FARADIC CURRENT.pptx

Knowledge about the faradic current and its physiological effects,indications and its contraindication and the methods of the application of the faradic current,motor point stimulation and its benefit used in physiotherapy

1. FARADIC CURRENT Presented by: Priyanka Bhusal

2. INTRODUCTION: A faradic type current is a short duration interrupted direct current with a pulse duration of 0.1-1 ms and frequency of 50-100 Hz.

3. WAVEFORMS OF FARADIC CURRENT: Waveform- Biphasic, asymmetrical, unbalanced, spiked Positive portion – Short duration, high amplitude and spiked Negative portion – Long duration, low amplitude and curved

4. MODIFIED FARADIC CURRENTS  Faradic currents are always surged for treatment purposes to produce a near normal tetanic -like contraction and relaxation of muscle. Current surging means the gradual increase and decrease of the peak intensity.

5. PHYSIOLOGICAL EFFECTS OF FARADIC CURRENT: STIMULATION OF SENSORY NERVES: When a faradic current is applied to the body, a mild prickling sensation is experienced. The sensory stimulation causes a reflex vasodilation of the superficial blood vessels and is confined to the superficial tissues.

6. STIMULATION OF MOTOR NERVES:  It occurs if the current is of a sufficient intensity, causing contraction of the muscles supplied by the nerve distal to the point of stimulus. A suitable faradic current applied to the muscle elicits a contraction of the muscle itself and may also spread to the neighboring muscles. The character of the response varies with the nature and strength of the stimulus employed and the normal or pathological state of muscle and nerve. The contraction is tetanic in type because the stimulus is repeated 50 times or more / sec.

7. If this type is maintained for more than a short time, muscle fatigue occurs. So, the current is commonly surged to allow for muscle relaxation i.e. “when the current is surged, the contraction gradually increases and decreases in strength in a manner similar to voluntary contraction”. Stimulation of the nerve is due to producing a change in the semi-permeability of the cell membrane: This is achieved by altering the resting membrane potential. When it reaches a critical excitatory level, the muscle supplied by this nerve is activated to contract.

8. Reduction of swelling and pain: It occurs due to alteration of the permeability of the cell membrane, leading to acceleration of fluid movement in the swollen tissue and arterial dilatation. Moreover, it leads to increase metabolism and get red of waste products.

9. CHEMICAL EFFECTS: The ions move one way during one phase of the current and in the reverse direction during the other phase of the current if it is alternating. If the two phases are equal, the chemicals formed during one phase are neutralized during the next phase. In faradic current, chemical formation should not be great enough to give rise to a serious danger of burns because of the short duration of impulses.

10. INDICATIONS : FACILITATION OF MUSCLE CONTRACTION: When a patient is unable to produce a muscle contraction,electrical stimulation may be of use in assisting voluntary contraction.  MUSCLE REEDUCATION: Muscle contraction is needed to restore the sense of movement in cases of prolonged disuse or incorrect use; and in muscle transplantation. The brain appreciates movement not muscle actions, so the current should be applied to cause the movement that the patient is unable to perform voluntarily.

11. MAINTAINING ROM: Electrical stimulation of faradic current helps to stretch the shortened tissue and increases ROM. LOOSENING AND PREVENTION OF ADHESION: Adhesion is formed where there is no muscle contraction. Electrical stimulation by faradic current causes muscle contraction which loosen and stretches the adhesion.

12. IMPROVEMENT IN VENOUS AND LYMPHATIC DRAINAGE NEUROPRAXIA OF MOTOR NERVE FOR REPLACING ORTHOSIS: low stimulation frequency used to enhance the function of a paralyzed muscles thus eliminating the need for a splint or brace or orthosis .

13. CONTRAINDICATIONS: Skin lesions: The current collects at that point causing pain. Certain dermatological conditions: Such as psoriasis, tinea and eczema. Acute infections and inflammations. Thrombosis. Loss of sensation. Cancer. Cardiac pacemakers. Superficial metals.

14. FARADISM FOR STIMULATION OF DENERVATED MUSCLE: Equipments Required: Low frequency electronic stimulator 2 leads [1cathode & 1anode] 2 suitably sized carbon/metal electrode Aqueous gel, a sand bag • Bandage, straps, micropore or adhesive tape 2 small basin of warm water Towels , soap Insulating cream [petroleum jelly, vaseline ]

15. PROCEDURE FOR STIMULATION:  Position the patient comfortably in a relaxed position Support the muscle to be stimulated in pain- free position with area to be treated adequately exposed In case of supine lying knees should be flexed by keeping the pillows or towels under the knee Examine the area to be treated; note any cuts, skin lesions and inflammations. Check that there is no contraindication to treatment like sensation

16. PROCEDURE FOR STIMULATION: Equipment should be tested prior to treatment by placing the electrodes over the palm & increasing intensity to check whether equipment is working properly. Explain the procedure properly to patient that there will be pricking sensation on area to be treated & there is no need to panic & if intensity will be high he/she must tell. Clean the electrodes with soap water to avoid any chemical on electrode & also clean the area to be treated to remove any grease on skin which helps in better penetration by reducing the skin impedence .

17. PROCEDURE FOR STIMULATION: Place the active electrode on muscle & inactive electrode on nerve trunk if for group action. If it is for stimulating individual muscle we will use pen electrode. Connect the electrodes properly to skin with the help of tape/strap. Explain the patient that during the procedure he/ she should not move the limb suddenly or do not touch the equipment.

18. TECHNIQUE OF APPLICATION: Motor point stimulation Group muscle stimulation

19. GROUP MUSCLE STIMULATION: Stimulation which makes all the muscles of a group work together Satisfactory method of re-educating the action of muscles which normally work as a group, such as quadriceps, the small muscles of the foot, and muscles of pelvic floor

20. MOTOR POINTS STIMULATION: This method has an advantage that each muscle performs its own individual action & that the optimum contraction of each can be obtained  Selected when training a new muscle action or when isolation of one muscle is indicated; e.g. vastus medialis may be stimulated to overcome a quadriceps lag, or abductor hallucis for muscle weakness.