Forensic Aspects of Trauma 1

Question 1

What is an injury?

Answer 1

Injury = damage to any part of the body due to the application of the mechanical force

Question 2

What are important considerations (in terms of laws of physics) for the intensity of a force on the body?

Answer 2

Human body always subject to forces – gravity, intensity of force obeys laws of physics:

• Force directly proportional to mass of weapon and directly square with velocity of impact
  
  • Kinetic energy = ½ mass x velocity²
• Another important factors is are over which force acts
  
  • Smaller area produces greater impact to any given unit of tissue

Question 3

What can excessive mechanical force cause?

Answer 3

• Compression
  
  • Squashing
• Traction
  
  • Stetching
• Torsion
  
  • Twisting
• Tangential
  
  • Shearing

Question 4

What does the damage of a force depend on?

Answer 4

• Type of injury and nature of target tissue

Question 5

How is a traumatic injury classified?

Answer 5

• Appearance or method of causation
  
  • Abrasion, contusion, laceration, incised wounds, gunshot wounds, burns
• Manner of causation
  
  • Suicidal, accidental, homicidal
• Nature of injury
  
  • Blunt force, sharp force, explosive

Question 6

What are different kinds of “nature of injury”?

Answer 6

• Blunt force, sharp force, explosive

Question 7

What are different kinds of “methods of causation” of an injury?

Answer 7

• Abrasion, contusion, laceration, incised wounds, gunshot wounds, burns

Question 8

What are blunt forced injuries caused by?

Answer 8

Caused by impact with blunt object, such as fist, ground, foot or weapon

Question 9

What are examples of blunt force injuries?

Answer 9

• Contusions (bruise)
  
  • Burst blood vessels in skin
• Abrasion (graze, scratch)
  
  • Scraping of epidermis
• Laceration (cut, tear)
  
  • Tear/split of skin due to crushing
  • Associated with more bruising than incised wound

Question 10

What is the medical term for a bruise?

Answer 10

Contusion

Question 11

What is a contusion?

Answer 11

• Contusions (bruise)
  
  • Burst blood vessels in skin

Question 12

What is the medical term for a graze or scratch?

Answer 12

Abrasion

Question 13

What is an abrasion?

Answer 13

• Abrasion (graze, scratch)
  
  • Scraping of epidermis

Question 14

What is the medical term for a cut or tear?

Answer 14

Laceration

Question 15

What is a laceration?

Answer 15

• Laceration (cut, tear)
  
  • Tear/split of skin due to crushing
  • Associated with more bruising than incised wound

Question 16

Is a laceration or incised wound more associated with bruising?

Answer 16

Laceration

Question 17

What are some patterns of bruising?

Answer 17

• Tramline bruises
  
  • Typical of impact with long cylindrical object
• Finger tip bruising

Question 18

What are some factors that affect the prominance of bruising?

Answer 18

• Skin pigmentation
  
  • Lighter the skin, the more obvious bruising will be
• Depth and location
  
  • Occur more readily over loose skin such as eyebrow, scrotum
• Fat
  
  • Increased subcutaneous fat bruises more easily
• Age
  
  • Children have loose, delicate skin
  • Elderly blood vessels of skin are poorly supported
• Resilient areas
  
  • Buttocks, abdomen bruise less easily than areas with underlying bone which acts as an anvil between bone and inflicting object
• Coagulative disorders
  
  • Thrombocytopenia, Von Willebrand’s disease, haemophilia, liver disease, bone marrow disease

Question 19

Does lighter or darker skin bruise more?

Answer 19

Lighter the skin, the more obvious bruising will be

Question 20

Does bruising occur more readily over loose or tight tissues?

Answer 20

Occur more readily over loose skin such as eyebrow, scrotum

Question 21

What are some areas resilient to bruising?

Answer 21

• Buttocks, abdomen bruise less easily than areas with underlying bone which acts as an anvil between bone and inflicting object

Question 22

What are some examples of coagulative disorders that increase prominance of bruising?

Answer 22

• Thrombocytopenia, Von Willebrand’s disease, haemophilia, liver disease, bone marrow disease

Question 23

What are some examples of patterned abrasino?

Answer 23

• Serrated blade
• Bite
• Strangulation

Question 24

Where do lacerations normally occur?

Answer 24

Normally occurs where skin overlies bone

Question 25

What is a sharp force injury?

Answer 25

Any injury caused by any weapon with sharp cutting edge

Described as superficial or penetrating

Question 26

What are the 2 main kinds of sharp force injuries?

Answer 26

• Incised wounds
  
  • Superficial sharp force injury caused by slashing motion
  • Longer on skin surface than they are deep
• Stab wounds
  
  • Penetrating injury resulting from thrusting motion
  • Wound depth greater than length on the surface

Question 27

What are incised wounds?

Answer 27

• Superficial sharp force injury caused by slashing motion
• Longer on skin surface than they are deep

Question 28

What are stab wounds?

Answer 28

• Penetrating injury resulting from thrusting motion
• Wound depth greater than length on the surface

Question 29

What are some examples of patterned stab wounds?

Answer 29

• Knife with guard
• Screwdriver
• Movement of the blade relative to body