Identification of dynamic myoelectric signal-to-force models during isometric lumbar muscle contractions

Thelen, Darryl G.; Schultz, Albert B.; Fassois, Spilios D.; Ashton-Miller, James A.

Affiliations

¹Biomechanics Research Laboratory, Department of Mechanical Engineering and Applied Mechanics, University of Michigan, Ann Arbor, Michigan, U.S.A.

Abstract

A 14-muscle myoelectric signal (MES)-driven muscle force prediction model of the L3-L4 cross section is developed which includes a dynamic MES-force relationship and allows for cocontraction. Model parameters are estimated from MES and moments data recorded during rapid exertions in trunk flexion, extension, lateral bending and axial twist. Nine young healthy males participated in the experimental testing. The model used in the parameter estimation is of the output error type. Consistent and physically feasible parameter estimates were obtained by normalizing the RMS MES to maximum exertion levels and using nonlinear constrained optimization to minimize a cost function consisting of the trace of the output error covariance matrix. Model performance was evaluated by comparing measured and MES-predicted moments over a series of slow and rapid exertions. Moment prediction errors were on the order of 25, 30 and 40% during attempted trunk flexion-extensions, lateral bends and axial twists, respectively. The model and parameter estimation methods developed provide a means to estimate lumbar muscle and spine loads, as well as to empirically investigate the use and effects of cocontraction during physical task performances.

Links

DOI: 10.1016/0021-9290(94)90263-1

PubMed: 8063841

WoS: A1994NQ27000005

History

Revised: 1993-09-23

Cited Works (6)

Year	Entry
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Cited By (14)

Year	Entry
2007	Erdemir A, McLean S, Herzog W, van den Bogert AJ. Model-based estimation of muscle forces exerted during movements. Clin Biomech (Bristol, Avon). February 2007;22(2):131-154.
2004	Buchanan TS, Lloyd DG, Manal K, Besier TF. Neuromusculoskeletal modeling: estimation of muscle forces and joint moments and movements from measurements of neural command. J Appl Biomech. November 2004;20(4):367-395.
2003	Lloyd DG, Besier TF. An EMG-driven musculoskeletal model to estimate muscle forces and knee joint moments in vivo. J Biomech. June 2003;36(6):765-776.
2003	Manal K, Buchanan TS. A one-parameter neural activation to muscle activation model: estimating isometric joint moments from electromyograms. J Biomech. August 2003;36(8):1197-1202.
2009	Winby CR, Lloyd DG, Besier TF, Kirk TB. Muscle and external load contribution to knee joint contact loads during normal gait. J Biomech. October 16, 2009;42(14):2294-2300.
2015	Pizzolato C, Lloyd DG, Sartori M, Ceseracciu E, Besier TF, Fregly BJ, Reggiani M. CEINMS: a toolbox to investigate the influence of different neural control solutions on the prediction of muscle excitation and joint moments during dynamic motor tasks. J Biomech. November 5, 2015;48(14):3929-3936.
1996	Lloyd DG, Buchanan TS. A model of load sharing between muscles and soft tissues at the human knee during static tasks. J Biomech Eng. August 1996;118(3):367-376.
2008	Pal S. Explicit Finite Element Modeling of Joint Mechanics [PhD thesis]. University of Denver; August 2008.
2015	Saxby DJ. The Tibiofemoral Contact Forces in Human Anterior Cruciate Ligament Reconstructed and Healthy Knees and Their Association With Articular Tissue Degeneration [PhD thesis]. Brisbane, Australia: Griffith University; September 2015.
2016	Pizzolato C. Real-Time Estimation of Lower Limb Musculoskeletal Tissue Loading Using an Electromyogram-Informed Neuromusculoskeletal Model [PhD thesis]. Brisbane, Australia: Griffith University; April 2016.
1998	Sadouk S. Analyse mécanique par éléments finis du système actif-passif de la colonne lombaire humaine [Master's thesis]. École polytechnique de Montréal; October 1998.
2014	Newell R. Are Inversion, Posture, Motion and Muscle Effects Important to Spinal Alignment? [PhD thesis]. Vancouver, BC: University of British Columbia; April 2014.
2002	Lee T. Using an EMG-Driven Model to Predict Knee Joint Dynamics [Master's thesis]. University of Toronto; 2002.
2008	Brown SHM. Examining the Neuromuscular and Mechanical Characteristics of the Abdominal Musculature and Connective Tissues: Implications for Stiffening the Lumbar Spine [PhD thesis]. University of Waterloo; 2008.