Electrotherapy lecture 01( basic concept) Continue..

Electrotherapy lecture (basic concept, electric current & Shock

Types of electricity / Current

Currents can be classified into

                         1 . Alternating (AC)

                         2 . Direct (DC)

                         3 . Pulsatile (PC)

TYPES EXPLAINED

1. Direct current (DC)

The current flows only in one direction.

 

2. Alternating (AC)

The continuous flow of

       electrons is bidirectional

 

Electrons flowing in an

alternating current always

move from the negative

       to positive pole

3.Pulsatile (PC)

Contains three or more pulses grouped together and may be undirectional or bidirectional

 

 

CURRENT FLOW THROUGH BIOLOGIC TISSUES

 

Electrical current tends to choose the path that offers the least(LESS) resistance to flow.

 

The conductivity of the different types of tissue in the body is variable. Typically, tissue that is highest in water content(highest in ion content) is the best conductor of electricity.

 

The skin has different layers that vary in water content, butgenerally the skin offers the primary resistance to current flow and is considered an insulator.

CURRENT FLOW THROUGH BIOLOGIC TISSUES

Blood is a biologic tissue that is composed largely of water and ions and is consequently the BEST electrical conductor of all tissues.

 

Muscle is composed of about 75 percent water. Muscle tends to propagate an electrical impulse much more effectively. So it is agood conductor.

 

Peripheral nerve conductivity is approximately six times that of muscle.

 

Fat contains only about 14 percent water and is thought to be apoor conductor.

 

Bone is extremely dense, contains only about 5 percent water, and is considered to be the poorest biologic conductor of electrical current.

Therapeutic uses of modalities

Promoting blood circulation

Stimulating the muscle activity

Influencing the nerves and transmission of pain

Warming the skin and tissues lying deeper

Stimulation of the metabolism processes and reinforcing the body’s defence mechanism

 

2.Sensory stimulation

To reduce pain

Used as placebo effect

3.Ion movement

4.Analgesia

5.Recent researches shows

Fracture healing

Wound healing

Ligament and tendon healing

 

Treatment of electric shock

Burn

It caused by:

Contact of the metal to the skin

Over dosage

Skin lesion

Metal in the part.

 

Concentration of current

It is caused by:

The presence of un-dissolved salt in solution

Creases on the pad

Pads unevenly moist

Any raised skin edges