[gatagato]

One of the most commonly encountered types of trauma resulting in serious injury or in traumatic death is blunt force injury. Blunt force injury is defined as injury resulting from
impact with a blunt object, i.e., one that does not possess any sharp edges. Examples of blunt objects include hammers, baseball bats, fists, the interior surfaces of vehicles, roads, trees, floors, walls, furniture, and even fluid objects such as bodies of water (if the speed of impact is sufficiently high).

Blunt force injuries are made up of five subgroups, each representing
a different response to the transfer of force from a blunt object onto or into the body. Many blunt force injury cases, such as those that occur in vehicle collisions and following falls or jumps from heights, involve forces that are associated with
sudden deceleration (or acceleration in certain motor vehicle–related cases) which may significantly contribute to the overall injuries. Thus, the term ‘‘blunt force injury’’ should also encompass acceleration/deceleration forces in some situations.


Abrasions
Abrasions are also known as scrapes, scratches, or grazes. They result from a blunt object impacting the surface of the skin with disruption and loss of superficial layers. Abrasions are only found
at the actual site of impact with a blunt object but do not always occur with blunt impact; for example, if the impact site is protected
by heavy clothing.
The size and shape of abrasions varies greatly depending on the force of impact and the amount of skin surface involved.
Theymay reflect the direction of the impact andmay not bleed if they are very superficial and do not involve the dermis.

Contusions
Contusions or bruises occur when a blunt force has caused disruption of blood vessels with escape of red blood cells into the surrounding tissues.
A bruise may occur in isolation or it may be associated with abrasions and lacerations.
It may show the outline of the impacting object, which may resemble tram tracks if the object is linear.
A contusion may not appear immediately
if the area of bleeding is deep within the dermis or
subcutaneous tissues.
Unlike abrasions, contusions may occur
at sites of impact, as well as at sites distant from the impact site due to tracking of blood through the tissues. The aging of bruises
is notoriously difficult despite the ‘‘standard’’ color changes described in a number of older textbooks. Dating of bruises from photographs should not be attempted.

Lacerations
A laceration refers to splitting of tissues from blunt force or acceleration/deceleration injuries. It is not found with sharp force injuries.
A laceration of the skin may be linear, jagged,
irregularly shaped, or occasionally patterned and may be associated with abrasions and contusions. Lacerations typically have irregular tissue bridges crossing from one side to the other, a feature that is not found with an incised wound from a sharp object, where all tissues are neatly divided.
Lacerations most often occur at the site of blunt force impact; however, they may also be found at sites distant to the impact due to stretching of tissues. Lacerations from blunt force and acceleration/deceleration also commonly involve internal organs and tissues.

Fractures
Fractures refer to the breaking of a bone (or cartilage) and usually result from significant blunt force. Fractures are classified in a variety of ways. If a fracture near the skin surface is
covered by intact skin it is classified as ‘‘closed’’, compared to the case when there is a laceration of the overlying skin with communication
between the fracture and skin surface, which is
classified as an ‘‘open’’ or ‘‘compound’’ fracture. These fractures are more susceptible to infection. Alternatively, a ‘‘simple’’ or ‘‘complete’’ fracture refers to a linear (straight line) fracture that
runs across the bone shaft, involving both sides (cortices) of the bone.
An ‘‘incomplete’’ fracture involves only one side of the bone shaft. ‘‘Greenstick’’ fractures are specific to childhood where the bone bends rather than breaking. A ‘‘buckle’’ fracture is an incomplete fracture where one cortex collapses or buckles.
A ‘‘spiral’’ fracture occurs in long bones from a rotational force.
It has a helical shape, twisting around the long-axis of the bone shaft. A ‘‘comminuted’’ fracture is one that has many separate fragments of bone.

Avulsions
An avulsion injury occurs when a blunt force has resulted in
separation of an organ or body part from the rest of the body. An
example involving the limbs is an amputation injury where an
entire extremity or portion thereof is severed from the body.
Decapitation represents the most extreme example of an avulsion injury, where the head is separated from the body. Not all avulsion injuries are the result of blunt force, as similar injuries may occur with sharp force, e.g., decapitation by
a guillotine. However, a significant number of these types of injuries are related to severe blunt force/deceleration force that may be seen with pedestrian verses train, or motorcycle verses
tree accidents. In these cases, total body transection may be observed. Avulsion of internal organs may also occur with cases of severe blunt force/deceleration.

Head Injuries
Many deaths due to blunt force trauma are caused by head and brain injuries.
Craniocerebral trauma can be used as a collective
term to describe injuries to the head, including the skull, and the brain. If there are no skull fractures, brain injuries are sometimes referred to as ‘‘closed head injuries.’’ If there are significant neck
and upper spinal cord injuries, the terms craniocerebral and cervical trauma can be applied. Blunt trauma injuries to the head may involve the following (commencing with the outermost
layers): skin, subcutaneous and subgaleal tissues, skull (cranium) and facial bones, dura, subdural space, subarachnoid space, and, finally, the brain.

Neck, Spinal Cord, and Vertebral Artery Injuries
The neck is vulnerable to blunt trauma which may compromise
blood flow to the brain or damage the integrity of the spinal cord.
A broken neck may result from blunt force injury with fracture of the cervical vertebral column, causing contusion, laceration, or transaction of the cord. Disruption of the atlanto-occipital
joint, where the occiput, or base of the skull, connects to the first cervical vertebrae, may result in similar injuries. A blow to the side of the head or face, with abrupt twisting or sideways flexion
of the neck, may cause laceration of the vertebral artery with resultant lethal basilar subarachnoid hemorrhage.




Fig. 12.1
An example of many different types of abrasions, including linear and rounded


Fig. 12.2
Multiple abrasions of various sizes and shapes


Fig. 12.3
Linear parallel abrasions resulting from striking an automobile windshield


Fig. 12.4
Multiple linear and confluent abrasions on a murder victim’s abdomen, produced when her body was moved (dragged). Note the yellow
discoloration, indicating peri- or postmortem occurrence


Fig. 12.5
An abrasion with peeled-up superficial layers of the epidermis. Their location toward the left of the abrasions shows that the direction of
force was from right to left in the photograph


Fig. 12.6
Linear abrasions from contact with a road surface


Fig. 12.7
Parallel abrasions on the flank and arm from dragging along a road surface (so-called ‘‘brush’’ abrasions). The yellow discoloration
indicates that there was little blood flow to the skin injuries when the abrasions occurred


Fig. 12.8
An example of more extensive confluent and dried
abrasions on the trunk of a pedestrian, sometimes
referred to as ‘‘road rash’’ or ‘‘brush’’ abrasions


Fig. 12.9
An impact contusion of the chest


Fig. 12.10
A relatively small impact contusion of the arm


Fig. 12.11
A scalpel incision of a contusion at autopsy, allowing visualization and documentation of the hemorrhage within the subcutaneous fat


Fig. 12.12
An example of senile ecchymosis or easy bruising of the arms of the elderly associated with fragile skin and subcutaneous tissues


Fig. 12.13
Bilateral periorbital ecchymoses (raccoon’s eyes), resulting from basilar skull fractures sustained in a fall


Fig. 12.14
An example of Battle’s sign, or bruising behind the ear due to basal skull fractures


Fig. 12.15
Grey-Turner’s sign, bruising of the flanks,
indicating extensive internal (retroperitoneal)
hemorrhage


Fig. 12.16
An area of red bruising around the umbilicus,
so-called Cullen’s sign, associated with intraand
retroperitoneal hemorrhage


Fig. 12.17
Opening of the abdomen in the previous case with
a positive Cullen’s sign (>Fig. 12.16), revealing
extensive intraperitoneal hemorrhage from
a lacerated liver


Fig. 12.18
A multicolored bruise known to have occurred
7 days prior to death


Fig. 12.19
A 6-day-old bruise showing brown discoloration


Fig. 12.20
Purple-blue bruising with swelling of the scrotum in a patient in a mental institution. The perpetrator was a male nurse


Fig. 12.21
A contusion of a heart from blunt chest trauma. The heart also has a large amount of epicardial fat


Fig. 12.22
A laceration of the scalp. Note the somewhat jagged appearance, as well as the marginal abrasions. The hair has been shaved to
demonstrate the full extent and nature of the wound


Fig. 12.23
A laceration with extensive associated
abrasions


Fig. 12.24
Extensive lacerations of the scalpwithminimal
associated abrasions


Fig. 12.25
A scalp laceration with minimal marginal abrasions but with tissue bridging toward the left end (arrow)

Fig. 12.26
A laceration with prominent tissue bridging


Fig. 12.27
Scalp laceration (a) with prominent undermining (b)



Fig. 12.28
Linear and curved lacerations of
the scalp revealed by shaving the
hair of a homicide victim who died
from blunt craniocerebral trauma


Fig. 12.29
A characteristic laceration from
blunt trauma to the head
extending through to the surface
of the skull


Fig. 12.30
A series of linear lacerations behind the ear from kicking


Fig. 12.31
Numerous stretch lacerations of the inguinal (groin) region in a pedestrian struck from behind. These lacerations are yellow
with minimal hemorrhage, indicating that the blood pressure most likely immediately dropped on impact (due to severe internal injuries)


Fig. 12.32
Laceration of the perineum following blunt abdominal trauma in a vehicle accident


Fig. 12.33
Extrusion of small intestine through a lacerated perineum following blunt abdominal trauma from impact with a vehicle



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486 12 Blunt Force Injury Deaths
The Atlas of Forensic Pathology for Police, Forensic Scientists, Attorneys and Death Investigators (2012)

[souris]

nice post thank you

[TheFallOfTroyML]

wow ultra amazing post !

thanks a lot, great pics, great captions

[Lion-hearted Girl]

Great post Gato!

[donnerkebab]

:xyxth umbs:

[Lyndsay]

its not the fall that kills you, its the sudden stop.

[Pyramid_Head]

That was one serious hairy snatch.

[wujuan]

thank you.

[kellyhound]

great post and info never knew they called it raccoon's eyes

[Kelseecat65]

Awesome post!! That last one... it makes my lady parts cringe. OUCH.