This thesis has provided an understanding of the effects of a single session of CKC and OKC exercises emphasizing speed on the muscle activation patterns of individuals in the sub-acute phase post-stroke. The exercises evoked improvements in the paretic muscles by the end of the squats and steps (Chapter 3) and in the single joint OKC exercises of the knee and the ankle (Chapter 5). However, knowing that changes can be generated does not provide information on the mechanisms underlying the effect. For instance, if the changes are induced at the cortical level, it is possible that a short program of 3-4 weeks might be appropriate for these types of exercises. Perez et al28 reported increased cortical excitability in the motor cortex area of the tibialis anterior when healthy individuals
performed a motor learning task comprised of voluntary ankle movements for 32 minutes. Thus, one of the next steps would be to determine the appropriate length of an exercise program that would be needed to evoke long-term changes.
There is some evidence that the improvements observed in the muscle activation patterns in the exercises transferred to a postural task that was not practiced. This is a good
indication that changes with exercises emphasizing speed may be adaptable to other activities. It has been shown that strength training does not necessarily transfer to functional activities unless it is task specific29,30 therefore, it is important to understand what type of exercises can modify functional activities without being task specific. The final step would be to determine if the changes observed in the exercises can be
transferred to improvements in functional activities.
6.6
Conclusion
This thesis revealed there are impairments in the muscle activation patterns in fast movements performed by individuals post-stroke. These impairments can be modified with CKC and OKC exercises emphasizing speed in individuals with mild to moderately- severe stroke. The changes observed in the muscle activation patterns during the fast CKC and OKC exercises transferred to postural control tasks that were not practiced. This thesis demonstrates the efficacy of movements emphasizing speed on improving motor control post-stroke. Further research is needed to determine the length of program necessary to evoke long-term changes and if the changes can be transferred to functional activities.
6.7
References
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Appendix A: Characteristics of stroke group (Chapter 2, 3 and 4).
Subject Age (years) CMSA leg+foot ( /14) Berg Balance Scale ( /56) Gender Side ofParesis Location of stroke
*1 37 10 54 M Right unknown *2 67 9 44 F Left subcortical *3 47 14 56 F Left subcortical *4 51 6 40 M Left subcortical *5 72 12 56 M Left cortical *6 80 11 49 M Left cortical *7 67 13 49 M Left cortical *8 52 12 42 M Left subcortical/cortical *9 66 12 54 M Left cortical *10 48 8 56 F Right subcortical/cortical *11 66 12 47 F Left subcortical *12 65 8 49 F Left subcortical *13 47 13 56 M Right subcortical *14 63 14 56 M Right subcortical *15 50 9 55 M Right subcortical/cortical *16 53 13 56 M Left subcortical *17 27 7 53 F right subcortical 18 55 13 56 F right cortical 19 59 9 54 M left subcortical 20 53 5 46 M left unknown 21 74 11 54 M left subcortical 22 56 12 48 M left subcortical 23 76 12 56 M left subcortical 24 35 8 53 M left unknown 25 53 7 55 M left cortical 26 58 12 55 M left cortical 27 49 14 56 M right subcortical 28 59 11 49 M left unknown 29 31 10 55 F left subcortical 30 41 14 56 M right subcortical 31 45 8 50 F left subcortical/cortical 32 78 8 54 F left subcortical
Location of stroke determine by CT or MRI *Subjects for Chapter 2
Appendix B: Clinical Outcome Measures
Berg Balance Scale
SITTING TO STANDINGINSTRUCTIONS: Please stand up. Try not to use your hand for support. ( ) 4 able to stand without using hands and stabilize independently ( ) 3 able to stand independently using hands
( ) 2 able to stand using hands after several tries ( ) 1 needs minimal aid to stand or stabilize ( ) 0 needs moderate or maximal assist to stand STANDING UNSUPPORTED
INSTRUCTIONS: Please stand for two minutes without holding on. ( ) 4 able to stand safely for 2 minutes
( ) 3 able to stand 2 minutes with supervision ( ) 2 able to stand 30 seconds unsupported
( ) 1 needs several tries to stand 30 seconds unsupported ( ) 0 unable to stand 30 seconds unsupported
If a subject is able to stand 2 minutes unsupported, score full points for sitting unsupported. Proceed to item #4.
SITTING WITH BACK UNSUPPORTED BUT FEET SUPPORTED ON FLOOR OR ON A STOOL INSTRUCTIONS: Please sit with arms folded for 2 minutes.
( ) 4 able to sit safely and securely for 2 minutes ( ) 3 able to sit 2 minutes under supervision ( ) 2 able to able to sit 30 seconds
( ) 1 able to sit 10 seconds
( ) 0 unable to sit without support 10 seconds STANDING TO SITTING
INSTRUCTIONS: Please sit down. ( ) 4 sits safely with minimal use of hands ( ) 3 controls descent by using hands
( ) 2 uses back of legs against chair to control descent ( ) 1 sits independently but has uncontrolled descent ( ) 0 needs assist to sit
TRANSFERS
INSTRUCTIONS: Arrange chair(s) for pivot transfer. Ask subject to transfer one way toward a seat with armrests and one way
toward a seat without armrests. You may use two chairs (one with and one without armrests) or a bed and a chair.
( ) 4 able to transfer safely with minor use of hands ( ) 3 able to transfer safely definite need of hands ( ) 2 able to transfer with verbal cuing and/or supervision ( ) 1 needs one person to assist
( ) 0 needs two people to assist or supervise to be safe STANDING UNSUPPORTED WITH EYES CLOSED
INSTRUCTIONS: Please close your eyes and stand still for 10 seconds. ( ) 4 able to stand 10 seconds safely
( ) 3 able to stand 10 seconds with supervision ( ) 2 able to stand 3 seconds
( ) 1 unable to keep eyes closed 3 seconds but stays safely ( ) 0 needs help to keep from falling
STANDING UNSUPPORTED WITH FEET TOGETHER
INSTRUCTIONS: Place your feet together and stand without holding on. ( ) 4 able to place feet together independently and stand 1 minute safely
( ) 3 able to place feet together independently and stand 1 minute with supervision ( ) 2 able to place feet together independently but unable to hold for 30 seconds ( ) 1 needs help to attain position but able to stand 15 seconds feet together ( ) 0 needs help to attain position and unable to hold for 15 seconds
REACHING FORWARD WITH OUTSTRETCHED ARM WHILE STANDING
INSTRUCTIONS: Lift arm to 90 degrees. Stretch out your fingers and reach forward as far as you can. (Examiner places a ruler at
the end of fingertips when arm is at 90 degrees. Fingers should not touch the ruler while reaching forward. The recorded measure is
the distance forward that the fingers reach while the subject is in the most forward lean position. When possible, ask subject to use
both arms when reaching to avoid rotation of the trunk.) ( ) 4 can reach forward confidently 25 cm (10 inches) ( ) 3 can reach forward 12 cm (5 inches)
( ) 2 can reach forward 5 cm (2 inches) ( ) 1 reaches forward but needs supervision
( ) 0 loses balance while trying/requires external support
PICK UP OBJECT FROM THE FLOOR FROM A STANDING POSITION INSTRUCTIONS: Pick up the shoe/slipper, which is in front of your feet. ( ) 4 able to pick up slipper safely and easily
( ) 3 able to pick up slipper but needs supervision
( ) 2 unable to pick up but reaches 2-5 cm(1-2 inches) from slipper and keeps balance independently
( ) 1 unable to pick up and needs supervision while trying
( ) 0 unable to try/needs assist to keep from losing balance or falling
TURNING TO LOOK BEHIND OVER LEFT AND RIGHT SHOULDERS WHILE STANDING INSTRUCTIONS: Turn to look directly behind you over toward the left shoulder. Repeat to the right. (Examiner may pick an object
to look at directly behind the subject to encourage a better twist turn.) ( ) 4 looks behind from both sides and weight shifts well
( ) 3 looks behind one side only other side shows less weight shift ( ) 2 turns sideways only but maintains balance
( ) 1 needs supervision when turning
( ) 0 needs assist to keep from losing balance or falling TURN 360 DEGREES
INSTRUCTIONS: Turn completely around in a full circle. Pause. Then turn a full circle in the other direction.
( ) 4 able to turn 360 degrees safely in 4 seconds or less
( ) 3 able to turn 360 degrees safely one side only 4 seconds or less ( ) 2 able to turn 360 degrees safely but slowly
( ) 1 needs close supervision or verbal cuing ( ) 0 needs assistance while turning
PLACE ALTERNATE FOOT ON STEP OR STOOL WHILE STANDING UNSUPPORTED INSTRUCTIONS: Place each foot alternately on the step/stool. Continue until each foot has touched the step/stool four times.
( ) 4 able to stand independently and safely and complete 8 steps in 20 seconds ( ) 3 able to stand independently and complete 8 steps in > 20 seconds
( ) 1 able to complete > 2 steps needs minimal assist ( ) 0 needs assistance to keep from falling/unable to try STANDING UNSUPPORTED ONE FOOT IN FRONT
INSTRUCTIONS: (DEMONSTRATE TO SUBJECT) Place one foot directly in front of the other. If you feel that you cannot place
your foot directly in front, try to step far enough ahead that the heel of your forward foot is ahead of the toes of the other foot. (To
score 3 points, the length of the step should exceed the length of the other foot and the width of the stance should approximate the
subject’s normal stride width.)
( ) 4 able to place foot tandem independently and hold 30 seconds ( ) 3 able to place foot ahead independently and hold 30 seconds ( ) 2 able to take small step independently and hold 30 seconds ( ) 1 needs help to step but can hold 15 seconds
( ) 0 loses balance while stepping or standing STANDING ON ONE LEG
INSTRUCTIONS: Stand on one leg as long as you can without holding on. ( ) 4 able to lift leg independently and hold > 10 seconds
( ) 3 able to lift leg independently and hold 5-10 seconds ( ) 2 able to lift leg independently and hold L 3 seconds
( ) 1 tries to lift leg unable to hold 3 seconds but remains standing independently. ( ) 0 unable to try of needs assist to prevent fall
THE CHEDOKE McMASTER STROKE ASSESSMENT
Revised October 2004
Standard starting position: Lying on back with knees bent and feet flat, with hands resting on stomach, shoes and socks off, and pants rolled up. Start assessment at Stage 4.
STAGE 1
Unable to demonstrate at least two of the Stage 2 tasks.
STAGE 2
Task 1: Resistance to passive hip or knee flexion
Position: Standard starting position, with limb supported as necessary. Instruction: "Let me move your leg."
Method: Choose either a) or b):
a) flex and extend hip 5 times with sufficient speed of passive movement to elicit stretch reflex. Feel for resistance to passive movement and watch for an active contraction of quadriceps.
b) flex and extend knee 5 times with sufficient speed of passive movement to elicit stretch reflex. Feel for resistance to passive movement and watch for an active contraction of the quadriceps.
Task 2: Facilitated hip flexion
Position: Standard starting position.
Instruction: "Bend your leg towards your chest." Method: Facilitate a contraction of the hip flexors. Required: Some active hip flexion.
Task 3: Facilitated extension
Position: Standard starting position. Instruction: "Straighten your leg out."
Method: Facilitate a contraction of hip and knee extensors. Required: Some active contraction of hip or knee extensors.
STAGE 3
Task 1: Adduction to neutral
Position: Standard starting position with weak leg abducted. Instruction: "Bring your weak knee into the middle."
Task 2: Hip flexion to 90 degrees
Position: Standard starting position.
Instruction: "Bend your leg up towards your chest."
Required: Hip flexion to 90° (hip adduction or pelvic tilt are permitted).
Task 3: Full extension
Position: Standard starting position. Leg may be stabilized. Instruction: "Straighten your leg out."
Method: Full active hip and knee extension. Gravity may assist with the movement but do not use a non-slip material under the weak foot. Adduction and internal rotation are not required, but are permitted.
STAGE 4
Task 1: Hip flexion to 90 degrees then extension synergy
Position: Standard starting position. The unaffected leg remains in flexion during this task.
Instruction: "Bend your leg up towards your chest, and out to the side. Then without stopping, straighten your leg out, crossing your weak leg over the mid- line."
Required: Hip and knee flexion to 90°, hip abduction to 45°, and external rotation at least to neutral during the flexion component. Full hip extension, internal rotation and adduction sufficient to cross the weak foot over mid-line. No stopping between synergies.
Task 2: Bridging hips with equal weight bearing
Position: Standard starting position.
Instruction: "Lift your hips off the bed pushing equally with both feet.”
Method: Test for equal weight bearing by trying to displace the weak foot. Don't use a non-slip material under weak foot.
Required: Hip extension and weight bearing equal bilaterally. Pelvis aligned.
Task 3: Knee flexion beyond 100 degrees
Position: Sitting, hips and knees flexed to 90° and feet supported. Instruction: "Bend your knee back as far as you can."
Required: Knee flexion greater than 100o.
Acceptable: Part of the foot can remain in contact with the floor. Don't accept: Excessive trunk movement.
Position: Standard starting position. The unaffected leg remains in flexion during this task.
Instruction: "Straighten your leg out crossing your weak leg over the mid-line, then without stopping, bring your weak leg up to your chest and out to the side."
Required: Full extension of hip and knee with sufficient hip internal rotation and adduction to cross weak foot over the mid-line. Hip and knee flexion to 90˚, hip abduction to 45˚ with external rotation at least to neutral. Smooth transition between synergies.
Task 2: Raise thigh off bed
Position: Sitting, hips and knees flexed to 90˚. Feet on floor. Instruction: "Lift your thigh off the bed."
Required: Active hip flexion through inner range so that the thigh clears the bed. Don't accept: External rotation of hip, compensating trunk movements, or use of hands.
Task 3: Hip extension with knee flexion
Position: Standing on strong leg with support.
Instruction: "Take your leg back, keep it there, then bend your knee up." Method: Therapist may provide light support for balance.
Required: Hip extension to 0˚ with enough knee flexion to raise the foot off the floor. Don't accept: Compensatory trunk movements or weight bearing through the support
offered by the therapist. Less than neutral hip extension while flexing knee.
STAGE 6
Task 1: Lift foot of floor 5 times in 5 seconds
Position: Sitting with hip and knees at 90°, feet supported.
Instruction: “Lift your thigh off the bed and stamp the floor with your whole foot 5 times.”
Method: Count the number of times the foot taps the floor in 5 seconds. Required: 90˚knee flexion. Each repetition should be of equal amplitude. Don't accept: Compensatory trunk or hip movements, less than 90˚knee flexion.
Task 2: Full range internal rotation
Position: Sitting with hip and knees at 90o, feet supported.
Instruction: "Keep your knees together and spread your ankles apart.” Method: It is permissible to hold on to the bed.
Required: Full range of internal rotation (compare to other side), no compensatory trunk movements. Feet should come off the support.
Task 3: Trace a pattern: forward, side, back, return