Trauma By Source Flashcards
What are the 6 types of trauma?
blunt force, sharp force, projectile, chemical, thermal, and blast
What are individual characteristics?
characteristics unique to a particular object/person (ex. DNA)
What are class characteristics?
characteristics unique to a wide group of things (ex. tire tread)
What does blunt force trauma result from?
force impacting a bone over a wide area, causing discontinuities and fracture lines
What are the three traits of BFT objects?
size, shape, and weight
In BFT, what sized widths need less force to cause fractures?
small widths
What are the key characteristics of shape traits in BFT?
cross-sectional shape (round vs. angular), longitudinal configuration (straight vs. curved), and patterned injuries
Is weight applicable in falls and auto accidents?
No
Bone bruise/occult intraosseous fracture
trabecular bone breaks causing blood to pool
Epiphyseal fracture
fusion has started but not finished –> weaker than normal –> breaks apart again
What are the two steps that occur when force impacts the skull?
- in-bending at site of impact with out-bending around impact site
- fracture lines form on out-bent surfaces and radiate out in all directions
When force impacts the skull, fracture lines start on the ____ surface and progress ____.
inner; outward
What is the diploe?
the inside table of the bone of the skull
Significance of areas of buttressing when force is applied?
areas of buttressing guides where blunt forces can be dissipated as fracture lines don’t go through these denser areas
What is the Lefort 1 fracture?
separates maxilla
What is the Lefort 2 fracture?
mid-face separates from the rest of the cranium
What is the Lefort 3 fracture?
entire face is separated from the braincase
Ring fracture
rare, caused by skull being forced down onto vertebral column or pulled away, encircles the base of the skull
What are the eight steps to BFT wound analysis?
- description of wounds
- estimation of size
- shape
- direction
- energy
- number (minimum)
- sequence of blows
- any miscellaneous estimations
What does sharp force trauma result from?
results from narrowly focused, dynamic compression forces applied to bone
What are the three types of sharp force trauma?
- Puncture (from a vertical direction)
- Incision (from force being applied across the bone surface)
- Cleft (vertical force from long sharp edge)
Hanging
body suspended, hyoid breaks 8% of the time
Ligature
cord, ect. applied force, hyoid breaks 11% of the time
Manual
squeezed by hands, hyoid breaks 34% of the time
Is blunt force trauma slow or high velocity?
slow velocity
Is ballistic trauma slow or high velocity?
high velocity
What is wounding power correlated to?
the kinetic energy dissipated during deceleration through the target
Greater loss of velocity =
greater damage
Faster bullet =
greater damage
Bigger bullet =
greater damage
What does severity of a gunshot wound depend on?
the amount of KE lost in the tissue
What is the mechanism of wounding for a GSW?
the temporary and permanent cavities inside the tissues
Penetrating GSW
enters but doesn’t exit the body
Perforating GSW
enters and exits the body
What type of GSW causes the most internal damage?
penetrating GSW
Temporary cavity
tunneling of bullet in tissue with tissue expansion on each side leading to massive tearing of immediate and remote tissues; there and gone faster than the eye can see
TRUE or FALSE: increased KE lost = decreased size of temporary cavity
FALSE
Permanent cavity
wound track with remains in tissues after temporary cavity has disappeared
What are the f factors affecting loss of KE?
amount of KE it started with, caliber/construction/configuration, angle of yaw, tumble, tissue characteristics
Is more energy dispersed in more dense or less dense tissues?
more dense tissues
What are the 5 components of bullet wound analysis?
- description of wounds
- direction of fire
- estimation of caliber
- number of wounds
- sequence of wounds
How can an entrance wound be identified?
creates cone-shaped defect (internal beveling)
How can an exit wound be identified?
reverse cone from entrance wound such that beveling is now on external surface
How is direction of force determiend?
determined from the spatial (straight-line) relationship of entrance and exit wounds
What are the three dimensions of direction of force?
- anterior to posterior
- right to left
- superior to inferior
What causes a keyhole defect?
when bullet enters, it enters at an angle such that it chips a thin piece of bone opposite to the side it enters
Why is caliber estimation so unreliable?
bone defects can be elastic, bullets may deform, thickness of bone can effect deformation, pre-existing fracture lines and sutures can cause entrance wounds to be smaller
Chemical trauma
death by slow poisoning such that it leaves traces in the bone (poison contains elements that bone mistakes for normal material)
What are the 4 changes fire can cause to bone?
fracturing, coloration, changes in chemical composition, and deterioration
What are the 5 elements of thermal trauma?
- white heat line
- heat border
- charring
- delamination
- curved transverse fracture
What does a curved trans verse fracture indicate?
direction of burning
