Gait Assessment Flashcards
Gait Assessment
Development (Rolling):
- ? - 4 months
- ? - 8 months
Rolling:
- Prone to supine = 4 months
- Supine to prone = 8 months
Development (Sitting):
- ? - 4 months
- ? - 8 months
Sitting:
- Supported (tripod) sitting = 4 months
- Independent Sitting = 8 months
Gait Assessment
Development (Prone Progression):
- ? - 4 months
- ? - 8 months
Prone Progression:
- Prone Extension = 4 months
- Creeping Position = 8 months
Gait Assessment
Development (Walking):
- 12 months = ?
- 8 months = ?
Walking:
- Phase One (Balance) = 12 months
- Phase Two (Refinement) = 16 months
Gait Assessment
Step vs. Stride?
Step = the distance or process of transitioning from heel strike on one foot to heel strike on the other.
- 28 inches (72 cm)
- Foot angle = 5-7 degrees
Stride = the distance or process from one heel strike all the way to heel strike again on the same leg.
- 56 in (144 cm)
Step Width = 3.5 in (8-10 cm)
Gait Assessment
1st period of the gait cycle?
(1) Initial Contact / Heel Strike: The first period is defined as the instant the foot contacts the ground.
- At initial contact, the foot should strike the ground posterior and slightly lateral, with:
- the ankle in slight supination
- the knee relatively straight, and
- the hip close to its maximal amount of flexion at 20 to 30d.
When the foot hits the ground, the ground reaction force passes posterior to the ankle, posterior to the knee, and anterior to the hip, necessitating activation of the tibialis anterior, quads, and hip extensors, and because our bodies increase co-contraction whenever we need control, we see on the right of your slide that the body turns on a lot of muscles at a low level to brace for impact; however, it gives a little extra mustard to the tibialis anterior, as it is needed for eccentric control to lower the forefoot down to the ground.
Hip = 20 degrees of flexion
Knee = 5 degrees of flexion
Ankle = 0
Gait Assessment
2nd period of the gait cycle?
(2) Loading Respone / Foot Flat
[The 2nd period of gait begins with foot contact and will end with opposite limb toe off]
- Immediately after, at loading response, the ankle has gone through its first sagittal rocker, moving from neutral into planarflexion, which, by moving from supination to pronation, everts the Calcanus and relatively internally rotates everything up the chain.
- Just above, the knee and hip extensors continue to fight gravity in the sagittal plane, as the hip begins moving into Adduction and Internal Rotation. This tri-plane eccentric activation of the hip further activates our gluteals and trunk, as the pelvis is brought into a slight posterior tilt.
- The body has the highest kinetic energy at this moment and this burst of energy and speed lasts until the other limb is lifted, bringing us out of double limb support and imposing the daunting task of climbing that hill of the inverted pendulum during single-leg support.
- Generally, A good take home point is that we’ll see our periods of during double limb support, specifically here during loading response and later during pre-swing, our muscles are primed to fire.
Hip = 20 degrees of flexion
Knee = 15 degrees of flexion
Ankle = 5 degrees of plantarflexion
Gait Assessment
3rd period of the gait cycle?
(3) Mid-Stance
[The 3rd period of gait begins with opposite limb toe off and ends with ipsilateral heel rise]
- Now, once the contralateral leg comes off the ground, we enter our first period of single-leg support during stance. All that work we just witnessed from the quads and glutes has propelled the body over a fixed foot, so that now the ground reaction force is now starting to pass posterior to the hip.
- Here at the top of the hill that is our reverse pendulum, our Center of Mass is at its highest point, maximizing potential energy, so that in a split-second, we will start to fall over the top of our extended leg.
- Muscularly, the chart on your slide doesn’t show it, but we see a lot of activation here from our lateral muscles, Glute Med, Glute Min, and TFL, that work to keep the pelvis level and internally rotate the pelvis using their anterior fibers.
- Collectively, the body passively moving over our fixed leg and the pelvis rotating on by, draws the leg behind us, storing energy in the hip flexors and calf until the calf can stretch no more and starts to pop the heel off the ground.
Hip = 0
Knee = 5 degrees of flexion
Ankle = 5 degrees of dorsiflexion
Gait Assessment
4th period of the gait cycle?
(4) Terminal Stance / Heel-off
[The 4th period of gait begins with ipsilateral heel rise and ends with opposite limb foot contact.]
- Which brings us to terminal stance, where the ankle has just completed its second rocker, moving from plantarflexion in loading response to dorsiflexion throughout single-limb support.
- The supple-movement benefits of a pronated foot during stance are now proving disadvantageous when faced with an imminent toe-off, so with the heel beginning to lift off the ground, the foot follows joint line angles and tension in the calf to begin to plantarflex, regaining the rigidity of supination.
- This now rigid foot allows for the center of pressure that started posterior lateral to finish its migration anterior-medial to the big toe, where the body balances the desire for a long stride with the importance of placing the foot down softly at 0.1 mph… because when the other foot comes down, terminal stance concludes, and our step length is determined.
- Clinically, patient’s really struggle with this period. Here, the pelvis is brought into an anterior tilt as the demands of hip extension and Internal Rotation are maximized. Patients, especially older patients, often lack the requisite hip extension and dorsiflexion this position demands, so they are forced to shorten their stride and adversely load tissues.
Hip = 20 degrees of extension
Knee = 5 degrees of flexion
Ankle = 10 degrees of dorsiflexion
Gait Assessment
5th period of the gait cycle?
(5) Pre-Swing / Toe-off
[The 5th period of gait begins with opposite limb foot contact and ends with ipsilateral toe off]
- Now, once the opposite foot strikes the ground, pre-swing begins. Here, the hip flexors are starting to rocket the leg forward, the knee passively flexes, the tibialis anterior starts to rev up to lift the toes, and the ankle completes its third rocker, moving from dorsiflexion into plantarflexion. The foot is fairly passively plantarflexed in this period until the toe finally leaves the ground, officially bringing us into swing phase.
- Up above, the shoulder girdle (which we have ignored to this point) is rotating equal and opposite to store more rotational energy in the system and reduce energy expenditure by as much as 10%, while the arms swing to dampen rotational forces up the chain, with cervical accelerations being 40% less than lumbar accelerations. This allows us to better keep our head still, while we are out for a daily stroll.
Hip = 10 degrees of extension
Knee = 40 degrees of flexion
Ankle = 15 degrees of plantarflexion
Gait Assessment
6th period of the gait cycle?
(6) Initial Swing
[The 6th period of gait begins with ipsilateral toe off and ends when the medial malleoli are aligned]
- After the toes leave the ground, all the energy generated in pre-swing drives the hip forward into flexion, thereby advancing the leg. Now, swing can get disrupted if the tootsies hit the ground, so we’ll see significant activation of the tibialis anterior during this period to keep the toes from catching the floor.
- We can think of this active dorsiflexion as the fourth rocker of the ankle during gait; however, you typically only hear about the three in weight-bearing. Generally, it’s a tough job, where normal swing only allows a half an inch (1.5cm) of clearance on the best of days, so even slight disruptions of tibialis anterior strength, knee flexion Range of motion, and/or contralateral gluteal strength can disrupt the process.
- Once the medial malleoli are aligned and we have successfully cleared our toes from the ground, we enter the next phase of gait.
Hip = 15 degrees of flexion
Knee = 60 degrees of flexion
Ankle = 5 degrees of plantarflexion
Gait Assessment
7th period of the gait cycle?
(7) Mid-Swing
[The 7th phase of gait begins with the medial malleoli aligned and ends when the ipsilateral tibia is perpendicular to the ground]
- In midswing, it’s all about the knee.
- The toes are cleared, but we’re not ready to put the foot down yet, so all the energy we stored in our knee extensors during passive knee flexion begins to unleash as the knee hinges into extension.
Hip = 25 degrees of flexion
Knee = 25 degrees of flexion
Ankle = 0 degrees
Gait Assessment
8th period of the gait cycle?
(8) Terminal Swing
[The 8th and final phase of gait begins with the tibia perpendicular to the floor and ends when the ipsilateral foot strikes the floor]
- Here in Terminal Swing, the leg reaches its destination, the glues eccentrically activate to slow hip flexion and the hamstrings throw on the breaks to slow the tibia.
- The hip and the knee externally rotate, via activation of the glutes at the hip and the screw home mechanism at the knee. And, as long as the knee can get within 5 degrees of straight, the leg readies itself for another successful heel strike, and the process starts all over again.
Hip = 20 degrees of flexion
Knee = 5 degrees of flexion
Ankle = 0 degrees
Gait Assessment
Initial contact to opposite toe off = ?
purpe
Loading Response:
Gait Assessment
Opposite toe off to heel rise = ?
purpe
Mid-stance:
Gait Assessment
Heel rise to opposite initial contact = ?
purpe
Terminal stance:
Gait Assessment
Opposite initial contact to toe off = ?
purpe
Pre-swing:
Gait Assessment
Toe off to feet adjacent = ?
purpe
Initial swing:
Gait Assessment
Feet adjacent to tibia vertical = ?
Mid-swing:
Gait Assessment
Tibia vertical to initial contact = ?
purpe
Terminal Swing:
Gait Assessment
Describe movement of the:
- Pelvis = ?
- Femur = ?
- Tibia = ?
- Tubtalar joint = ?
- Midfoot = ?
Through the gait cycle.
- Pelvis = Int. rotation, ext. rotation, int. rotation
- Femur = Int. rotation, ext. rotation, int. rotation
- Tibia = Int. rotation, ext. rotation, int. rotation
- Subtalar joint = Everting, inverting, everting
- Midfoot = Increase pliability, increasing stability, increasing pliability
Gait Assessment
Muscular Summary - Weight Acceptance
Muscular Summary - Weight Acceptance:
- With all that said, let’s now turn our attention to the muscular side of things along a functional spectrum. To help read this chart, the boxes are encircling the functional periods we are referencing, and the red bars under the EMG activation chart suggest important muscular activity.
- During the first two phases, initial contact and loading response – our body’s goal is weight acceptance. So, here in the first 10% of gait, we see a host of active muscles.
- As we said earlier, the body co-contracts when it wants stability, and we need to be stable at initial contact. Important muscles include the erector spinae, working to control forward lean of the trunk.
- The glute max is active to fight the hip flexion moment from our ground reaction force.
- Similarly, the gluteus medius and minimus are active to keep the pelvis from dropping excessively into a Trendelenburg pattern.
- The quads and hamstrings are co-contracting to place the foot down gingerly and prove a break to absorb forces.
- The ankle dorsiflexors and toe extensors are screaming to keep the foot from slapping down on the ground.
- While the posterior tibialis ramps up to control the talocrural pronation that’s about to happen and the peroneals get ready to stabilize the forefoot.
Gait Assessment
Muscular Summary - Single-leg Support
Muscular Summary - Single-leg Support:
- Next, the body moves from bilatereal support to single limb support, and consequently the functional demands change.
- Throughout mid-stance and terminal stance, we are functionally in single-leg support. This moment from 10-50% of the gait cycle highlights our hip abductors that (1) fight against contralateral pelvic drop, and (2) begin to use their anterior fibers to advance the pelvis.
- The knee, being relatively straight is quiet in this moment, and down at the foot and ankle, we see contraction of the posterior ankle muscles as they eccentrically control movement of the shin over a fixed foot.
Gait Assessment
Two types of mobility impairments with aging and examples = ?
Impairments:
- General Weakness
- Vestibular
Patient Specific:
- Joint Health / Nerve Health
- Cardiovascular Health
- Vision Loss
Gait Assessment
Gait deviations associated with aging and mobility include = ?
Gait Deviations
- Slower Walking Speed
- Shorter Stride Length
- Less Vertical Displacement of CoM
- Increased Stride Width
- Longer Stance Phase
Gait Assessment
Explain this picture.
- Nearly every portion of your central nervous system plays a role in the control of gait, with gait initiation starting in a top down way, and once we’ve started moving, stead state gait regulated in a bottom up fashion. To illustrate this, let’s use an example of standing, waiting your turn to bowl at a bowling alley.
- Your cortex is in charge of anticipating the need for future motion, and after seeing the person ahead of you bowl a strike, it gives meaning to this mixture of memory and sensation to anticipate your need to go take your turn.
- The basal ganglia then lights up and initiates the mixture of motor signals that allow for postural control and progression.
- The cerebellum aggregates information from sensory centers to orchestrate this postural control while scanning the surrounding for the need to alter your step – like the need to step up to that bowling platform up ahead or moving around those spilled nachos on the floor.
- Working with the cerebellum, your brainstem enhances this postural activation and reciprocal motion, and finally, the central pattern generators in your spinal cord translate stretch signaling into the basics of reflexive and reciprocal movement.
- Any loss of top down control can take away motivation, initiation, orchestration, or signal enhancement, yet even when stripped down to just a spinal cord, your body can perform rudimentary gait.
- So all levels play a role, and in this example, they were successful in getting you to take your first step toward your bowling ball. To do so, all of that good postural anticipation gave feedforward recruitment of your stance leg to activate, so that you can shift your weight off your swing side and take that first step – we see that in the picture on your slide with the foot on the right being unweighted to swing forward. As an example, to see how much anticipation and postural shift play a role in initiation, try placing your stance side shoulder against a wall and step forward with the outside leg.
- The wall keeps you from shifting and makes the whole process feel very awkward, highlighting all the postural anticipation that we tend to take for granted behind the scenes. Now, to this point, all of this is somewhat a review, until we see that little line first going toward the stance leg, then progressing to foot on the left. What’s that little line doing? It’s not a mistake in the drawing.
- This is the first of many iterations of a load signaling what the body should do next. In this case, a posterior shift primes our ankle strategy to activate our dorsiflexors, thereby driving our heel in the ground and priming our hip to shift weight and start to propel the body forward.
Gait Assessment
Stance Phase:
- Functions = ?
- Periods = ?
Stance Phase:
Functions:
- weight acceptance
- single limb support
- swing limb advancement (also part of swing phase)
Periods
- initial contact (weight acceptance)
- loading response (weight acceptance)
- mid-stance (SL support)
- terminal stance (SL support)
- pre-swing (swing limb advancement)
Gait Assessment
Swing Phase:
- Functions = ?
- Periods = ?
Swing Phase:
Functions:
* Swing limb advancement
Periods:
* pre-swing (swing limb advancement)
* initial swing (swing limb advancement)
* mid swing (swing limb advancement)
* terminal swing (swing limb advancement)
Gait Assessment
Describe the periods of gait
- Heel strike (initial contact):
- Loading response (foot flat):
- Midstance:
- Terminal stance:
- Preswing (toe off):
- Initial swing:
- Mid-swing:
- Terminal swing:
- Heel strike (inital contact), pre-swing = two periods of double support
- Heel strike (inital contact) through pre-swing = stance phase (60%)
- Terminal stance (heel off) to end of pre-swing (toe off) = push-off
- Initial swing through terminal swing = swing phase (40%)
