Therapeutic Ultrasound is modality used in physiotherapy

1. THERAPEUTIC ULTRASOUND
Dr. Dheeraj Lamba
Associate Professor/ Head Department of
Physiotherapy

2. At the end of this lesson the student will be able to:
• State the definition of Ultrasound.
• Describe the Parameters of Ultrasound.
• Demonstrate the methods of application of ultrasound.
• Determine the dosage of ultrasound.
• Demonstrate an understanding about the Uses,
Physiological and therapeutic effects.
• Identify the contraindications and dangers.
• Demonstrate the method of Phonophoresis.
OBJECTIVES:

3. DEFINITION:
• A form of acoustic vibrations occurring at a frequency
that is too high to be perceived by the human ear.
• The therapeutic frequency is in the range of 0.5 to 5
MHz.
• Commonly used frequency in physiotherapy is 1MHz
and 3MHz.

4. PIEZOELECTRIC EFFECT :
• It is the ability of certain materials to generate an electric
charge in response to applied mechanical stress.
• Reverse piezoelectric effect –electrical energy is used to
produce mechanical stress and deformation

6. PARAMETERS
• Intensity / output.
• Duration
• Mark- Space ratio.

7. TYPES OF ULTRASOUND WAVES
• Continuous Wave - no interruption of beam: best for maximum
buildup, sometimes heat.
• Pulsed Wave - intermittent “on-off” beam modulation. It ensures that
the energy available in each pulse (pulsed averaged intensity) is
high enough for mechanical rather than thermal effects.
• It is represented as
• The mark : space ratio
It is the ratio of the pulse length to the interval.

9. Ultrasound Machine & Coupling Agent
Dispensers

10. METHODS OF APPLICATION
• Direct method / contact cream method.
• Bath method or immersion technique.
• Bag method.

11. Direct method
• Gel or Creams should be
applied over the
treatment part
• Only use approved
coupling agents.
• Remove air bubbles by
passing sound head over
area (before power is
increased)
© 2005 – FA Davis

12. Immersion Technique
• Used to treat irregularly
shaped areas.
• The limb is immersed in a
tub of degassed water.
• Transducer is held appx. 1”
from the body part.
• Avoid the formation of air
bubbles.
© 2005 – FA Davis

13. Pad (Bladder) Method
• A mass of conductive gel
– Commercial pads
– Self-made bladders
• Conforms to the
treatment area.
• Commercial pads help
limit the size of the
treatment area.
© 2005 – FA Davis

14. DOSAGE
MODES:
Continuous – to heat tissue/scar breakdown.
Pulsed (50%, 20%) – to heal tissue.
FREQUENCY:
1 MHz – US energy will penetrate to a depth of 2.5 to 5
cm. Given for deep lesions.
3 MHz – US energy will penetrate to a depth of 1.5 cm.
Given for superficial lesions.

15. INTENSITY:
 To heal: 0.05 – 0.8 W/cm2
 To heat:
0.8 w/cm2 – 1.0 w/cm2 for superficial tissues.
Greater than 1.5 w/cm2 for deeper tissues

16. MECHANICAL EFFECTS
• Cavitation's.
• Acoustic streaming.
• Standing waves.
• Micro massage.

17. Cavitations:
Formation of gas bubbles that expand & compress due to
pressure changes in tissue fluids.
• Stable cavitation
Occurs when the bubbles oscillate to and fro within the
ultrasound pressure waves but remain intact.
• Transient (or collapse) cavitation
Occurs when the volume of the bubble changes rapidly
and then collapses
Causes high pressure and temperature changes .
Results in gross damage to tissues.

18. Acoustic Streaming
• Unidirectional flow currents in a fluid due to the presence
of sound waves.
• Exerts viscous stress on the cell membrane and
increase membrane permeability.
Standing waves
• Formed due to reflected waves being superimposed on
the incident waves.
• Possibility of marked local heating where the amplitude
of the combined waves is high.

19. Micromassage
The micromassage effect of ultrasound occurs at a
cellular level where the cells are alternately compressed
and then pulled further apart.
The waves of compression and rarefaction may produce
a form of micromassage, which could reduce oedema.

21. PHYSIOLOGICAL EFFECTS
• Increased peripheral arterial blood flow.
• Increased tissue metabolism.
• Increased permeability of membrane.
• Increased pain threshold.
• Relief of muscle spasm.

22. THERAPEUTIC EFFECTS
• Pain relief.
• Resolution of inflammation.
• Effect on healing.

23. Physiological and therapeutic effects

24. INDICATIONS
• Bursitis.
• Tendonitis.
• Pressure sores.
• TMJ syndrome.
• Sports injuries.
• Capsulitis.
• Contractures
• Plantar fascitis.
• Calcaneal spur.
• Tennis / Golfer's elbow.
• Coccydynia.
• OA / RA.
• Scars.
.

25. CONTRAINDICATIONS
• Rapid dividing tissues -Neoplasm's
• Pregnant Uterus.
• Epiphyseal Plates
• Infections.
• Vascular Problems
Hemorrhage.
Hematoma.
Haemarthrosis.
Thrombosis.
Thrombophlebitis.
Ischemia.

26. • Radiotherapy.
• Metal / plastic / acrylic implant.
• Pace maker.
• Avoid specialized tissues – eyes, ears, ovaries and
testes.
• Central nervous system tissue.
• Anesthetic areas.

27. DANGERS
• Burns could occur if the heat generated exceeded the
physiological ability to dissipate it.
• Tissue destruction would result from transient cavitation.
• Blood cell stasis and endothelial damage may occur if
there is standing wave formation.
These dangers are more likely with high-intensity
continuous output with a stationary head or over bony
prominences.

28. PRECAUTIONS
• Check thermal sensation.
• Use the right dosage.
• Move the transducer.
• Avoid bony prominences.
• Avoid excess heat sensation.
• Don’t keep the ultrasound head in air when the machine
is ON.
• Maintain good contact between ultrasound head and
tissues.
• Test the equipment.

29. PHONOPHORESIS
It is the movement of drugs through skin into the
subcutaneous tissues under the influence of ultrasound.
• Ultrasound facilitates the passage of some drugs into
and through the skin.
• The effects are due both to absorption of the drug and to
the ultrasound.
• Lower ultrasonic frequencies lead to deeper drug
penetration.
• Pulsing ultrasound lead to better drug penetration.