1. بسم الله الرحمن الرحيم

2. Definition Dr. Doaa Abdel Wahab Degree of burn MEDICOLEGAL ASPECTS
M.L. aspects of thermal injuries
Degree of burn
Definition
Types of thermal injuries
MEDICOLEGAL ASPECTS
OF THERMAL INJURIES
Old classification
Recent classification
A thermal injury is a tissue injury resulting
from the application of heat in any form to
the external or internal surface of the body.
First degree burn
Epidermal degree
1st & 2nd degree
Dry or simple burn.
Scald or moist burn.
Chemical or corrosive burn.
Electric burn.
Radiation burn.
Second degree burn By
Third degree burn
Dermo - epidermal burn
3rd & 4th degree
Fourth degree burn
Dr. Doaa Abdel Wahab
Lecturer of Forensic Medicine & Clinical Toxicology
Fifth degree burn
Deep burn
5th & 6th degree
Sixth degree burn

3. Eaten Singed Wet Wet With mineral acid Present Absent
M.L. aspects of thermal injuries
Dry burn
Scald
Corrosive
Degree
Any degree
1st, 3rd, 4th
1st, 2nd & 3rd
Air passage
Contains soot
No soot
No soot
Eaten
Hair
Singed
Wet
Blood
Thick, viscid & contains COHb
Skin
Dry & charred
Sodden & bleached
Stained & corroded
Flame or heated body
Cause
Steam or hot liquid
Corrosive acid or alkali
Much disfigurement
Thick with disfigurement
Less disfigurement
Scar
Eaten
Clothes
Burnt
Wet
From below upward
From above downward
At & below site of contact
Site & spread
With mineral acid
Charring
Present
Absent
At circumference of burnt area
Over burnt area
Vesicles
Rarely found

4. M.L. aspects of thermal injuries Factors affecting degree of burn
A) Extent of burnt area:
is determined by rule of nine of Wallace.
B) Depth of burn:
The 3rd degree burn is the most serious one.
C) Site of burn.
Neck, abdominal wall or genitalia are more
dangerous than those of the extremities.
D) Age
E) Sex
F) General health.

5. II) Rapid death "within 6-48 hours”:
M.L. aspects of thermal injuries
Causes of death from burn
IV) Death after one week:
II) Rapid death "within 6-48 hours”:
III) Death within 2-7 days:
Immediate causes "within 6 hours“
Neurogenic shock.
Associated accidental serious injuries to vital organs.
Asphyxia (suffocation).
Traumatic asphyxia.
Secondary oligaemic shock.
Secondary toxaemic shock.
Acute oedema of glottis (in the neck).
Pulmonary fat embolism (burn in a fatty area.(
Supra-renal haemorrhage.
Bronchopneumonia.
Inflammation of serous membranes.
Septicemia.
- Tetanus, gangrene and erysipelas.:
- Rupture of an acute duodenal ulcer (at 12th day) (curling's ulcer) (stress ulcer): may be due to hypovolaemia causing devitalization of mucous membrane in addition to the absorbed burn toxins which are excreted by the liver into the duodenum.
-Liver, kidney or heart damage: cell degeneration and necrosis of these organs due to the effect of burn toxins metabolism.

6. M.L. aspects of thermal injuries
Burn vitality
Age of Burn
Antemortem burn
Postmortem burn
Appears
immediately
Erythema
36 hs
48 hs
Line of hyperemia
Present
Absent
Appears
2-3hs
Vesicles
1 w
2 ws
Presence of COHb
Vesicles
Albuminous fluid
rich in chloride
Present
Absent
absent poor in
albumin and chloride
Sepsis
2 – 3
days
36 hs
Vital reaction
Infl., pus
healing
Nil
Superficial slough
1 w
Nothing
But burn
Other causes
Cause of death
Deep slough
3 ws
Soot in URT
Present
Absent
Red
Coppery
Scar
6 m
2 m

7. M.L. aspects of thermal injuries Postmortem Picture of Burn
Complications of Burn
- Particles of soot are present in the air
passage.
Subcutaneous or subserous peticheal hge
may be present .
Haemoconcentration of blood due to loss
of plasma and cherry red colour of the skin.
- Skull may show thermal fracture "fissure
fracture“.
- The body shows evidence of antemortem
burns of various degrees.
The body presents a peculiar attitude;
attitude of defence, boxing or "Pugilistic
attitude".
Crimson red colour of hypostasis.
Generalized visceral congestion and Hge
in the internal organs.
Sepsis
Deformities
Keloid formation

8. Postmortem signs of burn Other postmortem signs of death
M.L. aspects of thermal injuries
Points of differentiation () thermal & traumatic fracture
Traumatic Fracture
Thermal Fracture
The fracture is displaced
Postmortem signs of burn
The fracture is not displaced
The brain is edematous
Other postmortem signs of death
& associated with contused wound in scalp
The brain is shrunken
Extradural haematoma
fill the space
Extradural haematoma
doesn’t fill the space

9. Electric burn Physical Physiological Resistance of body tissue Voltage
M.L. aspects of thermal injuries
Electric burn
Factors influencing the effect of electric current
Physical
Physiological
Resistance of body tissue
Voltage
Humidity
Nature of current
Pathway of current
Anticipation of shock
Duration of contact
General health

10. M.L. aspects of thermal injuries Ventricular fibrillation
Causes of Death
Ventricular fibrillation
Central
Respiratory failure
Peripheral
Cardiac arrest
Cerebral anoxia
Electric burn
Hyperthermic effect

11. Rapid onset of rigor mortis Compression of the stratum corni which
M.L. aspects of thermal injuries
Current Marks
P.M. Picture of Electric Burn
N / E appearance
Microscopic appearance
Rapid onset of rigor mortis
Compression of the stratum corni which
stains deeply with superficial carbonization.
Separation of the cells in the form of slits
(electric channels).
- Elongation of both cells and nuclei.
It is of the same size and shape as the
conductor.
Grayish-white painless areas of aseptic
necrosis.
- They vary from superficial circumscribed
lesions to severe burns with full thickness
tissue necrosis.
Marked hypostasis
Presence of current mark
Internal signs of asphyxia

12. M.L. aspects of thermal injuries
Lightining
Lightning syndrome
Definition
The electric current is DC not AC.
About amperes.
About million volts.
- A single flash lasts 1/1000th of a second.
Characterized by:
Loss of consciousness.
Skin burn (similar to 1st degree burn.
Conductive deafness.
It is the discharge of the atmosphere
potential () clouds, or () clouds and
Earth.