Highly repetitive motion is associated with development of upper extremity musculoskeletal disorders (UEMSDs) among industrial workers, especially when encountered concurrently with forceful exertions. Current measures of “repetitiveness” provide information about the repetitiveness of joint motion, but fail to provide complete information about the repetitiveness of muscular exertion, a more biomechanically meaningful measure of repetition. The current study introduces a novel processing technique in which surface electromyography (sEMG) data is root-mean-square processed prior to computation of the frequency spectrum. The mean power frequency of the resulting power spectrum is the proposed metric for estimation of muscular exertion frequency. The metric was compared to joint movement and applied force frequencies during a series of isometric gripping trials and an industrial simulation. Results suggest that the proposed metric has potential to be a valuable metric to estimate exposure to repetitive muscular exertion.
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References
1.
BuchholzB.WellmanH. (1997). Practical operation of a biaxial goniometer at the wrist joing. Human Factors, 39(1), 119-129.
2.
Bureau of Labor Statistics. (2010). Nonfatal occupational injuries and illnesses requiring days away from work, 2009. BLS, US Department of Labor, May9, 2010.
3.
CabeçasJ. (2007). The risk of distal upper limb disorder in cleaners: A modified application of the Strain Index method. International Jounal of Industrial Ergonomics, 37, 563-571.
4.
ChaffinD.AndersonG.MartinB. (1999). In Wiley & Sons I. (Ed.), Occupational Biomechanics, Third Edition. New York, NY:
5.
ChiangH.KoY.ChenS.YuH.WuT.ChangP. (1993). Prevalence of shoulder and upper-limb disorders among workers in the fish-processing industry. Scandinavian Jounal of Work, Environment, & Health, 19(2), 126-131.
6.
CramJ.KasmanG. (1998). Introduction to surface electromyography. Maryland: Aspen Publishers.
7.
EbersoleM.ArmstrongT. (2006). Analysis of an observational rating scale for repetition, posture, and force in selected manufacturing settings. Human Factors, 48(3), 487-498.
8.
GerrF.LetzR.LandriganP. (1991). Upper-extremity musculoskeletal disorders of occupational origin. Annual Review of Public Health, 12, 543-566.
9.
JonssonB. (1982). Measurement and evaluation of local muscular strain in the shoulder during constrained work. Journal of Human Ergology, 11, 73-88.
10.
Juul-KristensenB.FallentinN.HanssonG.MadeleineP.AndersonJ.EkdahlC. (2002). Physical workload during manual and mechanical deboning of poultry. International Journal of Industrial Ergnomics, 29, 107-115.
11.
KetolaR.ToivonenR.Viikari-JunturaE. (2001). Interobserver repeatability and validity of an observation method to assess physical loads imposed on the upper extremities. Ergonomics, 44, 119-313.
12.
LatkoW.ArmstrongT.FoulkeJ.HerrinG.RaboumR.UlinS. (1997). Development of an observational method for assessing repetition in hand tasks. American Industrial Hygiene Association Journal, 58, 278-285.
13.
MalchaireJ.CockN.PietteA.LeaoD.LaraM.AmaralF. (1997). Relationship between work constraints and the development of musculoskeletal disorders of the wrist: A prospective study. International Jounal of Industrial Ergonomics, 19, 471-482.
14.
MayerT.GatchelR.PolatinP.EvansT. (1999). Outcomes comparison of treatment for chronic disabling work-related upper-extremity disorders and spinal disorders. Journal of Occupational and Environmental Medicine, 41(9), 761-770.
15.
MooreJ.GargA. (1995). The Strain Index: a proposed method to analyze jobs for risk of distal upper extremity disorders. American Industrial Hygiene Association Journal, 56(5), 443-459.
16.
RadwinR.LinM. (1993). An analytical method for characterizing repetitive motion and postural stress using spectral analysis. Ergonomics, 36(4), 379-389.
17.
SilversteinB.FineL.ArmstrongT. (1987). Occupational factors and carpal tunnel syndrome. American Journal of Industrial Medicine, 11(3), 343-358.
18.
SpielholzP.SilversteinB.MorganM.CheckowayH.KaufmanJ. (2001). Comparison of self-report, video observation and direct measurement methods for upper extremity musculoskeletal disorder physical risk factors. Ergonomics, 44(6), 588-613.
19.
StockS. (1991). Workplace ergonomic factors and the development of musculoskeletal disorders of the neck and upper limbs: A meta-analysis. American Journal of Industrial Medicine, 19, 87-107.
20.
ThornS.SøgaardK.KallenbergL.SandsjöL.SjøgaardG.HermensH.. (2007). Trapezius muscle rest time during standardised computer work - A comparison of female computer users with and without self-reported neck/shoulder complaints. Journal of Electromyography and Kinesiology, 17, 420-427.
21.
Viikari-JunturaE.RauasS.MarikainenR.KuosmaE.RiihimäkiH.TakalaE.SaarenmaaK. (1996). Validity of self-reported physical work load in epidemiologic studies on musculoskeletal disorders. Scandinavian Jounal of Work, Environment, & Health, 22, 251-259.
22.
WurzelbacherS.BurtS.CrombieK.RamseyJ.LouL.AlleeS.JinY. (2010). A comparison of assessment methods of hand activity and force for use in calculating the ACGIH(R) Hand Activity Level (HAL) TLV(R). Journal of Occupational and Environmental Hygiene, 7, 407-416.
23.
ZippP. (1982). Recommendations for the standardization of lead positions in surface electromyography. European Journal of Applied Physiology and Occupational Physilogy, 50, 41-54.
