William The Coroner’s Forensic Files

Thursday, 6, October, 2011

This is Why

Filed under: Links to Greatness — williamthecoroner @ 14:51

I like Popehat. The whole snarky thing HERE. And, yanno, I’ve always wanted a M1919BAR, among other neat toys, I should just buy a Bridgeport and be done with it. I’ve already got a 220 line into the basement.

Tuesday, 4, October, 2011

Histology #10

Filed under: Teaching — williamthecoroner @ 15:23

The first examination. With luck, I can use the first three exams to measure their knowledge base and heip build it, and on the final they will be able to answer higher-order questions. That’s the hope, any way.

These ideas come out of Benjamin Bloom and his taxonomy of learning. Basically, Bloom adapted Maslow’s hierarchy of needs, analysing cognitive skills and sorting them on and increasing scale of complexity. These levels range from simple recall to evaluating the worth of material against stated criteria.

Knowledge or recall of data, expresses the natural urge to recall previously learned material. So knowledge, or being told, can be a foundation for very much learning. It provides a basis for higher levels of thinking, but is rote in nature. Insight rides on top of it.
Comprehension, the ability to grasp meaning, explain, restate ideas, means understanding the basic information and translating, interpreting, and extrapolating it.
Application, or using learned material in new situations, involves using information, ideas, and skills to solve problems, then selecting and applying them appropriately.
Analysis suggests separating items, or separate material into component parts and show relationships between parts. It also means breaking apart information and ideas into their component parts.
Synthesis suggests the ability to put together separate ideas to form new wholes of a fabric, or establish new relationships. Synthesis involves putting together ideas and knowledge in a new and unique form. This is where innovations truly take place.
Evaluation is the highest level in this arrangement. Here the ability to judge the worth of material against stated criteria will show itself. Evaluation involves reviewing and asserting evidence, facts, and ideas, then making appropriate statements and judegments.

Figure and explanation from here.

Note: AAR: People do sort themselves out into a perfect bell curve, centred right on the 70 mark. It’s just amazing how this happens.

Monday, 3, October, 2011

Graduate School # 12 Sharp Force Injuries

Filed under: Forensics,Teaching — williamthecoroner @ 15:18

The parts of a knife. How to evaluate and describe forensically a knife wound.

Friday, 30, September, 2011

Sappy Cat(?) Blogging

Filed under: Cat Blogging — williamthecoroner @ 05:17

Wednesday, 28, September, 2011

Did I Miss Anything?

Filed under: People who need pianos dropped on them,Poetry,Social Commentary — williamthecoroner @ 10:18

Did I Miss Anything?

Tom Wayman
From: The Astonishing Weight of the Dead. Vancouver: Polestar, 1994.

Question frequently asked by
students after missing a class

Nothing. When we realized you weren’t here
we sat with our hands folded on our desks
in silence, for the full two hours

Everything. I gave an exam worth
40 per cent of the grade for this term
and assigned some reading due today
on which I’m about to hand out a quiz
worth 50 per cent

Nothing. None of the content of this course
has value or meaning
Take as many days off as you like:
any activities we undertake as a class
I assure you will not matter either to you or me
and are without purpose

Everything. A few minutes after we began last time
a shaft of light descended and an angel
or other heavenly being appeared
and revealed to us what each woman or man must do
to attain divine wisdom in this life and
the hereafter
This is the last time the class will meet
before we disperse to bring this good news to all people
on earth

Nothing. When you are not present
how could something significant occur?

Everything. Contained in this classroom
is a microcosm of human existence
assembled for you to query and examine and ponder
This is not the only place such an opportunity has been
gathered

but it was one place

And you weren’t here

Tuesday, 27, September, 2011

Histology #9

Filed under: Teaching — williamthecoroner @ 21:10

Bone. Osteogenesis imperfecta. Osterpetrosis, osteoporosis. I thought it was going to be muscle, but the syllabus said bone. Have to write a quiz and an exam for next week, and it didn’t help that I have a cold and sound like I’m going through puberty again. Squeek.

Monday, 26, September, 2011

Spontaneous Human Combustion

Filed under: Forensics — williamthecoroner @ 14:26

It doesn’t exist. Really, truly, Mr. Dickens, it does not happen. At all. Ever. No matter what this Coroner in Galway says.

Sheesh. What happens in “Spontaneous Human Combustion”–three things are necessary. 1. the human needs to be drunk or drugged. 2. the person was probably smoking, or had a candle or some form of open flame. 3. The person was fattish, with clothing that can act as a wick. When fat gets hot, it melts. When human fat gets hot and runs onto absorbent fabric, what you have is a wick. Put the wick on a stuporous individual, and let it smoulder, eventually the person will go away and then go out.

I wouldn’t make a cunning plan on it happening, but remember that very fat people have set crematoria on fire (grease fires). It’s not so good a story as spontaneous combustion, but since the human body is 70% water, it’s much more likely.

Graduate School #9

Filed under: Forensics,Teaching — williamthecoroner @ 14:19

Blunt Force Trauma. The basics. This will go on all week.
Blunt Force Injury
I. Definitions
A. Blunt impacts
1. Striking or being struck
2. Severity depends on:
a. Nature of the surface (flat vs. narrow, brittle vs. hard)
b. Amount of body surface (concentration)
c. Amount of force KE= ½ mv2
d. Time
B. Injuries
1. Abrasions (scrapes)
2. Contusions (bruises)
3. Lacerations (tears)
II. Abrasions
A. Scrape.
1. Destruction of surface skin
a. Rough surface
b. Sliding or compression
2. Heal without scarring
3. Pre-vs.-post mortem
a. Premortem red brown
b. Postmortem yellow
4. Types
a. Scrape (scratches, sliding)
b. Brush burn (road rash) large area
c. Impact force perpendicular crushing skin
d. Patterned pattern of the object
5 Healing
a. Scab-epithelial regeneration-granulation-resolution
III. Contusions
A. Bruise
1. Bleeding into tissue
2. Rupture due to pressure–overstress elastic stress
3. Skin or organs
4. May not be associated with impact
5. May be hard to see in dark skinned individuals
B. Focal collection of blood–hematoma
C. Associated with fracture–ecchymosis
1. Battle’s sign
2. Fracture hematoma may be only sign of rib fractures.
D. Factors that influence contusions
1. Age of victim–old people bruise easily
2. Sex Women bruise more easily than men
3. Heath of victim
a. Obese bruise easier
b. Muscular bruise less
c. Bleeding diathesis
d. Loose tissue vs. firm
e. Can be inflicted after death
i Eyebank
E. Colour changes
1. Not reliable for dating.
2. Progression
a. Purple/red/blue minutes to hours
b. Green hours to days
c. Brown
d. Yellow days to months
e. Hemoglobin broken down
IV. Lacerations
A. Laceration is a tear
1. Caused by BLUNT force
2. Tissue stretched, crushed, or sheared
3. Over bony prominence
4. Organs can be lacerated as well as skin
5. Tissue bridges differentiate from incised wound.
6. Long thin objects linear lacs., flat objects irregular lacs.
V. Chest
A. Can have massive injury without external injury
1. Clothing
2. Deformability of the chest
B. Fractures
1. Rib
a. Iatrogenic (CPR)
i. accompanied by sternal fractures
ii. left > right
iii. Check that resuscitation happened
b. Direct
i. Simple, displaced, compounded
ii. Underneath point of impact
iii. May only be seen by hematoma
iv. 1-3 trachea and great vessel injuries
v. 10-12 diaphragm, liver spleen injuries
c. Indirect
i. Squeezing of chest
ii. Front-to-back lateral rib fractures
iii. Back-to-front posterior rib fractures
iv. Side-to-side spine and sternum
v. Big enough everywhere
d. Complications
i. Flail chest
ii. Hemothorax
(a) intercostal arteries
(b) lungs
iii. Pneumonia
iv. Impaling wounds of heart and lungs
2. Sternum
a. Direct trauma
b. Transverse
c. A-P compression
C. Heart & vessels
1. Resulting from
a. Direct force (blows) steering wheel
b. Deceleration
c. Compression (crushing)
d. Blast (over pressure)
e. Indirect force (pressure on abdomen)
2. Severity
a. Nature of trauma
b. Blood in heart
3. Contusions
a. Anterior
4. Laceration
a. Incompressible blood in heart
b. Lead to tamponade
c. Acute 150-300 ml of blood cause death
d. Chronic compensation
e. Increases intra pericardial pressure, inadequate filling
f. Valve lacerations
5. Cardiac concussion
a. Commotio cordis
b. Blow mid-anterior chest
c. Ventricular fibrillation
6. Aortic injuries
a. Vehicle
b. Lacerations–transverse rib or vertebral fractures
c. Site-descending aorta distal to l. subclavian artery
d. Tethered above,
e. Acceleration/deceleration
f. Rule out natural disease
i. Syphilis
ii. Cystic medial necrosis
iii. Atherosclerosis
D. Lungs
1. Secondary to rib fractures
a. Punctures of lung tissue
b. Hemothorax, pneumothorax, hemopneumothorax
i. Open under water
c. Emphysema–gas in tissue
i. Tissue crepitus
ii. Pneumomammary
2. Contusions and lacerations
3. Existing disease
a. Makes things worse
b. Decrease elasticity
E. Diaphragm
1. Lacerations due to rupture
2. Associated with other injuries
3. Stuff is where it shouldn’t be
4. More common on the left
VI. Abdomen
A. Can have massive internal injury without external injury
1. Clothing
2. Deformability
3. Organ consistency
a. Spleen vs. Stomach
b. Distention
c. Tycho Brahe
4. Disease
a. Enlarged spleen with mononucleosis
5. Kind of injury
a. Diffuse (car)
b. Localized (kick)
c. Homicides localized

B. Liver
1. Most frequently injured
2. Right lobe more common than left
3. Severity
a. 27-34 ft/lb capsular tears
b. 106-134 ft/lb crevices of organ
c. 285-360 ft/lb burst and pulped the liver
d. Major vessels and ducts intact
C. Spleen
1. More protected
2. Force against left upper abdomen
3. Disease states
a. Mononucleosis
b. Malaria
c. Typhoid fever
d. Leukemia
D. Pancreas
1. So very well protected
2. Massive abdominal trauma
E. GI
1. Flexible and floppy
2. Distended by food problem for stomach
a. Anterior wall
b. Mostly esophogastromalacia
3. Duodenum
a. Ligament of Treitz
b. Contusions
c. Perforations
4. Colon unlikely
VII. Genito-Urinary
A. Kidneys
1. Rare, location, fat pad
2. Punching
3. Car accidents
4. Train wrecks
B. Bladder
1. Location
2. Pelvic fractures, distention
3. Not a good thing
C. Male genitals
1. External
a. Amputation, crushing
b. Fracture of erectile tissue
c. Cutaneous abrasions, contusions
2. Internal
a. Severity
b. Contusions, lacerations, hematomas
c. Can cause asystole (rarely)
d. Torsion
D. Female
1. External
a. Sexual assault
b. Car crash
2. Internal
a. Rare in non-pregnant
b. Pregnancy
i. MVA
ii. Fall
iii. Assaults
iv. Pelvic fractures
VIII. Skeleton
A. Causes & Kinds
1. Direct trauma
2. Indirect trauma
3. Simple, compound, comminuted

B. Direct
1. Focal fracture
a. Small force striking a small area
b. Transverse
2. Crush
a. Great force striking large area
b. Comminuted
c. Tissue damage
3. Penetrating
a. Great force, small area
b. GSW
C. Indirect
1. Force acting distant from fracture sire
2. Traction-bone pulled apart
3. Angulation-bone bent until snaps
4. Rotational-bone twisted “spiral fracture”
5. Compression fracture
D. Vertebral column
1. Cervical-lumbar-thoracic
2. Where it moves
3. Anterior compression fracture at or near the thoraco-lumbar junction
E. Pelvis
1. Great force
2. Open book spring the symphysis
3. Vertical shear fractures one hemipelvis moves
IX. Extremities
A. Cutaneous
1. Abrasions, contusions, lacerations
B. Deep
1. Muscle, bone, vessels
C. MVA
1. Regular
2. Avulsions
3. Specific to MVA
D. Assault
1. Upper extremity
2. Defense wounds
3. Offensive wounds
a. Hands
b. Contusions of knuckles, fractures of metacarpals
X. Head and neck
A. Scalp
1. Contusions, lacerations, or abrasions
2. Need to shave the scalp
B. Subscalpular tissue
1. Potential space
2. See better than the surface
C. Skull
1. Presence or absence does not correlate with cerebral injury or LOC
2. Begin at point distant to impact
3. 33-75 ft/lb required to make linear skull fracture hard
4. 268-581 ft/lb soft surface (29-45 mph)
5. High velocity penetrating or depressed
6. Low velocity linear, nondisplaced
D. Hemorrhages
1. Epidural
a. Potential space
b. Fracture
i. Squamous temporal bone
ii. middle meningeal artery
c. Lucid interval
i. Symptoms 4-8 hours
ii. Immediate LOC 25%
d. Increased ICP, herniation

2. Subdural
a. Actual space between brain and dura
b. Shearing force on bridging veins
i. Acceleration-deceleration injuries
ii. Brain atrophy
iii. Venous bleeding
iv. Falls or assaults
c. Can be chronic
i. Rebleeding
d. Increased ICP, herniation
i. Acute 50 ml
ii. Chronic weeks
iii. Organization
iv. Can be used for tox.
3. Subarachoid
a. Leakage of blood from capillaries
E. Brain
1. Contusions
a. Location
i. Frontal
ii. Temporal
iii. Anterior cranial fossae
b. 6 types
i. Coup
ii. Contre-coup
iii. Fracture
iv. Intermediary
v. Gliding
vi. Herniation
2. Lacerations
a. Children more often than adults
b. Usually associated with massive skull trauma

3. Diffuse axonal injury
a. Immediate prolonged coma (6 hours w/o ICH or mass lesion)
b. Sudden acceleration-deceleration injury shearing of axons
c. Rotational injury
d. Axonal bulbs
4. Concussion
a. Mild to severe
b. Severe: LOC, amnesia
5. Cerebral edema
a. The killer
b. Herniation

Saturday, 24, September, 2011

Ya Think it’s Easy, Icarus?

Filed under: Natural History — williamthecoroner @ 01:47

An Eagle Owl landing at 1000 frames/sec. Wow. Hat tip, Lex.

Friday, 23, September, 2011

Graduate School #9 Natural Disease

Filed under: Teaching — williamthecoroner @ 18:20

Speaking of Natural disease, I felt terrible, so I went home and had hot tea, a cat, and a nap. Things are much better now, thank you very much.

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