A multidirectional gravity-assist algorithm that enhances locomotor control in patients with stroke or spinal cord injury

Abstract

Gait recovery after neurological disorders requires remastering the interplay between body mechanics and gravitational forces. Despite the importance of gravity-dependent gait interactions and active participation for promoting this learning, these essential components of gait rehabilitation have received comparatively little attention. To address these issues, we developed an adaptive algorithm that personalizes multidirectional forces applied to the trunk based on patient-specific motor deficits. Implementation of this algorithm in a robotic interface reestablished gait dynamics during highly participative locomotion within a large and safe environment. This multidirectional gravity-assist enabled natural walking in nonambulatory individuals with spinal cord injury or stroke and enhanced skilled locomotor control in the less-impaired subjects. A 1-hour training session with multidirectional gravity-assist improved locomotor performance tested without robotic assistance immediately after training, whereas walking the same distance on a treadmill did not ameliorate gait. These results highlight the importance of precise trunk support to deliver gait rehabilitation protocols and establish a practical framework to apply these concepts in clinical routine.

Emergence of Epidural Electrical Stimulation to Facilitate Sensorimotor Network Functionality After Spinal Cord Injury

“…In addition to technology developed to target stimulation of the spinal cord, robotic interfaces controlling physical rehabilitation delivered to the subject are being developed. For example, Courtine and colleagues have developed a robotic interface to evaluate stepping behavior following central nervous system injury in rats and a multidirectional gravity‐assist algorithm that enabled natural walking in non‐ambulatory humans . Continued development of these technologies may enhance functional outcomes beyond the results that have been demonstrated via EES in humans.…”

Review of clinical neurorestorative strategies for spinal cord injury: Exploring history and latest progresses

“…Collinger (2012) showed that a patient with tetraplegia is able to guide a robotic arm with thoughts through high-performance neuroprosthetic control [59]. Mignardot (2017) reported that the multidirectional gravity-assist enabled natural walking in non-ambulatory individuals with SCI and enhanced skilled locomotor control [60].…”

2017 Yearbook of Neurorestoratology

“…Nilakantan et al reported that hippocampal posteriormedial network using network-targeted noninvasive brain stimulation could improve memory through enhanced reactivation of detailed visuospatial information at retrieval [28]. Mignardot et al reported that training sessions with multidirectional gravity-assist improved locomotor performance tested without robotic assistance immediately after training, whereas walking the same distance on a treadmill did not ameliorate gait [29]. Some reports even showed that 5 days of repeated left prefrontal transcranial direct current stimulation [30] or repetitive transcranial magnetic stimulation [31] could improve recovery of consciousness in some chronic patients with disorders of consciousness such as minimally conscious state; however, the double-blind cross-over study showed that repeated transcranial direct current stimulation did not exert remarkable short-term clinical and EEG effects in patients with prolonged disorders of consciousness [32].…”