To assess the efficacy of two different passive back-support exoskeleton (BSE) designs, in terms of trunk muscle activity, perceived low-back exertion, and task performance.
Background
BSEs have the potential to be an effective intervention for reducing low-back physical demands, yet little is known about the impacts of different designs in work scenarios requiring varying degrees of symmetric and asymmetric trunk bending during manual assembly tasks.
Method
Eighteen participants (gender balanced) completed lab-based simulations of a precision manual assembly task using a “grooved pegboard.” This was done in 26 different conditions (20 unsupported; 6 supported, via a chair), which differed in vertical height, horizontal distance, and orientation.
Results
Using both BSEs reduced metrics of trunk muscle activity in many task conditions (≤47% reductions when using BackX™ and ≤24% reductions when using Laevo™). Such reductions, though, were more pronounced in the conditions closer to the mid-sagittal plane and differed between the two BSEs tested. Minimal effects on task completion times or ratings of perceived exertion were found for both BSEs.
Conclusion
Our findings suggest that using passive BSEs can be beneficial for quasi-static manual assembly tasks, yet their beneficial effects can be task specific and specific to BSE design approaches. Further work is needed, though, to better characterize this task specificity and to assess the generalizability of different BSE design approaches in terms of physical demands, perceived exertion, and task performance.
Application
These results can help guide the choice and application of passive BSE designs for diverse work scenarios involving nonneutral trunk postures.
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References
1.
Abdoli-EM.AgnewM. J.StevensonJ. M. (2006). An on-body personal lift augmentation device (PLAD) reduces EMG amplitude of erector spinae during lifting tasks. Clinical Biomechanics, 21, 456–465.doi:10.1016/j.clinbiomech.2005.12.021
2.
Abdoli-EM.StevensonJ. M. (2008). The effect of on-body lift assistive device on the lumbar 3D dynamic moments and EMG during asymmetric freestyle lifting. Clinical Biomechanics, 23, 372–380.doi:10.1016/j.clinbiomech.2007.10.012
3.
AlzuheriA.LuongL.XingK. (2010). Ergonomics design measures in manual assembly work. Paper presented at the 2010 Second International Conference on Engineering System Management and Applications.
4.
BaltruschS. J.van DieënJ. H.van BennekomC. A. M.HoudijkH. (2018). The effect of a passive trunk exoskeleton on functional performance in healthy individuals. Applied Ergonomics, 72, 94–106.doi:10.1016/j.apergo.2018.04.007
5.
BarrettA. L.FathallahF. A. (2001). Evaluation of four weight transfer devices for reducing loads on lower back during agricultural stoop labor. Paper presented at the ASAE Annual International Conference, Sacramento, USA. Paper Number. 01-8056.
6.
BenjaminiY.HochbergY. (1995). Controlling the false discovery rate: A practical and powerful approach to multiple testing. Journal of the Royal Statistical Society: Series B, 57, 289–300.doi:10.1111/j.2517-6161.1995.tb02031.x
BorgG. (2004). The Borg CR10 scale® folder. A method for measuring intensity of experience. Borg Perception.
9.
BoschT.van EckJ.KnitelK.de LoozeM. (2016). The effects of a passive exoskeleton on muscle activity, discomfort and endurance time in forward bending work. Applied Ergonomics, 54, 212–217.doi:10.1016/j.apergo.2015.12.003
10.
BurkeM. J.SarpyS. A.Smith-CroweK.Chan-SerafinS.SalvadorR. O.IslamG. (2006). Relative effectiveness of worker safety and health training methods. American Journal of Public Health, 96, 315–324.doi:10.2105/AJPH.2004.059840
11.
ChaffinD. B.AnderssonG.MartinB. J. (2006). Occupational biomechanics. Wiley-Interscience.
12.
ClemesS. A.HaslamC. O.HaslamR. A. (2010). What constitutes effective manual handling training? A systematic review. Occupational Medicine, 60, 101–107.doi:10.1093/occmed/kqp127
13.
CramJ. R. (2010). Cram's introduction to surface electromyography. Jones & Bartlett Learning.
14.
da CostaB. R.VieiraE. R. (2010). Risk factors for work-related musculoskeletal disorders: A systematic review of recent longitudinal studies. American Journal of Industrial Medicine, 53, 285–323.doi:10.1002/ajim.20750
15.
DaltroyL. H.IversenM. D.LarsonM. G.LewR.WrightE.RyanJ.ZwerlingC.FosselA, H.LiangM. H. (1997). A controlled trial of an educational program to prevent low back injuries. New England Journal of Medicine, 337, 322–328.doi:10.1056/NEJM199707313370507
16.
DavisM. A.OnegaT.WeeksW. B.LurieJ. D. (2012). Where the United States spends its spine dollars: Expenditures on different ambulatory services for the management of back and neck conditions. Spine, 37, 1693.doi:10.1097/BRS.0b013e3182541f45
17.
de LoozeM. P.BoschT.KrauseF.StadlerK. S.O'SullivanL. W. (2016). Exoskeletons for industrial application and their potential effects on physical work load. Ergonomics, 59, 671–681.doi:10.1080/00140139.2015.1081988
18.
FrostD. M.Abdoli-EM.StevensonJ. M. (2009). PLAD (personal lift assistive device) stiffness affects the lumbar flexion/extension moment and the posterior chain EMG during symmetrical lifting tasks. Journal of Electromyography and Kinesiology, 19, e403–e412.doi:10.1016/j.jelekin.2008.12.002
19.
FryarC. D.GuQ.OgdenC. L.FlegalK. M. (2016). Anthropometric reference data for children and adults: United States, 2011–2014. National Center for Health Statistics. Vital and Health Statistics, 3, 1–46.
20.
GodwinA. A.StevensonJ. M.AgnewM. J.TwiddyA. L.Abdoli-EramakiM.LotzC. A. (2009). Testing the efficacy of an ergonomic lifting aid at diminishing muscular fatigue in women over a prolonged period of lifting. International Journal of Industrial Ergonomics, 39, 121–126.doi:10.1016/j.ergon.2008.05.008
21.
GrahamR. B.AgnewM. J.StevensonJ. M. (2009). Effectiveness of an on-body lifting aid at reducing low back physical demands during an automotive assembly task: Assessment of EMG response and user acceptability. Applied Ergonomics, 40, 936–942.doi:10.1016/j.apergo.2009.01.006
22.
GriffithL. E.ShannonH. S.WellsR. P.WalterS. D.ColeD. C.CôtéP.FrankJ.Hogg-JohnsonS.LangloisL. E. (2012). Individual participant data meta-analysis of mechanical workplace risk factors and low back pain. American Journal of Public Health, 102, 309–318.doi:10.2105/AJPH.2011.300343
23.
HaightJ. M.BelwalU. (2006). Designing for an aging workforce. Professional Safety, 51, 20.
24.
HenselR.KeilM. (2019). Subjective evaluation of a passive industrial exoskeleton for lower-back support: A field study in the automotive sector. IISE Transactions on Occupational Ergonomics and Human Factors (just-accepted), pp. 1–10.
25.
HermensH.MerlettiR.FreriksB. (1996). European activities on surface electromyography. Paper presented at the Proceedings of the first general SENIAM (Surface EMG for Non Invasive Assessment of Muscles) workshop.
26.
HignettS. (2003). Intervention strategies to reduce musculoskeletal injuries associated with handling patients: A systematic review. Occupational and Environmental Medicine, 60, E6–6.doi:10.1136/oem.60.9.e6
27.
HunterS. L. (2001). Ergonomic evaluation of manufacturing system designs. Journal of Manufacturing Systems, 20, 429–444.doi:10.1016/S0278-6125(01)80062-5
28.
HuysamenK.de LoozeM.BoschT.OrtizJ.ToxiriS.O'SullivanL. W. (2018). Assessment of an active industrial exoskeleton to aid dynamic lifting and lowering manual handling tasks. Applied Ergonomics, 68, 125–131.doi:10.1016/j.apergo.2017.11.004
29.
JiaB.KimS.NussbaumM. A. (2011). An EMG-based model to estimate lumbar muscle forces and spinal loads during complex, high-effort tasks: Development and application to residential construction using prefabricated walls. International Journal of Industrial Ergonomics, 41, 437–446.doi:10.1016/j.ergon.2011.03.004
30.
KimS.NussbaumM. A.Mokhlespour EsfahaniM. I.AlemiM. M.JiaB.RashediE. (2018). Assessing the influence of a passive, upper extremity exoskeletal vest for tasks requiring arm elevation: Part II - "Unexpected" effects on shoulder motion, balance, and spine loading. Applied Ergonomics, 70, 323–330.doi:10.1016/j.apergo.2018.02.024
31.
KoopmanA. S.KingmaI.FaberG. S.de LoozeM. P.van DieënJ. H. (2019). Effects of a passive exoskeleton on the mechanical loading of the low back in static holding tasks. Journal of Biomechanics, 83, 97–103.doi:10.1016/j.jbiomech.2018.11.033
32.
LamersE. P.YangA. J.ZelikK. E. (2018). Feasibility of a biomechanically-assistive garment to reduce low back loading during leaning and lifting. IEEE Transactions on Biomedical Engineering, 651674–1680.doi:10.1109/TBME.2017.2761455
33.
LavenderS. A.KoP. -L.SommerichC. M. (2013). Biomechanical evaluation of the Eco-Pick lift assist: A device designed to facilitate product selection tasks in distribution centers. Applied Ergonomics, 44, 230–236.doi:10.1016/j.apergo.2012.07.006
34.
LeeH.KimW.HanJ.HanC. (2012). The technical trend of the exoskeleton robot system for human power assistance. International Journal of Precision Engineering and Manufacturing, 13, 1491–1497.doi:10.1007/s12541-012-0197-x
35.
LotzC. A.AgnewM. J.GodwinA. A.StevensonJ. M. (2009). The effect of an on-body personal lift assist device (PLAD) on fatigue during a repetitive lifting task. Journal of Electromyography and Kinesiology, 19, 331–340.doi:10.1016/j.jelekin.2007.08.006
36.
MadineiS.MotabarH.NingX. (2018). The influence of external load configuration on trunk biomechanics and spinal loading during sudden loading. Ergonomics, 61, 1364–1373.doi:10.1080/00140139.2018.1489068
37.
MadineiS.NingX. (2018). Effects of the weight configuration of hand load on trunk musculature during static weight holding. Ergonomics, 61, 831–838.doi:10.1080/00140139.2017.1387675
38.
MarrasW. S.MirkaG. A. (1993). Electromyographic studies of the lumbar trunk musculature during the generation of low-level trunk acceleration. Journal of Orthopaedic Research, 11, 811–817.doi:10.1002/jor.1100110606
39.
MilesJ.ShevlinM. (2001). Applying regression and correlation: a guide for students and researchers. Sage.
40.
NäfM. B.KoopmanA. S.BaltruschS.Rodriguez-GuerreroC.VanderborghtB.LefeberD. (2018). Passive back support exoskeleton improves range of motion using flexible beams. Frontiers in Robotics and AI, 5, 72.doi:10.3389/frobt.2018.00072
41.
NussbaumM. A.ChaffinD. B.BakerG. (1999). Biomechanical analysis of materials handling manipulators in short distance transfers of moderate mass objects: Joint strength, spine forces and muscular antagonism. Ergonomics, 42, 1597–1618.doi:10.1080/001401399184703
42.
PotvinJ.NormanR.WellsR. (1990). A field method for continuous estimation of dynamic compressive forces on the L4/L5 disc during the performance of repetitive industrial tasks. Paper presented at the Proceedings of the Annual Conference of the Human Factors Association of Canada.
43.
PunnettL.Prüss-UtünA.NelsonD.FingerhutM. A.LeighJ.TakS.PhillipsS. (2005). Estimating the global burden of low back pain attributable to combined occupational exposures. American Journal of Industrial Medicine, 48, 459–469.doi:10.1002/ajim.20232
44.
SilversteinB.ClarkR. (2004). Interventions to reduce work-related musculoskeletal disorders. Journal of Electromyography and Kinesiology, 14, 135–152.doi:10.1016/j.jelekin.2003.09.023
45.
ToxiriS.OrtizJ.MasoodJ.FernándezJ.MateosL. A.CaldwellD. G. (2017). A powered low-back exoskeleton for industrial handling: Considerations on controls. InWearable robotics: Challenges and trends (pp.287–291) Springer.
46.
UlreyB. L.FathallahF. A. (2013). Effect of a personal weight transfer device on muscle activities and joint flexions in the stooped posture. Journal of Electromyography and Kinesiology, 23, 195–205.doi:10.1016/j.jelekin.2012.08.014
47.
WehnerM.RempelD.KazerooniH. (2009). Lower extremity exoskeleton reduces back forces in lifting. Paper presented at the ASME 2009 Dynamic Systems and Control Conference.
48.
WestonE. B.AlizadehM.KnapikG. G.WangX.MarrasW. S. (2018). Biomechanical evaluation of exoskeleton use on loading of the lumbar spine. Applied Ergonomics, 68, 101–108.doi:10.1016/j.apergo.2017.11.006
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