Wound Pattern Analysis and Injury Classification Flashcards

The 'rule of nines' is used in death investigation to:

Answer: Estimate the total body surface area involved in burn injuries

The rule of nines divides the adult body into regions each representing approximately 9% (or multiples thereof) of total body surface area to rapidly estimate the extent of burn coverage.

Which feature most reliably distinguishes an antemortem injury from a postmortem injury?

Answer: The presence of vital reaction including hemorrhage, inflammation, or early healing

Vital reaction—including intradermal hemorrhage, inflammatory cell infiltration, and early tissue repair—occurs only in living tissue, confirming an injury occurred before or near the time of death.

A 'coup-contrecoup' pattern of brain injury results from:

Answer: Blunt force impact causing brain injury both at the point of impact and the contralateral side

In coup-contrecoup injury, the brain sustains damage at the site of impact (coup) as well as on the opposite side (contrecoup) due to the brain's movement within the skull following a blunt force blow.

In a fire-related death investigation, cherry-red coloration of the skin and muscle tissue is most commonly associated with:

Answer: Carboxyhemoglobin saturation from carbon monoxide poisoning

Carbon monoxide binds hemoglobin to form carboxyhemoglobin, which imparts a characteristic bright cherry-red or pink color to skin, muscles, and viscera, indicating the victim inhaled smoke while alive.

The term 'perimortem' in injury timing means the injury occurred:

Answer: At or around the time of death, with ambiguous vital reaction

Perimortem refers to events occurring at or near the time of death, a period when distinguishing antemortem from postmortem injury can be difficult because vital reaction may be minimal or absent.

'Kerf marks' in medicolegal death investigation are most relevant to:

Answer: Analyzing cut bone surfaces in saw-related dismemberment cases

Kerf marks are the grooves and toolmarks left on bone by sawing instruments; analysis of kerf morphology (width, floor shape, striations) can help identify the class of saw used in dismemberment cases.

At what approximate range from the muzzle does stippling (tattooing) typically appear for a standard handgun?

Answer: At intermediate range, generally up to approximately 2–4 feet

For most handguns, unburned and partially burned gunpowder particles retain enough velocity to embed in skin at intermediate distances, typically up to 2–4 feet, though this varies by ammunition and weapon type.