Postmortem Skin Findings: Discoloration, Bruising, Abrasions
Postmortem Body Surface Changes
Examining the body surface reveals various postmortem changes, including discoloration similar to bruising (pseudo-ecchymotic discoloration):
- Cyanotic Spots: These appear on the face and, more rarely, in the neck region in cases of death from acute cardiorespiratory failure.
- Livor Mortis (Cadaveric Lividity): These discolorations are linked to body position after death, forming only in dependent areas. They are not prominent, the blood is not extravasated outside vessels initially, and there is no laceration or inflammatory reaction. Blood within livor mortis can be washed away with water pressure.
- Putrefaction Spots: In the early stages of putrefaction (involving hemolysis), color changes may appear that resemble bruising upon superficial examination. An incision clarifies the diagnosis by revealing the absence of extravasated blood.
Differentiating Vital and Postmortem Ecchymosis
Blunt trauma applied to a body, particularly in areas with significant vascular engorgement, can cause the rupture of engorged vessels. This results in a spill of a certain volume of blood, which infiltrates the cellular tissue. These postmortem bruises can cause diagnostic difficulties. It is essential to incise the bruised area and examine the characteristics of the extravasated blood:
- Vital Ecchymosis (Antemortem): The blood is infiltrated into the tissue meshwork. It appears firmly coagulated and intimately attached to the tissue, making it impossible to detach or remove by washing with running water.
- Postmortem Ecchymosis: The extravasated blood is liquid or weakly coagulated. The clot is not tightly adhered to the tissues and is easily removed by washing.
Erosions and Excoriations: Medicolegal Assessment
Vital vs. Postmortem Differentiation
The primary differential diagnosis between vital (antemortem) and postmortem erosions/excoriations relies on the presence of a crust. Erosions produced after death typically do not form a crust. Instead, due to dehydration, there is a parchment-like appearance of the affected area. Erosions sustained during life consistently exhibit crust formation.
Exceptions: Postmortem erosions produced in dependent areas already exhibiting livor mortis may allow hypostatic blood to flow and subsequently become crusty. Additionally, insect bites on a corpse can cause erosions that lead to a source of drying, forming a typically dark crust.
Semiology of Erosions and Excoriations
Erosions and excoriations provide valuable medicolegal information based on three criteria:
Topographical Criterion
Erosions and excoriations are usually found on exposed and accessible body parts. The precise location offers valuable data in specific cases:
- Vehicle Impacts: Location indicates the individual’s position when struck and the vehicle’s direction.
- Dragging: Produces large, deep scratches indicating the drag direction and the nature of the surface.
- Suffocation: Characterized by erosions and abrasions caused by fingernails around the nose and mouth.
- Manual Strangulation: Erosions are located on the neck and hold significant diagnostic value.
- Sexual Assault: Genital handling may lead to erosions on the genitals and surrounding regions.
- Fights: Mixed signs of defense and attack are distributed irregularly over the body.
Morphological Criterion
The shape of the erosion can be irregular or patterned. Patterned examples include:
- Rectangular Erosions: Elongated, sometimes with patterns typical of vehicle tires.
- Linear or Tape-Form Erosions: Produced by flogging with whips, canes, etc.
- Shoe Sole Pattern Erosions: Resulting from stomping and kicking. If the traumatic action corresponds to the heel, the erosion has…
Quantitative Criterion
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