EXAM THIS SAT/SUN

Four types of Blunt Force Trauma?

1. Abrasions

2. Contusions

3. Lacerations

4. Fractures of the skeletal system

What factors affect the severity and apperance of blunt force trauma?

• Amount of force delivered to the body

• Time over which the force is delivered

• Region struck

• Extent of body surface over which the force is delivered

• Type of weapon

• Condition of body being struck

What is an abrasion?

an injury wear the epitelial layer is removed from the skin due to friction against a rough surface (descrution or compression)

Three type of abraisions?

Scrape or brush abrasions (grazes or sliding)

Impact abrasions (pressure abrasions

Patterned abrasion (blunt object)

Patterned abrasion?

Imprint of the offending object is imprinted or stamped on the skin by the crushing effect of the blunt object

Impact abrasions (pressure abrasions)

o The force is directed perpendicular to the skin, crushing it.

o Commonly over bony prominences.(Areas where bones are close to the surface)

o Commonly seen in individuals who collapse and hit their heads on the ground

Scrape or brush abrasions (grazes or sliding)

o Scrapes off the superficial layers of skin

o Leaves a denuded surface

o May extend into the dermis causing capillary bleeding and deposition of

serosanguineous fluid.

o Most common type is a linear abrasion known as a scratch.

o Severe case example is “road rash”

Four Stages of Healing in an Abrasion:

Scab Formation (Serum) - can help indicate victim lived after injury

Epithelial Regeneration and Covering (regeneration of E cells) 72hrs

Subepithelial Granulation (Increased new connective tissue) forms underthe skin (most evident during (9-12dys) (begins 5 to 8)

Regression of Epithelium and Granulation Tissue (apart of the four stages of healing abraisions)

begins at 12dys; becomes thinner with collegen fibers

Gradnulation tissue ; new soft or red tissue formes in the wound bed

CONTUSION OR BRUISE:

o An area of hemorrhage into soft tissue due to rupture of blood vessels caused by blunt

trauma. May also be present in internal organs.

o Contusions may or may not be patterned.

Deep bruises may not be visible externally

o The absence of a bruise or abrasion does not indicate there has been no blunt force

trauma to the specific area

Hematoma

a large focal collection of blood in an area of contusion.

Are deep brusises always seen?

Deep bruises may not be visible externally – incisions may be necessary to document

these injuries.

If there is no bruise or abraision does that mean there wasn’t any force?

The absence of a bruise or abrasion does not indicate there has been no blunt force

trauma to the specific area

The exent and severity of the contusion depends on what?

the amount of force and the structure and vascularity of the tissue ( organ or body part supplied with blood vessels that deleiver oxygen)

Factors influencing the size of a contusion

age, Sex, condition, and health of the victim,

The site and type of tissues struck

What are replication limitations in blunt force injury to skin?

“Skin is not the best medium to record detail.” (Bodziak, 143.)

Photographing this type of evidence can be challenging and problematic due to the

topography of the skin

• Scale

• Perspective

• Tissue Variation

• Body movement

• Hair or clothing

Methods used for aging a bruise:

Histology - Consistent microscopic dating of contusions i

impossible.

Color changes

generally, bruises turn from:

▪ Initially - Red, dark blue, purple, violet or black

▪ Green

▪ Dark yellow

▪ Pale yellow

Postmortem Contusions

May occur if a severe blow is delivered to a body within a few hours after death.

o May result from the surgical removal of the corneas or the globes of the eyes shortly

after death.

o Scleral hemorrhaging may occur at the puncture site after acquiring vitreous.

o Hemorrhage into the eyelids may occur in cases of head trauma with orbital plate

fracturin

How to describe as bruise

as either recent or old

LACERATIONS

A tear in tissue caused by either a shearing or a crushing force. Lacerations can occur

in the internal organs as well as in the skin. Lacerations of the skin tend to be irregular

with abraded and contused margins. Lacerations are caused by blows from blunt

objects or falls.

o Lacerations occur most commonly over bony prominences

Avulsive Injury

A form of a laceration where the force impacting the body does so at an oblique or

tangential angle to the skin, ripping skin and soft tissue off the bone.

o A variation of an avulsive laceration is one produced by shearing forces, where the skin

shows no sign of injury but the underlying soft tissue has been avulsed from the

underlying fascia or connective tissue, creating a pocket that may be filled with a large

quantity of blood.

o An avulsion fracture occurs when an injury causes a ligament or tendon to pull off a

small piece of a bone. A common avulsion fracture involves the hip flexor muscles and

thighbone (femu

Fractures of the Extremities: direct force

a. Penetrating fractures

b. Focal fractures

c. Crush Fractures

Penetrating fractures

The large force acting on a small area – i.e. gunshot

wounds

Focal Fractures

– Small force applied to a small area; resultant fracture is usually transverse, (i.e. bat or pipe blow to forearms)

. Crush fractures

Large force applied over a large area; resulting in extensive soft tissue injuries and often comminuted fractures of the bone, i.e. bumper fractures in motor vehicle–pedestrian accident

Indirect Application of Force is Produced by?

a force acting at a distance from the fracture site

Indirec application forces?

Traction – pulled apart by traction

b. Angulation

c. Rotational

d. Vertical compression

e. Angulation and compression

f. Angulation, rotation and compression – combination

Angulation

bone is bent till it snaps

Rotational

bone is twisted, and a spiral fracture occurs

Vertical compression?

– oblique fracture of the body of a long bone

Angulation and Compression?

– fracture line is curved

Agulation, rotaton and compression

combination of fracture line bone twisted and obliqure fracutre

How many people live in the U.S?

• little over 320 million people

How many cilivians own guns in america?

estimated 310 to 320 million; no exact #

Revolvers are the most common? and How many chambers does it have?

• the most common type of handgun in the United States.

• revolving cylinder that contains several chambers

• each chamber holds a single cartridge

Automactic defnition?

A firearm designed to feed cartridges, fire them, eject their empty

cartridge cases, and repeat this cycle.

Examples: machine guns, submachine guns, selective-fire rifles, including accurate assault rifles.

Semi- Automatic defnition?

A firearm in which each pull of the trigger results in a complete firing cycle, from discharge through reloading. The trigger must be released ( also called "autoloaders" or "self-loaders.")

The discharge and chambering of a round is either blowback operated, recoil operated, or

When an investigator is at the scene of a shooting they should document what?

• shooting note the location of cartridge cases

• Position may determine the location of the weapon at the time of discharge.

• lands and grooves of the barrel of a weapon are responsible for providing a projectile (bullet) with a spiraling motion for accuracy

What is the differences in Calibers in English speaking countries vs. Europe and elsewhere?

In the United States and all English-speaking countries, the diameter of the

hundredths or thousandths of an inch. (.22, .25, .30, .32, .38 and .45 .220)

Europe and elsewhere are designated in millimeters, (6.5 mm, 7 mm, 8 mm, and 9 mm, i.e., 6.35 mm)

perforating mean?

bullet passes completely through an object and does not exist

Four Broad Categories of Gunshot Wounds (DiMaio)

1. Contact

2. Near contact

3. Intermediate

4. Distant

Traditionally entrsncre wounds are said to be?

round to oval in configuration with an eddish to reddish-brown margin of abraded skin—the abrasion ring.

Contract Wounds definition?

The weapon is held against the surface of the body at the time of

discharge

Hard Contact Wound:

The muzzle of the weapon is jammed “hard” against the

skin, indenting it; Wound edges are seared by hot gases of combustion and blackened by the soot deposition; this soot is embedded

• seared skin and cannot be completely removed by washing

Loose-Contact Wound

the muzzle is held lightly against the skin, allowing some gases, gunpowder, and flame to escape, resulting in a narrow zone of searing and blackening around the entrance wound.

• Can be easily wiped away

Angled-Contact Wounds:

The Barrel of the weapon is held at an acute angle to the

skin; the complete circumference of the muzzle is not in contact with the skin; Gas and

soot escape producing an eccentrically arranged pattern. (DiMaio, 1998

Incomplete-Contact Wounds:

Muzzle weapon is held against the skin, but because the body surface is not flat, there is a gap between the muzzle and the skin; A jet of soot-laden gas escapes producing an area of blackened skin;

Most often seen in self-inflicted wounds to the head due to long arms.

Contact Wounds Over BonE

: Contact wounds in regions where a thin layer of skin and subcutaneous fat overlies bone will usually produce a stellate or cruciform appearance.

The unusual appearance of these wounds over bone is due to the effects of gases from the discharge. When the stretching exceeds the elasticity of the skin, it will tear

Near Contact Wounds

The muzzle of the weapon is not in contact with the skin – held a short distance away.

(wide) Soot is baked into the skin and cannot be completely wiped away – unburned powder may be present.

Oval abraison means?

suggest gunshots fired at an angle

Soot Deposition:

(Carbon) produced by the combustion of the gunpowder can contain vaporized metals from the primer, bullet, and cartridge case

Size, Intensity and Appearance of Soot Patterns Depends On

1. Range

2. Propellant

3. Angle of the muzzle to the target

4. Barrel length

5. Caliber of the weapon

6. Type of weapon

7. Target material and the state of the target (bloody or non-bloody)

Four types of contact wounds:

1. Hard

2. Loose

3. Angled

4. Incomplete (A variation of angled)

Semi-automatic firearm only discharge with?

. A semi-automatic firearm only discharges one cartridge with each squeeze of the trigger.

Penetrating bullet means?

Bullet enters an object and does not exit. Perforating: A bullet passes completely through an object.

When a firearm is discharged, the following materials are generally expended from the

end of the barrel?

: bullet, flame, soot, burned and unburned gunpowder

The shape of the abrasion ring around an entrance gunshot wound can?

aid in determining the angle of entrance of the projectile into the body

In self-inflicted cases involving contact or near contact wounds, it is possible to?

observe blood spatter on the hands.

Soot deposits can?

can also indicate as to the position of the weapon when fired.

Circular abraison means?

rings suggest perpendicular directionality

What happens when the distance between the muzzle increases

the pattern of particles on the target increases, and the density of the particle dispersion decreases.(diameter)

According to Dr. Di Maio, the maximum distance out to which powder soot

deposition occurs for most handguns is?

20 to 30 cm (approx. 8 to 12 inches).

this is just here not question

Only test firing of the gun in question with the type of ammunition that was used in

a specific case enables reliable determination of the range of fire in a shooting incident

Intermediate-range wounds mean?

muzzle of the weapon is held away from the body close enough so that powder grains expelled from the muzzle along with the

bullet produces “powder tattooing” of the skin

Powder Tattooing (Stippling):

a pattern of small, permanent, reddish-brown dots or abrasions that can be present around a gunshot wound.

• An antemortem phenomenon indicating the individual was alive.

• but rather punctate abrasions.

• Powder tattooing cannot be wiped off.

• Powder tattooing of the palms of the hands and the soles of the feet is very rare

• Stippling may be due to powder or other materials such as shotgun filler,

intermediary target, etc.

Forensic textbooks generally state that powder tattooing for handguns will extend to a

maximum distance of

18 to 24 inches

Distant Range Gunshot Wounds:

The only marks on the skin are those produced by the mechanical action of the bullet passing through the skin.

• No soot or powder tattooing is present.

• Range determination cannot be made for distant gunshot wounds

Keyhole Defects:

The mechanism of injury used to explain keyhole lesions is that as the

bullet enters the skull tangentially, the bullet is split, one portion entering the cranial

cavity while the other is expelled producing the exit defect.

This is not always the case as a keyhole defect may be produced by a bullet that remains virtually intact.

Exit Wounds

: All have the same general characteristics (contact, intermediate

or distant); typically, larger, and more irregular than entrance wounds and, with rare

exception, do not exhibit abrasion rings.

Shored Exit Wounds:

Observed in unusual conditions; characterized by a broad, irregular band of abraded skin around the wound;

• in these situations, the wound is reinforced by a firm surface when bullet exits

Graze Wound means?

A wound in which a bullet strikes the skin at a shallow angle, producing

an elongated area of abrasion without actual perforation or tearing of the skin

shotguns:

Possess a smooth bore.

o Rifled barrels do exist for single projectiles (slugs).

o Can fire a single projectile (slug) or multiple pellets

Gauge Means?

gauge describes the caliber of the weapon – refers to the number of lead

balls of the given bore diameter that make up a pound.

The most popular gauge of shotgun in the United States is the 12-gauge

Choke means?

• The partial constriction of the bore of a shotgun barrel at the muzzle end to

control shot patterns. A tighter choke equals a smaller pattern of pellets.

Weapons can produce the same gauge no matter what because<

weapons of identical choke will produce approximately the same size patterns at the same range

Choke pattern of pellects are/

• Full

o Modified

o Improved Cylinder

o Cylinder

What is the percentage of child abuse cases where intervention has not happened?

And how many children are hurt or killed in that percentage?

50%: intervention has not occurred.

35%: injured severely or killed.

Child abuse is the second leading cause in?

is the second leading cause of death behind Sudden Infant

1 - 6 months of age.

Child Abuse is the second to accidents of death; what is the age range?

Child abuse is second only to accidents as the cause of death for children 1 – 5 years

of age.

What happens to simone who reports child abuse in good faith?

a person acting in good faith who reports or assists in the investigation of a report of alleged child abuse or neglect or who testifies child abuse or neglect is immune from civil or criminal liability

Day- care employees involves who?

teachers, nurses, doctors, day-care employees, employees of a clinic or health care facility, reproductive services, juvenile probation officers, and juvenile detention correctional officers

What is the timelime for when aprofessional must make a report when abuse is suspected? Can they rely on someone else to write the report?

professional shall make a report in 48th hour after the hour the professional first suspects that the child has been or may be abused or neglected or is a victim

A professional may not delegate to or rely on another person to make the report

Federal law defining child abuse?

: “the physical and mental injury, sexual abuse, or exploitation, negligent treatment or maltreatment of a child under age 18 by a person (health,welfare, against danger)

Most child abuseres fall into what category?

impluse or angry homicide

Munchausens Syndrome by prxoy?

a form of child abuse in which the child us brought to a hospital/doctor for signs of illness in fictitious history also known as gentle homicide

Battered child means?

negelected or starved child

Most commoly cited weapons were?

Hands,feet strangulation, asphyxia

blunt objects, knives, firearms, cutting items

Most child murders occur when?

in the first 2yrs of life with most occuring in the first (1-2years)

Filicide means?

the killing of a child by a parent

Infanticide means?

killing of a child in the first year of life; deliberate or ommision

The most common method of killing newborn infants is by?

suffocaton which usually show no physical signs

Hydrostatic Test:

a method used to determine if a child was born alive

What are some issues with a hydrostatic test?

- Putrefaction issues

- Some infants born alive take only a few breaths and do not aerate

their lungs enough to float.

- Resuscitation issues

• Microscopic examination of lung tissue is very unreliable

Neonaticide means

-The deliberate killing of a child within 24 hours of its birth. The perpetrator is

usually the mother who is young, unmarried and uneducated.

• Occasionally, assisted by a friend or relative, but usually alone with no witnesses.

What was the problems with neonaticide means?

• Major issue: Was the infant alive at the time of birth?

• Milk or food product in stomach establishes live status

Feticide means

an act that causes the death of a fetus

BATTERED CHILD (Baby) SYNDROME:

Injuries to multiple body surfaces and/or injuries in various stages of healing suggest repeated abuse. Deprivation of food and water

Most battered children dies from what?

children die as a result of head trauma, with the next most common

cause of death being abdominal injuries.

What percetage of criminals were abused as children?

90%