Electrical stimulation is a technique that utilizes an electric current to activate the nerves driving muscles and extremities. Electrical stimulation causes a single muscle or group of muscles to contract. Direct current is an electric current whose direction is always fixed with time. This electric current from the electrical stimulation machine moves from the pole which is always the same, from the positive pole to the negative pole.
a. Constant direct current (CDC) (galvanic).
This current is called Galvanic current.
The intensity of the galvanic current can be adjusted, as needed, and it must be very low
b. Uninterrupted direct current (IDC).
c. Alternating Current (AC).
Alternating current is an electric current whose direction is always changing periodically with time. Alternating current is divided into 3 parts:
a. Faradic and sinusoidal currents
b. Interference current
Faradic & Sinusoidal Currents
– Faradic currents.
– Alternating electric current (AC) is not symmetrical.
Short duration: 0.01 ms.
Frequency: 50-100 Hz.
– Sinusoidal currents.
– Symmetrical alternating electric current.
Duration: 10 ms.
Frequency: 50 Hz.
– A Combination of two alternating currents, different medium frequencies, and mutual interference.
– A new frequency arises.
– Frequency Modulation Amplitude = Difference between the two frequencies.
– Deeper penetration.
USAGE OF GALVANIC & FARADIC FLOWS IN MEDICAL
Also called ion transfer. Treatment is by transferring ions into the mucous membrane, through the epidermis. The principle works that the ions with the same charge will repel each other. The purpose of using iontophoresis is to treat local pain, reduce edema, reduce inflammation, and it’s also to kill bacteria.
Skin disorders/diseases, including idiopathic hyperhidrosis, minor injuries, fungal infections.
Contraindications: Patients with a history of allergies, areas whose skin; peeling, healing (new scar tissue), Impaired skin sensation.
HVPGS (High Voltage Pulsed Galvanic Stimulation).
It’s a substitute/modification of pure galvanic (CDC) but it’s rarely used anymore.
Specialty: Gel form. monophase with twin peaks, Duration fixed, in microseconds up to 200 ms, “High” voltage > 100 V.”
HVPGS Clinical Application
Wound healing, Reduction of edema, Pain relief of nerve and muscle stimulation, Stimulation of the circulatory system (through the activation of muscle pumps and sympathetic nerve stimulation).
Contraindications to the HVPGS Application
Circulatory disorders, direct stimulation of the caroticus sinus, stimulation of the heart (especially patients with pacemakers), pregnancy, and epilepsy.
Physiological Effects of Electrical Stimulation
a. Peripheral / peripheral nerve excitation
b. Changes in permeability of non-excitatory tissue cell membranes.
c. Modified formation of osteoblasts and osteoclasts.
d. Skeletal muscle contraction and its effect on muscle strength, speed of contraction, and resistance to fatigue.
e. The contraction of smooth muscles and relaxation that affects the flow in the arteries and veins.
f. Muscle contraction and its effect on joint movement and synergistic muscle activity.
Galvanic Flow Physiological Effects.
1. It modulates your refract pain with other sensory perceptions and stimulation of endogenous morphine.
2. Vasodilation of blood vessels.
3. Spur muscle contraction.
– Electric current stimulates motor stimulation through increased nerve excitability.
Muscle contractions are beneficial for pumping muscles to increase circulation by increasing back blood flow.
Galvanic Current Therapeutic Effects.
1. Maintaining muscle physiology in the form of muscle contractions.
2. Smooth superficial blood circulation.
The physiological effects of Faradic Currents.
1. Sensory nerve stimulation.
2. Motor nerve stimulation.
3. Contraction effect.
4. Effects on innervated muscles.
5. Chemical effects.
Faradic Current Therapeutic Effects.
1. Facilitate muscle contractions.
2. Re-contracting the function of muscle work.
3. Exercising new muscle functions.
4. Train the paralytic muscle.
5. Prevent and release tissue adhesions.