Imaging

Question 1

Why do we use imaging in musculoskeletal conditions?

Answer 1

to make an accurate tissue diagnosis
rule out red flags
determine prognosis or track a disease
indications for surgical intervention

Question 2

What populations would we avoid imaging?

Answer 2

acute ankle trauma, non-specific low back pain, traumatic cervical spine

Question 3

What are the 5 principles for using imaging MS conditions?

Answer 3

1. understanding of imaging results
2. only order imaging that will influence management
3. explain the imaging to the patient
4. provide relevant clinical findings on the referral form
5. work with radiographers & radiologists

Question 4

What are some advantages and disadvantages of x-ray

Answer 4

widely available, quick, cheaper

use of ionising radiation, cannot differentiate soft tissue, 2D image

Question 5

What are contraindications to x-ray?

Answer 5

pregnant or breastfeeding

Question 6

What does an xray allow you to see in OA pateints?

Answer 6

joint space narrowing, osteophytes, changes in shape of bone

Question 7

Describe the grading of OA as seen on xrays

Answer 7

0= no OA
1= doubftul OA (possible osteophytic lipping)
2= mild OA (osteophytes, possible JSN)
3= moderate OA (osteophytes, JSN, sclerosis, possible bony deformity)
4= severe OA (osteophytes, JSN, sclerosis, bony deformity)

Question 8

What are some advantages and disadvantages of CT

Answer 8

relatively cheap, fast & widely available
defines bone in detail & detects calcification
higher resolution than xray
3D images

uses ionising radiation
often requires injectable contrast
lower soft tissue contrast (than MRI)

Question 9

What are contraindications to CT

Answer 9

pregnancy, breastfeeding & children

Question 10

When would we use CT

Answer 10

complex fractures, small/hidden fractures deep within joints

Question 11

What are some advantages and disadvantages of bone scans?

Answer 11

can be combined with CT
may detect earlier stages of bony injury

high radiation dose
low resolution images
scan takes a long time to do
expensive

Question 12

What are contraindications to bone scans?

Answer 12

pregnancy, breastfeeding

Question 13

What are some advantages and disadvantages of ultrasound?

Answer 13

cheap, fast, widely available, portable 
dynamic imaging
can use interactively with patients 
able to image soft tissue in high resolution 
no radiation 

small field of view
unable to view bone & air
image quality depends on skill of operator

Question 14

Are there any contraindications to ultrasound?

Answer 14

nope

Question 15

What are some advantages and disadvantages to MRI?

Answer 15

all tissues can be imaged
no radiation
excellent soft tissue contrast
3D image

bone resolution not as clear as CT
expensive & slow
low availability
only non-weight bearing images

Question 16

What colour will fat, muscle & tendons/cartilage be on an MRI?

Answer 16

fat= bright white
muscle= grey ish 
tendons/cartilage= dark

Question 17

A T-1 MRI scan is good for what type of tissue?

Answer 17

meniscus/connective tissue, less so soft tissue/muscle

Question 18

A T-2 scan is good for what kind of tissue?

Answer 18

soft tissues especially tendons

Question 19

A STIR MRI scan is good for what conditions?

Answer 19

highlighting excess water which may occur during bone stress, bone marrow oedema, joint fluid & soft tissue pathology

Question 20

What are contraindications to MRI?

Answer 20

claustrophobia

any implanted metal