Lecture 6

Question 1

what is the vertical component of a bone do

Answer 1

this is used for rotational motion

Question 2

what is the horizontal component of a bone pointing toward the joint

Answer 2

this would cause stabilizing of the bone

Question 3

what is the horizontal component of a bone pointing away from the joint

Answer 3

this would cause dislocation

Question 4

What does the GRF do to the keen when waling

Answer 4

it will point up toward the center of mass and then cause the knee to adduction

Question 5

what are 3 types of knee moments

Answer 5

normal- with the GRF acting on it normally
Varus- or bow legged and you would need to walk toes out
valgus- this would be knees notching together

Question 6

What hip and knee moment in deadlift

Answer 6

this is truly hip dominant

• large moment arm for hp extensors: lot of torque
• short moment arm for the knee extensors: not a lot of Torque

Question 7

what hip and knee moment in squat

Answer 7

-great balance in demands on knee and hip extensors

• shorter moment arm for hip extensors then deadlift
• longer moment arm for the knee extensors then deadlift

**When the knees are to far forward it will cause shear F to act on them

Question 8

compression at the knee

Answer 8

compression at the patellofemoral joint is the vecctor sum of tension in the quads and the patellar tendon. with increased flexion at the knee, compression increase because of the changed orientation of the force vectors and increased tension requirement in the quads to maintain body position

Question 9

Will need to

Answer 9

WORK through these problems