Robotic resistance treadmill training improves locomotor function in human spinal cord injury: a pilot study

Wu M, Landry JM, Schmit BD, Hornby TG, Yen S-C. Robotic resistance treadmill training improves locomotor function in human spinal cord injury: a pilot study.ObjectiveTo determine whether cable-driven robotic resistance treadmill training can improve locomotor function in humans with incomplete spinal cord injury (SCI).DesignRepeated assessment of the same patients with crossover design.SettingResearch units of rehabilitation hospitals in Chicago.ParticipantsPatients with chronic incomplete SCI (N=10) were recruited to participate in this study.InterventionsSubjects were randomly assigned to 1 of 2 groups. One group received 4 weeks of assistance training followed by 4 weeks of resistance training, while the other group received 4 weeks of resistance training followed by 4 weeks of assistance training. Locomotor training was provided by using a cable-driven robotic locomotor training system, which is highly backdrivable and compliant, allowing patients the freedom to voluntarily move their legs in a natural gait pattern during body weight supported treadmill training (BWSTT), while providing controlled assistance/resistance forces to the leg during the swing phase of gait.Main Outcome MeasuresPrimary outcome measures were evaluated for each participant before training and after 4 and 8 weeks of training. Primary measures were self-selected and fast overground walking velocity and 6-minute walking distance. Secondary measures included clinical assessments of balance, muscle tone, and strength.ResultsA significant improvement in walking speed and balance in humans with SCI was observed after robotic treadmill training using the cable-driven robotic locomotor trainer. There was no significant difference in walking functional gains after resistance versus assistance training, although resistance training was more effective for higher functioning patients.ConclusionsCable-driven robotic resistance training may be used as an adjunct to BWSTT for improving overground walking function in humans with incomplete SCI, particularly for those patients with relatively high function.     

机器人模式设计对脊髓损伤患者步态的影响

背景：治疗师帮助的减重运动平板训练方法是一种效果较好的步态训练方法,但因其对治疗师体力消耗较大,且人员需要较多,临床应用受到一定限制。机器人帮助的减重运动平板训练受到广泛关注。目的：总结机器人在脊髓损伤患者步态康复中的作用及其对下肢运动及肌肉活动模式的影响。方法：由第一作者检索PubMed数据库（http：//www.ncbi.nlm.nih.gov/PubMed）1995-01/2010-12涉及机器人、Lokomat、减重运动平板训练及脊髓损伤步态康复内容的文献,英文关键词为＂spinal cord injury, gait, walking, locomotor, locomotion,rehabilitation,robot,robotic,Lokomat＂,排除陈旧性、重复性文献,保留30篇文献归纳总结。结果与结论：虽然到时目前为止还没有证据证明机器人运动训练方法优越于其他方法,但其在脊髓损伤康复领域的应用也有明显的优势。机器人设备对下肢运动的被动引导及固定步行模式的重复训练不利于患者最大自主肌力的发挥及步行循环周期之间的变动,不能做到治疗师那样敏感地感受患者的运动表现。治疗师只有全面了解机器人设备并根据患者的运动能力不断调整训练参数,以致使患者在精确控制环境下最大限度地发挥自主运动能力,才能获得最佳的运动训练效果。     

Synchronous stimulation and monitoring of soleus H reflex during robotic body weight-supported ambulation in subjects with spinal cord injury

We evaluated the accuracy of a novel method for recording the soleus H reflex at specific points in the gait cycle during robotic locomotor training in subjects with spinal cord injury (SCI). Hip goniometric information from the Lokomat system defined midstance and midswing points within the gait cycle. Soleus H reflex stimulation was synchronized to these points during robotic-assisted ambulation at 1.8 and 2.5 km/h. Motor stimulus intensity was monitored and adjusted in real time. Analysis of 50 H reflex cycles during each speed and gait phase showed that stimulation accuracy was within 0.5 degrees of the defined hip joint position and that >85% of the H reflex cycles met the +/-10% M wave criterion that was established during quiet standing. This method allows increased consistency of afferent information into the segmental spinal and supraspinal circuitry and, thus, evaluation of H reflex characteristics during robotic ambulation in subjects with SCI.     

Locomotor training after human spinal cord injury: a series of case studies

Many individuals with spinal cord injury (SCI) do not regain their ability to walk, even though it is a primary goal of rehabilitation. Mammals with thoracic spinal cord transection can relearn to step with their hind limbs on a treadmill when trained with sensory input associated with stepping. If humans have similar neural mechanisms for locomotion, then providing comparable training may promote locomotor recovery after SCI. We used locomotor training designed to provide sensory information associated with locomotion to improve stepping and walking in adults after SCI. Four adults with SCIs, with a mean postinjury time of 6 months, received locomotor training. Based on the American Spinal Injury Association (ASIA) Impairment Scale and neurological classification standards, subject 1 had a T5 injury classified as ASIA A, subject 2 had a T5 injury classified as ASIA C, subject 3 had a C6 injury classified as ASIA D, and subject 4 had a T9 injury classified as ASIA D. All subjects improved their stepping on a treadmill. One subject achieved overground walking, and 2 subjects improved their overground walking. Locomotor training using the response of the human spinal cord to sensory information related to locomotion may improve the potential recovery of walking after SCI.     

Efficacy of rehabilitation robotics for walking training in neurological disorders: a review

Robotic technologies are becoming more prevalent for treating neurological conditions in clinical settings. We conducted a literature search of original articles to identify all studies that examined the use of robotic devices for restoring walking function in adults with neurological disorders. We evaluated and rated each study using either the Physiotherapy Evidence Database scale for randomized controlled trials (RCTs) or the Downs and Black scale for non-RCTs. We reviewed 30 articles (14 RCTs, 16 non-RCTs) that examined the effects of locomotor training with robotic assistance in patients following stroke, spinal cord injury (SCI), multiple sclerosis (MS), traumatic brain injury (TBI), and Parkinson disease (PD). This review supports that locomotor training with robotic assistance is beneficial for improving walking function in individuals following a stroke and SCI. Gait speed and endurance were not found to be significantly different among patients with motor incomplete SCI after a variety of locomotor training approaches. Limited evidence demonstrates that locomotor training with robotic assistance is beneficial in populations of patients with MS, TBI, or PD. We discuss clinical implications and decision making in the area of gait rehabilitation for neurological dysfunction.     

Robotic orthoses for body weight-supported treadmill training

BWSTT has become an accepted standard of care in gait rehabilitation methods. This type of locomotor training has many functional benefits, but the physical labor costs are considerable. To reduce therapist effort and improve the repeatability of locomotor training, three groups have developed commercially available robotic devices for assisted stepping. The purpose of these robotic devices is to augment locomotor rehabilitation by decreasing therapist manual assistance, increasing the amount of stepping practice, while decreasing therapist effort. Current clinical studies have yielded positive and promising results in locomotor rehabilitation inpatients with neurologic impairments of stroke or SCI. The potential benefits from robotic technology are significant for clinical use and research. As further research is conducted, rehabilitation therapists and patient outcomes will be able to contribute to the development of current and future technologies.     

机器人模式设计对脊髓损伤患者步态的影响

背景:治疗师帮助的减重运动平板训练方法是一种效果较好的步态训练方法,但因其对治疗师体力消耗较大,且人员需要较多,临床应用受到一定限制.机器人帮助的减重运动平板训练受到广泛关注.目的:总结机器人在脊髓损伤患者步态康复中的作用及其对下肢运动及肌肉活动模式的影响.方法:由第一作者检索PubMed数据库(http://www.ncbi.nlm.nih.gov/PubMed)1995-01/2010-12涉及机器人、Lokomat、减重运动平板训练及脊髓损伤步态康复内容的文献,英文关键词为“spinal cord injury,gait,walking,locomotor,locomotion,rehabilitation,robot,robotic,Lokomat ",排除陈旧性、重复性文献,保留30篇文献归纳总结.结果与结论:虽然到时目前为止还没有证据证明机器人运动训练方法优越于其他方法,但其在脊髓损伤康复领域的应用也有明显的优势.机器人设备对下肢运动的被动引导及固定步行模式的重复训练不利于患者最大自主肌力的发挥及步行循环周期之间的变动,不能做到治疗师那样敏感地感受患者的运动表现.治疗师只有全面了解机器人设备并根据患者的运动能力不断调整训练参数,以致使患者在精确控制环境下最大限度地发挥自主运动能力,才能获得最佳的运动训练效果.     

多位姿下肢康复机器人床身高度自动调整算法

目的 设计多位姿下肢康复机器人床身高度自动调整算法,以适应患者腿长和训练模式的差异,避免康复机器人与地面碰撞。方法 根据多位姿下肢康复机器人的6种训练模式和人体关节约束条件,建立不同模式下机器人床身高度与患者腿长和床身翻转角度的数学模型,分析机械间隙和挠变以及运动过程中腿部支架的抖动误差可能造成的影响;开发相关软件实现床身自动调整。招募志愿者10例进行实测。结果 床身高度实验测试数据与理论计算数据一致,间隙及挠变不影响床身高度理论计算。训练过程中,机器人下肢末端始终与地面保持在设定的安全距离以上。结论 建立的算法能根据患者腿长、训练模式、床身翻转角度实现床身自动调整,保证设备运行在安全范围。     

Unexpected recovery after robotic locomotor training at physiologic stepping speed: a single-case design

Spiess MR, Jaramillo JP, Behrman AL, Teraoka JK, Patten C. Unexpected recovery after robotic locomotor training at physiologic stepping speed: a single-case design.ObjectivesTo investigate the effect of walking speed on the emergence of locomotor electromyogram (EMG) patterns in an individual with chronic incomplete spinal cord injury (SCI), and to determine whether central pattern generator activity during robotic locomotor training (RLT) transfers to volitional EMG activity during overground walking.DesignSingle-case (B-A-B; experimental treatment–withdrawal–experimental treatment) design.SettingFreestanding rehabilitation research center.ParticipantA 50-year-old man who was nonambulatory for 16 months after incomplete SCI (sub-T11).InterventionsThe participant completed two 6-week blocks of RLT, training 4 times per week for 30 minutes per session at walking speeds up to 5km/h (1.4m/s) over continuous bouts lasting up to 17 minutes.Main Outcome MeasuresSurface EMG was recorded weekly during RLT and overground walking. The Walking Index for Spinal Cord Injury (WISCI-II) was assessed daily during training blocks.ResultsDuring week 4, reciprocal, patterned EMG emerged during RLT. EMG amplitude modulation revealed a curvilinear relationship over the range of walking speeds from 1.5 to 5km/h (1.4m/s). Functionally, the participant improved from being nonambulatory (WISCI-II 1/20), to walking overground with reciprocal stepping using knee-ankle-foot orthoses and a walker (WISCI-II 9/20). EMG was also observed during overground walking. These functional gains were maintained greater than 4 years after locomotor training (LT).ConclusionsHere we report an unexpected course of locomotor recovery in an individual with chronic incomplete SCI. Through RLT at physiologic walking speeds, it was possible to activate the central pattern generator even 16 months postinjury. Further, to a certain degree, improvements from RLT transferred to overground walking. Our results suggest that LT-induced changes affect the central pattern generator and allow supraspinal inputs to engage residual spinal pathways.     

Basic concepts of activity-based interventions for improved recovery of motor function after spinal cord injury

Roy RR, Harkema SJ, Edgerton VR. Basic concepts of activity-based interventions for improved recovery of motor function after spinal cord injury. Spinal cord injury (SCI) is a devastating condition that affects a large number of individuals. Historically, the recovery process after an SCI has been slow and with limited success. Recently, a number of advances have been made in the strategies used for rehabilitation, resulting in marked improved recovery, even after a complete SCI. Several rehabilitative interventions, that is, assisted motor training, spinal cord epidural stimulation, and/or administration of pharmacologic agents, alone or in combination, have produced remarkable recovery in motor function in both humans and animals. The success with each of these interventions appears to be related to the fact that the spinal cord is smart, in that it can use ensembles of sensory information to generate appropriate motor responses without input from supraspinal centers, a property commonly referred to as central pattern generation. This ability of the spinal cord reflects a level of automaticity, that is, the ability of the neural circuitry of the spinal cord to interpret complex sensory information and to make appropriate decisions to generate successful postural and locomotor tasks. Herein, we provide a brief review of some of the neurophysiologic rationale for the success of these interventions.     

Predicting Duration of Outpatient Physical Therapy Episodes for Individuals with Spinal Cord Injury Based on Locomotor Training Strategy

ObjectiveTo characterize individuals with spinal cord injuries (SCI) who use outpatient physical therapy or community wellness services for locomotor training and predict the duration of services, controlling for demographic, injury, quality of life, and service and financial characteristics. We explore how the duration of services is related to locomotor strategy.DesignObservational study of participants at 4 SCI Model Systems centers with survival. Weibull regression model to predict the duration of services.SettingRehabilitation and community wellness facilities at 4 SCI Model Systems centers.ParticipantsEligibility criteria were SCI or dysfunction resulting in motor impairment and the use of physical therapy or community wellness programs for locomotor/gait training. We excluded those who did not complete training or who experienced a disruption in training greater than 45 days. Our sample included 62 participants in conventional therapy and 37 participants in robotic exoskeleton training.InterventionsOutpatient physical therapy or community wellness services for locomotor/gait training.Main Outcome MeasuresSCI characteristics (level and completeness of injury) and the duration of services from medical records. Self-reported perceptions of SCI consequences using the SCI-Functional Index for basic mobility and SCI-Quality of Life measurement system for bowel difficulties, bladder difficulties, and pain interference.ResultsAfter controlling for predictors, the duration of services for the conventional therapy group was an average of 63% longer than for the robotic exoskeleton group, however each visit was 50% shorter in total time. Men had an 11% longer duration of services than women had. Participants with complete injuries had a duration of services that was approximately 1.72 times longer than participants with incomplete injuries. Perceived improvement was larger in the conventional group.ConclusionsLocomotor/gait training strategies are distinctive for individuals with SCI using a robotic exoskeleton in a community wellness facility as episodes are shorter but individual sessions are longer. Participants’ preferences and the ability to pay for ongoing services may be critical factors associated with the duration of outpatient services.     

Neuroanatomical substrates of functional recovery after experimental spinal cord injury: implications of basic science research for human spinal cord injury

Human spinal cord injury (SCI) is a devastating condition that results in persistent motor deficits. Considerable basic and clinical research is directed at attenuating these deficits. Many basic scientists use animal models of SCI to (1) characterize lesion development, (2) determine the role of spared axons in recovery, and (3) develop therapeutic interventions based on these findings. In this article, current research is reviewed that indicates: (1) most individuals with SCI will have some sparing of white matter at the lesion epicenter even when the lesion appears clinically complete, (2) even minimal tissue sparing has a profound impact on segmental systems and recovery of function, and (3) facilitatory intervention such as weight bearing and locomotor training after SCI may be more effective than compensatory strategies at inducing neuroplasticity and motor recovery. Body weight supported treadmill step training is discussed as an example of new facilitatory interventions based on basic science research using animal models.     

Locomotor training within an inpatient rehabilitation program after pediatric incomplete spinal cord injury

BACKGROUND AND PURPOSE: The outcomes of intense locomotor training after incomplete spinal cord injury (SCI) have been described in adults with acute and chronic injuries and with various levels of ambulatory function. This case report describes a comprehensive inpatient rehabilitation program with a locomotor training component in a child with a severe incomplete SCI. CASE DESCRIPTION: A 5-year-old girl injured at C4 participated in locomotor training for 5 months during inpatient rehabilitation. OUTCOMES: The patient's Functional Independence Measure for Children II (WeeFIM II) mobility score increased from 5/35 to 21/35. Her Walking Index for Spinal Cord Injury II (WISCI II) score improved from 0 to 12. The patient returned to walking in the community with assistive devices. DISCUSSION: It is feasible to include an intense locomotor training program in the clinical rehabilitation setting for a child with a severe SCI, and the outcomes were consistent with results in adults. Further investigation with experimental designs and more participants will determine the extent to which this intervention benefits the pediatric population with SCI.     

Relationship Between ASIA Examination and Functional Outcomes in the NeuroRecovery Network Locomotor Training Program

Buehner JJ, Forrest GF, Schmidt-Read M, White S, Tansey K, Basso DM. Relationship between ASIA examination and functional outcomes in the NeuroRecovery Network Locomotor Training Program.ObjectiveTo determine the effects of locomotor training on: (1) the International Standards for Neurological Classification of Spinal Cord Injury examination; (2) locomotion (gait speed, distance); (3) balance; and (4) functional gait speed stratifications after chronic incomplete spinal cord injury (SCI).DesignProspective observational cohort.SettingOutpatient rehabilitation centers in the NeuroRecovery Network (NRN).ParticipantsIndividuals (n=225) with American Spinal Injury Association Impairment Scale (AIS) grade C or D chronic motor incomplete SCI having completed locomotor training in the NRN.InterventionThe NRN Locomotor Training Program consists of manual-facilitated body weight–supported standing and stepping on a treadmill and overground.Main Outcome MeasuresAIS classification, lower extremity pin prick, light touch and motor scores, ten-meter walk and six-minute walk tests, and the Berg Balance Scale.ResultsSignificant gains occurred in lower extremity motor scores but not in sensory scores, and these were only weakly related to gait speed and distance. Final Berg Balance Scale scores and initial lower extremity motor scores were positively related. Although 70% of subjects showed significantly improved gait speed after locomotor training, only 8% showed AIS category conversion.ConclusionsLocomotor training improves gait speed to levels sufficient for independent in-home or community ambulation after chronic motor incomplete SCI. Changes in lower extremity motor and sensory scores do not capture the full extent of functional recovery, nor predict responsiveness to locomotor training. Functional classification based on gait speed may provide an effective measure of treatment efficacy or functional improvement after incomplete SCI.     

Recovery of Sensory and Supraspinal Control of Leg Movement in People With Chronic Paraplegia: A Case Series

Objective

To report on unexpected findings in 4 patients with chronic paraplegia who underwent the laparoscopic implantation of neuroprosthesis procedure in the pelvic lumbosacral nerves.

Design

Observational case series.

Setting

Tertiary referral unit specialized in advanced gynecological surgery and neuropelveology.

Participants

Three patients with incomplete American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade B (n=2) and AIS grade C (n=1) spinal cord injury (SCI) and 1 patient with flaccid complete chronic SCI (AIS grade A) (n=1).

Intervention

Functional electrical stimulation (FES)-assisted locomotor training and continuous low-frequency pelvic-lumbosacral neuromodulation.

Main Outcome Measures

Change in ASIA Lower Extremity Motor Scores, ASIA sensory scores for light touch and pinprick sensation, and Walking Index for Spinal Cord Injury scores.

Results

All 4 patients developed progressive recovery of some sensory and voluntary motor functions below the lesions. Three are currently capable of voluntary weight-bearing standing and walking a few meters with a walker without FES. The first patient with the longest follow-up is even capable of electrically assisted standing/walking with 2 crutches without braces or assistance for a distance of about 900 meters, and of weight-bearing standing and walking for 30 meters with a walker without stimulation.

Conclusions

We report unexpected sensory and locomotor recovery in 4 people with paraplegia with SCI. Our findings suggest that FES-assisted locomotor training with continuous low-frequency pelvic nerve stimulation in patients with SCI may induce changes that affect the central pattern generator and allow supra- and infraspinal inputs to engage residual spinal pathways.     

Exoskeletons for Personal Use After Spinal Cord Injury

Before the development of robotic exoskeletons, mobility options beyond a wheelchair were very limited for most people lacking leg movement due to spinal cord injury (SCI). Over the years, robotic exoskeletons have become more widely available and now have the potential to be successfully used for personal use at home and in the community. However, it is important that users set realistic expectations. The features and capabilities of each robotic exoskeleton differ, and how exoskeletons are used may vary greatly between individuals. Robotic exoskeletons can allow individuals with SCI with varying levels of injury to safely and functionally walk for personal mobility or exercise. The following special communication will discuss important considerations surrounding exoskeleton use including feasibility, safety, cost, speed, and potential health benefits of using an exoskeleton for everyday life for people with SCI.     

Retraining of interjoint arm coordination after stroke using robot-assisted time-independent functional training

We have developed a haptic-based approach for retraining of interjoint coordination following stroke called time-independent functional training (TIFT) and implemented this mode in the ARMin III robotic exoskeleton. The ARMin III robot was developed by Drs. Robert Riener and Tobias Nef at the Swiss Federal Institute of Technology Zurich (Eidgenossische Technische Hochschule Zurich, or ETH Zurich), in Zurich, Switzerland. In the TIFT mode, the robot maintains arm movements within the proper kinematic trajectory via haptic walls at each joint. These arm movements focus training of interjoint coordination with highly intuitive real-time feedback of performance; arm movements advance within the trajectory only if their movement coordination is correct. In initial testing, 37 nondisabled subjects received a single session of learning of a complex pattern. Subjects were randomized to TIFT or visual demonstration or moved along with the robot as it moved though the pattern (time-dependent [TD] training). We examined visual demonstration to separate the effects of action observation on motor learning from the effects of the two haptic guidance methods. During these training trials, TIFT subjects reduced error and interaction forces between the robot and arm, while TD subject performance did not change. All groups showed significant learning of the trajectory during unassisted recall trials, but we observed no difference in learning between groups, possibly because this learning task is dominated by vision. Further testing in stroke populations is warranted.     

脊髓步行中枢模式发生器

一般认为，哺乳动物（包括人在内）都是通过脊髓步行中枢模式发生器（CPG）控制步行运动，而CPG网络的边界是灵活的，脊髓损伤后脊髓步行CPG可实现网络重组。研究显示，减重步行平板训练（BWSTT）可使脊髓横断猫完全恢复后肢步行能力；临床也发现，脊髓损伤患者可通过BWSTT提高步行能力，表明脊髓可能具有运动学习的能力。因此，如何利用脊髓步行CPG的神经可塑性，为脊髓损伤患者制定最佳的步行训练方案，是令人关注的问题。     

Asymmetric lower-limb bone loss after spinal cord injury: case report

Osteoporosis is a significant secondary condition that occurs acutely after spinal cord injury (SCI). This article reports on a patient with motor incomplete SCI and asymmetric lower-limb bone loss as it correlates with lower-limb motor function and gait characteristics. A 32-year-old Caucasian male completed a comprehensive inpatient rehabilitation program, including 3 months of robotic body-weight-supported treadmill training three times a week. Bone mineral density (BMD) was monitored up to 1.5 years post-SCI by dual-energy X-ray absorptiometry. Ground reaction forces were measured through an instrumented treadmill for bilateral weight-bearing comparison. At 1.5 years postinjury, neurological examination revealed thoracic 4 American Spinal Injury Association Impairment Scale D SCI with less strength, reduced weight bearing, and lower BMD in the more neurologically impaired leg. These results suggest that osteoporosis may vary according to severity of impairment within individuals and that monitoring lower-limb BMD is especially important for patients who ambulate.     

Musculoskeletal responses of spinal cord injured individuals to functional neuromuscular stimulation-induced knee extension exercise training

This study was conducted to evaluate a newly designed functional neuromuscular stimulation (FNS)-induced knee extension (KE) exercise system that incorporates the most desired features of previously described systems by determining the musculoskeletal responses of spinal cord injured (SCI) individuals to training. A specially designed chair and electrical stimulator were fabricated for FNS-induced KE resistance exercise. Surface electrodes were placed over motor points of the quadriceps muscles, and KE was alternated between legs at an average rate of 6 KE/min/leg. KE testing protocols were developed for pre- and post-training evaluations of performance, and 12 SCI subjects exercise-trained up to three times per week for 36 sessions using a progressive resistance load at ankle level. Pre- and post-training evaluation data were statistically compared using a 0.05 level for significance. Quadriceps muscle performance (strength x repetitions) improved for both legs in all subjects as indicated by significant increases in load resistance and repetitions over the 36-session training period (right leg mean = 1156.0 versus 1624.8 kg.reps, left leg mean = 1127.3 versus 1721.1 kg.reps). In addition, knee range of motion significantly increased (right leg mean = 134 versus 146 degrees, left leg mean = 133 versus 144 degrees). Thigh skinfold, thigh girth, body weight and bone density were not significantly changed. The lack of decrease in bone density in some subjects suggests that the training may retard the rate of bone loss which typically occurs with SCI. No injuries or problems were encountered during testing and training.(ABSTRACT TRUNCATED AT 250 WORDS)