Forensic Aspects of Trauma 1 Flashcards
Define injury
Physical harm or damage to someone’s body by accident or as an attack
Damage to any part of the body due to application of mechanical force
Kinetic force = ?
What is the clinical application of this?
1/2mass x velocity^2
Means 1kg brick held against scalp causes no damage, but the same brick thrown at the scalp will smash the skull
Apart from velocity of force what is the other most important factor in determining the injury caused?
Area over which the force acts
Smaller area = more concentration of force = more damage
Excessive mechanical force can cause what 4 things?
Compression (squashing)
Torsion (twisting)
Traction (pulling apart)
Tangenital (shearing)
What are the classifications of injury?
Appearance or method of causation
Manner of causation
Nature of injury
What are the different appearances or methods of causations?
Abrasion, contusion, laceration, stab wound, incised wound, gunshot, burns
What are the different manners of causation?
Suicidal, homicidal, accidental, self-inflicted
What are the different natures of injury?
Blunt force, sharp force, explosive
What are the different blunt force injuries?
Contusions
Abrasions
Lacerations
What are contusions?
Blue/purple areas that result from burst BVs in the skin
They turn yellow with time due to metabolism of the blood - this can help you age them
What are examples of patterned contusions?
Finger tip bruising, tyre tracks, shoe marks
What are abrasions?
Scratches/grazes - scrapping of the skin surface
How can you tell the direct of insult in an abrasion?
Skin tag indicates direction
What might be examples of patterned abrasions?
Serrated knife drawn across skin, bite marks
What are lacerations?
Tearing/splitting os kin due to crushing force
Raised edges may be seen with surrounding bruising
What are the two types of laceration?
Full thickness (affecting underlying fat and muscle) and partial thickness (affecting dermis)
What are the factors affecting prominence of contusions?
Skin pigmentation
Depth ad location - occurs more easily over loose skin (scrotum, eyebrow)
Fat –> inc sc fat –> more bruising
Age - children’s skin looser and more delicate, elderly BV less supported
Resilient areas incl. buttock and abdo
Coagulative disorders
Give examples of coagulative disorders that would make someone more prone to bruising
Thrombocytopenia, (alcoholic) liver disease, haemophilia, Von Willebrand’s disease, bone marrow disease
What are sharp force injuries?
Those caused by any weapon with a sharp cutting edge
What are the two types of sharp force injuries?
Incised wounds
Stab wounds
What are incised wounds?
Caused by slashing motion
Wound longer than it is deep
Generally caused by knife/broken glass
What are stab wounds?
Deeper than they are long
Caused by thrusting motion (generally knife)
What are examples of patterned stab wounds?
Screwdrivers, scissors etc.
