Simulation of isometric muscle contraction in children with cerebral palsy

• Published in: Gait & posture Vol. 106; p. S345
• Main Authors: Madadi, Sadegh, Rostami, Mostafa, Posti, Mohadeseh
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2023
• ISSN: 0966-6362; 1879-2219
• DOI: 10.1016/j.gaitpost.2023.07.144

Identifying these changes will be very effective for providing more efficient treatment methods. Hill (1938) worked on the heat production of frog skeletal muscle, which introduced Hill's muscle model to describe skeletal muscle behavior. [1]. Huxley (1957) developed another model to describe muscle contraction, which later became more complex and precise. The total force produced by the muscle is equal to the sum of all the forces produced by the cross bridges [2]. Andrew Beuner et al. (2014) examined different Hill models to predict muscle performance in different conditions such as isometric force and changes in force and velocity during muscle response to stimulation [3]. Daniel Hafel et al. (2014) presented the Hill-type muscle model with four Germans [4]. How does isometric muscle contraction differ between children with cerebral palsy and healthy children, and can a simulation model help to better understand these differences? Subjects in the age group of 10.42 ± 1.28 and height 131.5 ± 2.94 participated in two healthy and cerebral palsy groups.We used marker trajectories from an extended marker set, based upon the Plug-in-Gait (PiG) model, to scale a generic 23 degree-of-freedom and 92 musculoskeletal actuator model in OpenSim version 4.2. We used inverse kinematics and Kinetic to calculate joint angles,moments by minimizing the error between the experimental markers and virtual model markers. The results of the data obtained from the simulation are presented in Opensim software. The information obtained from the software is analyzed by SPSS v.26 software with ANOVA. In all force model, significant differences were observed between the healthy and patient groups(P-value<0.001). [Display omitted] Medial Gastrocnemius Right Children with spastic cerebral palsy had shorter fascicles and muscles and longer Achilles tendons than normal children and it was observed that these muscles are constantly active in children with cerebral palsy due to the ankle being in plantar flexion. Statistical analyzes showed that the activation of the gastrocnemius muscle in isometric mode and the isometric force in the gastrocnemius muscle in children with cerebral palsy are far less and have a significant difference compared to healthy and growing children, one of the main reasons is that children with cerebral palsy The angles of the ankle joint are equinus, and the toe is in contact with the ground more than the heel, and they do not have a fixed muscle length, which can be used to examine the results of this research in more samples and subsequent tests.