title: Methodology to Customize Maximal Isometric Forces for Hill-Type Muscle Models.
abstract: One approach to increasing the confidence of muscle force estimation via musculoskeletal models is to minimize the root mean square error (RMSE) between joint torques estimated from electromyographic-driven musculoskeletal models and those computed using inverse dynamics. We propose a method that reduces RMSE by selecting subsets of combinations of maximal voluntary isometric contraction (MVIC) trials that minimize RMSE. Twelve participants performed 3 elbow MVIC in flexion and in extension. An upper-limb electromyographic-driven musculoskeletal model was created to optimize maximum muscle stress and estimate the maximal isometric force of the biceps brachii, brachialis, brachioradialis, and triceps brachii. Maximal isometric forces were computed from all possible combinations of flexion-extension trials. The combinations producing the smallest RMSE significantly reduced the normalized RMSE to 7.4% compared with the combination containing all trials (9.0%). Maximal isometric forces ranged between 114-806 N, 64-409 N, 236-1511 N, and 556-3434 N for the brachii, brachialis, brachioradialis, and triceps brachii, respectively. These large variations suggest that customization is required to reduce the difference between models and actual participants' maximal isometric force. While the smallest previously reported RMSE was 10.3%, the proposed method reduced the RMSE to 7.4%, which may increase the confidence of muscle force estimation.
authors.affiliation: 1 CHU Ste Justine.|2 Université de Montréal.
authors.forename: Fabien
authors.initials: F
authors.lastname: Dal Maso
authors.affiliation: 1 CHU Ste Justine.|2 Université de Montréal.
authors.forename: Mickaël
authors.initials: M
authors.lastname: Begon
authors.affiliation: 1 CHU Ste Justine.
authors.forename: Maxime
authors.initials: M
authors.lastname: Raison
mesh_terms: D000328:Adult; D000465:Algorithms; D003198:Computer Simulation; D004551:Elbow Joint / Q000502:physiology*; D004576:Electromyography / Q000379:methods*; D056966:Excitation Contraction Coupling / Q000502:physiology; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D018482:Muscle, Skeletal / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical
keywords: antagonist muscles; best combination; electromyography; maximum muscle stress; musculoskeletal model; numerical optimization