Imaging the Skeleton Flashcards
why are radiological images taken
Images taken for assessment of:
- Trauma,
- Degenerative diseases
- Metabolic diseases
- Infections
- Neo-plasms
what do lucent lesions of the bone look like
dark areas (leucent region means that it looked darker) – this suggests that the bone is thinner at that point
what do Sclerotic lesions of the bones look like
- these are whiter areas
– this suggests that there is more density and more bone tissue therefore it stops more of the x rays getting through
what is a periosteal reaction
– loss of smooth appearance of the edges of bones
– have the bone precursor cells in the periosteum therefore you loose the smooth appearances of the edges of the bone
what do soft tissue calcifications look like
– white patches in the soft tissue
– this is an indication that you have abnormal bone formation or an abnormal calcification in a tendon or a ligament that you shouldn’t have
what is osteopenia
– localised reduction in bone density
– this is a bigger area, of reduction in bone density
– precurosor to osteoporosis
what is osteonecrosis
- death of bone with loss of shape of the bones
what are fractures and what do they look like in the x ray
– discontinuity of bone,
- black lines separating pieces of the bone, bits of bone that is broken off that you can see
what is orthapaedic hardware
- metal and plastic
what is joint integrity
- loss of joint space and loss of joint orientation
what is the difference in what you can view in internal rotation and in external rotation in the humerus
- In external rotation the rotator cuff muscles pull the greater tubersotiy and cause the humerus to rotate laterally so you see more of the lesser tubersosity
- In internal roation subscapularis is acting see less of the lesser tuberosity
why do some bones show gaps between them that can look like fractures
- epiphyseal plate this is when the cartilage is not calcified and the bone is still growing, this can be seen in children
what are you considering when looking at abnormal x rays
- Shape, size and or orientation of the bones and joint surfaces
- Breaks in the bone
- Extra bone (calcification)
- Loss of bone
- Foreign objects
what is the problem with x rays
- bone in front can obscure bone behind and therefore you are not able to view the bone behind unless you view it from a different angle therefore different views of x rays need to be used
what are the limitations of x rays
- only calcified tissue shows up clearly
- soft tissue does not show up
- not sensitive for example you loose 30% of bone mass before it shows up on the x ray
- bone in front can obscure the internal bone processes or structures behind
- processes taking place inside the bone cannot be seen - avascular necrosis and osteomyelitis
what can iodine be used for
Inject iodine or air into the joint as this changes the density of the shoft tissues therefore you can see the shoulder joint and see how big the joint capsule is and how it drapes into the axillar
what is dexa scan used to do
- checks bone density
- can also be used for body fat
how does a dexa scan work
Uses 2 different low energy x-ray sources.
why is it a good thing to use 2 different low energy x ray sources
Using 2 different x-ray sources improves accuracy
