Does mental practice improve the outcomes of upper extremity rehabilitation for individuals living with the effects of stroke?
Mental practice is a process through which an individual repeatedly mentally rehearses an action or task without actually physically performing the action or task. The goal of mental practice is to improve performance of those actions or tasks. Mental practice has been proposed as a potential adjunct to physical practice that is commonly performed by survivors of stroke undergoing rehabilitation.
We searched 10 electronic databases and two clinical trials databases in September 2019.
We included 25 studies with 676 study participants. Thirty-four per cent of participants were women. In all studies, participants were randomly allocated to groups. The studies, which were reported from nine countries, measured one or more of the following outcomes: arm function for real-life tasks appropriate to the upper limb (e.g. drinking from a cup, manipulating a doorknob), the amount and quality of movement in the arm, and activities of daily living. We sought but did not find evidence related to health-related quality of life, economic costs, and adverse events.
Our review of the available literature provided moderate-certainty evidence that mental practice, when added to other physical rehabilitation treatment, produced improved outcomes compared to use of the other rehabilitation treatment alone. Evidence to date shows improvements in arm function and arm movement. It is not clear whether (1) mental practice added to physical practice produces improvements in activities of daily living; (2) mental practice alone compared to conventional treatment is beneficial in improving motor control of the arm; (3) how much mental practice could produce the best results; (4) and whether mental practice is best used at a particular time after stroke. No adverse effects or harms were reported in any of the studies.
Certainty of the evidence
For mental practice added to other physical rehabilitation treatment compared to use of the other rehabilitation treatment alone, the certainty of evidence was moderate for arm function and arm movement outcomes based on some challenges in study design. The certainty of evidence was low for the activities of daily living outcome based on study design and the small number of participants included. For the mental practice compared to conventional treatment comparison, the certainty of evidence for the arm movement outcome was determined to be low for the same reasons.
Moderate-certainty evidence shows that MP in addition to other treatment versus the other treatment appears to be beneficial in improving upper extremity activity. Moderate-certainty evidence also shows that MP in addition to other treatment versus the other treatment appears to be beneficial in improving upper extremity impairment after stroke. Low-certainty evidence suggests that ADLs may not be improved with MP in addition to other treatment versus the other treatment. Low-certainty evidence also suggests that MP versus conventional treatment may not improve upper extremity impairment. Further study is required to evaluate effects of MP on time post stroke, the volume of MP required to affect outcomes, and whether improvement is maintained over the long term.
Stroke is caused by the interruption of blood flow to the brain (ischemic stroke) or the rupture of blood vessels within the brain (hemorrhagic stroke) and may lead to changes in perception, cognition, mood, speech, health-related quality of life, and function, such as difficulty walking and using the arm. Activity limitations (decreased function) of the upper extremity are a common finding for individuals living with stroke. Mental practice (MP) is a training method that uses cognitive rehearsal of activities to improve performance of those activities.
To determine whether MP improves outcomes of upper extremity rehabilitation for individuals living with the effects of stroke.
In particular, we sought to (1) determine the effects of MP on upper extremity activity, upper extremity impairment, activities of daily living, health-related quality of life, economic costs, and adverse effects; and (2) explore whether effects differed according to (a) the time post stroke at which MP was delivered, (b) the dose of MP provided, or (c) the type of comparison performed.
We last searched the Cochrane Stroke Group Trials Register on September 17, 2019. On September 3, 2019, we searched the Cochrane Central Register of Controlled Trials (the Cochrane Library), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycINFO, Scopus, Web of Science, the Physiotherapy Evidence Database (PEDro), and REHABDATA. On October 2, 2019, we searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform. We reviewed the reference lists of included studies.
We included randomized controlled trials (RCTs) of adult participants with stroke who had deficits in upper extremity function (called upper extremity activity).
Two review authors screened titles and abstracts of the citations produced by the literature search and excluded obviously irrelevant studies. We obtained the full text of all remaining studies, and both review authors then independently selected trials for inclusion. We combined studies when the review produced a minimum of two trials employing a particular intervention strategy and a common outcome. We considered the primary outcome to be the ability of the arm to be used for appropriate tasks, called upper extremity activity. Secondary outcomes included upper extremity impairment (such as quality of movement, range of motion, tone, presence of synergistic movement), activities of daily living (ADLs), health-related quality of life (HRQL), economic costs, and adverse events. We assessed risk of bias in the included studies and applied GRADE to assess the certainty of the evidence. We completed subgroup analyses for time since stroke, dosage of MP, type of comparison, and type of arm activity outcome measure.
We included 25 studies involving 676 participants from nine countries. For the comparison of MP in addition to other treatment versus the other treatment, MP in combination with other treatment appears more effective in improving upper extremity activity than the other treatment without MP (standardized mean difference [SMD] 0.66, 95% confidence interval [CI] 0.39 to 0.94; I² = 39%; 15 studies; 397 participants); the GRADE certainty of evidence score was moderate based on risk of bias for the upper extremity activity outcome. For upper extremity impairment, results were as follows: SMD 0.59, 95% CI 0.30 to 0.87; I² = 43%; 15 studies; 397 participants, with a GRADE score of moderate, based on risk of bias. For ADLs, results were as follows: SMD 0.08, 95% CI -0.24 to 0.39; I² = 0%; 4 studies; 157 participants; the GRADE score was low due to risk of bias and small sample size. For the comparison of MP versus conventional treatment, the only outcome with available data to combine (3 studies; 50 participants) was upper extremity impairment (SMD 0.34, 95% CI -0.33 to 1.00; I² = 21%); GRADE for the impairment outcome in this comparison was low due to risk of bias and small sample size. Subgroup analyses of time post stroke, dosage of MP, or comparison type for the MP in combination with other rehabilitation treatment versus the other treatment comparison showed no differences. The secondary outcome of health-related quality of life was reported in only one study, and no study noted the outcomes of economic costs and adverse events.