Hybrid assistive limb (HAL) treatment for patients with severe thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL) in the postoperative acute/subacute phase: A clinical trial

Abstract

Context/Objective: The hybrid assistive limb (HAL) is a wearable exoskeleton robot that assists walking and lower limb movements via real-time actuator control. Our aim was to clarify the safety and feasibility of using the HAL robotic suit for rehabilitation in patients with severe thoracic myelopathy due to ossification of the posterior longitudinal ligament (T-OPLL). Design: Uncontrolled case series; pre-and post-intervention measurement. Setting: In-patient rehabilitation unit. Intervention: HAL training was provided in 60-minuts session, 2-3 sessions per week, for a total of 10 sessions. HAL training was initiated on average 27.5 days post-surgery. Patients: Eight patients (four males and four females; mean age, 60.9 ± 10.2 years) with severe myelopathy, who had undergone posterior decompression with instrumented fusion, were enrolled. Outcome Measures: Gait speed, step length and cadence were measured along a 10-m walkway every session. The American Spinal Injury Association (ASIA) motor score (lower extremities) and Walking Index for Spinal Cord Injury (WISCI) II were also evaluated at baseline and after 10 sessions. The Japanese Orthopaedic Association (JOA) score was calculated over time after surgery. Results: All participants completed the 10 training sessions, with no serious adverse effect noted. Gait speed, step length and cadence improved over time. Both the WISCI-II and ASIA motor (lower extremities) scores improved from baseline after 10 sessions. The JOA score improved over time post-surgery. Conclusion: HAL training can be feasibly initiated in the early postoperative period, without severe adverse events in patients, with T-OPLL-related severe gait disturbance.

Dropped Head Syndrome Attenuation by Hybrid Assistive Limb: A Preliminary Study of Three Cases on Cervical Alignment during Walking

“…Although there are multiple recent reports on functional gait recovery after using HAL in patients with mobility issues due to various neurological disorders [11][12][13][14][15][16][17][18], there are only very few studies focusing on using HAL for spinal deformity. Evaluating immediate and lasting effects of gait treatment using HAL for spinal deformity, this study investigated the cervical alignment during gait of three dropped head syndrome (DHS) patients who underwent a total of 10 HAL gait sessions at different frequencies.…”

“…It has electrically driven power units at the bilateral hip and knee joints, which are actuated, amplifying the neuro-muscular activation of the relevant lower-limb muscles. HAL is known to be effective for gait improvement after neurological motion impairments including stroke [11,12], myelopathy in acute and chronic phases after spine surgery [13], spinal cord injury [14][15][16][17], and cerebral palsy [18]. However, regardless of these recent reports, improvement of DHS using HAL is reported only for a case so far [10].…”

Rehabilitation Treatment of Motor Dysfunction Patients Based on Deep Learning Brain–Computer Interface Technology

“…In the 2012 Image Net competition, previous work won the competition by relying on the fivelayer convolution network model Alex Net constructed by the convolution neural network algorithm and achieved a good result of 1000 classification error rate of 100000 images with an error rate of 15.3% (Zhang et al, 2017). In recent years, through the continuous efforts of a large number of researchers and improving the 152-layer Res Net model designed by He K and others, the error rate has been reduced to 3.6% (Kubota et al, 2019), which makes the image recognition ability of machines surpass that of human beings. In Telles et al (2019), Deng et al used CNN to extract different kinds of features from EEG signals.…”

Muscular Activity Modulation During Post-operative Walking With Hybrid Assistive Limb (HAL) in a Patient With Thoracic Myelopathy Due to Ossification of Posterior Longitudinal Ligament: A Case Report

“…It actuates the electric motors embedded in the hips and knees of its exoskeleton in real time, amplifying bioelectric activation of the relevant muscles which are detected using surface electrodes attached on the hip and knee muscles. Previous studies using HAL for myelopathy (10)(11)(12), spinal cord injury (13)(14)(15)(16)(17), and post-surgery rehabilitation after total knee arthroplasty (18) reported improvement of walking ability after HAL training.…”

“…In previous studies on the application of HAL for postoperative gait rehabilitation of OPLL patients with thoracic myelopathy (10)(11)(12)(37)(38)(39), gait improvement is reported by comparing the state of the patient before starting and after finishing the entire robot-assisted intervention. However, this comparison hinders examination of the effect of the robot during the training per se, as well as how it differs from training without the robot.…”