Chapter 7 Flashcards
What is the clinical definition of a fall?
An even that results in a person coming to rest inadvertently on the ground (unplanned or unexpected)
What is the research definition of a fall?
Movement of the COM outside of the BOS
What are the 6 main strategies to maintain balance?
1) Controlling body sway
2) Feedback control
3) Feedforward control
4) Anteroposterior stability
5) Lateral stability
6) Multidirectional stability
How does our body control body sway?
The COP works to control the COM moving the body backward and forward
What is feedback control?
Postural control that occurs in response to sensory feedback from an unexpected perturbation
What is feedforward control?
Postural responses made in anticipation of a voluntary movement potentially destabilizing in order to maintain stability during movement
What is a synergy?
Functional coupling of groups of muscles that are constrained to act together as a unit
What muscles contract during ankle strategy?
Forward = POST (paraspinals, hamstrings, gastroc) Backward = ANT (abdominals, quads, tibialis anterior)
What order do the muscles activate during ankle strategy?
Distal to proximal
When is ankle strategy useful?
In small perturbations
What muscles contract during hip strategy?
Forward = large ANT (abdominals, quads) Backward = large POST (paraspinals, hamstrings)
What order do the muscles activate during hip strategy?
Proximal to distal
When is hip strategy useful?
Large, fast disturbances
What 3 strategies are included within anteroposterior stability?
Ankle strategy
Hip strategy
Stepping strategy
What occurs during stepping strategy?
When ankle and hip strategies aren’t enough to maintain balance, a step will restore COM
T/F Hip and ankle strategies cannot be combined.
False, they are combined in a continuous way
What is lateral stability?
An alternative strategy to recover stability in the ML direction