Interventions for sensory impairment in the upper limb after stroke
Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
The objectives of this review are to determine the effectiveness of interventions that target upper limb sensory function after stroke. The primary outcomes considered for this review will be those related to sensory function but outcomes related to body impairments, activity limitations, and participation will be included if available.
Background
Stroke is the leading cause of disability and the third or fourth leading cause of death both in the United States of America (USA) and many western countries around the world (Eaves 2000; HSAO 2001; HSFC 2005; NSFA 2005). Pendlebury et al concluded that approximately one million strokes occur each year in Europe, making it the most common neurological disorder (Pendlebury 2004). There are three million permanently disabled stroke survivors in the USA. In the USA in 2006 the American Stroke Association estimated the costs of stroke (both direct and indirect) to be $57.9 billion (ASA 2006). In the United Kingdom, stroke accounts for approximately 6% of total National Health Service and social services expenditure, with most of the cost associated with the resulting chronic disability (Pendlebury 2004). Approximately 25% of chronic disability in Australia is due to stroke, costing the Australian economy over $1.3 billion annually (ASPSC 2004). There are 300,000 Canadians living with the effects of stroke costing the Canadian economy about $2.7 billion per year (HSFC 2005). Recognition of the importance of rehabilitation services in the management of conditions that affect people's functional abilities is growing. In Canada and the USA, those who require rehabilitation for stroke make up the largest category of rehabilitation patients and have the third longest length of inpatient stay (Hopman 2003). The cost of stroke is expected to continue to grow world wide over the next two decades due to the increasing age of the population (Pendlebury 2004).
The most common deficit after stroke is hemiparesis of the contralateral upper limb, with more than 80% of those with stroke experiencing it acutely and more than 40% chronically (Cramer 1997). Upper limb impairments continue to limit the functional independence and satisfaction for 50% to 70% of stroke survivors, and only 5% of survivors who initially experienced complete paralysis achieve functional use of their arm (HSAO 2001). Exploration of the environment and mastery and participation in daily occupations are intimately associated with both movement and sensation. Sensory deficits after stroke are common with prevalence rates variously reported to be 11% to 85% (Yekutiel 2000), 65% (Carey 1993), 60% to 74% (Hunter 2002), and 100% (Kent 1965; Rand 2001). This variability among the studies is thought to be related to differences in assessment and definition of sensory impairment, and study design (Yekutiel 2000). The sensory deficits do not appear to be confined to the contralateral upper limb, with several studies noting significant impairment in the ipsilateral upper limb after stroke in 51% to 66 % of survivors (Kent 1965). While the level of impairment in the ipsilateral upper limb is generally considered less than that of the contralateral upper limb, in some cases moderate to severe deficits have been reported and deficits have also been noted to persist for a period of years after stroke. The incidence of ipsilateral impairment generally cited varies from 12% to 26% (Carey 1995).
Functionally the problems resulting from sensory deficits after stroke can be summarized as (1) loss of detection of sensory information, (2) disturbed performance of motor tasks that require somatosensory information, and (3) the influence on the rehabilitation outcome (Hunter 2002). The loss of detection of protective and touch sensation has been noted in up to 65% of all stroke survivors (Carey 1993). The types of sensory deficits experienced after stroke include delayed perception, uncertainty of responses, changes in sensory thresholds, fatigue, altered time for sensory adaptation, sensory persistence, and altered nature of the sensation (Hunter 2002; Robertson 1994). Impairment in proprioception (52%), vibration (44%), light touch (37%), and loss of pinprick sensation (35%) were also noted (Hunter 2002). Sensation is essential for safety even if there is adequate motor recovery (Yekutiel 2000). The development of secondary complications such as sores, abrasions, and shoulder hand syndrome has been associated with the impairment of sensation (Rand 2001). Sensory impairment has also been found to be directly associated with the development of shoulder pain and subluxation (Chang 1995; Gamble 2000). Sensory information has also been noted to be essential for sexual communication and participation (Carey 1993; Rand 2001).
When there is impairment in the ability to detect and process sensory data, the stroke survivor will have difficulty exploring and relating to their environment (Dannenbaum 1993; Yekutiel 2000). It is postulated that stroke survivors who have sensory impairments do not use their limbs to the full motor potential (van der Lee 1999). The spontaneous use of the upper limb has been noted to significantly decrease when cutaneous sensory processing is impaired (Carey 1993; Rand 2001). This continued disuse of the affected extremity leads to a further decrease in skilled movement and particularly with functional skills that require a constant sustained muscle contraction (Dannenbaum 1993). This continues to contribute to further the pattern of learned non use. The quality of movements of the upper limb is also impaired in the presence of sensory impairments (Rand 2001). Survivors were found to have impairments in force control, fine motor manipulation of objects, sensory ataxia, decreased grasp and manipulative skills, and changes in prehension patterns (Aruin 2005; Carey 1995; Robertson 1994; Yekutiel 2000). The level of motor impairment was not simply proportional to the level of sensory impairment (Dannenbaum 1993).
Sensory deficits have been shown to predict poor functional outcome after stroke, including increased length of hospitalization, lower levels of discharge home, and increased mortality rates (Carey 1995; Rand 2001; Yekutiel 2000). While proprioception status soon after stroke has been reported to be a reliable predictor of long term motor recovery the evidence is not so clear, as some studies have showed no association between functional status on discharge and somatosensory impairment (Carey 1995). In a study of stroke survivors in the first six weeks of recovery, researchers found no significant difference in outcomes between those who had both motor and proprioceptive deficits and those who had pure motor deficits (Rand 1999), concluding that all patients with upper limb deficits after stroke can make significant gains. Tactile extinction on the left side of the body (of double simultaneous stimulation) was shown to be the single most important predictor of functional outcome (Rose 1994). There are many factors that contribute to the varying outcomes of these studies. These include the definitions of sensory impairment use, how it was measured, and the time lapsed since the initial impairment but all agree that sensory impairments are of significant importance (Carey 1995).
Although sensory impairments significantly limit the ability to functionally use the upper limb after stroke and increases the risk of secondary complications, to date little is known about the effectiveness of interventions that are used to address this issue. A systematic review of interventions for sensory impairment after stroke will provide important information about the effectiveness of these intervention strategies during stroke rehabilitation.
Objectives
The objectives of this review are to determine the effectiveness of interventions that target upper limb sensory function after stroke. The primary outcomes considered for this review will be those related to sensory function but outcomes related to body impairments, activity limitations, and participation will be included if available.
Methods
Criteria for considering studies for this review
Types of studies
We will include randomized controlled trials which aim to improve function or remediate sensory impairments of the upper limb following stroke by specifically focusing on interventions to address the sensory impairment. We will include controlled trials if participants are randomly or quasi‐randomly assigned to one of two or more treatment groups. We will also include trials with or without blinding of the participants, therapists, or evaluators.
Types of participants
Participants in the trials to be included must be adults (18 years and over) with a clinical diagnosis of stroke. This may be either hemorrhagic or ischemic stroke and does not necessarily need to be confirmed using imaging studies. The stroke would have resulted in the participants initially experiencing a disturbance in sensory function of the upper limb. A disturbance in sensory function will be defined as any impairment that impacted on sensory registration, perception, or discrimination, resulting from a cerebral vascular accident and where the primary sensory receptors are intact. We will include studies that have mixed etiology groups unless they have less than 50% of participants with stroke.
Types of interventions
Studies must specifically address interventions that are aimed at promoting the recovery of function or remediating sensory impairments, or both, of the upper limb by specifically focusing on interventions to address the upper limb sensory impairment in patients after stroke. These strategies may include the following: sensory re‐education, tactile kinesthetic guiding, repetitive sensory practice, or desensitization. We will also consider novel intervention strategies, that is those not identified above, if they are considered relevant. These interventions can be delivered as 'stand alone' or as an adjunct to conventional therapy.
Types of outcome measures
We will not exclude studies based on the use of specific outcome measures that are not listed below provided the outcome measure can be included in one of the following categories. The primary outcome measure will be measures of sensory function or impairment, including measures of touch, pain, temperature, vibration sense, position sense, movement sense, stereognosis, sustained pressure (Weinstein Enhanced Sensory Test), the depth sense aesthesiometer, and somatosensory evoked potentials. Such measures would also include components of tests such the Motor Assessment Scale and the Fugl‐Meyer, which are impairment‐based measures and address sensation. The perceived level of impairment or discomfort by the stroke survivor would also be included here.
The secondary outcomes will be measures of functional use of the upper limb and the ability to perform activities of daily living (that is activity or activity limitations). These will include functional measures of upper limb use (such as the Jebsen Taylor Hand Function Test or the Motor Activity Log), and global dependency scales or measures of activity limitation (activities of daily living such as the Barthel Index or the Functional Independence Measure). Scales that identify the survivors' perceived level of use and satisfaction with level and quality of upper limb use could also be included here. Death from any cause during the treatment will be considered here. Adverse effects will be included in data extraction and will be categorized by two review authors in consensus. Economic data, if available, will also be included in data extraction. The time frames for any follow up and the extent of the follow up will be included in data extraction and then categorized by the review authors.
We will also include outcomes related to participation (handicap or quality of life), such as the Stroke Impact Scale. Outcome measures will be recorded based on these categories, data extracted appropriately from the studies, and the review authors will come to a consensus as to which to include in the final analysis.
Search methods for identification of studies
See: 'Specialized register' section in Cochrane Stroke Group
We will search the Cochrane Stroke Group Trials Register. In addition, we will search the following electronic bibliographic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, latest issue), MEDLINE (1966 to present) (Appendix 1), EMBASE (1980 to present), CINAHL (1982 to present), AMED (1985 to present), PsycLIT (1974 to present), Science Citation Index (1945 to present), Social Science Citation Index (1956 to present) and LILACS (Latin American & Caribbean Health Sciences Literature) (1982 to present). We will also search the following specialist occupational therapy and physiotherapy databases: PEDro (http://www.cchs.usyd.edu.au/pedro/) and OTseeker (www.otseeker.com).
Current awareness
We will search the Excerpta Medica abstract journal Rehabilitation and Physical Medicine (Section 19 EMBASE) and the Index Medicus monthly bibliographic index.
Citation tracking and reference lists
Using key references, we will use the cited reference search in Science Citation Index to identify further studies. We will search the reference lists of all relevant articles identified.
Handsearching
We will search the last 10 to 20 years of the following journals: (the years selected will represent the timeframe of increased interest and research publications in this topic area).
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American Journal of Occupational Therapy
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OTJR: Occupation, Participation and Health
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Canadian Journal of Occupational Therapy
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Australian Journal of Occupational Therapy
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Physical Therapy
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Archives of Physical Medicine and Rehabilitation
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British Journal of Occupational Therapy
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Journal of Neurological Rehabilitation
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Physical and Occupational therapy in Geriatrics
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Occupational Therapy in Health Care
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Australian, Canadian and British Physical Therapy Journals
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Journal of Physical Medicine
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Stroke
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Head Trauma
To avoid duplication, we will check the Cochrane Master List of journals handsearched on behalf of The Cochrane Collaboration (http://www.cochrane.us/masterlist.asp) to identify handsearching already completed.
Additional searching
In an effort to identify further published, unpublished and ongoing trials we will:
(1) search for Doctoral and Masters' theses on the OT Search bibliographic database, the AOTA website, Dissertation Abstracts and Physical Therapy theses indexes;
(2) contact research and professional associations or foundations (such as the Medicine and Stroke Foundations in USA, UK, Canada, and Australia) to identify any other research that they know of;
(3) identify key researchers in the area and contact them with regards to unpublished research;
(4) search international clinical trials and research registers, such as the National Research Register (http://www.nrr.nhs.uk/search.htm), Current Controlled Trials (http://www.controlled‐trials.com/), and REHABDATA (http://www.naric.com/research/rehab/).
There will be no language or date restrictions on the electronic searches for trials.
Data collection and analysis
The primary review author will review the titles identified and eliminate obviously irrelevant studies; the abstracts for the remaining studies will be obtained. Using the titles and abstracts obtained from the searches, two review authors will independently complete the study selection form to determine if a study should be included or excluded or to state that they are unsure of this decision. Disagreements will be resolved by discussion based on the inclusion criteria.
Two review authors will then review the articles that have been considered appropriate for inclusion in the review and complete the data abstraction form with the following information.
Data retrieval
(1) Retrieval characteristics: source and date of publication, and authors.
(2) Sample characteristics: sex, age, sample size, diagnosis (right or left cerebrovascular accident areas specified), and other reported clinical variables listed as inclusion or exclusion characteristics.
(3) Sensory return group, as per the Heart and Stroke Association of Ontario definitions (HSAO 2001):
(a) early stage low level return;
(b) early stage high level return;
(c) late stage low level return;
(d) late stage high level return.
If information is not available to make this classification with all of the studies, studies will then be classified using the time period since the stroke occurred for the participants. The categories will defined by time since stroke of 0 to 3 months, more than 3 months to 6 months, more than 6 months to 12 months, and more than 12 months. If groups have less than 10 participants, then groups may be defined as 0 to 6 months, and more than 6 months.
(4) Assessment of study quality: two of the review authors will rate the quality of the studies. Where there is disagreement the third review author will be asked to rate the study, the rating which two of the three review authors selected will be the one used. If this does not occur further discussion will take place until agreement is reached among all three review authors. Selection bias, performance bias, detection bias, and attrition bias will be scored using the following scoring criteria and definitions from the Cochrane Handbook for Systematic Reviews of Interventions: A (adequate), B (unclear), and C (inadequate).
(5) Theoretical perspective: extract details the identified theoretical perspective if stated.
(6) Intervention: specific intervention technique: detail the specific intervention technique used in the study. Frequency (dosage): detail the specific intervention frequency.
(7) Follow‐up time period stated.
(8) Outcome measures.
(9) Adverse effects or side effects.
(10) Results: means, standard deviations, significance test, t, f, p values and directions of findings.
(11) Effect size: if not reported and sufficient information is provided, this will be calculated using the methodology outlined in Rosenthal (Rosenthal 1991). These will be calculated as r values and then will be displayed in binomial effect size display (BESD).
(12) Clinical reasoning decision making indicators identified, for example, movement, edema, pain, sensation level, subluxation, cognitive levels, perceptual issues, contraindications, exclusions from the study, complications reported or listed, inclusion criteria for the study, including time post stroke (Baker 2001).
Information from study authors: we will undertake a review of the data available and the information on the study design. If there are items that are unclear, the review author will indicate that it would be beneficial to contact the study authors to attempt to obtain the information needed. The review co‐ordinator will then attempt to do this.
Data analysis
We will then enter the data into the Review Manager software (RevMan 4.2), provided by The Cochrane Collaboration, using the double data entry facility to allow for error checking. We will use RevMan for data entry, analysis, and display.
The following analyses are planned:
(1) specific treatment for sensory impairment versus no treatment;
(2) specific treatment for sensory impairment versus conventional upper limb therapy;
(3) specific treatment for sensory impairment versus placebo sensory treatment;
(4) comparisons between different types of treatments for sensory impairment.
Studies where both the treatment and control group received conventional therapy and the only difference was that the treatment group also received specific treatment for sensory impairment were placed in the first group above.
For the primary outcome it is expected that the data will be continuous data. It is also anticipated that different studies will utilize different measurement scales for that outcome, and effect size will be calculated in RevMan as standardized mean difference (SMD) using the random‐effects model. For dichotomous secondary outcomes (death or appearance of adverse events), odds ratio (OR) will be used with 95% confidence intervals (CI).
A meta‐analysis is intended for this review. Heterogeneity will be examined prior to completing a meta‐analysis. This will be done for the overall list of studies involved and then for each individual subgroup, and will follow the recommendation in the Cochrane Handbook for Systematic Reviews of Interventions of at least 10 studies in a group for analysis. If there are less than 10 studies further analysis will not be done and narrative information will be provided. Heterogeneity will be calculated using the I‐square (I2) test. If I2 is greater than 50%, indicating that significant heterogeneity is detected, a sensitivity analysis will be conducted.
The sensitivity of the review to key decisions made will be tested by recalculating the analysis in the following manner:
(1) excluding studies of lower methodological quality (that is any graded C on a parameter);
(2) excluding unpublished studies.
Subgroup analysis will be undertaken for groups identified in section (3) of 'Data retrieval' above; sensory return group or time since stroke. Subgroups will also be formed based on the intervention technique used. Intention‐to‐treat analysis for all studies included in the review will also be undertaken if possible.
