The impact of bilateral therapy on upper limb function after chronic stroke: a systematic review

 So EXACTLY WHOM DID YOU CONTACT TO GET FURTHER RESEARCH DONE? Did nothing, didn't you?

The impact of bilateral therapy on upper limb function after chronic stroke: a systematic review

CHRISTOPHER PAUL LATIMER, JUSTINE KEELING, BRODERICK LIN, MEREDITH HENDERSON & LEIGH ANNE HALE Centre for Physiotherapy Research, University of Otago, Dunedin, New Zealand Accepted November 2009  

 

Abstract  

 

Purpose.  

To determine the evidence for bilateral therapy interventions aimed at improving upper limb (UL) function in adults with a range of UL activity limitations due to a first time chronic stroke. Method. Seven databases were searched prior to 2008 for articles reporting experimental studies investigating bilateral UL interventions on functional outcome in participants with a first stroke, 6 or more months prior. Included articles were evaluated with the quality index, a tool which evaluates the quality of both randomised and non-randomised studies. Data relating to study design and functional outcome were extracted.  

 

Results.  

 

Nine articles were included; three reported on randomised controlled trials (RCT) and six on cohort studies. Eight studies incorporated a mechanical device as their bilateral intervention. Bilateral arm training with rhythmic auditory cueing (BATRAC) was the most commonly used mechanically based intervention, and three of the four uncontrolled BATRAC studies reported significant improvements in UL function post-intervention, however these results were not substantiated by a RCT study of the BATRAC intervention. One study demonstrated significant functional improvements after 6 days of training with a non-mechanical bilateral task. Of the four studies that performed a follow-up assessment, three reported significant improvement in UL function. Quality index ratings of the included studies ranged from 18 to 25 out of 27.  

 

Conclusion. 

 

 There is some evidence that bilateral therapy improves function in adults with chronic stroke, however more quality RCTs are required to strengthen this evidence. Keywords: Bilateral therapy, upper limb, stroke 

 

  Introduction 

 

  Stroke is the third most common cause of mortality and the leading cause of adult disability in the developed world [1]. The current incidence of stroke in western countries is high; approximately 1 million Europeans [2], more than 795,000 Americans [1], and over 60,000 Australians [3] experience a stroke each year. The ongoing social and economic cost of stroke causes additional pressure on health care funding and rehabilitation services. In the United States alone this equates to around $68.9 billion dollars annually [1]. Population growth combined with the ageing population, declining mortality rates and rising stroke incidence suggests that this financial burden will continue to rise [2,4]. As a result, research is focused on the development of cost-effective and efficient approaches to stroke rehabilitation. One of the most important aspects of stroke rehabilitation is the regaining of function in the affected upper limb (UL) as this relates directly to functional independence [5]. A systematic review reported that functional task orientated training appears to have positive effects on functional outcomes, compared with impairment focused interventions [6]. Constraint induced therapy (CIT) is a functional task orientated intervention that has been shown to significantly improve UL function after stroke [7,8]. CIT restricts the use of the non-paretic limb to promote functional movement of the affected UL. The proposed physiological basis underpinning CIT is the reactivation of dormant neuromuscular pathways [9–11]. This notion was first proposed by Taub in 1980 [12], who suggested that encouraging use of the affected limb led to a corresponding increase in cortical representation, which he believed provided the neurological basis for permanent functional gains of the affected extremity. However, a number of limitations regarding the use of CIT exist. For example, CIT requires patients to meet strict inclusion criteria, such as being able to voluntarily achieve at least 108 of wrist extension and thumb abduction of the paretic side, to participate in this type of therapy [13]. In a clinical setting CIT is very personnel and resource intensive, while in the community there are issues of patient safety and reduced functional independence due to constraint of the non-paretic limb [14]. This decreased functional independence may result in reduced patient compliance [14]. Furthermore, many activities of daily living (ADLs) are bimanual in nature and require complimentary and coordi- nated movement of the UL [15,16]. These realisa- tions have prompted the development of a variety of bimanual interventions for UL stroke rehabilita- tion [16]. Although the concept of bimanual training is not new, the first investigation into the use of bilateral therapy in UL rehabilitation in people with hemi- plegic stroke was conducted by Mudie and Matyas in 1996 [17], with positive results. Bilateral therapy involves the use of both ULs either simultaneously or sequentially [18], whereby the intact UL facilitates relearning of the spatial and temporal parameters required for motor recovery in the paretic UL [19,20]. Importantly, the principles of forced use and task specificity underlying CIT are retained with bilateral therapy without the need to constrain the unaffected UL [5,21]. In addition, it is believed that the performance of bilateral movements may enable activation of the damaged hemisphere by way of inter-hemispheric connections [22–24]. Following stroke it has been shown that using transcranial magnetic stimulation techniques the normal symme- trical transcallosal inhibition is disrupted and an imbalance occurs resulting in over-excitation of the contralesional hemisphere and excessive inhibition of the ipsilesional hemisphere. It is suggested that synchronous bilateral UL movements are a motor- based priming strategy that facilitate a re-balance of these systems. In a sample of 32 adults with chronic stroke, synchronous bilateral UL movements re- sulted in significant increase in ipsilesional hemisphere excitability, in transcallosal inhibition from ipsilesional to contralesional hemispheres and in intracortical inhibition within the contralesional hemisphere in the experimental group. Additionally, the experimental group had significant and sustained improvement in UL function [23]. Since the original publication by Mudie and Matyas (1996) [17], there have been numerous studies addressing the effect of bilateral interventions on patients with hemiplegic stroke. Although many studies report positive outcomes using bilateral interventions, some studies failed to demonstrate any functional gains [15]. Rose and Winstein (2004) [25] have suggested that this may be due to the variety of bimanual interventions currently employed in the literature. In this systematic review, we aimed to determine the evidence for bilateral therapy interventions aimed at improving UL function in adults with chronic stroke resulting in a range of UL activity limitations. Previous systematic reviews of bilateral therapy effectiveness have primarily focused on kinematic variables, cortical mapping and patients at various stages of stroke recovery, and not on functional outcome [20,25–27]. As most functional recovery up to six months post-stroke is postulated to occur as a result of spontaneous recovery [28–31], we concentrated on studies reporting outcome of participants with chronic stroke (more than 6 months poststroke).

 

More at link.