Recovery of Ambulation Post Stroke

Question 1

Gait efficiency

Answer 1

• Distal foot in swing phase is lifted 1-2cm with <4mm step to step variation
• Precision of foot position in swing phase is determined by coordinated activation of LE muscles directly & trunk/arm muscles indirectly
• Combinations of muscle activations that lead to the same foot position is almost infinite (problem of motor redundancy)
• Muscle activities are not controlled individually but in synergies or modules

Question 2

Stroke patients and their gait efficiency

Answer 2

• Stroke survivors with fewer modules on the paretic limb walk more slowly & demo more gait asymmetry
• Gait asymmetry leads to increased energy cost

Question 3

Important information regarding prognosis for recovery of ambulation following stroke

Answer 3

• Static PASS score >3.5 better odds of walking at D/C
• Dynamic PASS score >8.5 better odds of walking at D/C
• 12/56 BBS predictive of regaining unassisted ambulation at D/C
• 29/56 BBS predictive regaining community ambulation speed at D/C
• Discharge = 4 wks of iPR

Question 4

Factors influencing prognosis for recovery of ambulation

Answer 4

• Cognitive impairment & recovery
• Initial walking speed & distance
• Age
• Presence of depressive symptoms
• Self efficacy & motivation
• Stroke severity
• Social support
• Sitting balance
• Hemorrhagic stroke> ischemic stroke
• Most walking recovery will occur in the 1st 11wks after stroke

Question 5

Determinants of walking function following stroke

Answer 5

• Balance is main determinant in pts with more severe gait deficits
• Cardiovascular fitness is main determinant in pts with more mild deficits
• Spasticity does NOT appear to be a major determinant of gait speed

Question 6

Common gait patterns following stroke

Answer 6

• Slow flexed walker
• Slow extended walker (Circumduction)
• Fast walker
• Moderate walker
• Hemiplegic gait

Question 7

Describe a slow flexed walker

Answer 7

• 10% normal gait speed
• Excessive hip/knee flexion in midstance
• Inadequate DF in swing
• Forward trunk lean

Question 8

Describe a slow extended walker/Circumduction

Answer 8

• 11% normal gait speed
• Quads are too weak to support the knee during stance phase
• Glute Max retracts femur into knee hyperextension for stance limb support
• Ankle PF spasticity
• Hip hike & circumduction occur for foot clearance
• Usually require and assistive device (AD)

Question 9

Describe a fast walker

Answer 9

• 44% normal gait speed
• Lack heel rise in terminal stance due to inadequate PF strength
• Knee hyperextension. in stance to compensate for lack of heel rise to allow the body to progress forward on the forefoot
• Compromised step length due to lack of transit of momentum from unaffected side

Question 10

Describe a moderate walker

Answer 10

• 21% normal gait speed
• Increased weakness of PFs
• Weakness in hip extensors (glute Max) & knee extensors (quads)
• Greater knee flexion in midstance

Question 11

Characteristics of hemiplegic gait

Answer 11

• Poor flexor muscle control during swing phase
• Spasticity of extensor muscles lengthening affected leg
• Equinovarus deformity: ankle flexed downward & inward
• Abnormal initial contact along lateral edge of foot & forefoot
• Stiff knee with hyperextension during stance & doesn’t flex during swing
• Contralateral step only meets the paralyzed limb instead of advancing
• Affected leg weight bears for less time
• Rhythmic reciprocal swing of arm with stance phase of opposite leg is absent
• Patient may drag toe of affected leg during swing or compensate another way: contralateral trunk lean or circumduction

Question 12

What are we trying to improve in a post stroke patients gait

Answer 12

• Biomechanics
• Energetics
• Endurance
• Speed
• Independence
• Safety
• Level of physical activity

Question 13

On year after a stroke, _______ of community dwelling individuals with stroke could not complete o 6min walk test (6MWT), and those who could were only able to walk _____ of their predicated normal distance

Answer 13

• One half, 40%

Question 14

Describe how stroke patients have reduced cardiovascular capacity

Answer 14

• Stroke
• Increased energy demands of hemiplegic gait
• Reduced ambulatory activity
• Muscle weakness
• Reduced cardiovascular fitness

Question 15

Average steps per age group (younger adults, older adults, people with disabilities/chronic illnesses, & stroke)

Answer 15

• Healthy younger adults: 7,000-13,000 steps/day
• Healthy older adults: 6,000-8,500 steps/day
• Chronic illness/disabilities: 3,500-5,500 steps/day
• Stroke: average 2,838 steps/day +/- standard deviation

Question 16

Describe ambulatory activity of stroke patients

Answer 16

• Stroke pts ambulatory activity is well below the range of sedentary age-matched adults
• Ambulatory activity level is strongly linked to balance & self selected walking speed
• Increased physiologic workload accompanying balance deficits may indirectly influence the outcome of ambulatory activity

Question 17

Describe the stroke to increased risk of another stroke cycle

Answer 17

• Stroke
• Inpatient rehab (IPR)
• Discharge home
• Inactivity/sedentary behavior
• Reconditioning
• Loss of function & independence
• Detrimental physiologic & psychologic effects of inactivity
• Increased risk for subsequent stroke

Question 18

Cardiovascular considerations for stroke patients

Answer 18

• Immediate rehab following a stroke is primarily focused on recovery of function with limited or absent focus on aerobic fitness
• Patients are encouraged to continue HEP after D/C but most do not
• Stroke patients spend >78% of their time in sedentary behaviors regardless of time since stroke
• Aerobic exercise that matches dosage of cardiac rehab programs improve aerobic capacity for stroke patients regardless of type of activity
• Cardiorespiratory fitness is 50% or normal people same age & sex
• These interventions are still not included in neurorehabilition programs

Question 19

Stroke related outcome measures for entry level DPT students to know

Answer 19

• 6MWT (6 minute walk test)
• 10MWT (10 meter walk test)
• FGA (functional gait assessment)

Question 20

CPG for the use of an AFO and FES post stroke clinical highlights

Answer 20

• AFO custom to the patient is best
• AFO may be better for slow walkers & FES for fast walkers
• AFO/FES combined with PT show more meaningful improvements
• Consistent reassessments needed to meet changing needs
• AFO early in recovery enhances participation & leads to faster progress towards goals
• AFO does not hinder muscle activation
• FES can improve muscle activation (therapeutic effect)
• No evidence that AFO/FES decrease PF spasticity
• AFO that allows PF motion may lead to greater effects on gait speed

Question 21

Define immediate effect

Answer 21

• Testing w/o an AFO/FES followed by re-testing immediately after donning an AFO/FES

Question 22

Define training effect

Answer 22

• Testing with the AFO/FES followed by a period of use with the AFO/FES then re-testing with the AFO/FES

Question 23

Define therapeutic effect

Answer 23

• Testing w/o the AFO/FES followed by a period of use with the AFO/FES then re-testing w/o the AFO/FES

Question 24

Define combined effect

Answer 24

• Cumulative effects of both the immediate and training effects