Forensic Trauma

Question 1

Trauma can be applied by 4 basic mechanisms? [4]

Answer 1

• Compression
• Traction (pulling)
• Torsion (Twisting)
• Tangential (Shearing)

Question 2

What are the 3 major categories we use to describe an injury?

Answer 2

• Appearance/method of causation
• Manner of causation e,g, self-inflicted, accident or homicide
• Nature of injury e.g. blunt or sharp force

Question 3

What are the types of blunt force injuries? [3]

Answer 3

• Contusions
• Abrasions (scrapes)
• Lacerations (tear/split in skin due to crushing)

Question 4

Describe some common Contusions Patterns? [5]

Answer 4

• Shoe Treads
• Tyres
• Belt buckle shapes
• Fingers
• Tramline

Question 5

What is tramline bruising? [2]

Answer 5

Impact of a rod-like object pushing blood to either side causing a long area of pallor with strips of bruising to either side

Question 6

What factors effect prominence of bruising? [5]

Answer 6

• Skin pigmentation
• Depth & Location; resilient areas (buttocks)
• Fat (more subcut fat = more bruising)
• Age (kids and elderly)
• Coagulative Disorders

Question 7

What are the different types of sharp force wounds? [2]

Answer 7

Incised - Slashing motion creates a superficial wound longer than it is deep

Stab - thrusting motion creates a penetrating wound deeper than it is long

Question 8

What are the types of defensive injuries? [2]

Answer 8

• Passive where the victim raises arms/legs for protection

- Active where the victim tries to grab the weapon or the attackers hand

Question 9

How do passive and active defensive injuries look different? [2]

Answer 9

Passive shows slices with skin flaps on the back of the hands and forearms

Active shows sliced, shelved wound on the palm & webspaces (mostly the 1st web space)

Question 10

What appearances would suggest a wound to be self-inflicted? [3]

Answer 10

• Common type/place i.e. sharp force wound to wrists, chest and abdomen
• Parallel wounds, multiple wounds and tentative incisions
• If clothes have been lifted prior to the stab

Question 11

Patient presents dead at the scene after being punched to the side of the jaw, what likely happened?

Answer 11

Punch causes a rapid rotation of the neck which ruptures the vertebral arteries as the cross the dura leading to subarachnoid haemorrhage, along with axonal injury to the brainstem resulting in immediate cardiac arrest

Question 12

Patient presents with an intracranial bleed after RTA, whats the likely course the injury took?

Answer 12

Sudden change of direction of motion in an RTA often causes the brain to pull the bridging veins apart resulting in a subdural haemorrhage

Question 13

PAtient presents with a depressed fracture to their temple and signs of rising ICP, whats happened?

Answer 13

the injury to the temple has ruptured the middle meningeal artery resulting in an extradural haemorrhage

Question 14

Define the difference betweeen Diffuse Axonal Injury and Traumatic Axonal Injury?

Answer 14

Often used interchangeably but:

• DAI is clinical and refers to any case with immediate prolonged coma without apparent mass lesion of metabolic abnormality
• TAI is pathological and refers to when axons are damaged by trauma, it can be diffuse or focal

Question 15

What can we tell from a patients injuries after an RTA?

Answer 15

Can tell an RTA often from the specific safety glass wounds.
Can tell if a patient was driving by the pattern of steering wheel bruise/fractures
Can get some idea of the size/shape of the car from a pedestrians injuries

Question 16

How can we tell if there have been post-mortem injuries?

Answer 16

Lack of vital reaction and parchmentation