US

Question 1

what is acoustic impedence

Answer 1

a material’s ability to transmit sound related to density

Question 2

what happens when sound waves are absorbed?

Answer 2

sound is transmitted to thermal energy

Question 3

what happens when sound is refracted?

Answer 3

the wave is bent in a different direction

Question 4

what happens when sound is reflected?

Answer 4

they interact with other waves to enhance or diminish intensity

Question 5

in order of high attenuation to least, where do you put bone, muscle, tendons, and skin?

Answer 5

bone > tendon > skin > muscle

Question 6

what frequencies are most often on US machines?

Answer 6

1 and 3 MHz

Question 7

what does wave frequency determine?

Answer 7

treatment depth

Question 8

how do you determine intensity of US?

Answer 8

no consensus on intensity, you want the pt to feel the heat

Question 9

what is the main difference between continuous and pulsed US?

Answer 9

pulsed is nonthermal

Question 10

what is the BNR?

Answer 10

the crystal is imperfect and can thus create areas of high intensity

Question 11

what is the clinical relevance of BNR?

Answer 11

can cause hotspots

Question 12

treatment area should be how many times the size of the ERA?

Answer 12

2x

Question 13

how much does a tissue have to heat up to cause extensibility?

Answer 13

inc 7degF or 4degC

Question 14

which frequency of US targets deeper tissue?

Answer 14

1Hz up to 6cm

3Hz up to 2.5cm

Question 15

which frequency heats up tissue faster?

Answer 15

3Hz

Question 16

describe tissue cooling after tx

Answer 16

tissue, regardless of type, takes 5 minutes to cool

Question 17

why do applicator heads need to be kept 90 deg?

Answer 17

reduces reflection

Question 18

what has high transmission rate for US?

Answer 18

water and US gel

Question 19

what has okay/bad transmission rate for US?

Answer 19

creams and ointments

Question 20

what has poor transmission rate for US?

Answer 20

air

Question 21

is there evidence for US for trigger point pain?

Answer 21

yes, but adding it to manual shows no additional benefit

Question 22

is there evidence for US for cervical pain?

Answer 22

no

Question 23

is there evidence for US for subacromial shoulder pain?

Answer 23

evidence against use

Question 24

is there evidence for US for frozen shoulder?

Answer 24

no

Question 25

there is evidence for US for inflammation in which two locations? (4)

Answer 25

tennis elbow, acute carpal tunnel, calcific tendinitis, and arthritis

Question 26

is there evidence for US for tissue healing?

Answer 26

no

Question 27

is there evidence for US for tissue extensibility?

Answer 27

no

Question 28

what are the 13 contraindications for US?

Answer 28

1. eyes
2. impaired congnition
3. impared sensation
4. pacemaker
5. cancer
6. TB
7. hemorrhage
8. impaired circulation
9. anterior neck
10. skin disease
11. area of radiation
12. bone growth at epiphysis
13. pregnancy

Question 29

what are the 2 precautions for US?

Answer 29

1. plastic or cemented implants

2. SC or superficial regenerating nerves

Question 30

when would you use low intensity pulse US?

Answer 30

bone healing, not good evidence