Effects of industrial back-support exoskeletons on body loading and user experience: an updated systematic review

Abstract

This study is an updated systematic review of papers published in the last five years on industrial back-support exoskeletons. The research questions were aimed at addressing the recent findings regarding objective (e.g. body loading, user performance) and subjective evaluations (e.g. user satisfaction), potential side effects, and methodological aspects of usability testing. Thirteen studies of active and twenty of passive exoskeletons were identified. The exoskeletons were tested during lifting and bending tasks, predominantly in laboratory settings and among healthy young men. In general, decreases in participants' back-muscle activity, peak L5/S1 moments and spinal compression forces were reported. User endurance during lifting and static bending improved, but performance declined during tasks that required increased agility. The overall user satisfaction was moderate. Some side effects were observed, including increased abdominal/lower-limb muscle activity and changes in joint angles. A need was identified for further field studies, involving industrial workers, and reflecting actual work situations.

An ergonomic assessment tool for evaluating the effect of back exoskeletons on injury risk

“…This modification of LiFFT is logical because the back moment provided by the exo reduces that moment borne by the biological back extensors (e.g., muscles, ligaments). This biological offloading is well supported by prior literature using electromyography (EMG), force-instrumentation, and musculoskeletal modeling (Bär et al, 2021;Howard et al, 2020;Kermavnar et al, 2020;Lamers and Zelik, 2021). For instance, Lamers et al (2020) evaluated assistance benefits of a soft, passive-elastic back exo using two separate analyses -EMG, and a physics-based moment balance -and found the magnitude of back offloading estimated by each analysis to be similar.…”

“…We recommend the use of physics-based (lumbar moment) analysis for assessing back exos, particularly for devices or assistance levels where EMG studies have already been conducted that confirm consistency with moment-based estimates, and where evidence exists indicating there is not substantial co-contraction of the abdominal muscles or major changes to lifting kinematics. Of note, most studies on back exos have not observed abdominal muscle activity to increase during lifting or bending (Kermavnar et al, 2020). For instance, Lamers et al (2020) found no substantial changes to abdominal muscle activity with vs. without a soft, passive-elastic back exo, and that abdominal EMG did not exceed 5% maximum voluntary contraction with or without the exo.…”

“…For instance, Lamers et al (2020) found no substantial changes to abdominal muscle activity with vs. without a soft, passive-elastic back exo, and that abdominal EMG did not exceed 5% maximum voluntary contraction with or without the exo. The degree to which lifting kinematics change or do not change depends on the type of exo and task (Kermavnar et al, 2020). For instance, several studies on passive exos (e.g., Lamers et al, 2018;Madinei et al, 2020) found minimal differences in lifting kinematics while wearing vs. not wearing an exo.…”

“…1). Exos have been shown to reduce musculoskeletal forces (Bär et al, 2021;Howard et al, 2020;Kermavnar et al, 2020;Lamers and Zelik, 2021), a key risk factor for overexertion injuries in the workplace Marras et al, 1993;Norman et al, 1998). Some early adopters have classified exos as personal protective equipment (PPE), while others consider them to be engineering controls, or tools.…”

Exoskeletons in Nursing and Healthcare: A Bionic Future

“…Similarly, Tsuzura et al (2013) proposed a motordriven power suit to help caregivers lift and move heavy objects. A more recent review of the scientific evidence on back support exoskeletons found 13 additional studies and reported decreases in back muscle activity and spinal compression forces but performance tended to decline where tasks required more agile movements (Kermavnar et al, 2021). However, the majority of these studies were tested in a laboratory with healthy subjects and none were demonstrated in healthcare.…”