A new method for muscle fatigue assessment: Online model identification techniques

• Published in: Muscle & nerve Vol. 50; no. 4; pp. 556 - 563
• Main Authors: Papaiordanidou, Maria, Hayashibe, Mitsuhiro, Varray, Alain, Fattal, Charles, Guiraud, David
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.10.2014; Wiley Subscription Services, Inc; Wiley
• Subjects: Adult; Analysis of Variance; Automatic Control Engineering; Computer Science; contractile apparatus; Electric Stimulation - adverse effects; Evoked Potentials, Motor - physiology; Humans; identification method; Middle Aged; Models, Biological; Muscle Contraction - physiology; Muscle Fatigue - physiology; muscle model; Online Systems; paraplegia; Paresis - diagnosis; Paresis - etiology; Sigma-Point Kalman Filter; Spinal Cord Injuries - complications; Torque; identification method; Sigma-Point Kalman Filter; muscle model; paraplegia; contractile apparatus
• ISSN: 0148-639X; 1097-4598; 1097-4598
• DOI: 10.1002/mus.24190

ABSTRACT Introduction: The purpose of this study was to propose a method that allows extraction of the current muscle state under electrically induced fatigue. Methods: The triceps surae muscle of 5 subjects paralyzed by spinal cord injury was fatigued by intermittent electrical stimulation (5 × 5 trains at 30 Hz). Classical fatigue indices representing muscle contractile properties [peak twitch (Pt) and half‐relaxation time (HRT)] were assessed before and after each 5‐train series and were used to identify 2 relevant parameters (Fm, Ur) of a previously developed mathematical model using the Sigma‐Point Kalman Filter. Results: Pt declined significantly during the protocol, whereas HRT remained unchanged. Identification of the model parameters with experimental data yielded a model‐based fatigue assessment that gave a more stable evaluation of fatigue than classical parameters. Conclusions: This work reinforces clinical research by providing a tool that clinicians can use to monitor fatigue development during stimulation. Muscle Nerve 50: 556–563, 2014