Terms

Question 1

Algor Mortis

Answer 1

The cooling of the body temperature after death as it equilibrates with the ambient temperature. Second stage of changes after death. Result of cessation in thermoregulation.

Question 2

Beveling

Answer 2

The result of plug-and-spall fractures caused by fast-moving objects. Sort of cone shaped bone erosion in the direction of the bullet path through the cranial vault caused by the forward moving force of the bullet.

Question 3

Plug-and-Spall

Answer 3

When a high-velocity projectile passes through the bone, a plug of bone in the projectile’s path is displaced and spall are small flakes of the bone that are broken of when the projectile penetrates the other side of the bone.

Question 4

Bloat

Answer 4

Stage two of decomposition which includes the first visible signs of inflation of the abdomen due to various gases produced by bacteria inside the cadaver. Leaked enzumes from first stage begin producing the gases as methane and ammonia.

Question 5

Callus

Answer 5

Bony and cartilaginous material forming a connecting bridge across a bone fracture during repair. Within one to two weeks after an injury, a provisional callus forms, enveloping the fracture site.

A soft callus starts to form, made up of new connective tissue, blood vessels, cartilage and soft spongy bone. By 12 weeks after the fracture, osteoblasts have transformed the soft callus into a hard one.

Question 6

Commingling

Answer 6

The presence of more than one body or skeleton or the intermixing of body parts from more than one individual, such as may occur from a mass disaster or mass graves.

Question 7

Gnawing

Roer

Answer 7

Squirrels and other rodents can chew the ends off bones, to the point of destroying their distinctive shape completely. The gnawing marks can also obscure evidence of trauma to the bone or even be mistaken for weapon marks.

Bite or chew a bone so hard that it gradually disappears

Question 8

High-velocity trauma

Meters per second

Answer 8

Rapid application of force over a small surface area. Produced by bullets from firearms or sharpnel from a blast. Alterations are round, oval or keyhole shaped. Round is seen when projectile impacts perpendicular to the surface of the bone. When is not perpendicular, it is more likely to be oval or keyhole shaped. Another characteristic is beveling or angling of the alteration in the direction of the projectile.
Radiating or concentric fractures. Little or no plastic deformation because force is applied so rapidly that bone does not have time to bend and deform. Greater degree of fracturing and fragmentation.

Question 9

Kerf Marks

Answer 9

Slit made by cutting with a saw. The width of a saw. Describe the thickness of the cut that a saw makes in bone. The teeth of the saw are designed to cut hard material. As saws progresses through material, they create a kerf or groove.

Question 10

Keyhole Defect

Answer 10

Characteristic of a type of entrance wound caused by a bullet striking the surface of a flat bone at a shallow angle. The defect is characterized by a rounded portion with a clean margin where the bullet first perforates bone and a wider area with external beveling on the opposite end.

Unique fracture pattern when a bullet strikes bone at an angle. As a bullet strikes bone at a steep angle (tangentially), the initial defect is typically oval in shape.

Question 11

Livor Mortis

Post-Mortem

Answer 11

Post-mortem sign of death consisting of pooling of blood in the lower portion or dependent parts of the body after death. This results in a dark purple discoloration of the skin. Occurs because the heart is no longer pumping and moving blood through the body. Accordingly, gravity causes the red blood cells to sink and pool in some parts of the body.

Question 12

Low-Velocity Trauma (Slow impact)

Kilometers per hour

Answer 12

Slow load application to the bone over a large surface area. The most important determinant of the morphology of a fracture is the speed. Slow-velocity produce sharp and blunt injuries. A slow force permits the bone to respond an compensate for an increase in stress; when this is removed, the bone may:
* Return to its original shape
* Remain deformed
* Fail

Beatings, motor vehicle accidents, falls from heights, airplance crushes

Question 13

Minimum Number of Individuals (MNI)

Answer 13

The fewest possible number of people present in a skeletal assemblage.

Question 14

Pathology

Answer 14

Study of diseases.
Involves the study and diagnosis of disease through the examination of surgically removed organs, tissues (biopsy samples), bodily fluids, and in some cases the whole body (autopsy).

Question 15

Pits and Punctures

Hoyos, fosas y pinchazos, perforaciones

Answer 15

Bite marks left in the form of holes in bone.
Pits tend to be more superficial and can be located on any part of the skeleton.
Punctures are deeper holes usually found in areas where bone is thin or on the ends of long bones.
Carnivores as wolves, coyotes, foxes, dogs and cats and some omnivores as pigs and bears leave punctures, pits, scoring, furrows on the bone.

Question 16

Post-Mortem Interval (PMI)

Answer 16

Time elapsed since an individual’s death. Is important to establish in forensic investigations to reconstruct death scenes, identify the deceased, and validate alibis.

Question 17

Accumulated Degree Days (ADD)

Answer 17

Accumulated degree-days are a way to measure the passage of time and temperature simultaneously. It uses the heat-time unit as an indicator for estimating the decomposition rate by calculating the mean temperature during the day and subtracting it from the threshold temperature. The accumulated degree is then converted into a period for how long the body has been dead.

Question 18

Purge

Answer 18

Purge is decomposition fluid that is commonly found in the mouth and nostrils.
Decomposition fluid that may exude from the oral and nasal passages as well as other body cavities.
Putrefactive body fluids become forced out of body orifices. It will usually occur 2-3 weeks after death

Question 19

Rigor Mortis

Answer 19

Postmortem change resulting in the stiffening of the body muscles due to chemical changes in their myofibrils. Is usually considered to appear between 1 and 6 hours (average 2–4 hours) after death. Depending on the circumstances, rigor mortis may last for a few hours to several days.

Question 20

Scoring

También: rayado en el hueso por scavenging de carnivoros

Answer 20

Decomposition can be quantified by scoring features such as discoloration, bloating, purging, and the amount of soft tissue remaining, which can then be used to estimate PMI. In some approaches different scoring systems are applied to different areas of the body.

Question 21

Types of fractures

Radiating and Concentric

Answer 21

Radiating fractures are linear fractures that radiate out from the impact site. Related to blunt force trauma.

Concentric fractures are curved or circular lines that surround the impact site. These are associated with high-velocity projectile trauma.

A break that is complete and separates the bone tissue into two pieces is called a simple fracture.
A break that is complete but results in 3 or more bone fragments is called a multi-fragment or comminuted fracture.
A break that does not completely separate is called an infarction.

Question 22

Types of Fractures 2

Answer 22

Radiating fractures typically originate from the point of stress and extend as force dissipates through the bone. Often found in gunshot wounds or sharp force.

Linear fractures (usually) run parallel to the axis of the bone, while transverse fractures run across the axis.

Concentric or hoop fractures occur circumferentially around the point of impact. Common in a depressed fracture.

Radiating and concentric fractures are common in high stress trauma, although concentric fractures can occur without radiating fractures.