Flashcards in Gait and Posture Analysis Deck (104):
What are the 2 main functions of the lower kinetic chain?
- To provide a stable BOS in standing
- To propel the body through space with gait
What can be defined as controlled instability?
What are the 3 essential requirements of gait?
- Postural control
What can be defined as the interval of time between any of the repetitive events of walking?
the gait cycle
What are the 2 phases of gait?
Stance and swing
What percentage of the gait cycle consists of the stance phase? Swing phase?
What are the 3 tasks of the gait cycle?
- weight acceptance
- single limb support
- limb advancement
What does weight acceptance include?
the intervals of initial contact and loading response
Initial contact interval accounts for the first __% of the gait cycle
What does single-leg support include?
midstance, terminal stance, and preswing
It is the time in which one foot is being lifted until the body weight is aligned over the forefoot
*the first half of the single-limb support task
When does the terminal stance begin and end?
Begins when the heel of the weight-bearing foot lifts off the ground and continues until the contralateral foot strikes the ground
When does preswing begin and end?
Begins with initial contact of the contralateral limb and ends with the ipsilateral toe-off
What does the swing phase involve?
the forward motion of the NWB foot
What are the 3 intervals during the swing phase?
- Initial swing
- Terminal swing
When does initial swing begin and end?
Begins with the lifting of the foot from the floor and ends when the swinging foot is opposite the stance foot
When does midswing begin and end?
Begins as the swinging limb is opposite the stance limb and ends when the swinging limb is forward and the tibia is vertical
When does terminal swing begin and end?
Begins with a vertical tibia of the swing leg with respect to the floor and ends the moment the foot strikes the floor
What is normal step width and what does it form?
Normal is 5-10cm (2-4”) and it forms the BOS
What can be defined as the distance between the point of initial contact of one foot and the point of initial contact of the opposite foot?
What is average step length?
What can be defined as the distance between successive points of foot to floor contact of the same foot?
What makes up a stride length?
2 step lengths added together (56")
What is the normal cadence of gait?
90-120 steps per minute
During gait, the vertical ground reaction force is created by what?
a combination of gravity, body weight, and the firmness of the ground
When do the 2 peaks during the gait cycle occur?
- 1st at maximum limb loading during the loading response
- 2nd during terminal stance
Do men or women tend to experience greater cumulative ground reaction forces? Explain why...
Women, because their legs account for a smaller percentage of total body height which means they must strike the ground more often to cover the same distance
What does gait involve?
The displacement of body weight in a desired direction
What are the 5 priorities of normal gait?
- Stability of the weight bearing foot throughout the stance phase
- Clearance of the NWB foot during the swing phase
- Appropriate prepositioning of the foot during terminal swing for the next gait cycle
- Adequate step length
- Energy conservation
In order for gait to be efficient and to conserve energy what must/must not occur?
the COG must undergo minimal displacement
What are the 6 determinants have the potential to reduce the energetic cost of human gait?
- Lateral displacement of the pelvis
- Pelvic rotation
- Vertical displacement of the pelvis
- Knee flexion in stance
- Ankle mechanism
- Foot mechanism
What is normal lateral displacement of the hips?
1-2” in order to center body weight over the stance leg
What does the forward rotation of the pelvis on the swing side prevent?
an excessive drop in the body’s COG
What does the vertical displacement of the pelvis do?
Keeps the COG from moving superiorly and inferiorly more than 2” during normal gait
If there is a disruption in the vertical displacement of the pelvis, what occurs?
What does knee flexion during midstance prevent?
an excessive rise in the body’s COG during that period of the gait cycle
Normal gait requires __ degrees of DF & __ degrees of PF
Describe the ankle mechanism present during gait
The co-action of dorsiflexion and plantarflexion muscles produces a relative lengthening of the leg, which results in a smoothing of the COG during stance phase
Describe the foot mechanism present during gait
The controlled lever arm of the forefoot at preswing is helpful as it rounds out the sharp downward reversal of the COG
As the upper body moves forward, the trunk twists about a ____ axis
As the upper body moves forward, the thoracic spine and pelvis rotate in ____ directions
As the upper body moves forward, the lumbar spine tends to rotate with the ____.
As the upper body moves forward, the shoulders and trunk rotate __________.
out of phase with each other
When arm swing is prevented during gait, what occurs?
the upper trunk tends to rotate in the same direction as the pelvis, producing an awkward gait
What are the functions of the hip during gait?
to extend the leg during stance phase and flex the leg during swing phase
The hip rotates approximately __-__ degrees during normal stride
There is __-__ degrees of hip flexion in late swing
There is __ degrees of hip extension at or near toe off
Describe when hip adduction and abduction occur during gait
Hip adduction occurs in early swing phase
Slight hip abduction at the end of swing phase
When does the greatest force on the hip occur?
The knee flexes to __ degrees during the loading response of gait
How many degrees of knee motion is required for adequate foot clearance during normal gait?
_____ gliding of the femoral condyles “unlocks” the knee during the loading response
What controls forward gliding at the knee during gait?
passive restraint of the PCL and actively by the quadriceps
What are the 4 functions of the knee during gait?
- Bear weight and absorb shock
- Reduce vertical displacement of the COG
- Maintain the stride length
- Allow the foot to move through its swing
Describe the position of the ankle joint during initial contact
The heel is slightly inverted, and the subtalar joint is slightly supinated
During the loading response, ______ occurs at the talocrural joint and _____ occurs at the Subtalar joint
What is the significance of pronation at the subtalar joint during the loading phase?
It unlocks the foot and allows maximal ROM of the midtarsal joint, which enhances the foot’s ability to adapt to the support surface
At the end of midstance the talocrural joint is maximally ______ and the subtalar joint begins to _____.
From midstance to terminal stance is the foot in pronation or supination
How should you observe a patient's gait?
Barefoot and with footwear
Toe walking and heel walking
When examining a patient's footwear where should you findthe greatest wear?
- Beneath the ball of the foot
- In the area corresponding to the first, second and third MTP joints
- To the lateral side of the heel
What formation can also indicate gait dysfunction?
A weakness in gait indicates what 2 things?
- There is inadequate internal joint movement
- There is a loss of the natural force-couple relationship
Neuromuscular conditions include what 3 abnormal gait characteristics?
- Abnormalities of muscle tone
- Timing of muscle contractions
- Proprioceptive and sensory disturbances
What are the 2 things that can cause abnormal joint position?
- imbalance of flexibility and strength
When are elastic contractures apparent during gait?
in the swing phase
When are rigid contractures apparent during gait?
during the swing and stance phases
What are a few things that can cause antalgic gait?
- Bone disease (fracture, infection, tumor or AVN)
- Muscle disorder (rupture, contusion, cramp, spasm)
- Joint disease (OA, RA, gout, bursitis, hemarthrosis)
- Neurologic disease (lumbar spine disease with nerve root involvement)
- Hip, knee or foot trauma
- Corns, bunions, blisters or ingrown toenails
Describe Equinus Gait
The forefoot strikes first to initiate the gait cycle.
There is premature plantarflexion in early midstance.
Increased flexion at the knees in stance phase.
Delayed or diminished knee flexion in swing phase.
Diminished hip extension.
Increased anterior pelvic tilt.
Describe Gluteus Maximus Gait
Posterior thrusting of the trunk at initial contact in an attempt to maintain hip extension of the stance leg
Anterior tilt of the pelvis causes hyperlordosis
What is gluteus maximus gait due to?
weak hip extensors
How do people with weak quadriceps tend to compensate?
The affected LE is circumducted and the patient leans toward the uninvolved side to balance the COG
People with weak quadriceps tend have difficulty walking on what types of surfaces?
rough or uneven surfaces
What is steppage gait due to?
Describe steppage gait
There is increased hip and knee flexion to compensate for decreased dorsiflexion and the foot tends to make an audible slap on the floor
What is Trendelenburg Gaitdue to?
weakness of the hip abductors
What is plantar flexor gait due to?
Premature firing of the gastroc during the swing phase
What is plantar flexor gait characterized by?
plantar flexor gait is a common deviation in what type of patient?
children with CP
What causes spastic hemiplegic gait?
Unilateral UMN lesion
Describe spastic hemiplegic gait
The LE circumducts and the UE is carried across the trunk for balance
What causes spastic paraparetic gait?
Bilateral UMN lesions
Describe spastic paraparetic gait
Slow, stiff and jerky movements
Spastic extension occurs at the knees
Adduction at the hips causing "scissors gait"
Describe ataxic gait
Walking is characterized by a widened base, high stepping, staggering or lurching from side to side
What is the difference bewteen cerebellar and sensory gait?
Cerebellar: broad based, unsteady and staggering with an irregular sway
Sensory: patient tends to lift the feet too high and slap on the floor in an uncoordinated manner
Describe the gait deviations present following TKA
- Slower cadence
- Shorter step length
- Reduced knee excursion
- Altered muscle activation
- Stiff-knee posture
Describe the gait deviations present following THA (anterolateral approach)
- Greater trunk forward lean
- Trendelenburg gait
Describe the gait deviations present following THA (posterolateral approach)
- Greater incidence of dislocation
What are the 3 indications for using an AD?
- Decreased ability to bear weight through the LEs
- Muscle weakness or paralysis or the trunk or LEs
- Decreased balance and proprioception in the upright posture
What can be defined as “the optimal alignment of the patient’s body that allows the neuromuscular system to perform actions requiring the least amount of energy to achieve the desired effect”
Where should the COG fall?
As the neuromuscular system declines what types of changes tend to occur?
- Increased lumbar lordosis
- Increased thoracic kyphosis
- Decreased hip extension
- Decreased medial-lateral stability
- Increased hip flexed posture
- Decreased stride length
- Greater weight placed on the forefoot
- Increased double-foot stance time
- Decreased proprioception
- Harder heel strike
What are 3 gait chances that occur with age?
- A transition from ankle strategy back to hip strategy during gait
- A broadened stance to combat increased med-lat instability
- A shortened stride length to better maintain COG
Describe ideal postural alignment
A straight line that passes through:
- The ear lobe
- The bodies of the cervical vertebrae
- The tip of the shoulder
- Midway through the thorax
- Through the bodies of the lumbar vertebrae
- Slightly posterior to the hip joint
- Slightly anterior to the axis of the knee joint
- Slightly anterior to the lateral malleolus
Lordotic posture causes what 3 muscle impairments?
- Decreased mobility in the hip flexors
- Decreased mobility in the lumbar extensors
- Stretched and weak abdominal muscles
Slouched posture causes decreased mobility in what muscles?
- upper abdominal muscles
- internal intercostals
- hip extensors
- lower lumbar extensors
Slouched posture causes which muscles to become stretched and weakened?
- lower abdominals
- distal thoracic extensors
- hip flexors
Flat back posture causes decreased mobility in what muscles?
trunk flexors and hip extensors
Flat back posture causes which muscles to become stretched and weakened?
lumbar extensors and hip flexors
Round back posture with forward head causes decreased mobility in what muscles?
- anterior thorax muscles (intercostals)
- muscles of the UE originating on the thorax (pecs, lats and serratus)
- muscles of the cervical spine and head that attach to the scapulae and upper thorax (levator, SCM, scalenes, upper traps)
- suboccipital muscles (rectus capitis post major and minor, Obliquus capitis inf and sup)
Round back posture with forward head causes which muscles to become stretched and weakened?
- lower cervical and upper thoracic erector spinae
- scapular retractor muscles (rhomboids and middle traps)
- anterior throat muscles
- capital flexors
What is the purpose of gait interventions?
to alleviate symptoms and educate the patient in correct posture