SHORT WAVE DIATHERMY (SWD)

Short Wave Diathermy (SWD) is a treatment that uses electromagnetic energy to produce deep heating in joints and soft tissues. This form of heat can be applied to deeper structures than other forms of heat treatment.

1. SHORTWAVE DIATHERMY Dr Ranjan Mishra (PT) AIIMS ,Patna

2. Diathermy Diathermy is the application of Shortwave or microwave electromagnetic energy to produce heat and other physiological changes within the tissue The term ‘diathermy’ means ‘through heating’ or producing deep heating directly in the tissues of the body. ‘ Dia ’ through ‘ thermy ’ heat or temperature

3. PRINCIPLE OF DIATHERMY Before injury, the dipole molecules of the body tissue are arranged on the basis of polarity . When the tissue is damaged the dipoles distribution become irregular and deviates from polarity based arrangement . Under the influence of an electric field , they rotate according to the polarity of their charge in the direction of the field lines and get rearranged and tends to acquire its previous stage of polarity

4. CHALLENGES OF DIATHERMY As the subcutaneous layer is fatty , direct delivery of heat to the deep layers of tissue is not possible. Diathermy involves uneven and uncontrolled delivery of heat therefore sometimes instead of the target tissue , surrounding tissue gets affected .

5. Diathermy uses high frequency electric current to produce heat deep inside a targeted tissue. It can reach areas as deep as two inches from the skin’s surface. The diathermy machine does not apply heat directly to the body. Instead, the current from the machine allows the body to generate heat from within the targeted tissue. As the heat increases, it promotes blood flow. It can also help improve flexibility in stiff joints and connective tissue.

6. Effects of high frequency currents on the tissue. Vibrations of ion Dipole rotation Molecular distortation

7. PHYSIOLOGICAL EFFECTS Increased metabolism: Increased blood supply: General rise of temperature: Fall in blood pressure: Increased activity of sweat glands:

8. Therapeutic effect 1.Increase blood flow. 2. Help resolution of inflammation. 3. accelerate wound healing. 4. ↗ extensibility of deep collagen tissues. 5. ↘ joint stiffness. 6. Relief deep mus. Pain & spasm. ( via muscle spindle & Golgi tendon organ stimulation)

9. BENEFITS OF DIATHERMY Intense heat delivered provides pain relief and better flexibility Reduces inflammation Improves circulation Accelerate healing

10. TYPES OF DIATHERMY SHORT WAVE DIATHERMY LONGWAVE DIATHERMY MICROWAVE DIATHERMY ULTRASOUND DIATHERMY LASER DIATHERMY

11. SHORT WAVE DIATHERMY Def.: SWD is a modality that produces deep heating via conversion of electromagnetic energy to thermal energy. The pattern of heat produced depend on: Freq. used. type of SWD unit. water content of the tissues.

12. Shortwave diathermy current freq. 10 – 100 MHz (The shortest radiofrequency wave is used in therapeutic diathermy.) the commonly used in medical work having freq. of 27.12 MHz with wavelength of 11 meters

13. Modalities: Continuous and Pulsed (PSWD). PSWD: application of series of short pulses of SWD so that short periods of SWD interrupted by gaps where there is no SWD. The patient receives lower dose of SWD energy compared with continuous SWD applied of the same time and the tissues will receive lower thermal load.

14. Acute condition should be treated with low dose PSWD and chronic conditions should be treated with high dose SWD. PSWD is usually applied for 30 to 60 minutes once or twice a day,5 to 7 times in a week. SWD: produce both deep and superficial tissue heating, under certain controlled conditions. Thermal level diathermy is generally applied for 20 minutes.

15. Methods Of Applying SWD Inductive method Capacitive method

16. Inductive method Uses a long flexible, metal conductor, a thick wire covered in a thick rubber insulator. Also uses monode , diplode , or drum depending on size, shapes and numbers of coil and manufacturer. In both the cases a coil is used to produce high frequency alternating magnetic field. AC Current flowing within the coil produces a magnetic field perpendicular to coil. Magnetic field produces eddy currents in the tissues. This induced eddy current cause charged particles in the tissue to oscillate and that produce heat in the tissue.

17. Heating with inductive coil diathermy applicator is known as heating by magnetic field method because the electric current that generates the heat is induced in the tissues by magnetic field.

18. Capacitive Field Diathermy Uses capacitive plate diathermy applicators,which is made of metal encased in plastic housing or transmissive carbon rubber electrodes that are placed between felt pads. A high frequency AC current flow from one plate to other through the patient, producing an electric field and a flow of current in body tissue that is between the plates. Also referred to as “ condenser field diathermy ”

19. TYPES OF ELECTRODES Flexible pads: consist of metal electrode encased in rubber and produce an electrostatic field.

20. Space plates: consist of a rigid metal electrode encased in a Perspex cover produce electrostatic field.

21. Coil or cable electrode consists of a wire with plugs at either end creates electromagnetic field. Application using a coil electrode: 1. The coil wound evenly firmly 2.Pancake application

22. The monode : flat, rigid coil encased in plastic cover produce Electromagnetic field.

23. Diplode and drum electrode Consists of a flat coil electrode encased in Perspex cover with two wings produce electromagnetic field. Application using diplode : Adjust wings of diplode parallel to the skin of the treated area, electromagnetic field will produce.

24. FACTORS INFLUENCE FIELD DISTRIBUTION IN S.W.D( capacitor field method) Spacing : allows the lines of force in the electrostatic field to diverge before entering the tissues. This prevents concentration of heat in the superficial tissues and ensures more heating through the part. Spacing provided by: 1. wrapping flexible pads in towel. 2. flat felt spacing pads between pad electrode and skin 3. air when using space plates.

25. Normal spacing  even field distribution. Increased spacing  deep field concentration. Decreased spacing superficial concentration If the spacing is less than 25 mm more concentration in the treat superficial tissue. If spacing Increases more depth achieved. The distance between adjacent ends must be greater than the sum of skin electrode distance (A+B) otherwise the line of force will pass directly between Electrodes rather than tissues.

26. Electrode size: Guid lines for electrode selection & placement: 1. Electrode should be of equal size 2. Electrode should be slightly larger than the body part 3. Electrode should be equidistant & at right angles to the skin surface.

27. if the electrodes are too small than the diameter of treated part line of force will be concentrated superficially. If the electrodes are markedly larger the line of force will be lost in the air. Ideally, the electrodes should be slightly larger than the area treated.

28. To concentrate heat on one aspect of the part the electrode should be unequal in size. (smaller one placed over the area where concentration of heat is required). Or you can produce concentration of heat by using equal size electrodes but with unequal spacing (25 mm over concentrated area and more than 30 mm on other electrode).

29. Distance from short wave machine- To restrict exposure it is recommended that operator should remain 1 m from continuous wave diathermy equipment,0.5 m from pulsed treatment with capacitive electrode and 0.2 m from pulsed inductive applicators.

30. Electrodes arrangements Coplanar application both electrodes are placed on the same side of the limb.

31. Contra planar (transverse) applications an electrode is placed on either side of the limb.

32. Longitudinal application: one electrode is placed at each end of the limb.

33. Cross-fire application: For the treatment of sinuses, space plates positioned after half diagonally,of treatment time the positions are alternate. this ensures that the all the sinses membranes are heated. Care must be taken to avoid direct placement over the eye ,uterine disorders such as dysmenrrohea .

34. USES Musculoskeletal Disorders  Degenerative Joint Disorders Ex . OA and RA  Sprain  Strain  Hematoma  Muscle & tendon Tears  Capsule Lesions

35. DANGERS Burns Concentration of electric field • Impaired blood flow • Excess current • Hypersensitive skin • Leads touching skin Scalds Electric shock Overdose Precipitation of gangrene Faintness Giddiness

36. Contraindications Metal implants or metal jewelry (be aware of body piercings) Cardiac pacemakers Ischemic areas Peripheral vascular disease Perspiration and moist dressings: The water collects and concentrates the heat. • Tendency to hemorrhage, including menstruation. • Pregnancy • Fever

37. Sensory loss Cancer Deep X ray Tumours Unreliable patients Areas of particular sensitivity: Epiphyseal plates in children – The genitals – Sites of infection – The abdomen with an implanted intrauterine device (IUD) – The eyes and face – Application through the skull

38. Treatment with Shot Wave Diathermy on chronic low back pain Protocol SWD was applied by Condenser technique. Condenser pads were applied to the back with spacing between skin and electrodes provided by 1 to 2 inch layers of terry cloth. It was applied for 15 minutes three times in a week for six weeks. conclusions concluded that treatment with SWD may be benefited if SWD is used as an adjunct to NSAID.

39. The interventions done included HVLAT and SWD on 15 subjects in each group the subject received max of 9 treatment sessions, 3 times per week for 3weeks for both the groups. The outcome measures were VAS, ODI and ROM (flexion, extension). The objective of the study was to see the effect of HVLAT and SWD on outcome measures and compare them and Ergonomic advice being common to both groups. Concluded that high velocity low amplitude thrust manipulation can be used in rehabilitation of chronic mechanical low back pain patients. Comparison of Efficacy of SWD and High Velocity Low Amplitude Thrust Manipulation (HVLATM for management of chronic mechanical low back pain

40. Effects Of 10 Minutes Short Wave Diathermy (SWD) On Osteoarthritis (OA) Knee; Compared To 20 Minutes Short Wave Diathermy (SWD) General Objective: To compare the effects of 10 minutes (experimental) over 20 minutes (control) SWD in treatment of OA knee by using WOMAC. From analysis and examination the significant improvement was found in the group of patients who received 20 minutes SWD plus NSAIDs.So , it is almost clear that , 20 minutes SWD is more effective then 10 minutes of SWD.

41. Thank you…………..