Bone Imaging Part 1 Flashcards
Almost all radiographic evaluation of bone begins with ___views exposed at ___ degrees of each other. This is called __________
2 views
90 degrees
Orthogonal
What are some downfalls of plain films for bone imaging?
They cannot view the entire circumference of tubular bone and are not good for evaluating soft tissue injuries
MRI is excellent for evaluating components of the ______________ and _____________musculoskeletal structures
Medullary canal
non-osseous
What is used to categorize bone marrow disorders? What are the categories?
MRI
Reconversion (reversal of normal conversion), marrow replacement (by metastatic cells), myeloid depletion (loss of red marrow due to chemo/rads), myelofibrosis (replacement of marrow by fibrous tissue due to chemo/rads)
___________ is frequently used as contrast medium for CT and MRI
Gadolinium
T1 weighted images emphasize _____
Fat
T2 weighted images emphasize _____
Water
CT is subject to scatter with __________ objectects
Imbedded metallic objects
CT uses ______________ to created images. One head CT = 8 months of _______________
ionizing radiation
Background radiation
What is the most common type of low energy fracture in elderly patients? What type has the highest mortality?
Distal radius is most common (FOOSH)
Femoral neck has highest mortality
What causes poor bone stock?
Osteoporosis, cancer (femoral neck is MC), bone cyst, bed ridden/wheelchair bound, metabolic disease
What is a Toddler’s fracture and how does this happen?
Stable spiral fracture of the mid shaft of the tibia. This is a twisting injury as a result of getting their leg caught on a slide or running.
What are causes of fractures in non-ambulatory children?
Osteogenesis imperfecta, abuse, tumor
High energy fractures usually occur in what population?
Usually young males
What are common causes of high energy fractures?
Occupational, sports, MVC, fall from height, doing something stupid…
What is the second most common cause of death in the younger population after MVC?
Fall from height
What can happen if you have soft tissue involvement with a high energy fracture?
Vascular compromise and compartment syndrome (both surgical emergencies)
T or F: multiple bones or significant comminution is not typically seen with high energy fractures
False. this is common
_____________ are described as a disruption in the continuity of all or part of the cortex of a bone
Acute fractures
Fracture where the bone is broken through and through
Complete fracture
Fracture where only part of the cortex is fractured? Examples of this type of fracture?
Incomplete fracture
Green stick and torus
What are some radiographic features of acute fractures?
Fracture lines are more lucent
Abrupt discontinuity of the cortex
Edges of the fracture are ragged and rough
Where do sesamoid fractures almost always present?
In the thumb, posterolateral knee, and great toe
What are accessory ossicles and where are these commonly found?
Accessory epiphyseal or apophyseal ossification centers that do not fuse with the parent bone
Mc found in the foot
What is the difference between dislocation and subluxation and where do they occur?
Dislocation is complete loss of contact between the bones in a joint and subluxation is when the bones in a joint are in partial contact with each other.
They both only occur at joints.
How do you describe the number of fragments in a fracture?
Simple (two fragments) vs comminuted (multiple fragments)
How can you describe the direction of the fracture line
Transverse (<30° angulation), oblique (>30° angulation), spiral
How can you describe the relationship of the fragments?
Displacement, angulation, shortening, rotation
How do you describe the communication of fractures to the outside?
Open vs closed fracture
Fracture description mnemonic
OLD ACIDS
O- open or closed
L- location
D- degree
A- articular involvement
C- communited/type
I- intrinsic bone quality
D- displacement, angulation, rotation
S- soft tissue injury
If a fracture produces two fragments it is called a __________ fracture. If the fracture produces more than two fragments it’s called a ____________
Simple
Comminuted
What is it called when a portion of the shaft exists as an isolated fragment?
Segmental
What is it called when a fracture produces a central fragment that has a triangular shape
Butterfly fragment
Fracture line is perpendicular to the long axis of the bone
Transverse fracture
Fracture line is diagonal in orientation relative to the long axis of the bone
Diagonal or oblique
Fracture of a twisting force or torque
Spiral
abnormalities of the position of bone fragments secondary to fractures describe the relationship of the ____________ fragment relative to the _____________ fragment
Distal fracture
Proximal
Amount by which the distal fragment is offset. Described in either terms of percent or fractions
Displacement
Angle between the distal and proximal fragments
Angulation
How much overlap there is of the ends of the fragments
Shortening
Unusual abnormality affecting long bones. Can relate to one join in comparison to another as well.
Rotation
T or F: closed fractures have NO communication with the outside, and open fractures ARE exposed to the outside atmosphere
True
What kind of fracture is common in younger patients, occurs at anatomically predictable places, and causes the bone fragment to pull from the parent bone by contraction of a tendon or ligament
Avulsion fractures