ZeroG: Dynamic Over-Ground Body-Weight Support System

描述（由申请人提供）：即使是最熟练的治疗师，成功地为有严重行走缺陷的个体提供强化且安全的步态治疗也是最大的挑战。在许多神经损伤的急性阶段，如中风、脊髓损伤或创伤性脑损伤，患者通常表现出高度不稳定的行走模式和较差的耐力，这使得患者和治疗师都很难安全地练习步态。正因为如此，康复中心大力推动将地面步态训练转移到跑步机上，在跑步机上，体重支持系统可以帮助减少跌倒，同时提高训练强度。许多研究已经调查了体重支持跑步机训练的有效性，并发现这种步态训练模式可以促进步行能力的提高，与传统的步态训练相似或更好。不幸的是，市场上的技术还没有将训练对象从跑步机上的训练过渡到安全的、有重量支撑的地面步态训练。练习在地面上行走是至关重要的，因为我们最近的研究已经证明了在跑步机上行走和在地面上行走之间的关键区别。由于所有行走障碍患者的主要目标是在家中和社区中行走，因此必须进行包括地面步态训练在内的治疗干预。在过去的三年里，我们一直在开发一种名为ZeroG的地面体重支持步态训练系统，该系统为有步态障碍的人在练习地面行走时提供他们体重的一定百分比的动态卸载。该系统沿着高架轨道运行，提供静态和动态卸载，并有一个主动小车，在受试者行走时自动跟随。在这里，一个小电机驱动系统，这样当他们在地面上行走时，它就会保持在被试的正上方。虽然现有的小车跟踪系统可以很好地适应行走速度慢的人的地面步态，但它的速度和所能提供的力量都是有限的。在小车上增加额外的力对于控制受试者在跌倒时的前进动量以及在将受试者从轮椅上抬起或从地板上抬起时的稳定是很重要的。此外，我们的长期目标是增加坐立协议以及动态平衡任务，这将需要额外的力量和手推车更好的性能。第一阶段SBIR的目标是用更大的电机改造ZeroG小车，并开发增强的控制算法，以改善受试者在地面步态中的跟踪，并可用于高级训练活动。在第一阶段开发的硬件和控制器将用于第二阶段的高级姿势和动态任务的开发。在SBIR的第一和第二阶段增强ZeroG的能力，将使下肢受损的个人能够练习地上步态，以及姿势和动态平衡任务，使其成为世界上最通用的步态训练系统之一。因此，我们相信，与现有的传统康复策略相比，使用ZeroG进行训练的个体将在地面行走能力方面获得更大的收益，因为ZeroG将允许治疗师在神经损伤后早期以安全、可控的方式对患者进行广泛的活动训练。该系统可用于各种残疾状况的功能康复，包括中风和脊髓损伤到截肢以及老年人。除了临床益处，这种性质的体重支持系统也可以用于促进新的研究，重点是步态障碍。公共卫生相关性：最近的研究报告称，仅在美国，就有超过18%的人口（或相当于3560万人）患有某种形式的行走障碍，这对他们在社区层面的行走能力产生了负面影响（DeJong et al., 2002）。行走障碍被定义为在没有支撑的情况下平衡、稳定性和耐力的缺陷，在中风、多发性硬化症（MS）、脑瘫（CP）、脊髓损伤（SCI）、截肢和与一般衰老相关的正常并发症之后的个体中很常见。不幸的是，由于人口老龄化，在未来几年里，行走困难的人数将继续增加。美国人口普查局预计，老年人口（65岁或以上）的规模将从1999年的3300多万（占美国人口的12.7%）增加到2020年的5300万，到2040年将增加到7700万（美国人口普查局，2001年）。这一趋势引起了很大的关注，因为超过一半的老年人（36.3%）有某种形式的平衡和步态障碍，而大约17.9%的老年人有严重的行走障碍（DeJong, 2002）。此外，美国中风协会（National Stroke Association）预计，在未来20年，美国公民中风患者的数量将超过每年100万，其中一半的中风幸存者将经历包括步态障碍在内的长期残疾（Stroke Association, 2008）。为什么这是一个重要的卫生保健问题？平衡控制缺陷和行走障碍往往导致个人在他们的直接环境之外感到不安全，使他们无法真正重新融入社会并充分参与社会。不幸的是，保健提供者对康复中心施加的经济压力严重阻碍了这些疾病的治疗。如今，康复中心治疗患者的时间比以往任何时候都少，1994年至2001年间，住院康复治疗的中位数时间从20天减少到12天，而骨科患者的住院时间比例减少最大（Ottenbacheret al., 2004）。这通常导致康复中心被迫让患者出院，即使他们在行走能力方面继续取得重大进展。这一统计数据令人不安的矛盾之处在于，在许多神经和肌肉骨骼疾病后，广泛的治疗会导致平衡控制和行走能力的显著恢复（Barbeauet al ., 1998）。这些改进通常允许这些人独立执行adl，在某些情况下，返回工作岗位。因此，治疗师必须有适当的工具来治疗高度受损受试者在受伤后早期和适当的强度的步态障碍。该系统将在本次SBIR中进一步开发和测试，将有助于解决众多受试者群体的行走障碍问题，允许治疗师和临床医生在恢复的早期阶段安全地治疗患者，这是影响步态结果的重要因素（Horn et al., 2005）。

DESCRIPTION (provided by applicant): Successfully delivering intensive yet safe gait therapy to individuals with significant walking deficits presents the greatest challenges to even the most skilled therapists. In the acute stages of many neurological injuries such as stroke, spinal cord injury, or traumatic brain injury, individuals often exhibit highly unstable walking patterns and poor endurance, making it difficult to safely practice gait for both the patient and therapist. Because of this, there has been a big push in rehabilitation centers to move over-ground gait training to the treadmill where body-weight support systems can help minimize falls while at the same time raising the intensity of the training. Numerous studies have investigated the effectiveness of body-weight supported treadmill training and have found that this mode of gait training promotes gains in walking ability similar to or greater than conventional gait training. Unfortunately there is a gap in technologies on the market for transitioning subjects from training on a treadmill to safe, weight-supported over-ground gait training. Practicing walking over-ground is critical, as our recent studies have demonstrated key differences between walking on a treadmill and walking over-ground. Since a primary goal of all individuals with walking impairments is to walk in their homes and in the community, it is imperative that therapeutic interventions involve over-ground gait training. Over the last three years, we have been developing an over-ground body-weight support gait training system called ZeroG, which provides individuals with gait impairments dynamic unloading of a percentage of their body-weight as they practice walking over-ground. The system, which rides along an overhead rail, provides both static and dynamic unloading, and has an active trolley that automatically follows the subject as they walk. Here, a small motor drives the system so that it stays directly above the subject as they walk over-ground. While the existing trolley tracking system works well for over-ground gait in individuals with slow walking speeds, it is limited in speed as well as the amount of force it can provide. Adding additional force to the trolley is important for controlling the forward momentum of the subject during falls and for stabilization when lifting the subject from their wheelchair or off the floor. In addition, our long-term goals are to add a sit-to-stand protocols as well as dynamic balance tasks, which will require additional force and better performance from the trolley. The goal of this Phase I SBIR is to retrofit the ZeroG trolley with a larger motor and to develop enhanced control algorithms that will improve subject tracking during over-ground gait and can be used for advanced training activities. The hardware and controllers developed in Phase I will then be utilized in the development of advanced postural and dynamic tasks in Phase II. Enhancing the capabilities of ZeroG throughout Phases I & II of this SBIR will allow individuals with lower limb impairments the ability to practice over-ground gait, as well as postural and dynamic balance tasks, making it one of the most versatile gait training systems in the world. As a result, we believe that individuals who train with ZeroG will experience enhanced gains in over-ground walking ability when compared to existing conventional rehabilitation strategies as ZeroG will allow therapists to train patients through a broad spectrum of activities early after neurological injuries in a safe, controlled manner. This system can be used in the functional rehabilitation of various disabling conditions, including stroke and spinal cord injury to amputations and with elderly individuals. In addition to clinical benefits, a body-weight support system of this nature can also be used to foster new research studies that focus on gait impairments. PUBLIC HEALTH RELEVANCE: Recent studies have reported that in the United States alone, more than 18% of the population (or equivalently 35.6 million individuals) suffer from some form of walking disorder that negatively impacts their ability to ambulate at a community level (DeJong et al., 2002). Walking disorders, defined as deficits in balance, stability and endurance while unsupported, are common to individuals following stroke, multiple sclerosis (MS), cerebral palsy (CP), spinal cord injury (SCI), amputation, and normal complications related to general aging. Unfortunately, the number of people who have trouble ambulating will continue to worsen in upcoming years due to our aging population. The US Census Bureau projects that the size of the elderly population (those 65 years or older) will rise from approximately 33+ million (12.7% of the US population in 1999) to 53 million in 2020 and 77 million by 2040 (U.S. Census Bureau, 2001). This trend raises significant concerns since over half of the elderly (36.3%) have some form of balance and gait impairment while approximately 17.9% have significant walking disorders (DeJong, 2002). Furthermore, the National Stroke Association has projected that in the next 20 years, the number of US citizens who suffer a stroke will surpass 1 million per year, where half of these stroke survivors will experience long-term disabilities including gait impairments (Stroke Association, 2008). Why is this an important health care issue? Deficits in balance control and walking disorders often result in individuals not feeling secure outside of their immediate environment, keeping them from truly re-integrating into society and from full social participation. Unfortunately treating these disorders has been severely hampered by economic pressures placed on rehabilitation centers by health-care providers. Today, rehabilitation centers have less time to treat their patients than ever before, where the median length of stay in inpatient rehabilitation therapy has decreased from 20 to 12 days between 1994 and 2001, while the proportional decreasing length of stay was greatest for orthopedic patients (Ottenbacheret al., 2004). This often results in rehabilitation centers being forced to discharge patients even though they are continuing to make significant gains in walking ability. The troubling paradox with this statistic is that extensive therapy after many neurological and musculoskeletal pathologies leads to significant returns in balance control and walking ability (Barbeauet al, 1998.). These improvements often allow these individuals to independently perform ADLs and in some cases, return to work. It is therefore imperative for therapists to have the appropriate tools to treat gait disorders in highly impaired subjects early after their injuries and with appropriate intensity. The system that will be further developed and tested in this SBIR will help address walking disorders across numerous subject populations, allowing therapists and clinicians to safely treat patients early in the stages of recovery, a factor known to be important to influencing gait outcomes (Horn et al., 2005).