In this study, we developed a unilateral knee actuated exoskeletal gait orthosis (KAEGO) for hemiplegic patients to conduct gait training in real-world environments without spatial limitations. For this purpose, it is crucial that the controller interacts with the patient’s gait intentions. This study newly proposes a simple gait control strategy that detects the gait state and recognizes the patient’s gait intentions using only the motion information of the lower limbs obtained from an embedded inertial measurement units (IMU) sensor and a knee angle sensor without employing ground reaction force (GRF) sensors. In addition, a torque generation method based on negative damping was newly applied as a method to determine the appropriate amount of assistive torque to support flexion or extension movements of the knee joint. To validate the performance of the developed KAEGO and the effectiveness of our proposed gait control strategy, we conducted walking tests with a hemiplegic patient. These tests included verifying the accuracy of gait recognition and comparing the metabolic cost of transport (COT). The experimental results confirmed that our gait control approach effectively recognizes the patient’s gait intentions without GRF sensors and reduces the metabolic cost by approximately 8% compared to not wearing the device.

Gait training for paraplegic patients is effective in preventing various complications due to prolonged sitting. In these patients, the use of powered exoskeletal-gait-orthosis (EGO) consumes lower energy than traditional training methods using non-powered EGO, such as a reciprocating-gait-orthosis (RGO). Thus, long-term training is possible and effective in increasing the activity level of the trunk muscles. However, more than 60% of paraplegic patients have incomplete injuries with residual function, which is inversely related to the functional role of the orthosis. We hypothesized that the gait ability in incomplete paraplegia could be improved by knee joint activation, and we developed a lightweight knee-actuated EGO (KAEGO). We verified its effectiveness in one patient with an incomplete spinal cord injury by comparing the metabolic cost of transport (COT) measured by a six minute walk test to a traditional non-powered EGO. We found that with increasing assist torque to the knee joint, the COT decreased by up to 24.5%, and the gait performance, including walking speed and travel distance, significantly improved up to 37% compared to that of the non-powered EGO. Future studies should verify the KAEGO system’s effectiveness in a larger number of patients with various injury levels.

Reciprocating gait orthosis (RGO) is a traditional passive orthosis that provides postural stability and allows for independent upright ambulation with the assistance of walking aids, such as crutches, canes, and walkers. Previous follow-up studies of patients with RGOs have indicated a high frequency of nonusage. One of the main reasons for avoiding the use of RGOs is the excessive upper extremity loading induced by walking aids. The purpose of this study was to investigate the effect of hip actuation on the upper extremity loading induced by crutches when ambulating with an RGO. One female individual with a chronic complete spinal cord injury classified as ASIA A participated in this study. We compared the upper extremity loading during ambulation when individualized hip assistive forces were applied on the RGO (POWERED condition) and when wearing the RGO without actuation (RGO condition). Upper extremity loading was assessed by measuring the forces acting on the crutches. Compared with the RGO condition, the average upper extremity loading per unit distance and per unit time were lower for the POWERED condition by 15.21% (RGO: 0.307 ± 0.056 and POWERED: 0.260 ± 0.034 %bw·m${}^{-1}$) and by 21.19% (RGO: 0.120 ± 0.020 and POWERED: 0.094 ± 0.011 %bw·s${}^{-1}$), respectively. We believe that a substantial reduction in upper extremity loading during ambulation provided by hip actuation holds promise to promote long-term RGO use and enable patients with paraplegia to perform frequent and intensive rehabilitation training. As this is a single case study, subsequent studies should aim to verify this effect through a higher number of patients and to different injury levels.

Gait impairment is one of the most disabling consequences of stroke and substantially limits functional independence. While traditional orthoses provide joint stabilization, they often restrict natural motion and lack adaptive support. This study is aimed at evaluating the short‐term effects of an electric knee–ankle–foot orthosis (E‐KAFO) on gait performance and energy efficiency in patients with hemiplegia and at assessing how baseline balance ability, measured using the Berg Balance Scale (BBS), influences outcomes. This pre–post intervention, nonrandomized study enrolled poststroke survivors ( n = 22), who were stratified into high‐ (BBS > 45) and low‐ (BBS ≤ 45) balance groups (HBG and LBG, respectively). Participants underwent gait assessments under two conditions: body‐powered condition (BP_C), to evaluate rehabilitation effects independently of the device, and E‐KAFO_C, to assess short‐term assistive efficacy immediately after device use. All assessments were conducted before and after a 3‐week intervention comprising seven E‐KAFO training sessions. The primary outcome was gait speed, measured using the 5‐m walk test (5‐mWT). The 3‐min and 6‐min walk tests (3‐MWT and 6‐MWT) and the physiological cost index (PCI) were also evaluated to assess gait endurance and energy efficiency. The 5‐mWT and 3‐MWT/6‐MWT were performed in randomized order to minimize order‐related bias. No standard rehabilitation‐only control group was included. Assistive effects (E‐KAFO_C) and rehabilitative effects (BP_C) were analyzed and reported separately. Two‐way repeated measures analysis of variance was used to assess the effects of group, time, and their interaction. Significant improvements in gait speed and endurance were observed across both conditions, with the LBG showing greater relative gains postintervention. In the E‐KAFO_C condition, the LBG demonstrated a 33.31% increase in 5‐mWT speed and a 25.51% increase in 3‐MWT distance. Notably, PCI decreased in both groups, although the reduction was significant only in the LBG. These findings underscore the distinction between the short‐term assistive benefits of the E‐KAFO and the rehabilitative improvements captured by BP_C outcomes, emphasizing that BP_C results serve as the primary indicator of rehabilitation effectiveness. Importantly, baseline balance ability assessed by the BBS influenced assistive and rehabilitative responses, supporting its relevance for patient stratification. Given the exploratory design and limited sample size, these findings are hypothesis‐generating and require confirmation in larger randomized controlled trials. Trial Registration: WHO International Clinical Trials Registry Platform, supported by the Korea Disease Control and Prevention Agency (KDCA): KCT0011412