MSK Imaging Flashcards
What color is air, soft tissue, fluid, bone and metal on X ray?
Black Dark grey Grey Light grey White
What is fluoroscopy and what type of procedures do we use it for?
Continuous real time X-ray, like an X-ray movie.
Injections, biopsies, angiograms and GI evaluations
What is a CT?
2 strengths of CT?
3 weaknesses?
X-ray on steroids
Good for bony lesions and fast
Radiation, expensive, and poor soft tissue
4 features of t1 and t2 weighted images on MRI?
T1: how quickly can it become magnetized, fat is bright, water is dark, good for detecting anatomy
T2: how quickly it loses its magnetization, fat is dark, water is bright, good for detecting pathology
3 strengths and 4 weaknesses of MRI?
Soft tissue, no radiation, entire cross section on image
Takes a long time, subject to motion artifact, inferior to CT for hemorrhage and bony lesions, and expensive
Big strength of US and what two pathologies can we see with it?
Tears and muscle disruptions with or without hematoma
When performing DEXA, what is the T score and Z score used for?
T score: used in the diagnosis of osteoporosis
Z score: used to compare BMD to others
What 4 views to order on X-ray for shoulder? 4 for knee? 3 for ankle? 5 for wrist? 4 for elbow?
AP, true AP, scapular Y and axillary AP, lat, oblique, merchant AP, lat, mortise AP, lat, oblique, carpal tunnel, and scaphoid AP, lat, oblique, radial head/Greenspan
3 general guidelines when looking at an x ray for a fracture?
Follow the Cortex and look for disruptions
Check the joint for narrowing and widening
Check joint above and below injury location
What is the difference between a complete and incomplete fracture?
Complete is where all parts of the cortex are disrupted and incomplete is just come cortex (example is a green stick fracture)
What do we mean when we say articular extension in regards to a fracture?
Has the fracture line extended into the articular surfaces and if so, is the joint displacement in any way
What do we mean by displacement, angulation, and rotation in regards to a fracture and how do we name them?
Displacement is from the axial line, how far are the prices displaced and we name it for the distal part relative to the proximal part.
Angulation is same thing, but now they are lined up at an angle instead of their normal axial axis
Rotation is the fractured pieces have rotated in relation to each other, probably a spiral fracture. Again name it for the distal piece relative to the proximal.
What is a green stick fracture?
Mid diaphyseal fractures in the forearm and lower legs in kids.
A force is applied to the bone causing it to bend until its integrity fails and the convex side breaks and the concave side stays intact
Explain the salter Harris classification of fracture?
There are 5 types of fracture of salter and they are named in relation to the growth plate:
1: Straight across through the growth plate
2. Above: through the growth plate and at some point passes through the metaphysis
3. Lower: passes through the growth plate and then down through the epiphysis
4. Through: passes through the metaphysis, growth plate, and epiphysis
5. RAM: growth plate is not displaced, it is crushed by compression
Osteoblasts produce what 3 things and osteoclasts produce which 1 thing?
Type 1 collagen, rank ligand and osteopontin
MMPs
