Improving mobility in peripheral artery disease using an ankle foot orthosis

外周动脉疾病（PAD）是系统性动脉粥样硬化的表现， 以动脉粥样硬化阻塞腿部动脉为特征。 跛行被定义为步行引起的步态功能障碍和肌肉疼痛，是最常见的 PAD的常见表现。跛行影响5%的55岁以上的美国人 岁的跛行患者的活动能力降低， 功能障碍、健康状况不佳以及福尔斯跌倒风险增加。在我们的研究 实验室已经记录了踝跖屈肌的显著缺陷， 行走时的正常扭矩和功率。此外，PAD患者的受累腿部 表现出阻止正常肌肉功能的肌肉肌病。在监督下 运动对于增加PAD患者的步行距离是有效的， 产生踝跖屈肌扭矩，或减少腿部肌肉的压力。脚踝- 足矫形器（AFO）是一种由碳纤维复合材料制成的可补偿踝关节的装置 跖屈肌扭矩和功率，并降低血流量需求和肌肉应力 在走路的时候。碳复合材料AFO的弹簧特性允许能量 在重量验收时储存，并在脚趾离开点返回。我们的试点工作表明， 戴着AFO走路会立即增加初始和绝对步行量， 与药物治疗6个月的PAD患者的距离一样多。本研究 将确定AFO是否能改善PAD患者的行走能力， 第一次使用。此外，该研究将测试三个月AFO后的行走性能 我们将研究这种AFO干预的可行性。中央 一种假设是，AFO通过降低 步行的能量消耗。三个月后的行走性能改善 由于改善了肌肉组织， 患者患肢的功能。有关机制的详细措施 步行表现，肌肉贡献，身体活动，生活质量以及这些 佩戴AFO三个月后的机制变化将提供证据 需要实施AFO治疗，这将改善功能状态和质量， PAD患者的生活。

Peripheral artery disease (PAD) is a manifestation of systemic atherosclerosis, characterized by atherosclerotic blockages of the arteries supplying the legs. Claudication, defined as walking induced gait dysfunction and muscle pain, is the most common manifestation of PAD. Claudication affects 5% of Americans older than 55 years of age. Claudicating patients experience reduced mobility, reduced physical functioning, poor health outcomes, and increased risk for falls. Research in our laboratory has documented significant deficits in the ankle plantarflexors to generate normal torque and power during walking. Further, affected legs of patients with PAD demonstrate a muscle myopathy that prevents normal muscle function. While supervised exercise is effective for increasing the distance patients with PAD can walk, it does not generate ankle plantarflexor torque, or decrease stress on the leg muscles. An ankle- foot orthosis (AFO) is a device made of carbon-composite material that can offset ankle plantarflexor torque and power and decrease blood flow demand and muscular stress during walking. The spring-like properties of carbon composite AFOs allow energy storage at weight acceptance and return at the point of toe off. Our pilot work has shown that walking with an AFO immediately increases the initial and absolute walking distances in patients with PAD as much as pharmacotherapy for six months. This study will determine whether an AFO improves walking performance in patients with PAD from its first use. Additionally, the study will test walking performance after a three month AFO intervention and will examine the feasibility of this AFO intervention. The central hypothesis is that the AFO immediately improves walking performance by decreasing the energy cost of walking. Walking performance improvement following the three-month intervention is expected to be larger than that of first use due to improving the muscular function of patients' affected legs. Detailed measures of mechanisms related with walking performance, muscle contribution, physical activity, quality of life and how these mechanisms change after wearing the AFO for three months will provide the evidence required to implement an AFO therapy that will improve functional status and quality of life in individuals with PAD.