Safety, Feasibility, and Efficacy of the Lumbar Type Hybrid Assistive Limb with Brain Injury-Related Lower Limb Hemiparesis in the Acute Phase: A Pilot Randomized Crossover Trial.

PurposeThis study aimed to investigate the safety, feasibility, and effect on hemiparetic muscle activity during sit-to-stand exercises using the lumbar type HAL in patients with acute-phase lower limb hemiparesis caused by ischemic stroke, cerebral hemorrhage, or postoperative brain tumor.MethodsThis randomized crossover study included twelve participants (ischemic stroke: 6, cerebral hemorrhage: 2, brain tumor: 4) for part 1, which assessed safety and comfort of sit-to-stand exercise using HAL, and ten participants (ischemic stroke: 4, cerebral hemorrhage: 3, brain tumor: 3) for part 2, which investigated the effect of HAL on muscle activities during sit-to-stand exercises. Participants performed either five sets (part 1) or a single set (part 2) of ten repetitions of sit-to-stand exercises under two conditions: with and without HAL assistance. Outcome included vital signs (blood pressure, heart rate, and percutaneous oxygen saturation), fatigue level in part 1. Muscle activity of bilateral gluteus maximus, biceps femoris, and vastus lateralis during the exercises were assessed in part 2. Outcomes were compared between the two conditions.ResultsThe results demonstrated that there were no significant changes in vital signs and fatigue between two conditions. Furthermore, HAL effectively increased muscle activity (μV) in the hemiparetic side vastus lateralis during the exercises (median, quartile range: 101.1, 55.8-125.9 vs. 79.9, 52.0-103.3, p = 0.03).ConclusionsThese findings suggest that the lumbar type HAL can be safely and feasibly used in patients with acute brain injury-related lower limb paresis, with potential effects on hemiparetic muscle activation. However, these results should be interpreted cautiously as exploratory observations.Registry informationClinical utility of cybernic system for patients with neurological diseases causing who need comprehensive nursing care (Clinical utility of cybernic system for patients with neurological diseases causing who need comprehensive nursing care (CUCSPND)), https://jrct.niph.go.jp/en-latest-detail/jRCTs052180074, jRCTs052180074.The effect of motor therapy using robot suit HAL for the patients with damaged brain (motor therapy using robot suit HAL), https://jrct.niph.go.jp/en-latestdetail/jRCTs052180223, jRCTs052180223.