FULL DESCRIPTION

1. ABRASIONS
PRESENTED BY :- SUBMITTED TO :
RUCHIT PATEL
GOVT. MEDICAL COLLEGE,
BHAVNAGAR

2. INTRODUCTION
• Type of MECHANICAL injury.
• Due to BLUNT force.
• Destruction of the skin which usually invloves
the SUPERFICIAL LAYERS of the EPIDERMIS
only.
• Also known as GRAVEL RASH.

3. MECHANISM
• Caused by :-
(a.)FRICTION against a rough surface
(b.)By COMPRESSION, such as
- lateral rubbing action by a blow
- by being dragged in a vehicular accident
- fingernails
- thorns
- teeth bite
The epidermal cells are flattened and their nuclei are
elongated.
The rougher the surface, and the more rapid the movement of
the skin over it, the deeper is the injury.

4. MECHANISM
• The exposed raw surface is covered by exudation of
lymph and blood which produces a protective covering
known as a SCAB or CRUST.
• They are simple injury, bleed slightly, heal rapidly and
SCAR IS NOT FORMED.

5. TYPES OF ABRASIONS
• Scratches
• Grazes
• Pressure abrasions
• Impact abrasions

6. SCRATCHES/ LINEAR ABRASION
• Has length but no significant width.
• Caused by SHARP/POINTED objects like :-
- fingernails
- pin
- thorn
• A scratch produced from tip of a knife or razor is called as
POINT SCRATCH.

7. GRAZES/GLIDING/SLIDING ABRASION
• Most common type.
• Movement between skin and some rough surface in
contact with it.
• Uneven, longitudinal parallel lines with epithelium
headed up at the ends of these lines, which indicates
the direction in which the force is applied.

8. • The furrow may be broad at one end and
narrow at the other end.
• Commonly seen in road accidents.
• a glancing kick with a boot is also a graze.

9. PRESSURE ABRASIONS
• Caused by CRUSHING of the superficial layers of the
epidermis.
• Associated with a bruise of the surrounding area.
• If movement of the instrument is around 90 degrees to
the skin, pressure abrasion is produced.
• Force of impact – less
• Duration - more
• Examples :-
- ligature mark in cases of
hanging and strangulation.
- teeth bite marks.

10. IMPACT ABRASIONS
• Caused by impact with a rough object when
force is applied at right angle to the skin
surface.
• Force of impact- high
• Duration – less
• Example – a person getting hit by a car.

11. PATTERNED ABRASION
• Subtype of impact/ pressure abrasion
• Reproduce the pattern of the object causing it.
• Force is applied at right angle to skin surface.
• Examples-
- imprint of bicycle chain
- ropes

12. AGE OF ABRASIONS
• Fresh – Bright red
• 12 to 24 hours – Bright red scab
(blood and lymph dries up)
• 2 to 3 days – Reddish-Brown scab
• 4 to 7 days – Dark brown to Brownish-Black
scab
• After 7 days – Scab dries and falls off, leaving
depigmented area with gets pigmented gradually.

13. DIFFERENCE BETWEEN ANTEMORTEM
AND POSTMORTEM ABRASIONS
ANTEMORTEM ABRASIONS
• SITE- Anywhere on the
body.
• COLOUR- Bright reddish-
brown.
• EXUDATION- More
• SCAB- Raised
• MICROSCOPIC- Intravital
reactions and congestion
seen
POSTMORTEM ABRASIONS
• Usually over bony
prominences.
• Yellowish translucent.
• Less
• Below the level of skin.
• No intravital reactions and
no congestion.

14. MEDICOLEGAL IMPORTANCE
• Give idea about the site of impact and
direction of force.
• Patterned abrasions help in identifying the
object of injury.
• The age of the injury can be determined.
• Character and manner of the injury can be
known, e.g. in SEXUAL ASSAULT, abrasions
may be found on the breasts, genitals, inside
of the thighs, and around the anus.

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