Journal of Rehabilitation Medicine 51-10 | Page 4

724 C. Shackleton et al. ground powered lower limb exoskeletons, including Ekso (Ekso Bionics, Richmond, CA, USA) and ReWalk (ReWalk Robotics Inc., Marlborough, MA, USA) (5–8). These lightweight exoskeletons are rechargeable bionic devices with motorized joints that are worn over the lo- wer extremities (4). They enable individuals with lower extremity weakness to stand up and walk with a natural, full weight-bearing, and reciprocal gait (3). Several studies have investigated the benefits and safety of using powered robotic exoskeletons as a newly developed technology within SCI rehabilitation. However, these studies consist primarily of case-series or single-intervention trials, all with short intervention periods (5, 9). Several systematic reviews exist on the effectiveness of various forms of locomotor training after SCI, including over-ground and treadmill-based training, hybrid exoskeletons and orthotic walking aids (5, 9, 10). These reviews consider ambulatory function and safety as primary concerns, while user-satisfaction and other secondary health benefits are seldom reported. To our knowledge, no reviews have analysed cardiovas- cular outcomes from robotic locomotor training (RLT) interventions. Despite the depth of reviews covering RLT, to date, only a single review by Miller et al. (9) has performed a meta-analysis of the effect of over-ground RLT on functional and health outcomes. Therefore, this systematic review aims to add to the growing field of interest and development surrounding RLT by updating and building on the quantitative results previously established by Miller et al. (9). In addition, with a larger amount of literature available on this topic, a comprehensive overview of all the available evidence is essential to support the clinical application of RLT for rehabilitation after SCI. Conse- quently, this review aims to examine the effectiveness of over-ground powered exoskeletons as a tool for SCI rehabilitation by investigating gait parameters, cardiovascular demands, secondary health outcomes, including spasticity, pain and user-satisfaction. METHODS Search strategy A comprehensive review of the existing literature was underta- ken using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The following 6 electronic databases were searched for peer-reviewed journals published in English before 3 April 2018: PubMed, Cochrane Library, Web of Science, Scopus, EBSCOhost (CINAHL and Health Source Nursing/Academic) and EI Compedex Engine- ering Village. There was no limitation on included publication years, considering that the over-ground robotic exoskeletons did not receive USA Food & Drug Admministration/European Com- mision (FDA/CE) approval pre-2012. The PICOs framework was used to refine the search to individuals with SCI involved www.medicaljournals.se/jrm in over-ground locomotor training using robotic exoskeleton devices. The search terms included a combination of MeSH keywords and free-text terms (Table SI 1 ). Study selection Two reviewers independently selected and assessed the studies for inclusion eligibility. With the assistance of a third reviewer, any disagreements were resolved by discussion and consensus. Titles and abstracts were initially screened to exclude all review articles, conference proceedings, commentaries, letters, book chapters, animal or in vitro studies. Studies with fewer than 3 participants were excluded to eliminate bias inherent with case reports. Full texts were excluded if mixed diagnoses were inclu- ded, SCI-specific data were not reported, training was limited to a treadmill or the protocol utilized upper body exoskeletons, orthotic devices or hybrid (electrical stimulation) exoskeletons. Duplicate items were excluded preceding the screening process. Manual searches of reference lists from relevant articles were completed. Of the 900 articles initially identified, 39 met the selection criteria in both the title and abstract, and 22 of these were eliminated after reading the full text. Ultimately 17 studies were included from the online databases and an additional 10 from scanning the references of relevant articles (Fig. 1). Data extraction Two reviewers independently extracted the data from the included studies using a pre-established data abstraction table (Table I). Authors were contacted for further information if required. Participant and experimental details were summarized for each study, and outcome variables were tabulated provided they were reported by a minimum of 3 of the included studies. Non-tabulated results are shown in the Appendix SI 1 . Outcome measures Walking performance outcomes included: (i) the 6-min walk test (6MWT), measures the distance and velocity walked over a 6-min period, and serves as an indicator of submaximal aerobic capacity; (ii) the 10-metre walk test (10MWT) measures the velocity achieved during a 10-m walk; (iii) Timed Up and Go (TUG) tests the time required to stand up, balance and sit down again. Cardiovascular demand outcomes included heart rate (HR), blood pressure (BP) and rating of perceived exertion (RPE). RPE values were self-reported according to the Borg 6–20 scale. Secondary complications, including spasticity and pain, were measured using subjective ratings: numeric rating scale of 0–10 for spasticity and 0–6 for pain, as well as visual analogue scales (VAS) using a 10-cm ruler and a marker that the participant moves to the point indicating the intensity of pain. Clinical tests included the Modified Ashworth Scale and the Spinal Cord As- sessment for Spastic Reflexes. User-satisfaction utilized a variety of subjective rating questionnaires assessing the acceptability of the exoskeleton device and quality of life (QoL) scores. Quality criteria The quality of evidence of the extracted data was assessed accor- ding to the Grading of Recommendations, Assessment, Develop- http://www.medicaljournals.se/jrm/content/?doi=10.2340/16501977-2601 1