title: Combined Ultrasound Imaging and Biomechanical Modeling to Estimate Triceps Brachii Musculotendon Changes in Stroke Survivors.
abstract: The aim of this study was to investigate the changes of musculotendon parameters of triceps brachii in persons after stroke based on subject-specific biomechanical modeling technique combined with in vivo ultrasound measurement. Five chronic stroke survivors and five normal control subjects were recruited. B-mode ultrasound was applied to measure muscle pennation angle and the optimal length of three heads of triceps' brachii at different joint angle positions in resting and isometric contraction. Measured ultrasound data were used to reduce the unknown parameters during the modeling optimization process. The results showed that pennation angles varied with joint angles, and the longhead TRI pennation from stroke group was smaller than the literature value. The maximum isometric muscle stress from persons after stroke was significantly smaller than that found in the unimpaired subjects. The prediction of joint torque fits well with the measured data from the control group, whereas the prediction error is larger in results from persons after stroke. In vivo parameters from ultrasound data could help to build a subject-specific biomechanical model of elbow extensor for both unimpaired and hemiplegic subjects, and then the results driven from the model could enhance the understanding of motor function changes for persons after stroke.
authors.affiliation: Department of Rehabilitation Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China; Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston and Research Center at TIRR Memorial Hermann Hospital, Houston, TX, USA.
authors.forename: Le
authors.identifier: 0000-0002-9340-9061
authors.initials: L
authors.lastname: Li
authors.affiliation: Biomedical Engineering Division, Department of Electronic Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong.
authors.forename: Raymond Kai-Yu
authors.initials: RK
authors.lastname: Tong
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D004551:Elbow Joint / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D020521:Stroke / Q000000981:diagnostic imaging* / Q000503:physiopathology; D000071939:Stroke Rehabilitation / Q000379:methods; D017741:Survivors; D013710:Tendons / Q000503:physiopathology; D014463:Ultrasonography