Gravity and BOS Flashcards
Body’s COG changes with?
Movement
COG lies closer to the end with the greatest
mass
Gravity’s force is drawn as a
Vector
When moving your arms up and to the left, your COG moves…
Up and leftwards
COG in humans is where?
Women?
about 6in from the pubic symphasis
lower in women
We are most stable when our ____ is over our _____
COG, BOS
In a uniform object (ball), where is the the COG?
in the center
In a non-uniform object (spoon), what changes because of an uneven distribution of weight?
The COG
What does a lower COG give the body?
more stability
What happens when the COG projection falls outside of our BOS?
We fall! (or stabilize with hand)
What do children do when they learn to walk to help them balance
Lower their base of support by using a wide stance
Long sit allows for a larger what?
BOS
When long sitting, what do you use to maintain your COG projection over BOS?
Your upper body
When Iris moves her R hand over her head and forward, her COG moves….
upward and forward
Iris’s MS affects her weight bearing. She has trouble reaching into her cabinets (with her right hand) without falling forward. What should she do?
Use her left hand to balance on counter, and use a long handed reacher
Where should a person’s feet be in relation to a wheel chair when transfering?
Not too close and not too far so that their COG is over their BOS
What should the therapist’s position be when transferring a person out of a wheelchair?
Close to patient, keep back straight, knees bent, (good body mechanics),
COG over BOS!
How should reclining wheelchairs be positioned?
Can only go as far back as will allow the COG to still be over the BOS
Why would one use a “tilt in space” wheelchair?
- relieves pressure
- not in danger of falling
- COG adjusted over large BOS
Where does the COG lie for a person in a wheelchair?
Forward and slightly higher
With an amputation where does the COG lie? (wheelchair user)
more towards the rear
What is there a risk for, for a person with an amputation using a wheelchair?
falling backwards
What is special about the design of a rear-wheel camber
the bottom of the chair rims are further apart
What are the functional benefits of using a rear-wheel camber
You need less shoulder abduction and scapular elevation because the top of the wheel lies closer to the body
