1. Define Diathermy
    Diathermy converts high- frequency electromagnetic energy (radio waves) into therapeutic heat within the body tissues
  2. Two Types of diathermy
    • Shortwave Diathermy
    • Microwave Diathermy (not used in US)
  3. Physiological Response to Diathermy
    • Tissue Temp rise
    • Altered cell membrane function
    • Increased nerve conduction velocity
    • Increased Pain threshold
    • Increased muscle elasticity
    • Increased blood flow
    • Increased tissue metabolic rate
    • Muscle relaxation
    • Enhanced recovery from injury
  4. Nonthermal Effects of Diathermy
    • Occurs at Cellular Level
    • Repolarize damaged cells correcting dysfunction
    • Reactivates the sodium pump allowing the cell to regain normal ionic balance
  5. Three Frequencies by FCC
    27.12, 13.56, 40.68
  6. Two Types of Diathermy
    • Induction field (magnetic)
    • Capactive field
  7. Capacitor Electrodes
    • Air space plate (spaced enevly from tissue)
    • Pad electrodes ( not commonly used)
  8. How do capacitor electrodes work?
    • the patient is placed between two electrodes or plates and becomes part of the circuit
    • Tissue tat offers the greatest resistance to current flow tend to develop the most heat
    • Tissue high in fat contect resist current
    • Can overheat
    • 2.5-5 cm but uneven becuase of changes in resistance or tissue
  9. How does Induction electrodes work?
    • Inductance technique uses induction electrodes and creates a stronger MAGNETIC field than electrical field
    • Pt not part of the circuit
    • Not tissue specific
    • Greatest heat generated in muscular layer
    • Safer
  10. Types of Induction Electrodes
    • Cable/Coil (comles set up not used often)
    • Drum (most common)
  11. Cable/ Coil Electrodes
    • Induction - magnetic
    • need toweling between cable or coil and Pt
    • Wrap coil round part to be treated
    • Created EDDY currents in tissues which creates oscillations of ions and increases tissue temp
  12. Drum electrodes
    • Cable coiled within drum
    • Magnetic field is up to 5 cm away from the drum -may need a towel between skin and drum, amount of heat depends on the distance between drum and skin
  13. Pulsed Diathermy
    • The off time is generally a lot longer thant he on time (allows heat to dissipate)
    • Can be used from theram effects - use higher intensities and longer treatment times to achieve thermal effects
  14. Advantages of Diathermy
    The primary advantage of using shortwave diathermy as opposed to radiant or conductive heating methods is the possibility of reaching deeper tissues
  15. Disadvantages of Diathermy
    • With some methods the treatment area is not visible
    • The sourse of heat is constant and doesn't cool down during treatment increasing the risk for burns
    • Equipment is cost and time consuming to set up
  16. Clinical Applications of Diathermy
    • Post acute musculoskeletal injuries
    • Decreased cirulation
    • Decreased metabolism
    • Decreased Collagen Extensibility
    • Joint Stiffness
    • Pain
    • Joint contractures
    • Tissue Healing
    • Muscle tension
    • Muscle Guarding
  17. Dosage of Diathermy
    • Intensity - heat should be gentle many not feel heat with pulsed
    • Duration 15-30 mins effects last 30mins
    • Frequency - daily or twice a day for sub acute condition and less frequently for chronic condictions
  18. Be Able to Compare Diathermy to Ultrasound
    look in notes
Card Set
Mod Test One