Transcript Higher Efficacy of Modified Constraint Induced Movement
Higher Efficacy of
Modified Constraint Induced Movement Therapy
versus
Conventional Rehabilitation Therapy
in Acute Stroke Patients
•
Annually
, there are approximately
15 million
people worldwide suffering from cerebrovascular stroke. • Of these,
5 million
are permanently disabled • • Thus stroke represents
one
of the leading causes of disability among all CNS disorders .
One
of the disabling consequences of cerebrovascular stroke is functional impairment of the affected upper extremity since its recovery is often delayed than that of the lower extremity .
Rehabilitation Options For Individuals With Acute Stroke
• • • Most rehabilitation strategies of acute hemiplegic patients focus on compensation rather than restoration of upper extremity function since patients use the unaffected upper extremity for activities of daily living. Recently, new treatment strategies were introduced that might be more effective than conventional rehabilitation treatment. Promising approaches include practice with robotic devices or use of a virtual environment with electrical stimulation to increase cortical excitability during training. One potential method to improve sensorimotor recovery after acute stroke is constraint induced movement therapy (CIMT) , often labeled efficiency of CIMT protocols. “forced use” treatment which is a currently popular therapy with a sound theoretical foundation. Many reports are available about its effectiveness on cortical reorganization and there is mounting evidence for the
• CIMT is a behavioural approach in neurorehabilitation based on the principle of ‘learned non-use’. The term is derived from studies of non-human primates in which somatosensory deafferentation of a single forelimb was performed, after which the animal failed to use that limb. The major components of CIMT include: intense, repetitive (task oriented) training and behavioral shaping of the impaired limb with immobilization of the unimpaired arm. Intensive CIMT involves constraint of the unaffected arm for at least 90% of the waking hours whilst modified CIMT (m-CIMT) consists of constraint of the unaffected arm with a padded mitt or arm sling for a minimum of 6 hours per day .
• In contrast to conventional therapy in acute stroke, CIMT discourages the use of the unaffected extremity and encourages the active use of the hemiplegic arm in order to restore the motor function
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. CIMT can be thought to exert an indirect effect on the paretic limb use by preventing compensatory use of the less-affected limb for some tasks. On the other hand, the task-specific training with the paretic limb can be thought to exert a direct effect on paretic limb use. There are numerous studies that have suggested that CIMT can lead to considerable improvement in hand function which lasts for more than a year after training
.
identification of the patient potentials for motor recovery is important in order to avoid “
learned disuse ’’
and to be able to initiate appropriate therapy with realistic goals Recovery is due to brain plasticity which occurs through cortical reorganization. Three major
mechanisms
for this plastic reorganization:
1.
unmasking
pathways, of existing but functionally inactive
2.
3.
sprouting
formation of circuits allowing alternative pathways to take over functions of fibers from surviving neurons and
new
synapses and redundancy of CNS
• An essential question is "Does modified constraint induced movement therapy has higher efficacy than conventional rehabilitation therapy in management of acute stroke patients?".Consequently , in this article, the authors assessed functionally and neurophysiologically the efficacy of modified constraint induced movement therapy on functional recovery of upper extremity (UE) in acute stroke patients, as compared to conventional therapy with the same total rehabilitation peroid. .
Objective
To assess the efficacy of modified CIMT on functional recovery of upper extremity (UE) in acute stroke patients, as compared to conventional rehabilitation therapy
Methodology
• This study included twenty six acute stroke patients. • Inclusion criteria included the following: patients within two weeks from the onset of stroke, persistent hemiparesis leading to impaired upper extremity function, evidence of preserved cognitive function and a minimum of 10 degrees of active finger extension and 20 degrees of active wrist extension.
• Exclusion criteria
included the following: intracerebral hemorrhage, previous stroke on the same side, presence of neglect or a degree of aphasia impeding understanding of instructions and patients with conditions that limit the use of the upper limb before the stroke. • .
• The patients were divided into two groups.
• Group A
: 13 patients were given a
conventional
rehabilitation program for two weeks. • Group B : 13 patients were subjected to the modified CIMT for two consecutive weeks. Total treatment time was kept identical in both groups
• Patients were
assessed
by Brunstrom Fugl Meyer test Motor Assessment test (
FMA
), Action Research Arm Test (
ARAT
) and Motor evoked potentials (
MEPs)
recorded from the abductor pollicis brevis of the affected hand. The clinical and neurophysiological tests were performed pre and post rehabilitation
FMA upper extremity motor section of Brunstrom-Fugl Meyer Assessment (FMA) to evaluate motor performance and function of the upper extremity where 0= cannot perform and 2= can perform fully
It includes: Reflex activity , flexor synery, extensor synergy, combining synergies, out of synergy, wrist, hand, coordination
ARAT
): quantitative test for the upper extremity function. There are four subsets:
Grasp, Grip, Pinch and Gross
movement
.
Items in each are ordered in such a way that if the patient performed the most difficult item (the first item of each subscale), then this predicts success with all less difficult subscale items. Thus, the patient is scored with the maximum score for that subscale for that limb. On the other hand, failure with the easiest item (the second item of the first three subscales and the first item of the fourth subscale) predicts failure with all items of greater difficulty on that subscale and the patient is scored zero and again no more tests needed to be performed in that subset. Otherwise the patient needs to complete all tasks within the subset
.
Materials needed to perform the test:
Wood blocks, a ball, a stone, two different sizes of alloy tubes, a washer and bolt, two glasses, a marble and a 6-mm ball bearing.
Scoring :
The test is a four point scale ranging from 0 to 3 with maximum score =57.
0= Can perform no part of the test.
1= Perform test partially.
2= Complete test but takes abnormally long time or has great difficulty.
3= Perform test normally.
Items of the Action Research Arm Test.
• 1-
Grasp
subscale.
Grasp and lift blocks, a ball and a stone from one shelf of a table to another.
i – Pick up a block wood of 10 cm diameter (if score =3, total = 18 and go to grip).
ii – Pick up a block wood of 2.5 cm diameter ( if score =0, total =0 and go to grip).
Iii – Pick up a block wood of 5 cm diameter.
iv – Pick up a block wood of 7.5 cm diameter.
v – Pick up a ball of 7.5 cm diameter.
vi – Pick up a stone 10X2.5X1 cm.
• 2-
Grip
subscale.
• i– Pour water from glass to another (if score =3, total=12 and go to pinch).
• ii– Displace an alloy tube (diameter 2.5 cm) from one side of the table to the other (if score = 0, total =0 and go to pinch).
• iii– Displace an alloy tube (diameter 1 cm) from one side of the table to the other.
• iv– Put washer over a bolt.
• 3-
Pinch
subscale.
• Pinch and lift the ball and block from one shelf of a table to another (lift over 37 cm).
• i– Ball bearing of 6mm diameter between 3rd finger and thumb (if score =3, total = 18 and go to gross movement).
• ii– Marble bearing of 1.5 cm diameter between first finger and thumb (if score = 0, total = 0 and go to gross movement).
• iii– Ball bearing between 2nd finger and thumb.
• iv– Ball bearing between 1st finger and thumb.
• v– Marble bearing between 3rd finger and thumb.
• vi– Marble bearing between 2nd finger and thumb.
• 4-
Gross
movement subscale.
• i– Place hand behind head (If score =3, total=9 and finish), (If score = 0, total = 0 and finish).
• ii– Place hand on top of head.
• iii– Hand to mouth.
Neurophysiological evaluation
• • • • • Transcranial magnetic stimulation (TMS) was used as a diagnostic tool for estimation of resting motor threshold (RMT), motor evoked potential (MEPs) amplitude, central motor conduction time (CMCT)). TMS was performed initially and repeated after completion of the rehabilitation program. The clinical neurophysiologist was masked to the results of the clinical assessments.
A Dantec keypoint EMG was utilized to collect the signal. Maglit Model 200 stimulator with 90 mm a figure of 8 coil. Stimuli were given on the infarcted side. Coil placement was performed as described by Malcolm et al.
latency were obtained. The stimulus intensity was increased to the maximum before a response was considered absent.
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Motor response was recorded by surface electrodes placed over contralateral abductor pollicis brevis (APB). After recording RMT, the stimulus intensity was increased until potentials with the largest amplitude and shortest
Resting motor threshold
produce motor evoked potential> 50 uV in at least 5 out of 10 consecutive stimulations.
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was defined as the lowest intensity necessary to
The motor evoked potential amplitude
was determined as peak to peak amplitude (mV). MEPs were considered absent if no response could be obtained with 4 stimulations at maximum intensity.
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CMCT
was calculated as the latency difference between responses to stimulation of the motor cortex (TMCT) and the cervical ventral roots (peripheral latency).
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Schematic representation of the calculation of CMCT.
A- Motor evoked potential induced by TMS, TMCT is calculated (T1).
B- MEP after cervical spinal root stimulation, peripheral latency is calculated (T2).
CMCT= T1-T2
• Recording : from the abductor pollicis brevis muscle by surface electrodes using Dantec keypoint EMG apparatus.
• •
Resting motor threshold
• MEP
amplitude
: is defined as the lowest stimulus intensity evoking a MEP> 50 uv recorded from thenar muscle after magnetic stimulation of the motor cortex. : peak to peak amplitude (mV).
CMCT
: latency difference between responses to stimulation of the motor cortex (TMCT) and the ventral roots (peripheral latency).i.e. subtracting peripheral latency from TMCT MEPs were considered absent if no response could be obtained with 4 stimulations at 100% intensity.
III)
Medical
treatment according to the guidelines of the Ain Shams University stroke group.
IV) Rehabilitation program Group A, the patients were subjected to a standard conventional one to one rehabilitation program for two hours per day, 5 days per week for 2 consecutive weeks. The prescription of the program was tailored according to each patient ’s clinical and functional assessment and modified according to the development of his condition. It included traditional positioning, management of spasticity, standard occupational therapy, compensatory techniques in activities of daily living (ADL), strengthening exercises and range of motion exercises..
•
Group B,
the patients were subjected to CIMT. CIMT consisted of 2 main elements; movement restriction and shaping: Restriction of movement of the unaffected extremity was achieved by asking the patient to wear a mitten on the unaffected hand for at least 6 hours per day during the 2 week treatment period. Onsite training of the affected arm was done in the rehabilitation outpatient department by a procedure termed "shaping" for two hours per day, 5 days per week for 2 consecutive weeks. Shaping (adapted task practice) is a method in which motor task difficulty is adjusted in small steps to the patient motor capabilities. Shaping was carried out for various tasks related to (ADL) and routine home activities. Task objects frequently used were children building blocks, marbles) . A formal behavioral contract with the patient was set up detailing the agreed-upon activities the patient would carry out alone, after the session in hospital or at home, with the mitten on. ’s toys (e.g.
Results
Table 1: Demographic data of all patient groups
Age
Range Mean ± SD
Disease duration
Range Mean ± SD Group A Group B
43-74 49-70 53.90 ± 10.87 5-11 55.70 ± 6.58 5-12 8.60
± 2.71 9.00 ± 2.67
P. value
>0.05
>0.05
Table 2: Baseline assessment between both groups
FMA
Group A 35.70 ±9.44
ARAT
29.3 ±10.32
RMT (% of output) Amplitude of MEPs (mV) CMCT (msec)
70.1
±9.93
0.64
±0.41
9.65
±1.96
Group B 34.30 ±10.37 30.20 ±10.54 69.80
±12.38
0.63
± 0.32 10.82
± 1.71
P value >0.05
>0.05
>0.05
>0.05
>0.05
Table3: Comparison between clinical assessment scales in both groups before and after rehabilitation .
Group Before
Mean ± SD
After
Mean ± SD FMA ARAT
A B A B 35.70 ±9.44
34.30
±10.37 36.78
±9.18
51.20
±6.83 >0.05
<0.05* 29.3 ±10.32
30.20
±10.54 32.80
±9.46
48.00
±6.34 >0.05
<0.05*
Table (4 ): Comparison between both groups as regards FMA & ARAT scale mean improvement in each group after end of rehabilitation therapy
Group A Group B
Mean ± SD Mean ± SD
Z-test
) Sig.(p ) FMA .Change
ARAT .Change
1.08
± 0.21 16.90
± 9.93 -4.322
3.50
± 1.22
17.80
± 6.75
-3.723
<0.05
<0.05
60 51.2
figure (1): Comparison of Fugel Meyer assessment scale between both groups before and after therapy
36.7
after therapy 50 35.7
34.3
40 30 group B groupA 20 10 0 before therapy
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figure (2): Comparison of action research arm test between both groups before and after therapy
32.8
after therapy 48 50 29.3
30.2
40 30 group B groupA 20 10 0 before therapy
Table 5: Comparison between MEPs parameters in both groups before and after rehabilitation
MEP Parameter Group Before Mean ± SD After Mean ± SD
P value
RMT (% of output) A B Amplitude of MEPs (mV) CMCT (msec) A B A B
70.1
± 9.93 69.80
± 12.38
67.82
± 5.74 62.80
± 11.85
>0.05
0.008* 0.64
± 0.41 0.63
± 0.32
0.96
± 0.36 1.25
± 0.53
>0.05
0.000* 9.65
± 1.96 10.82
± 1.71
9.38
± 2.44 8.91
± 2.30
>0.05
0.000*
MEPs after cortical and cervical motor root stimulation of both sides in a patient with left cerebral infarction. Affected side CMCT=26.7 -15.6 =11.1 msec (C &D) and normal side CMCT=22-14.1=7.9 msec (A & B).
(A) TMCT of normal side (C) TMCT of affected side (B) Peripheral latency of normal side (D) Peripheral latency of affected side
Conclusion
• On the contrary to conventional rehabilitation therapy, the modified CIMT revealed a significant functional improvement in acute stroke patients denoting that m-CIMT might be a more efficient treatment strategy. • Furthermore, improvement of MEP parameters reflects the impact of training on cortical plasticity.