HEИндивидуална стипендия2022–2024

simSpas · Development of a simulation platform to study the role of joint hyper-resistance in functional tasks in children with cerebral palsy.

„Хоризонт Европа“ — Действия „Мария Склодовска-Кюри“

Период: 2022-10-01 → 2024-09-30
Финансиране от ЕС: 191 760 €
Участници: 1
Схема: HORIZON-TMA-MSCA-PF-EF

Линиите свързват координатора с партньорите.

Накратко на български

Симулационни модели анализират как конкретни мускулни и скелетни проблеми влияят върху походката при деца с церебрален парализа. Това помага за по-доброто разбиране на механизмите на движението и по-точното планиране на лечението за всеки пациент.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

Development of a simulation platform to study the role of joint hyper-resistance in functional tasks in children with cerebral palsy.

In this project, we developed simulation methods that can be used to help understand the underlying mechanics of movement disorders in children with cerebral palsy, and to aid treatment planning. Children with cerebral palsy suffer from multiple neuro-musculoskeletal deficits like decreased muscle selectivity, increased spinal reflex, increased muscle tone and skeletal deformities that cause gait deficits. Moreover, there is a big diversity in the presence and intensity of each deficit in different affected children, making it hard to study the underlying mechanics of individual deficits only using experiments. Indeed, the success rates of surgeries in children with cerebral palsy have not improved in the last 15 years. Recently developed state-of-the-art musculoskeletal modelling and simulations can help us understand the role of individual deficits and their interaction on gait deficits as we can develop physics-based models of each deficit and study their effect on movement in isolation and in presence of specific deficits. The same simulations can then be used to study the effect of addressing deficits in isolation and/or in combination to aid treatment planning. In this project, we improved the accuracy of the musculoskeletal model personalization that will improve the accuracy what we learn from musculoskeletal modelling and simulation studies and the accuracy of proposed treatment planning. Additionally, this project contributed towards making the state-of-the-art musculoskeletal modelling and simulations platform easy to use. An open source software called PredSim was created that can be used not only for studying children with cerebral palsy, but also human gait and running, disorders like stroke, Duchenne muscular dystrophy, walking with prosthesis, and even animal and bird locomotion. Additionally, in this project, we also developed tools to study certain underlying mechanics in children with cerebral palsy that cannot be studied using PredSim. Sensory signals and motor commands are corrupted by errors called sensorimotor noise. A heightened gastrocnemius activity at heel-strike has been observed in children with cerebral palsy, and it has been theorized that the reason for this high gastrocnemius activity could be the presence of high sensorimotor noise and/or the interaction of sensorimotor noise with other deficits in children with cerebral palsy. Since PredSim does not account for sensorimotor noise, it is not able to predict the observed heightened gastrocnemius activity. Accounting for sensorimotor noise along with a complex control policy in simulations is computationally very expensive, and for that reason, most simulation generating platforms do not account for it. This limitation was recently addressed by prof. dr. Friedl De Groote. They developed a simulation platform that could generate simulations of walking while accounting for sensorimotor noise. This platform, however, used a simple stick figure human model without any feet or muscles. To study the role of sensorimotor noise, and its interaction with other deficits during gastrocnemius activity at heel-strike, the fellowship recipient added feet and muscles to the simulation platform that accounts for sensorimotor noise. These developments will enable researchers to study isolated an interaction effects of sensorimotor noise in children with cerebral palsy.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

Joint hyper-resistance to movement affects 85% of children with cerebral palsy (CP), the most common cause of physical disability in children. Joint hyper-resistance is an important treatment target in CP. Yet, its contribution to gait and balance impairments is poorly understood because it has been hard to associate clinical test outcomes to gait and balance deficits. Here, we will test a novel hypothesis about the mechanisms underlying joint hyper-resistance. We hypothesize that the neural component of joint hyper-resistance results from movement history-dependent muscle mechanics and its interaction with background muscle activity and hyperactive reflexes. The movement history-dependent muscle force response to stretch, which drives spindle firing and reflex activity, might explain why it has been so hard to relate clinical test outcomes to functional impairments. Indeed, movement history might be very different when walking than when relaxing during a clinical test. However, it is unfeasible to measure muscle and spindle responses to stretch non-invasively. Hence, we will use computer simulations to test whether the proposed mechanism can explain the response to stretch in clinical tests, during perturbed standing balance, and during walking. This requires two extensions to existing simulation frameworks. First, we will integrate more mechanistic muscle models in whole body simulations of movement as the commonly used phenomenological Hill models do not accurately capture the response to stretch. Second, we will account for uncertainty due to sensorimotor noise when simulating whole body movement as such uncertainty might trigger muscle stretch and maladaptive responses. I will build on my own and the hosts experience to realize these computationally challenging modeling developments. This project might improve the diagnosis and treatment of joint hyper-resistance in CP and has thereby the potential to improve the quality of life of many individuals with CP.

Оригинален текст от CORDIS (на английски).

Участници

KATHOLIEKE UNIVERSITEIT LEUVEN · LeuvenКоординаторБелгия