Ultrasound

Question 1

Why use ultrasound?

Answer 1

Kinetic energy from the sound waves is converted to heat via friction

Heat-
Decrease muscle spasm, joint stiffness, oedema/swelling & pain
Increase tissue extensibility

Question 2

What types of physiological effects does ultrasound have?

Answer 2

Thermal & Non-thermal

Question 3

What are the thermal effects of ultrasound?

Answer 3

Decreased pain perception
Decreased fluid viscosity
Increased tissue extensibility
Increased metabolic rate
Increased blood flow- assists in reducing swellin

Question 4

What are the non-thermal effects of ultrasound?

Answer 4

Acoustic streaming
Cavitation (Bubble formation)
Micro streaming

Question 5

The non-thermal effects of ultrasound are: Acoustic streaming, Cavitation (Bubble formation) & Micro streaming. What do these effects cause?

Answer 5

Membrane distortion/ permeability
Improve transfer of nutrients and metabolites
Facilitate the inflammatory and proliferation phases of healing

Question 6

What structures does ultrasound effect?

Answer 6

Deep or superficial soft tissue

Question 7

How do you apply ultrasound?

Answer 7

1) introduce
2) explain treatment & give informed consent
3) Ask about injury: how long/previous occurrence/current pain levels & contraindications
4) work out parameters: time= 1 min per size of treatment head, 1:4 ratio = 5 mins, Freq= 3(superficial) & 1(deep), pulse= 1:1 more energy, 1:4 less energy, Output= 0.4 acute, 0.6/0.65 sub-acute, 1 chronic
5) apply gel to head / area
6) test machine
7) place on area, keep moving in large or small circles
8) stop, clean head & area
9) explain they may feel buzzing/tingling up to 24hr after
10) Adverse effects?

Question 8

How do you decide how long to deliver ultrasound?

Answer 8

time= 1 min per size of treatment head, 1:4 ratio = 5 mins

Question 9

How do you decide pulse frequency?

Answer 9

Freq= 3(superficial) & 1(deep)

Question 10

How do you decide pulse duration (on:off)

Answer 10

pulse= 1:1 more energy, 1:4 less energy

Question 11

How do you decide output?

Answer 11

Output= 0.4 acute, 1 chronic

Question 12

What are the contraindications?

Answer 12

Acute Sepsis
Tumours
Deep X-ray therapy
Local infections
Vascular insufficiency
Active TB
Metal implants
Pacemakers
Central nervous tissue
Uncontrolled bleeding or anti-coagulant therapy
Over the eyes, reproductive organs or a pregnant uterus

Do you have any heart or circulatory conditions?
Are you feeling well in yourself?
Are there any infections in the area?

Question 13

What are some precautions to be considered?

Answer 13

Acute inflammation
Epiphyseal growth plates
Decreased sensation