mahoney 6

Question 1

describe projection, position, view

Answer 1

• PROJECTION = the direction in which the beam travels through the body to arrive at the cassette
  
  • generally never use the term view in your interpretation (view is opposite of projection)
• Any other IMAGE besides an AP or lateral is called a POSITION
  
  • position refers to the PART THAT IS CLOSEST TO THE CASSETTE
    
    • medial oblique of the foot/ankle: medial surface is closest to the cassette when following the course of the x-ray beam

Question 2

how to look at quality of the X-ray

Answer 2

• Are any parts inadvertently “cut-off”?
• more importantly refers to the appearance of the bones
  
  • if the bones look TOO WHITE –> underexposed
  • If the bones look TOO DARK –> overexposed
• Can you see the soft tissue outline, including skin?

Question 3

Congruous joint

Answer 3

normal alignment

Question 4

deviated joint

Answer 4

articular surfaces intersect outside of the joint

Question 5

subluxed joint

Answer 5

articular surfaces intersect inside of the joint

Question 6

dislocated joint

Answer 6

articular surfaces not in contact

Question 7

Closed fracture

Answer 7

skin intact (difficult to determine from x-ray alone)

Question 8

open fracture

Answer 8

skin break due to bone pushing out of skin

Question 9

complete fracture

Answer 9

fracture involves both cortices

Question 10

intra-articular

Answer 10

fracture into the joint

Question 11

Transverse fracture

Answer 11

fracture is roughly perpendicular to long axis of bone

Question 12

oblique

Answer 12

fracture length is

Question 13

Spiral fracture

Answer 13

fracture length is > 2x the diameter of the bone at the level of the fracture

Question 14

comminuted fracture

Answer 14

more than 2 pieces to fracture

Question 15

avulsion fracture

Answer 15

piece of bone pulled away from main body of bone

Question 16

impacted/compression fracture

Answer 16

bones are driven into each other (which generally results in increased bone density at the point of impaction

Question 17

stress fracture

Answer 17

not able to be seen initially on x-ray and implies a small, non-displaced fracture

usually seen in three weeks as it starts to form an external callus from periosteal reaction

Question 18

greenstick fracture

Answer 18

• bending force on a long bone causes one cortex to break, but the opposite cortex remains in place-usually seen in children
  
  • the broken branch snaps on one side, while the inner side is bent and still in continuity

Question 19

displaced fracture

Answer 19

the direction of displacement is described by the distal fragment

• there is a medial and proximal displacement of the fracture with no more than 1mm of displacement

Question 20

what are the important characteristics of describing fractures

Answer 20

• attitude (sticking up or down)
• location
• complete/incomplete
• displaced/non-displaced
  
  • if displaced, in WHAT DIRECTION and extent of displacement in mm