Wearable Ankle Assistance to Improve Walking Economy in Children with Cerebral Palsy

项目概要/摘要 儿童有效行走的能力对他们的身体健康和整体福祉至关重要。不幸的是， 许多患有脑性瘫痪（CP）的儿童，最常见的儿科身体残疾的原因， 行走和完成平衡密集的负重任务。这导致儿童与CP从事水平 的习惯性身体活动，远远低于指导方针和那些没有残疾的儿童，这反过来， 导致许多继发性疾病，包括代谢功能障碍和心血管疾病。的 CP引起的病理性步态模式和稳定性降低部分是由于踝关节功能减弱 足底和背屈肌步行的能量消耗与运动量呈负相关， CP儿童累积的身体活动强调了需要新的策略来大幅改善 在这个人群中行走的经济。为了实现这一目标，我们的建议旨在评估新的使用动力 来自可穿戴外骨骼的踝关节辅助，以改善患有 CP.第一个具体目标是量化动力足底屈肌辅助的幅度如何影响 以自选速度在地面上行走的能量学和力学，以设定速度在跑步机上行走，以及 在CP中以恒定速率步进。据推测，将确定最佳援助水平， 每项任务，最大限度地改善能源成本的运输，姿势，和积极的踝关节力量相比， 在无人辅助的情况下行走。第二个具体目标是评估训练频率和患者 特征影响重复地上行走过程中的临床和生物力学步态结果 在CP中使用动力踝关节辅助。将随机选择患有CP步态缺陷的个体， 30分钟的地面步态训练，每周2次，持续4周，或 每周4次，持续2周。步行的经济性和速度将在比赛开始、中间和结束时进行评估。 培训期间。据推测，较高频率的训练和总动力步行时间将是积极的 与步态结局相关，而GMFCS水平和痉挛严重程度与步态结局呈负相关 成果。从该建议中获得的基本知识将导致安全和有效的控制 CP儿童在地上和楼梯行走期间动力足底屈肌辅助的参数，以及 提供有关培训和参与者特征的见解，可以为未来干预研究的设计提供信息。 通过支持学生的研究参与，这个学术研究促进奖将有助于成长 我们在北方亚利桑那大学的生物工程和生物工程博士课程的新中心。

PROJECT SUMMARY/ABSTRACT The ability of children to walk effectively is essential to their physical health and general well-being. Unfortunately, many children with cerebral palsy (CP), the most common cause of pediatric physical disability, have difficulty walking and completing balance-intensive weight-bearing tasks. This leads to children with CP engaging in levels of habitual physical activity that are well below guidelines and those of children without disabilities, which in turn contributes to many secondary conditions, including metabolic dysfunction and cardiovascular disease. The pathological gait patterns and reduced stability caused by CP are due, in part, to diminished function of the ankle plantar- and dorsi-flexor muscles. The negative relationship between the energy cost of walking and amount of accumulated physical activity in children with CP underscores the need for new strategies to drastically improve walking economy in this population. To meet this goal, our proposal aims to evaluate the novel use of powered ankle assistance from a wearable exoskeleton to improve walking economy across varied terrain in children with CP. The first specific aim is to quantify how the magnitude of powered plantar-flexor assistance affects the energetics and mechanics of over-ground walking at self-selected speeds, treadmill walking at set speeds, and stair stepping at a constant rate in CP. It is hypothesized that an optimal level of assistance will be identified for each task that maximizes improvements in energy cost of transport, posture, and positive ankle power compared to unassisted walking conditions. The second specific aim is to evaluate how training frequency and patient characteristics affect clinical and biomechanical gait outcomes across repeated over-ground walking sessions with powered ankle assistance in CP. Individuals with gait deficits from CP will be randomly selected to complete 30 minutes of over-ground gait training with individually-tuned plantar-flexor assistance 2x/week for 4 weeks or 4x/week for 2 weeks. Walking economy and speed will be assessed at the beginning, middle, and end of the training period. It is hypothesized that higher frequency training and total powered walking time will be positively associated with gait outcomes, while GMFCS level and spasticity severity will be negatively associated with gait outcomes. The fundamental knowledge gained from this proposal will result in safe and effective control parameters for powered plantar-flexor assistance during over-ground and stair walking in children with CP, and provide insight on training and participant characteristics that can inform the design of future intervention studies. Through supporting student research involvement, this Academic Research Enhancement Award will help grow our new Center for Bioengineering and Bioengineering PhD program at Northern Arizona University.