Normal gait Flashcards
What are 3 ways to change the GRF and therefore the knee adduction moment?
- Change COP to make vector more later (toe out walking, lateral wedge, wider stance)
- Bring knee closer (valgus brace, walk with knees closer together)
- Change where GRF ends (trunk lean)
Walking is a test of ________-_____ function.
sensory-motor
What are 4 challenges in normal gait?
- Maintaining upright posture
- Maintaining equilibrium
- Control foot trajectory and ground clearance
- Control of multiple body segments
Gravity tends to produce ______.
flexion
What are the two requirements to maintain upright posture?
- Muscle work required to counteract the effects of gravity
- Joint stability
What are the 2 requirements to maintain equilibrium?
- Coordinated and sufficient neuromuscular responses
2. Adaptability
What are the 2 requirements to control foot trajectory and sound clearance?
- Proprioception/intact tactile sensation
2. Dorsiflexion/compensation
What are the 2 requirements of controlling multiple body segments?
- Proprioception/kinesthesia
2. Adequate neuromuscular coordination
Gait is ________.
cyclical
The instant in which any part of the foot first touches the ground = ?
Initial contact / heelstrike
The period in which the foot is in contact with the ground = ?
Stance phase
The instant in which the entire foot is no longer in contact with the group = ?
Toe-off / foot-off
The period in which the foot is not in contact with the ground = ?
swing phase
How long does the stance phase last for?
60% of gait cycle
How long does the swing phase last for?
40% of gait cycle
_______ = initial contact to subsequent initial contact (same limb)
stride
______ = initial contact of one limb to initial contact of the contralateral limb
step
When is the left step length?
From initial contact of RIGHT foot to initial contact of LEFT foot
When is the left stride length?
From initial contact of LEFT foot to initial contact LEFT foot again
What are the 3 main tasks during gait?
- weight acceptance
- maintenance of stability during single limb support
- limb advancement
What are the 3 objectives of weight acceptance?
- Shock absorption
- Stability
- Preservation of forward progress
What is the most important aspect of pathological gait?
single limb support!
What is the most commonly affected phase of gait in clinical population?
single limb support
What are the 3 objectives of limb advancement?
- Foot clearance over the floor
- Advancement of limb from trailing position
- Preparation for stance
Spatiotemporal measurement values are dependent on what two things?
- Size
2. Age
Lower limb muscles becoming active at specific points of the gait cycle leads to what 3 things?
- Improves efficiency
- Smooth and coordinated gait
- Protects the joints
Is there more vertical or medial-lateral oscillation in the COM during gait?
vertical
What is the main movement of the ankle during gait?
strong PF at toe-off
Dorsiflexion during stance is _______.
passive
Where is the largest ROM of any limb joint during gait?
knee
When are the 2 main period of flexion during knee kinematics?
- Weight acceptance
2. Foot clearance and preparation for heelstrike
Hip remains ______ for the majority of the gait.
flexed
What are the 2 major movements in hip kinematics?
- Stance phase extension
2. Swing phase flexion
Ipsilateral toe off occurs at what % of the gait cycle?
60%
Contralateral toe off occurs at what % of the git cycle?
10%
What is the average self-selected walking velocity?
1.3m/s^2
The largest sagittal plane ROM occurs at which lower limb?
tibiofemoral joint
Gait pattern are/are not stable overtime.
are not!
A single gait cycle is defined as the period from?
initial foot contact of one limb to the subsequent contact of the same limb
The relative percentage of time that the foot is in contact with the ground during normal gait is?
60%
A force applied to a segment that does NOT act through an adjacent joint axis of rotation will create a _____ and tent to ______ that segment.
moment; rotate
Forces examined during gait analysis can be summarized into what 2 types?
- External forces
2. Internal forces
Joints will undergo compression and shearing segments will rotate depending on the ______ and ____ of the forces.
magnitudes; directions
Movements occurs in __ planes.
3
Forces must present in 3 _____ and be about 3 _____.
planes; axes
What is the largest component of the GRF?
vertical
The magnitude of the GRF is very much dependent upon what 2 things?
- Body mass
2. Walking velocity
What is the 2nd largest component of the GRF?
Anteroposterior GRF
The ________ GRF is associated with controlling the magnitude of forward velocity.
anteroposterior
What 3 things will the GRF determine?
- The magnitude and direction of external joint moments
- The required activation patterns for each muscle
- The distribution of load within a joint
In a three-dimensional situation, the GRF has what 3 things?
- Direction
- Magnitude
- Position
_____ ___ ______ = the resultant point of application of force at the foot-ground interface
center of pressure
What is the origin on the GRF vector?
COP
Any force whose line of action that does NOT pass through a joints axis of rotation will cause?
movement?
Movement will rotate the ______ segment with respect to the _____ segment.
distal; proximal
Rotation of the lower limb during gait is proportional o the ____ joint moment.
net
What are the two primary functions of muscle with respect to movement?
- Eccentrically to control or slow movement
2. Concentrically to produce movement
In the ankle, where does inversion and eversion occur?
subtalar joint
What is the major event at the ankle during gait?
forced PF at toe-off
for the majority of stance phase, what is the position of the ankle?
DF
The ____ acts as the basic determinant of limb stability.
knee
What are the two major events that occur at the knee during gait?
- Brief period of flexion during loading response
2. Large flexion period during swing
What are the major events of the hips during gait?
Initiation of hip flexion during terminal stance/pre-swing
