title: Ergonomic evaluation of a wearable assistive device for overhead work.
abstract: Overhead work is an important risk factor for upper extremity (UE) musculoskeletal disorders. We examined the potential of a mechanical arm and an exoskeletal vest as a wearable assistive device (WADE) for overhead work. Twelve participants completed 10 minutes of simulated, intermittent overhead work, using each of three payloads (1.1, 3.4 and 8.1 kg) and with/without the WADE. Ratings of perceived discomfort (RPDs) and electromyography (EMG) were obtained for the upper arms, shoulders and low back. Using the WADE, UE RPDs decreased by ∼50% with the heavier payloads, whereas smaller (∼25%) and non-significant increases in low-back RPDs were found and were relatively independent of payload. Changes in RPDs with WADE use were consistent with physical demands indicated by EMG, though EMG-based differences in fatigue were less apparent. Participants generally preferred using the WADE, particularly with heavier payloads. These results supported the potential utility of a WADE as an intervention for overhead work.
authors.affiliation: a Department of Industrial & Systems Engineering , Virginia Tech , Blacksburg , VA , USA.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Rashedi
authors.forename: Sunwook
authors.initials: S
authors.lastname: Kim
authors.forename: Maury A
authors.initials: MA
authors.lastname: Nussbaum
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Agnew
mesh_terms: D000328:Adult; D001132:Arm / Q000502:physiology; D004576:Electromyography; D006804:Ergonomics / Q000379:methods*; D006801:Humans; D017770:Lifting / Q000009:adverse effects*; D008161:Lumbosacral Region / Q000502:physiology; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology; D012656:Self-Help Devices / Q000592:standards*; D012782:Shoulder / Q000502:physiology; D014937:Work / Q000502:physiology
keywords: exoskeleton; overhead work; shoulder; wearable assistive device