Forensic Science: Bruises and Wounds

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Questions and Answers

What does the shape of a bruise indicate?

The causal instrument that caused the bruise. (correct)

The pain level experienced by the person.

The depth of the bruise.

The age of the individual.

How do color changes in a bruise indicate its age?

From fresh red to blue, then green and yellow stages. (correct)

Colors shift from peripheral blue to central green.

Changing from red to yellow indicates it is old.

A consistent color indicates it is fresh and new.

Which type of tissue is likely to bruise more easily?

Eyelids and genitals. (correct)

Nerves and vessels.

Fibrous tissues.

Palms and soles.

What factor contributes to infants and the elderly bruising more easily?

Delicacy of the skin and health issues. Signup and view all the answers

Which type of bruise occurs due to blunt force impact postmortem?

Contused Wounds. Signup and view all the answers

What characteristic of lacerated wounds helps to identify them?

Ragged or lacerated edges. Signup and view all the answers

What is the main limitation of blood grouping in paternity tests?

It cannot totally confirm paternity. Signup and view all the answers

What can cause deep bruises to take a long time to become apparent?

Location in the body and tissue type. Signup and view all the answers

Which type of wound is classified as causing death to the victim?

Fatal wound Signup and view all the answers

What is a common effect of bruises on individuals with more subcutaneous fat?

They bruise more easily. Signup and view all the answers

What characterizes a bruise or contusion?

It involves extravasation of blood into surrounding tissues. Signup and view all the answers

What is the key feature of a post-mortem abrasion?

It is brown and leathery. Signup and view all the answers

Abrasions typically result from what type of force?

Blunt force Signup and view all the answers

Which type of wound is defined as having a clear edge and is created by a cutting tool?

Incised wound Signup and view all the answers

What legal classification of wounds heals in less than 20 days and leaves no permanent infirmity?

Minor wounds Signup and view all the answers

Which of the following reflects the site of impact for abrasions?

It shows the position of the assailant. Signup and view all the answers

Which characteristic is NOT typical of fabricated wounds?

The age of the wound correlates with the date stated Signup and view all the answers

What type of shock is caused by the nervous system's failure to control blood vessel diameter?

Neurogenic shock Signup and view all the answers

Which type of shock occurs due to severe infection?

Septic shock Signup and view all the answers

What is the typical healing process for incised wounds?

Heals by primary intention. Signup and view all the answers

Which complication involves tissue destruction leading to the release of inflammatory mediators?

Traumatic shock Signup and view all the answers

Which characteristic is NOT associated with incised wounds?

Presence of significant bruising. Signup and view all the answers

In which scenario would you expect to see defense injuries?

In the case of an assault Signup and view all the answers

What is a common misconception about stab wounds?

They can be caused by a blunt object. Signup and view all the answers

Which of the following is NOT a cause of cardiogenic shock?

Severe blood loss Signup and view all the answers

What is a common clinical sign of shock?

Sinus tachycardia greater than 90 beats/min Signup and view all the answers

What changes can be observed in an incised wound within the first 12 hours?

Edges are red and swollen. Signup and view all the answers

Which type of wound is likely to show a clean cut edge with gaping and no bruising?

Stab wound. Signup and view all the answers

Which type of shock can result from a life-threatening allergic reaction?

Anaphylactic shock Signup and view all the answers

What does the presence of trace evidence in a laceration indicate?

Potential involvement of foreign bodies. Signup and view all the answers

How can the age of an incised wound be determined?

Using the date of a related crime. Signup and view all the answers

What is a defining characteristic of fabricated or self-inflicted wounds?

They appear on the body without any trace evidence. Signup and view all the answers

What type of trauma can cause head injuries through rapid rotational acceleration?

Inertial trauma Signup and view all the answers

Which of the following organs is particularly vulnerable to compression and laceration during blunt impact?

Liver Signup and view all the answers

What condition may arise following intestinal damage from abdominal injuries?

Peritonitis Signup and view all the answers

Which type of trauma involves damage caused by a knife or other penetrating object?

Penetrating trauma Signup and view all the answers

In a road traffic accident, which site of injury is most likely associated with stab wounds due to vascular penetration?

All of the above Signup and view all the answers

Signup and view all the answers

Study Notes

Forensic Medicine - Wounds

Wound Definition: A disruption of tissue continuity caused by external mechanical force.
Legal Wound Classification:
- Minor wounds heal in less than 20 days without permanent impairment.
- Dangerous wounds take longer than 20 days to heal and cause permanent impairment.
- Fatal wounds result in the victim's death.
Medical Wound Classification:
- Abrasions (grazes, scratches)
- Bruises (contusions, ecchymoses)
- Lacerations (torn and contused)
- Incised wounds (cuts)
- Puncture wounds (stab wounds)
- Gunshot wounds (GSW)

Forensic Medicine - Abrasions

Abrasion Definition: Damage to the epidermis (outer skin layer) that does not usually involve bleeding; however, the dermis (lower skin layer) may be affected, resulting in minor bleeding.
Causative Force: Blunt force
Medico-legal Importance of Abrasions:
- Shape: Reflects the shape of the object causing the abrasion.
- Site: Provides information about the site of impact (potentially useful in determining the type of assault).
- Direction of Injury: Allows inference of the assailant's position.
- Age of Abrasion: Allows comparison with the date of the assault; early = soft scab; 3 days after = dry scab.

Forensic Medicine - Bruises (Contusions)

Bruise (Contusion) Definition: Extravasation (escape) of blood into surrounding tissues from damaged capillaries or venules, results from blunt trauma.
Medico-legal Importance of Bruises:
- Shape: Indicates the shape of the causal object.
- Site: Indicates location of the impact, but location can shift.
- Age: Age is visually judged by color changes as hemoglobin degrades; typically take 1-4 weeks to disappear from the injury site.
- Size: Bruises in lax tissues are easier to see than in fibrous tissues (e.g., eyelids, genitals bruise easily compared to palms).

Forensic Medicine - Other Wound Types (Lacerations & Incised Wounds)

Lacerated Wounds (Contused Wounds): Splitting of the skin (and tissue) from direct crushing force.
- Characterized by ragged or lacerated edges, abrasions and bruising, crushed blood vessels, possible embedded hairs.
- Less blood loss than incised wounds, but higher risk of infection.
Incised Wounds: Destruction of full skin thickness from contact with a sharp object (knife, razor, broken glass).
- Characterized by regular edges (depending on sharpness of the weapon), often longer than deep, hair cut rather than pulled, and profuse bleeding.

Forensic Medicine - Stab Wounds

Stab Wound Definition: Penetrating injury where the depth is greater than the wound's length.
Causal Instrument: Sharp-pointed objects (knives, daggers, needles).
Medico-legal Importance:
- Shape, Size, and depth,
- Track may reflect weapon width and length,
- Broken tips may be lodged in the wound,
- Absence of bruising or abrasion.

Forensic Medicine - Fabricated/Self-Inflicted Wounds

These wounds are intentionally inflicted.
Often superficial and on readily accessible areas (e.g., extremities, forehead).
Location/type rarely consistent with the circumstances of a crime.

Forensic Medicine - Defense Injuries

Injuries inflicted by the victim when defending themselves.
Examples include punching, kicking, or use of a knife.

Forensic Medicine - Shock

Neurogenic shock: Failure of the nervous system to control blood vessel diameter.
Hypovolemic shock: Loss of blood or body fluids.
Cardiogenic shock: Heart's failure to pump blood.
Septic shock: Due to severe infection.
Anaphylactic shock: Severe allergic reaction
Traumatic shock: Tissue destruction leads to inflammatory mediators.

Forensic Medicine - Embolism

Venous Emboli: Air, fat, or amniotic fluid blockages of vessels.
Arterial Emboli: Nitrogen can cause emboli in scuba diving.

Forensic Medicine - Sepsis

Sepsis is a life-threatening condition that can result from an infection.

Forensic Medicine - Adult Respiratory Distress Syndrome (ARDS)

Acute respiratory failure (ARF) characterized by hypoxemia (low oxygen in the blood), bilateral pulmonary infiltration, with or without an underlying lung disease.

Forensic Medicine - Disseminated Intravascular Coagulation (DIC)

Abnormal activation of the blood's clotting mechanism, leading to widespread clotting and potential organ damage.

Forensic Medicine - Acute Renal Failure

Shock, hemorrhage, and crush injuries can lead to acute kidney failure.

Forensic Medicine - Scars

Permanent disfigurement caused by organ or function loss is an indicator of permanent damage.

Forensic Medicine - Neck Injuries

Very vulnerable from a wide variety of potential injuries, often due to strangulation, pressure, cuts, stabs.
Cuts, stabs, and abrasions are often visible.

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Description

Explore the intriguing aspects of bruises and wounds in forensic science through this quiz. Delve into the characteristics, healing processes, and implications of various types of injuries. Perfect for students and enthusiasts interested in the scientific study of trauma and its effects.