Robotic Assistance That Encourages the Generation of Stepping Rather than Fully 2 Assisting Movements Is Best for Learning to Step in Spinally Contused Rats 3 4
نویسندگان
چکیده
24 25 Resubmitted to Journal Neurophysiology 26 1 27 ABSTRACT 28 Robotic devices have been developed to assist body weight supported 29 treadmill training in individuals with spinal cord injuries and stroke. Recent 30 findings have raised questions about the effectiveness of robotic training that fully 31 assisted stepping movements. The purpose of this study was to examine 32 whether assist-as-needed robotic training was better than fully assisting 33 movements in rats with incomplete spinal cord injury. Electromyography 34 electrodes were implanted in the tibialis anterior and medial gastrocnemius 35 hindlimb muscles of fourteen adult rats. Afterwards, the rats received a severe 36 mid-thoracic spinal cord contusion and began daily weight supported treadmill 37 training 1 week later using a rodent robotic system. During training, assistive 38 forces were applied to the ankle when it strayed from a desired stepping 39 trajectory. The amount of force was proportional to the magnitude of the 40 movement error and this was multiplied by either a high or low scale factor to 41 implement the full assistance (n=7) or assist-as-needed algorithms (n=7), 42 respectively. Thus, full assistance training drove the ankle along the desired 43 trajectory whereas greater variety in ankle movements occurred during assist-as-44 needed training. After four weeks of training, locomotor recovery was greater in 45 the assist-as-needed group, as demonstrated by the ability to generate steps 46 without assistance, more normal-like kinematic characteristics and greater EMG 47 2 activity. The findings suggested that flexible robotic assistance facilitated learning 48 to step after a spinal cord injury. These findings support the rationale for the use 49 of assist-as-needed robotic training algorithms in human robotic-assisted 50 BWSTT. 51 52 KEYWORDS 53 Electromyography, treadmill, spinal cord injury 54 55 3 Introduction 56 Body weight supported treadmill training (BWSTT) is a form of gait training 57 in which trainers assist leg, hip and trunk movements during treadmill locomotion. 58 Clinical studies have shown that BWSTT improved locomotor function in humans 59 following spinal cord injury (SCI; (Wernig et al., 1995) and stroke (Sullivan et al., 60 2007). Implementing BWSTT can be difficult for trainers because often times a 61 great deal of effort is required to assist movements. To facilitate BWSTT, robotic 62 devices have been developed that fully assist stepping by imposing forces that 63 continually move the limbs through the step cycle (Colombo et al., 2000; Hesse 64 et al., 2000). Recently, …
منابع مشابه
Robotic assistance that encourages the generation of stepping rather than fully assisting movements is best for learning to step in spinally contused rats.
Robotic devices have been developed to assist body weight-supported treadmill training (BWSTT) in individuals with spinal cord injuries (SCIs) and stroke. Recent findings have raised questions about the effectiveness of robotic training that fully assisted (FA) stepping movements. The purpose of this study was to examine whether assist-as-needed robotic (AAN) training was better than FA movemen...
متن کاملRobotic loading during treadmill training enhances locomotor recovery in rats spinally transected as neonates.
Loading on the limbs has a powerful influence on locomotion. In the present study, we examined whether robotic-enhanced loading during treadmill training improved locomotor recovery in rats that were spinally transected as neonates. A robotic device applied a force on the ankle of the hindlimb while the rats performed bipedal stepping on a treadmill. The robotic force enhanced loading during th...
متن کاملA New Nonlinear Autoregressive Exogenous (NARX)-Based Intra-Spinal Stimulation Approach to Decode Brain Electrical Activity for Restoration of Leg Movement in Spinally-Injured Rabbits
This study aims at investigation of stimulation by using intra-spinal signals decoded from electrocorticography (ECoG) assessments to restore the movements of the leg in an animal model of spinal cord injury (SCI). The present work comprised of three steps. First, ECoG signals and the associated leg joint changes (hip, knee, and ankle) in sedated healthy rabbits were recorded in different trial...
متن کاملAdaptations in glutamate and glycine content within the lumbar spinal cord are associated with the generation of novel gait patterns in rats following neonatal spinal cord transection.
After spinal cord transection, the generation of stepping depends on neurotransmitter systems entirely contained within the local lumbar spinal cord. Glutamate and glycine likely play important roles, but surprisingly little is known about how the content of these two key neurotransmitters changes to achieve weight-bearing stepping after spinal cord injury. We studied the levels of glutamate an...
متن کاملEffective robotic assistive pattern of treadmill training for spinal cord injury in a rat model
The purpose of the present study was to establish an effective robotic assistive stepping pattern of body-weight-supported treadmill training based on a rat spinal cord injury (SCI) model and assess the effect by comparing this with another frequently used assistive stepping pattern. The recorded stepping patterns of both hind limbs of trained intact rats were edited to establish a 30-sec playb...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2011