Injury To The Body Flashcards
Excessive mechanical force can cause:
Compression
Traction (stretching)
Torsion (twisting)
Tangential (shearing)
Classification of injury
By appearance
Manner of causation
Nature of injury
What is a contusion?
A bruise - burst blood vessel in skin
Blunt force injuries
Contusions
Abrasions(graze/scratch)
Lacerations (cut/tear of skin)
What are tramlines bruise?
A cyclindrical instrument
Looks like train-tracks
Finger-tip bruising
Buckle bruise
Tyre bruise
What happens in people with liver disease?
Bruises are worse -fall over more and bruises show up worse.
What is an abrasion?
Scraping of very top layer
Bread-knife mark
Bite marks
Lacerations
Not usual patterned
Blunt force injury
‘Stringy bridges’
Sharp force injuries
Injury caused by sharp cutting edged implement
Incised wounds - more superficial, longer on surface than deep (slash)
Stab wounds - deeper penetrating, deeper than wider on surface
What is a vital reaction?
Inflammatory- bleeding bruising etc
Early post-mortem changes?
Temp degradation
Hypostasis
Rigor mortis
Last post-morgen changes
Decomposition and autolysis
Mummification
Adipocere
Skeletonisation
Hypostasis
When circulation ceases
RBCs seen through skin, gives colour - pink/purple
Oedema and skin blisters
Dully established by 6-12 hours
What is rigor mortis?
Stiffening and shortening of muscle fibres leading to rigidity of musculature and fixation of joints.
Due to reduction of ATP within muscles
‘Stuck’ in contraction
Factors affecting timing of rigor mortis:
Temperature Physical activity before death - more - rigor quicker Body temp at time of death Convulsions Electrocution
Decomposition 2 classes?
Putrefaction = microbiological degeneration
Autolysis = endogenous proteolytic degeneration
Putrefaction
Fern-like pattern of venous staining
After time, less well-defined.
Skin slippage
Gas produced by bacteria - very swollen
Mummification
Body ‘dries out’
Children prone to mummification
Adipocere
Waxy material on skins surface which hardens when dries out
Tends to occur in wet/ damp environments
Skeletonisation
All soft tissue completely degrades, left just with bones.
Estimating time since death
0-12 hours = body temp most useful - 1C drop per hour
24 hrs = rigor mortis and hypostasis
48hrs-3weeks = putrefaction
Months to years = adipocere, mummification, skeletonisation
