Abrasion

B i.e. Pressure abrasion

Brush burn and friction burn are types of graze (sliding scrapping or grinding abrasion)Q. And patterned abrasions are any imprint or pressure abrasion which reproduce the pattern of causing itQ. Every pattern abrasion is imprint /pressure abrasion but reverse is not true.

B i.e. Ant bite marks

Postmortem ant bites (erosions produced by ants) may produce localized marks which simulate ante mortem abrasionsQ.

Ans. D: Pressure

Ans. Graze abrasions

Ans. Burns

Ans. Graze abrasion

Ans. Patterned abrasion

Ans. Pattern abrasion

Ans. 2-3 days

Ans. Nail scratch

Ans. Secondary injury

Ans. is d i.e., Avulsion

Types of abrasion are : ‑

1)     Scratches (linear abrasion) : It is an abrasion with legnth but no significant width produced by a sharp object e.g., pin, needles, knife, thorn and nail etc. Point scratch is a very superficial incision produced by a sharp or pointed object not sharp enough to incise but pointed enough to produce scratch.

2)   Grazes (Sliding abrasion/scraping abrasion/grinding abrasion) : It is the most common type of abrasion, produced when a broad surface of skin slides against rough surface, e.g., during vehicular accidents. Injury is due to friction. The surface of injury show irregular parallel lines, i.e., furrows or grooves. A violent lateral graze, due to rubbing of skin (as in dragging) is known as brush burn (Gravel rash). Friction burn (Scuff or brush abrasion) occur due to tangential contact with a smooth surface or when the skin is covered by clothing. It is an extensive superficial, reddened excoriated area without bleeding and with little or no linear mark.

3)    Pressure abrasions (crushing or friction abrasions) : Though it is called friction abrasion, it results from pressure of the object on the body with no or little friction (it is a misnomer). It is caused by crushing of superficial epidermis due to inward directed movement of object at around 90° to skin. Example are ligature marks in hanging/strangulation, teeth bites and nail marks.

4)     Impact abrasion (Imprint or contact abrasion) : It is caused by impact (but not pressure) with a rough object, when the force is applied at or near 90° to skin surface. It is depressed below surface unless associated with contusion (bruise).

Ans:B.)Pressure abrasion

This is teeth bite injury

Abrasion

It is a destruction of the skin, which usually involves the superficial layers of the epidermis only.
Types : Abrasions are of four types.

• Scratches
  • A scratch (linear abrasion) is an abrasion with length but no significant width, or a very superficial incision, depending on the agent. 
  • They are caused by a sharp or pointed object, not sharp enough to incise, but pointed enough to scratch.
• Grazes (sliding, scraping or grinding abrasions)
  • They are the most common type. They occur when there is movement between the skin and some rough surface in contact with it. They show uneven, longitudinal parallel lines (grooves or furrows) with the epithelium heaped up at the ends of these lines, which indicate the direction in which the force was applied.
  • These abrasions are commonly seen in a road accident.
• Pressure abrasions (crushing or friction abrasions)
  • They are caused by crushing of the superficial layers of the epidermis and are associated with a bruise of the surrounding area.
  • The ligature mark in cases of hanging and strangulation and the teethbite marks are the examples.
• Impact abrasions (contact or imprint abrasions)
  • They are caused by impact with a rough object, when the force is applied at or near a right angle to the skin surface. The abrasion is slightly depressed below the surface
  • When a person is knocked down by a motor car, the pattern of the radiator grille, a headlamp rim or the tread of the tyre may be seen on the skin, which may contain road dirt, paint flakes, grease, etc
• Impact abrasions and pressure abrasions reproduce the pattern of the object causing it and are called patterned abrasions.

Ans:A.)Graze Abrasion.

Abrasion

• A wound consisting of superficial damage to the skin.
• Types:
• Scratch abrasion
  • Synonym: linear abrasion
  • Sharp or pointed object not sharp enough to cause incised wound, but pointed enough to scratch
  • E.g. thorn, fingernails, tip of knife
  • Clean area at the start of the wound and tags at the end
  • Helps in determining the direction of force
• Graze abrasion
  • Synonyms: grinding or sliding abrasions, brush burns
  • Most common type – Commonly seen in road traffic accidents
  • Occurs when the skin is rubbed (friction) against some rough surface
  • Uneven, longitudinal parallel lines of abrasion are seen
  • Epithelium heaped up at the end of these lines which indicates the direction of force
• Pressure abrasion
  • Synonym: crushing abrasion
  • Sustained pressure of a rough object at 90° – crushing of the superficial layers of the skin
  • No force on impact, but sustained pressure after the object comes in contact with body surface
  • E.g. Ligature mark in hanging and strangulation
• Impact abrasions
  • Synonym: Contact abrasion or Imprint abrasion
  • There is a moment of forceful impact, after that no contact of the object with body
  • E.g: radiator grill mark, tyre tread marks seen in RTA
• Impact abrasions and Pressure abrasions – Patterned abrasions (as the pattern of the object causing the abrasion is reproduced on the body surface)

    e.g. Ligature mark in hanging and strangulation and teeth marks.

Ans:B.)Printed Abrasion.

In a case of hanging neck ligature marks are example of printed abrasion.

Abrasion

• A wound consisting of superficial damage to the skin.
• Scratch abrasion
  • Synonym: linear abrasion
  • Sharp or pointed object not sharp enough to cause incised wound, but pointed enough to scratch
  • E.g. thorn, fingernails, tip of knife
  • Clean area at the start of the wound and tags at the end
  • Helps in determining the direction of force
• Graze abrasion
  • Synonyms: grinding or sliding abrasions, brush burns
  • Most common type – Commonly seen in road traffic accidents
  • Occurs when the skin is rubbed (friction) against some rough surface
  • Uneven, longitudinal parallel lines of abrasion are seen
  • Epithelium heaped up at the end of these lines which indicates the direction of force
• Pressure abrasion
  • Synonym: crushing abrasion
  • Sustained pressure of a rough object at 90° – crushing of the superficial layers of the skin
  • No force on impact, but sustained pressure after the object comes in contact with body surface
  • E.g. Ligature mark in hanging and strangulation
• Impact abrasions
  • Synonym: Contact abrasion or Imprint abrasion
  • There is a moment of forceful impact, after that no contact of the object with body
  • E.g: radiator grill mark, tyre tread marks seen in RTA
• Impact abrasions and Pressure abrasions – Patterned abrasions (as the pattern of the object causing the abrasion is reproduced on the body surface)

Ans. is ‘d’ i.e., Abrasion

Abrasion

• It is a destruction of the skin, which involves the superficial layers of the epidermis only. They are of 4 types:

1. Scratches- its a abrasion with length but no significant width or a a very superficial incision.
2. Grazes-most common. They occur when there is movement between the skin and some rough surface in contact with it.
3. Pressure or friction abrasion- they are caused by crushing of the superficial layers of the epidermis and are associated with a bruise of the surrounding area.
4. Impact or contact abrasion- they are caused by impact with a rough object, when the force is applied at or near a right angle to the skin surface.
5. Patterned abrasion- impact abrasion and pressure abrasion reproduce the pattern of the object causing it and are called Patterned abrasion.