This document discusses ultrasound and electrotherapy. It describes how ultrasound uses mechanical vibration to generate heat in tissues. Different coupling methods like gels or immersion can be used depending on the treatment area. Electrotherapy can stimulate muscles or nerves to help with conditions like pain, edema, or muscle atrophy. Electrical currents are used to induce muscle contraction or stimulate sensory nerves according to the gate control or descending pain theories of treatment. Placement of electrodes can target specific tissues or structures.

1. Maham Yousuf
Assignment: ELECTROTHERAPY
Submitted to: Sir Jam Feroze

2. Ultrasound

3. Introduction
 Ultrasound (US) is a form of MECHANICAL energy, not electrical energy and therefore
strictly speaking, not really electrotherapy at all but does fall into the Electro Physical Agents
grouping. Mechanical vibration at increasing frequencies is known as sound energy. The
normal human sound range is from 16Hz to something approaching 15-20,000 Hz (in
children and young adults). Beyond this upper limit, the mechanical vibration is known as
ULTRASOUND. The frequencies used in therapy are typically between 1.0 and 3.0 MHz
(1MHz = 1 million cycles per second).

4. Treatment Area
 US heats a limited area
 About the size of a catsup
packet
 Treatment area should be 2 to
3 times the size of the ERA
 For larger areas, divide the
treatment area into smaller
zones

5. Coupling Methods
Application
DIRECT COUPLING
IMMERSION METHOD
PAD/BLADDER METHOD

6. Coupling Methods
 Ultrasonic energy cannot pass through the air
 A coupling medium is required
 Medium should be water-based
 Coupling method should confirm to the body area
 The body area should be clean and relatively hair-free

7. Direct Coupling
 Gel or Creams
 Only use approved coupling
agents
 Apply liberally to area
 Remove air bubbles by passing
sound head over area (before
power is increased)

8. Direct Coupling
 Move the sound head s-l-o-w-
l-y
 4 cm/sec
 Moving the head faster
decreases heating
 If the patient describes
discomfort, decrease the
output intensity

9. Coupling Ability of Various Media
Substance Transmission
 Saran Wrap 98
 Lidex ge, fluocinonide (.05%) 97
 Thera-Gesic 97
 Mineral oil 97
 US Transmission gel 96
 US Transmission lotion 90
 Chempad-L 68
 Hydrocortisone powder (1%) 29
 Hydrocortisone powder (10%) 7
 Eucerin cream 0
 Myoflex 0
 White petrolatum gel 0

10. Immersion Technique
 Used to treat irregularly
shaped areas
 The limb is immersed in a
tub of degassed water
 If tap water is used,
increase the output
intensity by 0.5 w/cm2
 Transducer is held appx.
1” from the body part
 Avoid the formation of air
bubbles

11. 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

12. Electrode Placement
•Electrodes may be placed:
–On or around the painful area
–Over specific dermatomes, myotomes, or
sclerotomes that correspond to the painful area
–Close to spinal cord segment that innervates an
area that is painful
–Over sites where peripheral nerves that
innervate the painful area becomes superficial
and can be easily stimulated
–Over superficial vascular structures
–Over trigger point locations

13. –Over acupuncture points
–In a crisscrossed pattern around
the point to be stimulated so the
area to be treated is central to
the location of the electrodes
–Bipolar application resulting in
similar physiologic effects
beneath each electrode
–Monopolar setup  both an
active and dispersive pad set up
causing higher current density at
the active electrode
–Quadripolar technique

14. Physiologic Response To
Electrical Current
•Electricity can have an effect on each
cell and tissue it passes through
–Type and extent is dependent on the type of
tissue, its response characteristics, and the
nature of current applied
•Reactions can be:
–Thermal
–Chemical
–Physiologic

15. •Can be used to:
–Creating muscle contraction through
nerve or muscle stimulation
–Stimulating sensory nerves to help in
treating pain
–Creating an electrical field in biologic
tissues to stimulate or alter the healing
process
–Creating an electrical field on the skin
surface to drive ions beneficial to the
healing process into or through the skin

16. Therapeutic Uses of
Electrically Induced Muscle
Contraction – High-volt
Currents
•Muscle re-education
•Muscle pump contractions
•Retardation of atrophy
•Muscle strengthening
•Increasing range of motion
•Reducing Edema

17. Muscle Re-Education
•Muscular inhibition after surgery or injury is
primary indication
•A muscle contraction usually can be forced
by electrically stimulating the muscle
•Provides artificial use of inactive synapses
•Restore normal balance to system as
ascending sensory info is reintegrated into
movement patterns
•Patient feels the muscle contract, sees the
muscle contract, and can attempt to
duplicate this muscular response

18. Muscle Pump Contractions
•Used to duplicate the regular muscle
contractions that help stimulate
circulation by pumping fluid and blood
through venous and lymphatic
channels back to the heart
•Can help in reestablishing proper
circulatory pattern while keeping
injured part protected
•Sensory level stimulation has been
shown to decrease edema in sprain

19. Retardation of Atrophy
•Electrical stimulation reproduces
physical and chemical events
associated with normal voluntary
muscle contraction and helps to
maintain normal muscle function
•No specific protocol exists 
clinician should try to duplicate
muscle contraction associated with
normal exercise routine

20. Increasing Range of
Motion
•Electrically stimulating a muscle
contraction pulls joint through
limited range
•Continued contraction of muscle
group over extended time appears
to make contracted joint and
muscle tissue modify and lengthen

21. The Effect of Non-contractile
Stimulation on Edema
•Sensory level direct current used as a driving
force to make charged plasma protein ions in
interstitial spaces move in the direction of
oppositely charged electrode
•Cook et al. hypothesized that
1) the electrical field facilitated movement
of charged proteins into lymphatic channels
2) Electrical field caused indirect stimulation
of autonomic nervous system, stimulating
release of adrenergic substances, increasing
smooth muscle activity and lymph

22. Therapeutic Uses of
Electrical Stimulation of
Sensory Nerves –
Asymmetric Biphasic
Currents (TENS)
•Gate Control Theory
•Descending Pain Control
•Opiate Pain Control

23. THANKS