Week 2 Flashcards
Lower Body Mechanics and Gait
Describe the Relative Motions that occur during Sacral Counter Nutation.
Extension of Sacrum
Innominate External Rotation
Femoral External Rotation
Describe the Relative Motions that occur during Sacral Nutation.
Flexion of Sacrum
Innominate IR
Femoral IR
Describe Pelvic Orientation with Anterior Tilt
-No Innominate Bone action
-Movement though lumbar spine
-Femoral Internal Rotation
Describe Pelvic Orientation with Posterior Tilt
-No Innominate Bone Action
-Movement through lumbar spine
-Femoral External Rotation
How can you visually distinguish between True Relative Motion and Orientation?
True Relative Motion is hard to see because it is subtle.
Rule of Thumb: If it looks bad, its likely orientation.
Describe the Hip Flexion Movement Arc
Internal Rotation
-Sacral Nutation
-Femoral IR
-Tibial IR
-Foot Pronation
Describe the Hip Extension Movement Arc
External Rotation
-Sacral Counter-Nutation
-Femoral ER
-Tibial ER
-Foot Supination
Why is Gait primarily a Pelvis-on-Femur sequence?
Because it occurs in a Closed-Chain environment
Relative motion is maximized with both feet on the ground
Describe the sequence of the Gait Cycle
Heel Strike - Foot Flat - Mid Stance - Late Stance - (Swing)
Describe the Concentric activity during Heel Strike to Foot Flat.
Limited Concentric Activity at the Hamstrings and Obliques
Describe Eccentric Activity during Heel Strike and Foot Flat
Eccentric heavy because we are slowing ourselves down at heel strike to allow for opposite-side advancement.
Eccentric activity at
Glute max, Quads, Calves, Hip Abductors, Erector Spinae, and Tibialis Anterior
What happens to the Structures at the Pelvis during Heel Stike to Foot Flat (0-20%)?
Sacrum - Nu’ing from Co Nu
Innominate Bones - IR’ing from ER
Hip Joint - ER’ing from ER
What happens to the structures BELOW the Pelvis during Heel Strike to Foot Flat (0-20%)?
Femur - IR’ing from ER
Tibia - IR’ing from ER
Foot - Pronating from Supination
Big Toe - ER’ing from ER (Spreading out)
What happens to the structures of the Pelvis upon Heel Strike?
Pelvis - Turned Away from Stance Leg
Sacrum - Counter Nutated
Innominate Bones - ER’d
Hip Joint - ER’d
What happens below the Pelvis upon Heel Strike?
Femur - ER’d
Tibia: ER’d
Foot: Supinated
Big Toe: ER’d (Spread Out)
What happens at the Pelvis upon Foot Flat?
Pelvis - Turning Away from Stance Leg
Sacrum - Nutating from (from Co-Nu)
Innominate Bones - IR’ing from ER
Hip Joint - ER’ing from ER
What happens below the Pelvis upon Foot Flat?
Femur - IR’ing from ER
Tibia: IR’ing from ER
Foot: Pronating from Supination
Big Toe: IR’ing from ER (Moving toward second toe)
What happens immediately at the Pelvis & Femur with Heel Strike
The Pelvis & Femur immediately move toward Internal Rotation
What muscles are Concentrically contracting between Foot Flat and Mid-Stance
-Proximal Fibers of Hamstring
-Anterior Gluteus Medius
-Tensor Fasciae Latae
-Quads
-Adductors (in creating adduction)
-Tibialis Anterior
What muscles are Eccentrically contracting between Foot Flat and Mid-Stance?
-Glute max
-Calves
-Hip abductors
-Tibialis Posterior
What is happening at the structures of the Pelvis between Foot Flat to Midstance (20-40%)
-Sacrum: Counter-nutating from Nutation
-Innominate Bone: ER’ing from IR
-Hip Joint: IR’ing from ER
What is happening to the structures BELOW the Pelvis between Foot Flat to Midstance (20-40%)
-Femur: ER’ing from IR
-Tibia: ER’ing from IR
-Foot: Supinating from Pronation
Big Toe: Moving towards second toe
When does Heel Strike end?
Heel Strike ends with big toe ground contact
When does Foot Flat end
Foot Flat ends with re-supination of foot
