); epiphysis

� Acute infection

Thermal Effects� o blood flow



� o sensory & motor nerve conduction velocity� o extensibility of structures (collagen);q joint

stiffness

� o collagen deposition

�Mild inflammatoryresponse

� q muscle spasm

� q pain

Nonthermal Effects



� o cell membrane permeability

� o vascular permeability

� o blood flow

� Synthesis of protein

� q edema� Diffusion of ions

� Tissue regeneration

� Formation of stronger CT

Pulsed Ultrasound

� Stimulates phagocytosis (assists q of chronic



inflammation)

Clinical Applications Soft Tissue & Plantar

Warts



� Pitting edema - o temp. makes thick edemaliquefy thus promoting lymphatic drainage

� o fibroblasts = stimulation of collagen

production = gives CT more strength

� Plantar Warts - 0.6 W/cm2 for 7-15 min.

Clinical Applications Scar Tissue, Joint

Contracture, & Pain Reduction



� o mobility of mature scar

� o tissue extensibility

� Softens scar tissue

� o pain threshold

� o n. conduction velocity



Clinical Applications

� Chronic Inflammation - Pulsed US has been



Chronic Inflammation Pulsed US has been

shown to be effective with q pain & o ROM

± 1.0 to 2.0 W/cm2 at 20% duty cycle

� Bone Healing Pulsed US has been shown to

accelerate fracture repair ± 0.5 W/cm2 at 20% duty cycle for 5 min., 4x/wk

Treatment Duration & Area

� Length of time depends on the

Size of area



± Size of area

± Output intensity

± Goals of treatment

± Frequency

� Area should be no larger than 2-3 times the surface areaof the sound head ERA

� If the area is large, it can divided into smaller treatmentzones

� When vigorous heating is desired, duration should be10-12 min. for 1 MHz & 3-4 min. for 3 MHz

� Generally a 10-14 day treatment period



Phonophoresis

� US is used to deliver a medication via a safe, painless,



, p ,

noninvasive technique

� Opens pathways to drive molecules into the tissues

� Not likely to damage or burn skin as with iontophoresis

�

Usually introduces ananti-inflammatory drug

Phonophoresis



�Factors affecting rate of medication diffusion ± Hydration higher water content = skin more penetrable

± Age better with younger ages

± Composition better near hair follicles, sebaceous glands &sweat ducts

± Thickness thinner skin is better� Types of medications

± Corticosteroids hydrocortisone, dexamethasone

± Anesthetics - lignocaine



Even they have

the right to stayhealthy.....

electrophysical agent 1

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