Hybrid Assistive Limb Training Research Articles

Muscle Strength and Efficiency of Muscle Activities Recovery Using Single-Joint Type Hybrid Assistive Limb in Knee Rehabilitation after Anterior Cruciate Ligament Reconstruction.

Decreased muscle strength often occurs after anterior cruciate ligament (ACL) reconstruction; this can include muscle atrophy, neuromuscular dysfunction, and reduced force generation efficiency. Hybrid assistive limb (HAL) technology, which integrates an interactive biofeedback system connecting the musculoskeletal system to the brain and spinal motor nerves, offers a potential intervention. Our study, conducted from March 2018 to August 2023 using knee HAL single-joint technology, was a prospective non-randomized controlled trial involving 27 patients who had undergone arthroscopic ACL reconstruction. They were split into two groups: HAL (18 patients) and control (nine patients). Beginning 18 weeks after their surgery, the HAL group participated in three weekly sessions of knee HAL-assisted exercises. Both the HAL and control groups underwent isokinetic muscle strength tests at postoperative weeks 17 and 21. Testing utilized an isokinetic dynamometer at 60°/s, 180°/s, and 300°/s. The Limb Symmetry Index (LSI) was employed to measure side-to-side differences. The HAL group showed significant LSI improvements in peak extension torque across all testing velocities and for peak flexion torque at 60°/s and 300°/s. The rate of change in LSI for peak flexion torque at 300°/s was significantly higher post-measurements (p = 0.036; effect size = 1.089). The change rate for LSI in peak extension torque at 300°/s and all peak flexion torques showed medium to large effect sizes in Cohen's d. In conclusion, knee HAL single-joint training positively influenced muscle strength recovery and efficiency. The HAL training group exhibited superior muscle strength at various isokinetic testing velocities compared to the control group.

Feasibility and Efficacy of the Newly Developed Robotic Hybrid Assistive Limb Shoulder Exercises in Patients with C5 Palsy during the Acute Postoperative Phase.

Background and Objectives: Although postoperative C5 palsy is a frequent complication of cervical spine surgery, no effective therapeutic rehabilitation approach has been established for postoperative C5 palsy. The purpose of this study was to find evidence confirming the effectiveness and feasibility of robotic Hybrid Assistive Limb (HAL) shoulder exercises for C5 palsy. Materials and Methods: In this before-after, uncontrolled case series clinical study, we performed a mean of 11.7 shoulder training sessions using a shoulder HAL immediately after the onset of C5 palsy in seven shoulders of six patients who developed postoperative C5 palsy and had difficulty raising their shoulder during the acute postoperative phase of cervical spine surgery. Shoulder HAL training was introduced as early as possible after evaluating the general condition of all inpatients who developed C5 palsy. Patients underwent shoulder abduction training using shoulder HAL on an inpatient and outpatient basis at 2-week or 1-month intervals. Adverse events associated with shoulder HAL training were investigated. The shoulder abduction angle and power without the shoulder HAL were evaluated before shoulder HAL usage, at every subsequent session, and upon completion of all sessions. Results: Severe adverse events due to shoulder HAL training were not reported. After completion of all shoulder HAL sessions, all patients showed improved shoulder elevation, while shoulder abduction angle and power improved over time. Conclusions: Shoulder elevation training with HAL in patients in the acute stage of postoperative C5 palsy has the potential to demonstrate improvement in shoulder joint function with a low risk of developing severe adverse events.

New Neuromuscular Training for Peripheral Nerve Disorders Using an Ankle Joint Hybrid Assistive Limb: A Case Series.

Peripheral nerve disorder of the lower extremities causes drop foot and disturbs the daily living activities of patients. The ankle joint hybrid assistive limb (HAL) provides voluntary ankle joint training using surface bioelectrical signals from the muscles of the lower extremities. We investigated the neurological effects of ankle joint HAL training in three patients. Sensory nerve action potentials (SNAPs) and compound muscle action potentials (CMAPs) were analyzed for the peroneal and tibial nerves prior to the first ankle joint HAL training session. Integrated surface electromyography EMG signals were recorded before and after the HAL training sessions to evaluate the effects of training for neuromuscular disorders. The patients were hospitalized to receive rehabilitation with HAL training for 2 weeks. The HAL training was performed daily with two 60 min sessions. All cases demonstrated severe neuromuscular impairment according to the result of the CMAP. All integrated EMG measurements of antagonistic muscle activities decreased after the ankle joint HAL training. The manual muscle testing (MMT) scores of each muscle were slightly increased after the HAL intervention for Case 2(tibialis anterior, from 2 to 2+; gastrocnemius muscles, from 2- to 2; extensor digitorum longus, and extensor hallucis longus, from 1 to 3). The MMT scores were also slightly increased except for gastrocnemius muscle for Case 3 (tibialis anterior, extensor digitorum longus, and extensor hallucis longus, from 2- to 2). These two patients demonstrated voluntary muscle contractions and nerve signals in the CMAP before the HAL training. Even though the amplitude of CMAPs was low, the HAL training may provide voluntary ankle joint movements by reducing the antagonistic muscle contraction via computer processing. The HAL training may enhance muscle movement and coordination through motor learning feedback.

Safety and Feasibility of Robot-assisted Gait Training in Adults with Cerebral Palsy in an Inpatient Setting – an Observational Study

Background: To investigate the safety and feasibility of six sessions of Hybrid Assistive Limb (HAL) robot-assisted gait training (RAGT) integrated into an inpatient therapy concept and their influence on walking speed and gait parameters in adult CP patients. Methods: Eleven subjects (male = 8, female = 3, mean age: 23 years and 2 months, ± 4.5 years) with spastic CP underwent six 20-minute RAGT sessions with the HAL during an 11-day hospital stay. Additionally, physiotherapy, physician-performed manual medicine, massage and exercise therapy were provided. Pre- (T1) and post- (T2) intervention assessments were: 10-metre walking test (10MWT), 6-minute walking test (6MWT), Gross Motor Function Measure (GMFM-88) and lower extremities passive range of motion (pROM). Results: All subjects completed the study. No adverse events were noted. Walking speed in the 10MWT test increased from 32.5 s (± 24.5 s) at T1 to 27.5 s (± 21.4 s) at T2, without significance. Slight, but non-significant improvements were detected in the 6MWT, GMFM and pROM. Confounding factors did not significantly affect the results. Conclusion: Intensive therapy including HAL training leads to non-significant improvements. Further studies with more patients and longer intervention time could provide further insights into the RAGT therapy of adult patients with CP. Registration DRKS-ID: DRKS00020275.

Robot-assisted rehabilitation for total knee or hip replacement surgery patients: A systematic review and meta-analysis.

Background:This study was performed to update the current evidence and evaluate the effects of robot-assisted rehabilitation (RAR) in comparison with conventional rehabilitation (CR) in patients following total knee (TKR) or hip replacements (THR).Methods:PubMed Central, OVID Medline, Cochrane Collaboration Library, and EMBASE for a comprehensive search for all relevant studies, from database inception to July 2022. The following inclusion criteria were used to determine eligibility for studies: randomized and matched controlled trials recruiting men and women who underwent TKR and THR; and studies examining the effect of RAR on outcome measures of physical function and pain.Results:A total of 9 studies (230 patients) were included in this review and 4 were included in the meta-analysis. The meta-analysis of 2 studies showed that Hybrid Assistive Limb (HAL) training for 5 days, significantly improved pain measured on a visual analogue scale, compared to CR in patients following TKR (SMD = 1.05, 95% confidence interval [Cl] 0.39–1.71). Heterogeneity for I2 value was lower than moderate (tau^2 = 0.0121; I2 = 5%; P = .30). There were 2 studies that assessed self-selected walking speed. The meta-analysis of these studies showed that HAL training was significantly superior to CR in patients following TKR (SMD = 48.70, 95% Cl -50.53 to 147.94) at 2 months. A high heterogeneity was detected (P < .01; I2 = 97%).Conclusion:The result of this systematic review and meta-analysis suggest that RAR may be an effective treatment in TKR and THR patients. However, high-quality studies are needed to verify the long-term effect on their recovery.

Functional magnetic resonance imaging of brain activity during hybrid assistive limb intervention in a chronic spinal cord injury patient with C4 quadriplegia

Hybrid assistive limb (HAL) is a wearable robot, which has recently been used for the treatment of patients with movement disorders including spinal cord injury (SCI). Although several studies have indicated the effectiveness of HAL for SCI patients, changes in brain activity during the HAL intervention have not yet been fully characterized. A 19-year-old man with a chronic SCI resulting in complete C4 quadriplegia underwent five weeks of HAL training for a total of ten sessions. We evaluated his brain activity using task-induced functional MRI (fMRI) after the fourth, sixth and tenth HAL sessions. We also assessed the spasticity of this patient using the modified Ashworth scale (mAs). As controls for the task-induced fMRI, we examined the brain activity in two healthy subjects. The fMRI findings indicated an increased response to a motor imagery task in the patient's cerebral cortex compared to controls. In addition, the activation pattern in his cortex changed during the five weeks of HAL intervention. We observed increased cerebral lateralization in his primary motor cortex. We also found that the laterality index calculated for the precentral gyrus had a significant negative correlation with the total mAs score over the course of the HAL treatment. Our results indicate that the cerebral cortex of the present SCI patient was hyperactive during the imagery task, and the cortical activation was reduced with progression of the HAL treatment.

Virtual Rehabilitation of Elbow Flexion Following Nerve Transfer Reconstruction for Brachial Plexus Injuries Using the Single-Joint Hybrid Assisted Limb

PurposeThe upper limb single-joint hybrid assistive limb (HAL), a wearable robot that can support elbow flexion and extension motions, was originally used to rehabilitate patients with stroke. We report the preliminary outcomes of serial HAL use for rehabilitation following nerve transfer (NT) for elbow flexion reconstruction in brachial plexus injuries.MethodsHybrid assistive limb training consisted of virtual and power training courses. Virtual training was started before HAL picked up motor unit potentials (MUPs) from the target muscle through electrodes attached to the skin overlying the original donor muscles. Power training was started after the maturation of MUPs, the stage where the MUPs were strong to be recognized to arise from the target muscles. Hybrid assistive limb assist at this stage was carried out by decreasing the settings in an inversely proportionate manner to the increase in target muscle strength. Fourteen patients underwent HAL training following NT. Eight patients had the intercostal nerve to musculocutaneous nerve (ICN-MCN) transfer, and their postoperative functional outcomes and rehabilitation performance were compared to 50 patients with ICN-MCN transfer who underwent conventional postoperative rehabilitation with electromyographic biofeedback (EMG-BF) techniques.ResultsComparison of the long-term results following ICN-MCN transfer between EMG-BF and HAL groups showed similar follow-up times, elbow flexion range of motion, or power of elbow flexion assessed using the British Medical Council grade, and quantitative measurement using Kin-Com dynamometer. However, the number of rehabilitation sessions was significantly fewer in the HAL than EMG-BF group.ConclusionHAL training accelerated patients’ learning to convert the original muscle function into elbow flexion following NT by replicating elbow flexion during the pre-MUP detection stage and shortening the rehabilitation time.Type of study/level of evidenceTherapeutic IV.

Effect of gait training using Hybrid Assistive Limb on gait ability and the risk for overwork weakness in the lower limb muscles in patients with neuromuscular disease: a proof-of-concept study.

Few previous studies have reported the efficacy of robot rehabilitation for improving gait ability or its adverse events in patients with neuromuscular diseases. The aim of the present study was to elucidate the effects of gait training with a hybrid assistive limb (HAL) on gait ability and to investigate serum enzyme levels associated with skeletal muscle damage. Proof-of-concept study. Department of rehabilitation medicine in university hospital. Twenty-one patients with neuromuscular disease (NMD, 13 males and 8 females, mean age of 60.6 years). All patients underwent 1 to 5 series of gait rehabilitation which consisted of 9 sessions of HAL training. Gait ability was assessed with the 10-meter walk test and the 2-min walk test before and after HAL training, while serum creatine phosphokinase, aspartate aminotransferase, and lactic acid dehydrogenase values were measured before, midway through, and after HAL training. Gait velocity and step length for 10-meter walk test, and 2-min walk distance were significantly improved after HAL gait training. There was no significant change in serum level of all 3 measured enzymes between the three time points. HAL gait training with the practical setting as this study improved gait ability in patients with progressive NMD and did not damage skeletal muscle, as indicated by no significant change in serum level of muscle enzymes. Robot assisted gait training could be safely applied to the patients with NMD, as one of the effective rehabilitation programs to improve gait ability.

Efficacy and Safety Study of Wearable Cyborg HAL (Hybrid Assistive Limb) in Hemiplegic Patients With Acute Stroke (EARLY GAIT Study): Protocols for a Randomized Controlled Trial.

We hypothesized that gait treatment with a wearable cyborg Hybrid Assistive Limb (HAL) would improve the walking ability of patients with hemiparesis after stroke. This study aims to evaluate the efficacy and safety of gait treatment using HAL versus conventional gait training (CGT) in hemiplegic patients with acute stroke and establish a protocol for doctor-initiated clinical trials for acute stroke. We will enroll patients with acute stroke at the University of Tsukuba Hospital. This study is a single-center, randomized, parallel-group, controlled trial (HAL group, n = 20; control group, n = 20) that will include three phases: (1) pre-observation phase (patient enrollment, baseline assessment, and randomization); (2) treatment phase (nine sessions, twice or thrice per week over 3−4 weeks; the HAL and control groups will perform gait treatment using HAL or CGT, respectively, and finally (3) post-treatment evaluation phase. The Functional Ambulation Category score will be the primary outcome measure, and the following secondary outcome measures will be assessed: Mini-Mental State Examination, Brunnstrom recovery stage of lower limbs, Fugl–Meyer assessment of lower limbs, 6-min walking distance, comfortable gait speed, step length, cadence, Barthel Index, Functional Independence Measure, gait posture, motion analysis (muscle activity), amount of activity (evaluated using an activity meter), stroke-specific QOL, and modified Rankin Scale score. The baseline assessment, post-treatment evaluation, and follow-up assessment will evaluate the overall outcome measures; for other evaluations, physical function evaluation centered on walking will be performed exclusively, excluding ADL and QOL scores. This study is a randomized controlled trial that aims to clarify the efficacy and safety of gait treatment using HAL compared with CGT in hemiplegic patients with acute stroke. In addition, we aim to establish a protocol for doctor-initiated clinical trials for acute stroke based on the study results. If our results demonstrate the effectiveness of the proposed treatment regarding outcomes of patients with hemiplegic acute stroke, this study will promote the treatment of these patients using the HAL system as an effective tool in future stroke rehabilitation programs. The study protocol was registered with the Japan Registry of Clinical Trials on October 14, 2020 (jRCTs032200151).

Influence of hybrid assistive limb gait training on spatial muscle activation patterns in spinal muscular atrophy type III

Background: Despite the potential benefits, the effects of Hybrid Assistive Limb (HAL) gait training on changes in neuromuscular activation that accompany functional gains in individuals with spinal muscular atrophy (SMA) type III is not well known. In this article, we quantify the effects of HAL gait training on spatial muscle activity patterns in a patient with SMA type III using multi-channel surface electromyography (SEMG). Methods: A 21-years old male (168 cm, 47.8 kg) with spinal muscular atrophy type III, when diagnosed at 18-years old by genetic screening, participated in this case study. Although he presented with forearm distal muscle weakness, atrophy of the intrinsic muscles of the hand, and neuromuscular fatigue, his activities of daily living is independent. The patient underwent a separate, single 33-minute session of both HAL and treadmill gait training. To evaluate the coefficient of variation (CoV) of force and alterations in the SEMG spatial distribution patterns, modified entropy and CoV of root mean square (RMS) were calculated from the vastus lateralis (VL) muscle before and after the intervention of HAL and treadmill gait training. Each training session was separated by a period of one month to avoid cross-over effects. Results: There was a greater decrease in the ΔCoV of force and an increase in the magnitude of whole VL muscle activation from pre-intervention to post-intervention with the HAL gait training as compared to the treadmill gait training. In response to only HAL gait training, the CoV of RMS was higher, and the modified entropy was lower post-intervention than pre-intervention. Conclusions: Our results support the notion that HAL gait training has a positive benefit on motor output not only in the magnitude of SEMG generated but also the patterns of neural activation.

Influence of hybrid assistive limb gait training on spatial muscle activation patterns in spinal muscular atrophy type III

Background: Despite the potential benefits, the effects of Hybrid Assistive Limb (HAL) gait training on changes in neuromuscular activation that accompany functional gains in individuals with spinal muscular atrophy (SMA) type III is not well known. In this article, we quantify the effects of HAL gait training on spatial muscle activity patterns in a patient with SMA type III using multi-channel surface electromyography (SEMG). Methods: A 21-years old male (168 cm, 47.8 kg) with spinal muscular atrophy type III, when diagnosed at 18-years old by genetic screening, participated in this case study. Although he presented with forearm distal muscle weakness, atrophy of the intrinsic muscles of the hand, and neuromuscular fatigue, his activities of daily living is independent. The patient underwent a separate, single 33-minute session of both HAL and treadmill gait training. To evaluate the coefficient of variation (CoV) of force and alterations in the SEMG spatial distribution patterns, modified entropy and CoV of root mean square (RMS) were calculated from the vastus lateralis (VL) muscle before and after the intervention of HAL and treadmill gait training. Each training session was separated by a period of one month to avoid cross-over effects. Results: There was a greater decrease in the ΔCoV of force and an increase in the magnitude of whole VL muscle activation from pre-intervention to post-intervention with the HAL gait training as compared to the treadmill gait training. In response to only HAL gait training, the CoV of RMS was higher, and the modified entropy was lower post-intervention than pre-intervention. Conclusions: Our results support the notion that HAL gait training has a positive benefit on motor output not only in the magnitude of SEMG generated but also the patterns of neural activation.

Adjustment effect during shoulder abduction training with the Hybrid Assistive Limb in a patient with postoperative C5 palsy

Standard shoulder rehabilitation procedures for patients with postoperative C5 palsy have not yet been established. We applied a wearable robot suit hybrid assistive limb (HAL) for a patient with postoperative C5 palsy and conducted shoulder abduction training with HAL. A 65-year-old woman was diagnosed with postoperative C5 palsy after undergoing cervical spine surgery. Five days after surgery, shoulder abduction training with HAL was initiated. The shoulder abduction angle and power and trapezius and deltoid activities were evaluated. Ten rehabilitation sessions were conducted until 82 days after surgery. Shoulder abduction training was safely and effectively performed from the first session. Her shoulder abduction angle and power improved at every session, and she could fully elevate her arm without any compensatory motion after the 10th session. Shoulder HAL training suppressed the muscular activity of the trapezius and activated that of the deltoid, especially in the earlier stages of rehabilitation. Moreover, it had an adjustment effect for obtaining normal shoulder motion, which might have promoted smoother arm elevation using errorless motor learning. These findings suggest that HAL is a useful tool for shoulder rehabilitation in patients with postoperative C5 palsy.

Influence of hybrid assistive limb gait training on spatial muscle activation patterns in spinal muscular atrophy type III.

Background: Despite the potential benefits, the effects of Hybrid Assistive Limb (HAL) gait training on changes in neuromuscular activation that accompany functional gains in individuals with spinal muscular atrophy (SMA) type III is not well known. In this article, we quantify the effects of HAL gait training on spatial muscle activity patterns in a patient with SMA type III using multi-channel surface electromyography (SEMG). Methods:A 21-years old male (168 cm, 47.8 kg) with spinal muscular atrophy type III, when diagnosed at 18-years old by genetic screening, participated in this case study. Although he presented with forearm distal muscle weakness, atrophy of the intrinsic muscles of the hand, and neuromuscular fatigue, his activities of daily living is independent. The patient underwent a separate, single 33-minute session of both HAL and treadmill gait training. To evaluate the coefficient of variation (CoV) of force and alterations in the SEMG spatial distribution patterns, modified entropy and CoV of root mean square (RMS) were calculated from the vastus lateralis (VL) muscle before and after the intervention of HAL and treadmill gait training. Each training session was separated by a period of one month to avoid cross-over effects. Results: There was a greater decrease in the ΔCoV of force and an increase in the magnitude of whole VL muscle activation from pre-intervention to post-intervention with the HAL gait training as compared to the treadmill gait training. In response to only HAL gait training, the CoV of RMS was higher, and the modified entropy was lower post-intervention than pre-intervention. Conclusions: Our results support the notion that HAL gait training has a positive benefit on motor output not only in the magnitude of SEMG generated but also the patterns of neural activation.

Effect of Training With the Hybrid Assistive Limb on Gait Cycle Kinematics After Total Knee Arthroplasty.

IntroductionReportedly, wearable robots, such as the hybrid assistive limb (HAL), are effective in the functional recovery of various locomotor disabilities, including disrupted walking, restricted range of motion, and muscle weakness. However, the effect of walking exercises with a HAL on the kinematic and kinetic variables of lower limb joint function is not yet fully understood. Therefore, the purpose of this study was to elucidate the effect of HAL on the kinematic and kinetic variables of lower limb function in patients 5 weeks after total knee arthroplasty (TKA).Materials and MethodsNine patients (ten knees) in the HAL training group and nine patients (nine knees) in the control group underwent TKA. HAL training was initiated 1–5 weeks after TKA, and general rehabilitation was performed in the control group. Gait analysis was performed on each patient using a motion analysis system at 5 weeks after TKA. We compared the effects of the joint angles of the walking cycle between groups, and investigated the effect of the walking cycle’s joint angles on step length.ResultsIn the HAL group, the odds ratio of hip extension was as large as 1.741, while that of knee swing was as large as 1.501. These 2 variables were significant between the 2 groups. Knee swing and varus significantly affected step length.ConclusionsOur results suggest that training by wearing HAL after TKA increased the mobility of the knee and hip joints during early postoperative walking, and that walking ability was improved by increasing the step length.

Efficacy of cardiac rehabilitation with motion assistance from wearable cyborg hybrid assistive limb in patients with chronic heart failure: a randomized controlled trial

Abstract Background Recent Cochrane Systematic Review suggested that the participation in cardiac rehabilitation is associated with approximately 20% lower cardiovascular mortality and morbidity. Exercise therapy is the key component of cardiac rehabilitation programs. In recent years, innovative technologies have been introduced into the field of rehabilitation, and a typical example is the wearable cyborg Hybrid Assistive Limb (HAL). The wearable cyborg HAL provides motion assistance based on detection of bioelectrical signals on the skin surface when muscle forces are generated. The lumbar-type HAL is expected to expand the therapeutic options for severe cardiac patients who have difficulty in performing usual cardiac rehabilitation programs, such as bicycle pedaling or walking. Purpose We aim to compare the efficacy of exercise therapy performed with motion assistance from a lumbar-type HAL versus conventional training (sit-to-stand exercise without HAL) in patients with chronic heart failure. Methods This clinical trial is a randomized, non-blinded, and controlled study. Twenty-eight heart failure patients (73.1±13.8 years) who have difficulty in walking at the usual walking speed of healthy subjects were randomly assigned to 2 groups (HAL group or control group) with a 1:1 allocation ratio and performed sit-to stand exercise either with HAL or without HAL for 5 to 30 minutes once a day, and 6 to 10 days during the study period. The brain natriuretic peptide (BNP), isometric knee extensor strength, standing ability (30-seconds chair-stand test: CS-30), short physical performance battery (SPPB) and 6-minute walking distance (6MWD) were measured before and after the completion of cardiac rehabilitation. Cardiac events such as death, re-hospitalization, myocardial infarction and worsening of angina pectoris and heart failure during 1 year after discharge were evaluated. Results There was no significant difference in the number of days of exercise therapy between the two groups. BNP, SPPB and 6MWD were improved in both groups. In the HAL group, the isometric knee extensor strength (0.29±0.11 vs 0.35±0.11 kgf/kg, p=0.003) significantly improved and CS-30 (5.5±5.1 vs 8.2±5.3, p=0.054) tended to improve. However, in the control group, either the isometric knee extensor strength (0.35±0.11 vs 0.36±0.14 kgf/kg, p=0.424) or CS-30 (6.0±4.3 vs 9.2±6.2, p=0.075) did not significantly change. HAL group showed significantly more improvement in the isometric knee extensor strength than control group (p=0.045). Cardiac events occurred in 20% in the HAL group and 43% in the control group. Conclusion The improvement in isometric knee extensor strength with the assistance from lumbar-type HAL suggests that exercise therapy using this device may be useful in chronic heart failure patients with flail or sarcopenia, a strong poor prognostic factor in these patients. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was supported in part by a grant-in-aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (JSPS KAKENHI grant number JP17K09485) and funded by the ImPACT Program of the Council for Science, Technology and Innovation (Cabinet Office, Government of Japan) (grant number 2017-PM05-03-01).

A randomized controlled study incorporating an electromechanical gait machine, the Hybrid Assistive Limb, in gait training of patients with severe limitations in walking in the subacute phase after stroke.

Early onset, intensive and repetitive, gait training may improve outcome after stroke but for patients with severe limitations in walking, rehabilitation is a challenge. The Hybrid Assistive Limb (HAL) is a gait machine that captures voluntary actions and support gait motions. Previous studies of HAL indicate beneficial effects on walking, but these results need to be confirmed in blinded, randomized controlled studies. This study aimed to explore effects of incorporating gait training with HAL as part of an inpatient rehabilitation program after stroke. Thirty-two subacute stroke patients with severe limitations in walking were randomized to incorporated HAL training (4 days/week for 4 weeks) or conventional gait training only. Blinded assessments were carried out at baseline, after the intervention, and at 6 months post stroke. The primary outcome was walking independence according to the Functional Ambulation Categories. Secondary outcomes were the Fugl-Meyer Assessment, 2-Minute Walk Test, Berg Balance Scale, and the Barthel Index. No significant between-group differences were found regarding any primary or secondary outcomes. At 6 months, two thirds of all patients were independent in walking. Prediction of independent walking at 6 months was not influenced by treatment group, but by age (OR 0.848, CI 0.719-0.998, p = 0.048). This study found no difference between groups for any outcomes despite the extra resources required for the HAL training, but highlights the substantial improvements in walking seen when evidence-based rehabilitation is provided to patients, with severe limitations in walking in the subacute stage after stroke. In future studies potential subgroups of patients who will benefit the most from electromechanically-assisted gait training should be explored.

Efficacy of Cardiac Rehabilitation with Assistance from Hybrid Assistive Limb in Patients with Chronic Heart Failure: Protocol for a Randomized Controlled Study

The hybrid assistive limb (HAL) provides motion assistance based on bioelectrical signals detected on the skin surface when muscle forces are generated. The lumbar-type HAL is expected to expand the therapeutic options for severe cardiac patients who have difficulty in moving on their own legs. We aim to compare the efficacy of exercise therapy performed with assistance from a lumbar-type HAL versus conventional training (sit-to-stand exercise without HAL) in patients with chronic heart failure. This investigation will be a randomized, nonblinded, controlled study. Sixty patients who satisfy the criteria to receive cardiac rehabilitation therapy under the Japanese national insurance system will be enrolled at the University of Tsukuba Hospital. Participants randomly assigned to 2 groups (HAL group and conventional group) at a 1:1 allocation ratio will perform exercise therapy either with HAL or without HAL for 5–30 min once a day for 6–10 days. Outcome parameters will be measured just before and after the completion of the exercise therapy and at 1 year after hospital discharge. The primary outcomes will be the heart rate, blood pressure, subjective ratings of exercise intensity during exercise (Borg scale), number of days from the start of exercise therapy to independent walking and to discharge, and prognosis (mortality and cardiovascular events) over the 1-year period after discharge. The secondary outcomes will be the assessment of heart failure severity, brain natriuretic peptide, grip strength, thigh muscle thickness, isometric knee extensor strength, standing ability, 10-meter walking speed, 6-min walking distance, short physical performance battery, and adverse events. Unpaired t tests will be used for baseline assessments and outcome measures. This is the first randomized controlled study to examine the efficacy and feasibility of lumbar-type HAL in patients with chronic heart failure. If the results confirm beneficial effects in the outcomes of patients with heart failure, this study will add more evidence in support of the use of the lumbar-type HAL as an effective tool in new cardiac rehabilitation programs.

A Randomized and Controlled Crossover Study Investigating the Improvement of Walking and Posture Functions in Chronic Stroke Patients Using HAL Exoskeleton - The HALESTRO Study (HAL-Exoskeleton STROke Study).

Background: The exoskeleton HAL (hybrid assistive limb) has proven to improve walking functions in spinal cord injury and chronic stroke patients when using it for body-weight supported treadmill training (BWSTT). Compared with other robotic devices, it offers the possibility to initiate movements actively. Previous studies on stroke patients did not compare HAL-BWSTT with conventional physiotherapy (CPT). Therefore, we performed a crossover clinical trial comparing CPT and HAL-BWSTT in chronic stroke patients with hemiparesis, the HALESTRO study. Our hypothesis was that HAL-training would have greater effects on walking and posture functions compared to a mixed-approach CPT.Methods: A total of 18 chronic stroke patients participated in this study. Treatment consisted of 30 CPT sessions and of 30 sessions of BWSTT with a double leg type HAL exoskeleton successively in a randomized, crossover study design. Primary outcome parameters were walking time and speed in 10-meter walk test (10MWT), time in timed-up-and-go test (TUG) and distance in 6-min walk test (6MWT). Secondary outcome parameters were the functional ambulatory categories (FAC) and the Berg-Balance Scale (BBS). Data were assessed at baseline, at crossover and at the end of the study, all without using and wearing HAL.Results: Our study demonstrate neither a significant difference in walking parameters nor in functional and balance parameters. When HAL-BWSTT was applied to naïve patients, it led to an improvement in walking parameters and in balance abilities. Pooling all data, we could show a significant effect in 10MWT, 6MWT, FAC and BBS, both therapies sequentially applied over 12 weeks. Thereby, FAC improve from dependent to independent category (3 to 4). One patient dropped out of the study due to intensive fatigue after each training session.Conclusion: HAL-BWSTT and mixed-approach CPT were effective therapies in chronic stroke patients. However, compared with CPT, HAL training with 30 sessions over 6 weeks was not more effective. The combination of both therapies led to an improvement of walking and balance functions. Robotic rehabilitation of walking disorders alone still lacks the proof of superiority in chronic stroke. Robotic treatment therapies and classical CPT rehabilitation concepts should be applied in an individualized therapy program.

Improvement and sustainability of walking ability with hybrid assistive limb training in a patient with cerebral palsy after puberty: a case report

[Purpose] Cerebral palsy is one of the most common causes of childhood physical disability affecting motor development. Gait training with a wearable-robot, such as the Hybrid Assistive Limb, has been reported to improve gait ability in patients with chronic motor disabilities; however, there are no reports concerning the sustained improvement of walking ability with its use in patients with cerebral palsy. We present our observations for the use of Hybrid Assistive Limb gait training in a postpubescent cerebral palsy patient. [Participant and Methods] A 17-year-old male with spastic cerebral palsy could only ambulate slightly using a crouch gait posture and with the aid of a walker. Hybrid Assistive Limb training was performed thrice weekly for 4 weeks (total of 12 sessions) along with concurrent daily physical therapy. The follow-up period was 7 months after the intervention. [Results] The intervention resulted in improvements in the patient’s gait speed, proportion of the stance phase in a gait cycle, step length, and the flexion angle of the knees at initial contact and during late stance phase, which was sustained for 7 months following the intervention. [Conclusion] Our observations suggest that Hybrid Assistive Limb training may effectively improve and sustain walking ability even among postpubescent cerebral palsy patients who have a decreased walking ability.

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

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.