Abstract
Background
Repetitive sensory stimulation (RSS) is a therapeutic approach which involves repeated electrical stimulation of the skin’s surface to improve function. This rapid systematic review aimed to describe the current evidence for repetitive sensory stimulation (RSS) in rehabilitation of the upper-limb for people who have had a stroke.
Main text
Methods: Relevant studies were identified in a systematic search of electronic databases and hand-searching in February 2020. The findings of included studies were synthesized to describe: the safety of RSS, in whom and when after stroke it has been used, the doses used and its effectiveness.
Results
Eight studies were included. No serious adverse events were reported. The majority of studies used RSS in participants with mild or moderate impairments and in the chronic stage after stroke. Four studies used RSS in a single treatment session, reporting significant improvements in strength and hand function. Findings from longitudinal studies showed few significant differences between control and experimental groups. Meta-analysis was not possible due to the heterogeneity of included studies.
Conclusions
This review suggests that there is insufficient evidence to support the use of RSS for the upper-limb after stroke in clinical practice. However, this review highlights several clear research priorities including establishing the mechanism and in whom RSS may work, its safety and optimal treatment parameters to improve function of the upper-limb after stroke.
Background
Upper-limb impairments are the most common deficit after stroke and are reported by at least 70% of people after stroke [1]. Recovery of the upper-limb after stroke is problematic; whilst two-thirds of people after stroke go on to walk independently, less than 20% recover full upper-limb function and over half have not regained even basic functions of the upper-limb after several years [1, 2].
Identifying efficacious treatments for the upper-limb is vital to improve function and well-being after stroke [3]. The use of electrical stimulation for rehabilitation has been recognized as a promising therapy [4, 5] and has featured in clinical stroke guidelines [6].
Repetitive sensory stimulation (RSS) is a form of electrical simulation which aims to promote improvements in motor function [7]. It is often delivered to the skin via pads or embedded in a glove [5, 8]. This type of sensory stimulation has also been referred to as electrical somatosensory stimulation (ESS) [9, 10], repetitive peripheral sensory stimulation (RPSS) [8, 11], peripheral nerve stimulation (PNS) [12] and peripheral sensory stimulation (PSS) [13] but is distinct from functional electrical stimulation which requires provision of the electrical stimulation alongside an attempted movement [14]. It is hypothesized that RSS may promote motor function by inducing cortical plasticity [15], including both functional changes in neurons and synapses, and structural changes such as changes in synapse formation, elimination, and morphology [16].
As a practical intervention, RSS may provide several benefits if it can be shown to be safe and effective. Unlike many treatments to improve function after stroke, it can be used with those people who have severe paresis of the upper-limb and so may provide a window for rehabilitation in those who could not otherwise undergo many other forms of physical therapy. The passive nature of the RSS intervention does not necessitate constant supervision by a therapist other than assistance to don and doff the RSS apparatus. Consequently, it could deliver additional benefit to patients without significantly increasing demands on already stretched therapist’s time. However, a recent survey indicated that over half of occupational and physiotherapists rarely or never use any form of electrical stimulation for the upper-limb after stroke (n = 78 from 142) [17]. Therefore, there is a clear need to inform therapists about the evidence underpinning the use of RSS so that they can make well-reasoned choices when considering investing in the equipment and training RSS requires. This literature review contributes to this process by providing a structured description, with focus on the key information needed by clinicians, of the current evidence evaluating RSS for the upper-limb after stroke, specifically:
- its safety,
- in whom and when after stroke it has been used,
- the dose of RSS (including the frequency, intensity, duration and settings) used, and
- its effectiveness.
The findings of this review will highlight areas where further research is needed to underpin the evidence base in addition to informing current practice by providing a guide for therapists who might be considering using RSS. […]
TBI Rehabilitation 