FARADIC CURRENTM. USMAN KHANSr. LecturerZCPT**M. USMAN KHAN

TRUE FARADIC CURRENTThe true faradic current is an unevenly alternating current, with one phase of high amplitude and short duration and the other phase of low intensity and longer duration.Faradic current has a pulse duration of 1ms with a frequency of 50 Hz.

**M. USMAN KHAN

M. USMAN KHAN

**M. USMAN KHANDURATIONAMPLITUDEAMPLITUDEINDURATION

M. USMAN KHAN

PRODUCTIONIt is usually obtained by using an induction coil, either using a cell battery or the AC mains. An EMF of 3 to 6 volts is used **M. USMAN KHAN

M. USMAN KHAN

FARADIC TYPE CURRENTSFaradic type current are interrupted currents with a pulse duration of 0.2 to 1msec. They are unidirectional pulses which may be depolarized or non-depolarized.**M. USMAN KHAN

M. USMAN KHAN

FARADIC TYPE CURRENTSAll faradic type of currents must be surged to produce a normal tetanic-like contraction and relaxation. **M. USMAN KHAN

M. USMAN KHAN

FARADIC TYPE CURRENTSIn surge current the intensity of successive pulses increases gradually, each impulse reaching a peak value greater than the preceding one then falls either suddenly or gradually.Surge can be adjusted from 2 to 5 seconds surge continuously, or by regularly selecting frequencies from 6 to 30 surges/minute **M. USMAN KHAN

M. USMAN KHAN

FARADIC TYPE CURRENTSRest period (pause duration) should be at least 2 to 3 times as long as that of pulse to give the muscle the sufficient time to recover( regain its normal state) The pulse duration can be regulated from 0.02, 0.05, 0.1 or 1.0 m sec. The most comfortable pulse is 0.1ms at 70 Hz.

**M. USMAN KHAN

M. USMAN KHAN

PHYSIOLOGICAL EFFECTSFaradic and faradic type of currents stimulate a nerve by bringing change in semi-permeability of cell membrane and by altering the resting potential of the membrane. When the cell membrane potential reduces to the critical level, the muscle supplied by the nerve is activated to contract. **M. USMAN KHAN

M. USMAN KHAN

PHYSIOLOGICAL EFFECTSTo produce a tetanic contraction by faradic type of current, stimuli must be applied at a rate of at least 30 stimuli per second. The strength of muscle contraction will depend on the number of motor units brought about into action.**M. USMAN KHAN

M. USMAN KHAN

PHYSIOLOGICAL EFFECTS1. ON SENSORY NERVESFaradic and Faradic type of currents causes a pricking sensation. With higher intensities it becomes painful. In sensitive patients it may cause intense irritation or even a rash.**M. USMAN KHAN

M. USMAN KHAN

PHYSIOLOGICAL EFFECTS2. ON MOTOR NERVES AND MUSCLESTrue faradic current stimulates the motor nerve and brings about a tetanic-like muscle contraction in the muscle fibers innervated by the nerve i.e stimulated. The faradic type of current has to be surged to produce a tetanic- like muscle contraction. The contraction of muscle brought about by the faradic and faradic type of current resemble a voluntary muscle contraction. **M. USMAN KHAN

M. USMAN KHAN

The contraction is tetanic in type because the stimulus is repeated 50 times or more / sec; 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.**M. USMAN KHAN

M. USMAN KHAN

PHYSIOLOGICAL EFFECTS3. ON DENERVATED MUSCLESThe faradic and faradic type of current will not stimulate a denervated muscle because the duration of the stimulus is too short for the muscles to appreciate. **M. USMAN KHAN

M. USMAN KHAN

PHYSIOLOGICAL EFFECTS4. ON PARTIALLY DENERVATED MUSCLESFaradic and faradic type of current will produce muscle contraction in a partially denervated muscle but will require a higher intensity than required to stimulate a normal muscle, because only the innervated fibers will cause muscle contraction. The strength of current needed to produce a muscle contraction will depend on the degree or extent of denervation.**M. USMAN KHAN

M. USMAN KHAN

PHYSIOLOGICAL EFFECTS5. ON CIRCULATION:The normal muscle when contract and relax under the influence of surged faradic current cause a pumping action on blood vessels and thus improve venous return which in turn increases the blood flow to the area.**M. USMAN KHAN

M. USMAN KHAN

THERAPEUTIC USES1. MUSCLE EXERCISEFaradic type and true faradic currents stimulation can be used to exercise an innervated muscle where :a) Active movement is not possible such as when the part is in plaster following a fracture, in order to maintain muscle strength during the period of immobilization. **M. USMAN KHAN

M. USMAN KHAN

THERAPEUTIC USESb) Active movements are not allowed such as in cases of tendon, ligament or meniscal repair. 2. REEDUCATION OF MOVEMENTIn cases of tendon transplants, faradic and faradic type of currents are helpful in teaching patients the new muscle action. **M. USMAN KHAN

M. USMAN KHAN

THERAPEUTIC USES3. DIAGNOSTIC TOOLInnervated muscles will contract in response to faradic and faradic type of current at minimal intensity.Partially innervated muscle will require more intensity of current than normal.Completely denervated muscle will not respond even at higher intensity.**M. USMAN KHAN

M. USMAN KHAN

THERAPEUTIC USES4. OEDEMA REDUCTIONFaradic and faradic type of current can be used to reduce edema using a special technique called Faradism under-pressure.**M. USMAN KHAN

M. USMAN KHAN

THERAPEUTIC USES5. STRETCHING SHORTENED TENDONUsing faradic and faradic type of currents, Tightened structures such as tendons can be loosened. For this purpose the technique used is called Faradism under tension.6. FARADIC BATHSSimilar to direct currents, faradic and faradic type of currents can be applied using a mono-polar or bi-polar baths.**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONThe general principals of application of faradic and faradic type of current are similar to any low frequency current application.

**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONTHE PATIENTPosition should be carefully and appropriately selected.Patient should be explained in simple words about the treatment procedure and what to feel.Strictly warn the patient to not to touch any part of the apparatus or manipulate any of the controls. To report to you if any unwanted sensations are felt.Expose only the area to be treated, rest of body parts should be suitably coved.Inspect the skin condition, cover any streaks or scratches with petroleum jelly or tape.**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONTest the skin sensation for Pin-Prick.Wash the area to be treated with soap and water, then dry, and then soak the area with warm saline for 5 minutes. Place the electrodes appropriately over the areas to be treated and secure them in place by a crepe bandage, masking tape or a rubber bandage.Check that no metal is touching the patients skin.**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONTHE APPARATUSSelect the apparatus that provides faradic or faradic type of current.Check the apparatus to see that :a) No current is leaking onto the casing.b) The terminals are marked (active & indifferent)c) The intensity control is working, providing a smooth output.d) All controls are at zero.**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONConnect wires and electrodes tightly.Select appropriate size and type of active and indifferent electrodes.Connect apparatus to mains.

**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONTREATMENTInform patient that you are going to commence the treatment .Before switching on the mains and the apparatus check to see that all controls are at zero.Turn the main switch and control switch on.Increase the intensity very slowly till you get the desired strength of muscle contraction.Note the sensation reported by the patient.

**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONSet the duration (time) of treatment.Remain within the calling distance from the patient, a call bell can be given to patient.At the end of the treatment time, turn the intensity control slowly to zero then switch the apparatus and the mains off.Remove terminals from the apparatus.Undo bandages to remove electrodes.Inspect the skin and make a note of any reaction.

**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONAFTER CAREClean and dry patient skin.Allow patient to dress up.Help patient from the plinth.Escort patient to any other area if he/she needs other treatments.

**M. USMAN KHAN

M. USMAN KHAN

GENERAL PRINCIPALS OF APPLICATIONRECORDING OF TREATMENTArea treatedElectrode placement areasSize of active electrodeThe indifferent electrode usedThe strength of muscle contractions obtained.Duration of treatment.Instruction to patient

**M. USMAN KHAN

M. USMAN KHAN

*Surging means gradual increase and decrease of peak intensity