Lecture 7.2 Flashcards
Plant-hopper insect has the fastest accelerating mechanism in the animal kingdom using a ______
gearing system
What are two model imputs for motion models of the human body?
Motion capture and EMG data
Force-plate data
Constant activity of the calf muscles will cause a child to constant walk on their…
toes
A surgical intervention for a patient who walks on their toes is to…
Lengthen Achilles tendon
What is the idea of skin motion artefact?
What is a means around it?
when a marker is placed on the skin, the skin itself. THis means it is not an accurate measurement of how the bones are moving and interacting
Pins can be placed in the bones to get more accurate measurements - But can’t be used on knee
Why is accurate motion of bones important to study in biomechanics?
Develop contact models - can see the stress distribution of joints - imporatnt for diseases like osteoarthritis
What is Bi-plane X-ray Fluoroscopy?
takes video x-ray at high speed
Two planes of X-ray creates 3D information
Muscles that are positioned further from a joint of rotation, have _____ moment arms, ___ leverage and torque
Muscles that are positioned further from a joint of rotation, have larger moment arms, larger leverage and torque
The stabilising or destabilising potential of a muscle is determined by its ___ of _____
The stabilising or destabilising potential of a muscle is determined by its line of action
tendon excursion can be used to measure ___ ____
moment arms
The supraspinatus has a large capacity to elevate the arm in early _______
The supraspinatus has a large capacity to elevate the arm in early abduction
In abduction, deltoid leverage happens ___
late
positive moment arms are _____, negative are _______
positive moment arms are abductors, negative are adductors
rotator cuff tears and lack of use of shouldar can lead to _________
osteroartritis
Reverse total shoulder arthroplasty is…
is a prosthetic joint replacement
the anatomy is reversed however (ball on end of humerus)
The reversed anatomy ____ the moment arms of the shoulder muscles, what does this mean for joint movements?
The reversed anatomy increases the moment arms of the shoulder muscles, what does this cause?
Less force is required to move the arm - more leverage
As we rotate our arms, the scapula moves with the ______
As we rotate our arms, the scapula moves with the humerus
Which muscles moment arm (leverage) is increased significantly in Reverse total shoulder arthroplasty is…
deltoid
There was reduced joint _____, improved ______and _______ in Reverse total shoulder arthroplasty surgery
There was reduced joint dislocation, improved stability and function in Reverse total shoulder arthroplasty surgery
the line of action of the deloid is more superiorly inclined in Reverse total shoulder arthroplasty surgery
This means more superior force in the shoulder - the loading is upward meaning it wants to…
the line of action of the Deltoid is more _____inclined in Reverse total shoulder arthroplasty surgery
This means more ______force in the shoulder - the loading is _______meaning it wants to pull the implant out of the scapula = FAILURE
The smallest, most fragile vertebrae are _______
superior
Normal motion of the neck involves…
complex coupled rotations of segments in all 3 planes of motion
The transverse and spinous processes act to ______ the moment arm of the muscles that attach to them
The transverse and spinous processes act to increase the moment arm of the muscles that attach to them
every muscle has a _______ moment arm in the neck
every muscle has a different moment arm in the neck
What is needed to realistically model a muscle’s torque capacity?
To realistically model a muscles torque capacity, its individual sub-regions(origins/insertions) must be considered for each joint in which they span
