Gait Flashcards
The gait cycle begins with and ends with
Begins with heel strike of one foot, ends with heel strike of the same foot again
What is a stride?
Sequence of events between successive heel contacts of the same foot
Gait cadence and walking speed
110 steps/min
3mph
Stance phase occurs when
The foot is in contact with the ground from heel strike to toe off (60% of the cycle)
Swing phase occurs when
The foot is not in contact with the ground from right after toe off until next heel strike (40 % of the cycle)
What are the 2 period of double-limb support?
Between 0-10% and 50-60% of the gait cycle. The rest of the time only one foot is on the ground. Double-limb support decreases as speed increases, none during running.
What are the 5 events of stance phase?
- Heel strike
- Foot flat (center of mass is behind the base of support), 3. Mid stance (body weight is completely over supporting LE, mid swing on the left)
- Heel off
- Toe off
What are the 3 events of swing phase?
- Early swing - right after toe off to mid swing
- Mid swing - occurs during mid stance phase of opposite LE
- Late swing - time from mid swing until heel hits the ground again
Center of mass during walking vertically and horizontally
Goes up and down 5cm
Side to side 4 cm
Highest with single limb support, lowest with double-limb support
Sagittal plane movement of the pelvis during gait
Described as anterior and posterior pelvic tilt.
Happens at the hip joint (pelvic-on-femoral flex/ext) and lumbosacral joint (pelvic-on-lumbar flex/ext).
Only 2-4 degrees - but important because without this you can change the way forces get dispersed up and down the kinetic chain
Sagittal plane movement of the hip during gait
Hip flexion begins at pre-swing and is flexed 30 degrees at heel strike.
Hip extension of 10 degrees is achieved prior to toe off.
Only have 20 degrees total of hip extension and body does not tolerate losses of hip extension - becomes very problematic for entire LE, you would be loading SI joint and your lumbosacral spine way to much. Loss of hip extension is a predictor for falls in the elderly.
Sagittal plane movement of the knee during gait
0 degrees of flexion at heel strike. Continues to flex another 10-15 degrees during first 15% of gait cycle.
Following flexion, knee will extend to approximately full extension until heel off.
Then the knee will reach 35 degrees of flexion by toe off.
Maximum knee flexion of 60 degrees is accomplished by the beginning of mid swing (need this 60 degrees for functional gait cycle)
Knee flexion is controlled by
Eccentric control of the quadriceps. Without this, patients say that when they go to accept weight they feel like their knee is going to buckle and give out. Puts people at risk for falling on their face.
Sagittal plane movement of the ankle during gait
At heel contact ankle joint is in slight PF.
After heel strike, the foot is placed flat on the ground by eccentric control of PF by the tibias anterior (loss of this is foot slap).
Then about 10 degrees of DF occurs as the tibia moves forward over the foot.
After heel off ankle starts to PF reaching its max of 15-20 degrees after toe off
What primarily drives you forward during gait?
Momentum of toe coming off gets tibia vertically aligned. As it keeps coming forward you need eccentric control of the plantar flexors so it happens in a slow and controlled fashion.