Recent studies show that asymmetric movements are important Low Back Disorders risk factors. Measuring the trunk strength and identifying the coupling effects in different postures can provide an objective tool to assess one’s task capacity. This paper estimates the maximum performance capacity for isometric trunk extension and accompanying torques. Thirty males performed maximum voluntary isometric extension in 33 trunk postures on Sharif Lumbar Isometric Strength Tester device. Corresponding moments and angular positions were collected. Second-order full response surface models (RSM) were exploited to formulate the relationship between strengths and three trunk angles. The results of correlation coefficient, percent of standard estimation error and lack of fit reflected the adequacy of models. In conclusion, the main torque was the extension, but at the same time lateral bending and rotation torques were observed. For predicting these three torques in a specific posture and injury prevention, the second order RSM is a useful tool. The presented models can be used in the fields of ergonomics, occupational biomechanics and sport.
KatzJN. Lumbar disc disorders and low-back pain: socioeconomic factors and consequences. J Bone Joint Surg2006; 88: 21–24.
2.
MousaviSJAkbariMEMehdianH, et al. Low back pain in Iran: a growing need to adapt and implement evidence-based practice in developing countries. Spine2011; 36: E638–E46.
3.
DaneauCTétreauCDerocheT, et al. Impact of load expectations on neuromuscular and postural strategies during a freestyle lifting task in individuals with and without chronic low back pain. PLoS One2021; 16: e0246791.
4.
IhlebaekCHanssonTHLaerumE, et al. Prevalence of low back pain and sickness absence: a “borderline” study in Norway and Sweden. Scand J Public Health2006; 34: 555–558.
5.
ManchikantiL. Epidemiology of low back pain. Pain Physician2000; 2;3: 167–192.
6.
SchneiderSMohnenSMSchiltenwolfM, et al. Comorbidity of low back pain: representative outcomes of a national health study in the Federal Republic of Germany. Eur J Pain2007; 11: 387–397.
7.
MooreRMaoYZhangJ, et al. Economic burden of illness in Canada. Chronic Dis Inj Can1993; 18: 1.
8.
FrymoyerJWCats-BarilWL. An overview of the incidences and costs of low back pain. Orthop Clin North Am1991; 22: 263–271.
9.
MazloumiAKazemiZAbedZadehS, et al. Design and fabrication of portable motion recorder: comparing lumbar kinematics in workers with and without low back pain in assembly line of a car manufacturing industry. JHSW2021; 11: 55–71.
10.
ParnianpourMTanJ. Objective quantification of trunk performance. In: D’OrazioB (ed.) Back pain rehabilitation symposium on idiopathic low backpain. St Louis: Mosby, 1993. pp.205–237.
11.
SadeghiMShadmehrABagheriH, et al. Movement pattern & motor output during resisted trunk three dimensional motion. J Mod Rehabil2009; 3: 21–27.
12.
HadizadehMMousaviSJSedaghatnejadE, et al. The effect of chronic low back pain on trunk accuracy in a multidirectional isometric tracking task. Spine2014; 39: E1608–E15.
13.
MousaviSJOlyaeiGRTalebianS, et al. The effect of angle and level of exertion on trunk neuromuscular performance during multidirectional isometric activities. Spine2009; 34: E170–E7.
14.
TalebianSMousaviSJOlyaeiGR, et al. The effect of exertion level on activation patterns and variability of trunk muscles during multidirectional isometric activities in upright posture. Spine2010; 35: E443–E51.
15.
ArjmandNShirazi-AdlA. Biomechanics of changes in lumbar posture in static lifting. Spine2005; 30: 2637–2648.
16.
SheikhzadehAParnianpourMNordinM. Capability and recruitment patterns of trunk during isometric uniaxial and biaxial upright exertion. Clin Biomech2008; 23: 527–535.
17.
LavenderSAChenI-HTrafimowJ, et al. The effects of lateral trunk bending on muscle recruitments when resisting nonsagittally symmetric bending moments. Spine1995; 20: 184–190.
18.
SzpalskiMParnianpourM. Trunk performance, strength and endurance: measurement techniques and applications. Lumbar Spine1996; 2: 1074–1105.
19.
MohapatraSVermaAGirishN. Lifting capacity prediction model using physical performance measures among construction workers. Sci Rep2022; 12: 1–7.
20.
GolkhouVLucasCParnianpourM. Application of actor-critic reinforcement learning method for conrol of a sagittal arm during oscillatory movement. Biomed Eng2004; 16: 305–312.
21.
Zeinali-DavaraniSHemamiHBarinK, et al. Dynamic stability of spine using stability-based optimization and muscle spindle reflex. IEEE Trans Neural Syst Rehabil Eng2008; 16: 106–118.
22.
Zeinali-DavaraniSShirazi-AdlADariushB, et al. The effect of resistance level and stability demands on recruitment patterns and internal loading of spine in dynamic flexion and extension using a simple trunk model. Comput Methods Biomech Biomed Eng2011; 14: 645–656.
23.
RashediEKhalafKNassajianMR, et al. How does the central nervous system address the kinetic redundancy in the lumbar spine? Three-dimensional isometric exertions with 18 hill-model-based muscle fascicles at the L4—L5 level. Proc IMechE, Part H: J Engineering in Medicine2010; 224: 487–501.
24.
ShahvarpourAPourtakdoustHVossoughiGR, et al. Muscles force patterns prediction and joint reactions determination during 3D spine movements by means of optimal control theory. In: 2008 international conference on control, automation and systems, 2008, pp.548–553.
25.
ZamanRXiangYCruzJ, et al. Three-dimensional asymmetric maximum weight lifting prediction considering dynamic joint strength. Proc IMechE, Part H: J Engineering in Medicine2021; 235: 437–446.
26.
KhalafKAParnianpourM. A normative database of isokinetic upper-extremity joint strengths: towards the evaluation of dynamic human performance. Biomed Eng2001; 13: 79–92.
27.
KhalafKAParnianpourMSpartoPJ, et al. Modeling of functional trunk muscle performance: Interfacing ergonomics and spine rehabilitation in response to the ADA. J Rehabil Res Dev1997; 34: 459–469.
28.
KhalafKAParnianpourMKarakostasT. Surface response of isokinetic lower-extremity joint strength: towards the evaluation of Dynamic Human Performance. ASME1998; 39: 197–198.
29.
ParnianpourMNordinMKahanovitzN, et al. 1988 Volvo award in biomechanics. The triaxial coupling of torque generation of trunk muscles during isometric exertions and the effect of fatiguing isoinertial movements on the motor output and movement patterns. Spine1988; 13: 982–992.
30.
AzghaniMRFarahmandFMeghdariA, et al. Design and evaluation of a novel triaxial isometric trunk muscle strength measurement system. Proc IMechE, Part H: J Engineering in Medicine2009; 223: 755–766.
31.
MontgomeryDC. Design and analysis of experiment. Arizona: John Wiley & Sons Inc, 2005.
32.
RossECParnianpourMMartinD. The effects of resistance level on muscle coordination patterns and movement profile during trunk extension. Spine1993; 18: 1829–1838.
NordinMOrtengrenRAnderssonGB. Measurements of trunk movements during work. Spine1984; 9: 465–469.
35.
FathallahFAMarrasWSParnianpourM. The role of complex, simultaneous trunk motions in the risk of occupation-related low back disorders. Spine1998; 23: 1035–1042.
36.
TanJCParnianpourMNordinM, et al. Isometric maximal and submaximal trunk extension at different flexed positions in standing. Triaxial torque output and EMG. Spine1993; 18: 2480–2490.
37.
MarrasWSKingAIJoyntRL. Measurement of loads on the lumbar spine under isometric and isokinetic conditions. Spine1984; 9: 176–187.
38.
JonssonB. Muscular fatigue and endurance basic research and ergonomic applications. In KumamotoM. (ed.) Neural and mechanical control of movement. Yamaguchi Shoten: Kyoto, 1984, pp.64–76.
39.
KahnJFMonodH. Fatigue induced by static work. Ergonomics1989; 32: 839–846.
40.
MiedemaMCDouwesMDulJ. Recommended maximum holding times for prevention of discomfort of static standing postures. Int J Ind Ergon1997; 19: 9–18.
41.
ImbeauDFarbosB. Percentile values for determining maximum endurance times for static muscular work. Int J Ind Ergon2006; 36: 99–108.
42.
PriceAD. Calculating relaxation allowances for construction operatives - part 2: local muscle fatigue. Appl Ergon1990; 21: 318–324.
43.
RohmertW. Problems of determination of rest allowances part 2: determining rest allowances in different human tasks. Appl Ergon1973; 4: 158–162.
44.
RoseLEricssonMGlimskarB, et al. Development of a model to determine pause needs after fatigue and pain reactions during work. In Computer applications in ergonomics, occupational safety and health, 1992, pp.461–468.
45.
BuchalterDParnianpourMViolaK, et al. Three-dimensional spinal motion measurements. Part 1: A technique for examining posture and functional spinal motion. J Spinal Disord1988; 1: 279–283.
46.
PearcyMPortekIShepherdJ. Three-dimensional x-ray analysis of normal movement in the lumbar spine. Spine1984; 9: 294–297.
47.
PanjabiMYamamotoIOxlandT, et al. How does posture affect coupling in the lumbar spine?Spine1989; 14: 1002–1011.
48.
WeitzEM. The lateral bending sign. Spine1981; 6: 388–397.
49.
DumasGAPoulinMJRoyB, et al. A three-dimensional digitization method to measure trunk muscle lines of action. Spine1988; 13: 532–541.
50.
MacintoshJEBogdukN. The biomechanics of the lumbar multifidus. Clin Biomech1986; 1: 205–213.
51.
ParnianpourM.Applications of quantitative assessment of human performance in occupational medicine. In BronzinoJ. D. (ed.), Biomedical engineering fundamentals. Boca Raton, FL: CRC Press, 2006, pp. 83–117
