Veerkamp Kirsten, Carty Christopher P, Waterval Niels F J, Geijtenbeek Thomas, Buizer Annemieke I, Lloyd David G, Harlaar Jaap, van der Krogt Marjolein M
Department of Rehabilitation Medicine, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam,The Netherlands.
Rehabilitation & Development, Amsterdam Movement Sciences, Amsterdam,The Netherlands.
J Appl Biomech. 2023 Aug 2;39(5):334-346. doi: 10.1123/jab.2023-0022. Print 2023 Oct 1.
Spasticity is a common impairment within pediatric neuromusculoskeletal disorders. How spasticity contributes to gait deviations is important for treatment selection. Our aim was to evaluate the pathophysiological mechanisms underlying gait deviations seen in children with spasticity, using predictive simulations. A cluster analysis was performed to extract distinct gait patterns from experimental gait data of 17 children with spasticity to be used as comparative validation data. A forward dynamic simulation framework was employed to predict gait with either velocity- or force-based hyperreflexia. This framework entailed a generic musculoskeletal model controlled by reflexes and supraspinal drive, governed by a multiobjective cost function. Hyperreflexia values were optimized to enable the simulated gait to best match experimental gait patterns. Three experimental gait patterns were extracted: (1) increased knee flexion, (2) increased ankle plantar flexion, and (3) increased knee flexion and ankle plantar flexion when compared with typical gait. Overall, velocity-based hyperreflexia outperformed force-based hyperreflexia. The first gait pattern could mostly be explained by rectus femoris and hamstrings velocity-based hyperreflexia, the second by gastrocnemius velocity-based hyperreflexia, and the third by gastrocnemius, soleus, and hamstrings velocity-based hyperreflexia. This study shows how velocity-based hyperreflexia from specific muscles contributes to different spastic gait patterns, which may help in providing targeted treatment.
痉挛是小儿神经肌肉骨骼疾病中常见的一种损伤。痉挛如何导致步态偏差对于治疗方案的选择至关重要。我们的目的是通过预测模拟来评估痉挛儿童步态偏差背后的病理生理机制。进行聚类分析以从17名痉挛儿童的实验步态数据中提取不同的步态模式，用作比较验证数据。采用正向动力学模拟框架来预测基于速度或力的反射亢进的步态。该框架包含一个由反射和脊髓上驱动控制的通用肌肉骨骼模型，由一个多目标成本函数支配。对反射亢进值进行优化，以使模拟步态与实验步态模式最佳匹配。提取了三种实验步态模式：（1）与典型步态相比，膝关节屈曲增加；（2）踝关节跖屈增加；（3）膝关节屈曲和踝关节跖屈增加。总体而言，基于速度的反射亢进优于基于力的反射亢进。第一种步态模式主要可以由股直肌和腘绳肌基于速度的反射亢进解释，第二种由腓肠肌基于速度的反射亢进解释，第三种由腓肠肌、比目鱼肌和腘绳肌基于速度的反射亢进解释。本研究展示了特定肌肉基于速度的反射亢进如何导致不同的痉挛步态模式，这可能有助于提供针对性的治疗。
