warm-up does anyone know why weight lifting can build stronger bones and prevent osteoporosis?
TRANSCRIPT
Warm-upWarm-up
Does anyone know why weight lifting can build stronger bones and prevent osteoporosis?
You will need to know: 1) What is forensic anthropology?2) How can bones be used to identify age? Sex?3) What bones are best for identifying age and sex for adults? Children?4) Use a conversion table to estimate the height of an individual.5) Define antemortem, perimortem, and postmortem.6) Know the name and location of the long bones (ulna, radius, femur, etc.)
ObjectiveObjective
Use knowledge of how bones heal to determine whether an injury occurred antemortem, perimortem, or postmortem.
Reading ActivityReading Activity
Read the 1st paragraph. What is the difference between antemortem,
perimortem, and postmortem?
Read the remainder of the 1st page What is a “green” bone? Which stage (antemortem, perimortem, or
postmortem) do we see impressions from tools?
Reading ActivityReading Activity
Read the next 2 paragraphs (p. 2) What are the two wrist injuries mentioned in
the article?
Read the rest of the article. How can we distinguish perimortem from
postmortem when analyzing bones?
Healing Nature of Healing Nature of BonesBones
Bones have the ability to heal
Key Players: Osteoclasts – break down bone Osteoblasts – build new bone Chondroblasts – build new tissue
http://www.exogen.com/physicians/how-it-works/
InflammationInflammation
1) Fracture Hematoma forms – helps keep the bones aligned & cuts off oxygen from the fractured bone (killing it)
Source: http://science.howstuffworks.com/life/human-biology/heal-broken-bones.htm
Soft CallusSoft Callus
Several days later, the fracture hematoma turns into a soft callus Fibroblasts develop collagen & chondroblasts
begin developing fibrocartilage Transforms from soft callus to fibrocartilage
callus – bridges gap between bones (3 wks)
Source: http://science.howstuffworks.com/life/human-biology/heal-broken-bones.htm
Bone Callus (Hard Bone Callus (Hard Callus)Callus)
Formation of the bone callus Osteoblasts begin building new bone 3-4 month process Provides enough stability for the bone to finish
healing
Source: http://science.howstuffworks.com/life/human-biology/heal-broken-bones.htm
RemodelingRemodeling
Not done yet… Osteoclasts and Osteoblasts spend months
remodeling the bone by replacing bone callus with compact bone
Overtime, remodeling reduces the bulge
Weight-liftingWeight-lifting
Weight-lifting causes small fractures to occur in our bones, but DON’T panic!
These fractures signal osteoclasts to come remove the damaged bone and osteoblasts to build new bone.
Overtime, you end up with stronger, healthier bones!
Also, remember, the more muscles your have, the more bone you need at your joints to hold those muscles, further strengthening your bones.
TerminologyTerminology
Antemortem – before death
Perimortem – occurs at time of death
Postmorem – occurred after death
AntemortemAntemortem
Injuries that involve Bruising –occur only while the heart is beating Healing – which would not occur without time
for the living body to repair the injury.
Bone remodeling – bulge from an old fracture
History in the bonesHistory in the bones
Often anthropoligists are asked to determine whether an injury occurred antemortem, perimortem, or postmortem
Antemortem injuries could show signs of long time abuse, old fractures, and recent injuries
Why might a forensic anthropologist be interested in antemortem injuries?
Rib started to growRib started to growaround the .22 caliber around the .22 caliber
bullet. That's antemoretembullet. That's antemoretem
AmputationsAmputations
Not all antemortem fractures are from accidents or attacks Ex: Amputation – partial healing of bone, but
not enough living tissue to regenerate the bone.
Perimortem InjuriesPerimortem Injuries
Occur at time of death – often provide evidence of cause of death &/or murder weapon
Weapons can leave imprints in perimortem injuries
Occur without the body attempting to heal (bruising, clotting, etc.)
What this means…What this means…
Bones have no time to heal, so fractures are clean and sharp
As seen in the bones of an American Indian woman who was hit by a truck
The trauma from the impact shattered her femur
PostmortemPostmortem
These injuries usually occur when bodies are moved or by environmental factors.
Fractures are jagged and rough, with a random breaking pattern.