¹Institute of Occupational and Social Medicine and Health Services Research, University Hospital of Tübingen, Tübingen, Germany
²Institute for Occupational Safety and Health of the German Social Accident Insurance, Sankt Augustin, Germany
³Health Centre North, AUDI AG, Ingolstadt, Germany
⁴Institute of Occupational and Social Medicine, TU Dresden, Dresden, Germany
⁵Federal Institute for Occupational Safety and Health, Berlin, Germany
⁶Neurological University Hospital, BG University Hospital Bergmannsheil GmbH, Bochum, Germany
⁷Centre for Orthopaedics, Schön Clinic Bad Staffelstein, Bad Staffelstein, Germany
⁸Department of Orthopedics and Trauma Surgery, Catholic Clinic Bochum, Ruhr University Bochum, Bochum, Germany

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Introduction: Specific work characteristics like handling heavy loads, repetitive lifting, static postures, and overhead work play an important role in the development of work-related musculoskeletal disorders (WRMSD). Potential interventions for relieving employees exposed to these physically demanding occupational tasks and for WRMSD prevention could be implementation of exoskeletons, which are assistive devices worn directly on the body aiming to reduce physical loads on particular body parts. To support occupational practitioners, a German medical guideline on the use of exoskeletons for preventing WRMSD was published in 2020 and is currently being updated.

Methods: The 2020-guideline was a consensus-based guideline (level S2k) including expert opinions supported by published scientific studies. The update is accompanied by an upgrade to a combined evidence- and consensus-based guideline (level S3) including a systematic literature search and assessment along with expert opinions from a representative body of professional societies and advisory institutions. In a structured consensus conference, independently moderated, the developed recommendations and key statements are voted on and adopted.

Results: Systematic searches in four databases and one trial register resulted in 1,467 records. Two reviewers independently screened 1,034 unique records and selected 199 reports that met the eligibility criteria. Only four studies (five reports) were longitudinal field studies that could serve as evidence base for the current guideline regarding primary and secondary prevention. No study dealt with tertiary prevention. Studies were judged on risk of basis using ROBINS-I V2 and quality of evidence using Oxford Levels of Evidence. All studies had a moderate or high risk of bias and the final level of evidence was 3 or 4 (after downgrading based on sample size, potential conflict of interest, statistical significance level adjustments, intervention period, risk of bias). In general, the body of literature addressed short-term effects, mostly conducted in laboratory environments. It clearly shows that effects of the exoskeleton depend on the selected occupational task and anthropometric characteristics of the user and that usability and wearing comfort may be key elements for successful implementation. The 199 selected reports were considered by all experts to derive and consent recommendations.

Discussion: The three studies on primary prevention could not indicate a clear effect of wearing exoskeletons compared to not wearing exoskeletons on musculoskeletal disorders and symptoms among healthy employees. The one study on secondary prevention showed that wearing exoskeletons had a pain-reducing effect compared to not wearing an exoskeleton among workers with unspecific back pain.

Conclusion: The evidence that exoskeletons can play a preventive role in the development of WRMSD is very limited. This is an appeal that further research is needed: conducting high-quality longitudinal randomized controlled trials; being aware that the effect of wearing exoskeletons depends on the occupational task and characteristics of the wearer; warranting acceptance of exoskeleton implementation at all hierarchical levels.