Systematic review on wearable lower-limb exoskeletons for gait training in neuromuscular impairments

Abstract

Gait disorders can reduce the quality of life for people with neuromuscular impairments. Therefore, walking recovery is one of the main priorities for counteracting sedentary lifestyle, reducing secondary health conditions and restoring legged mobility. At present, wearable powered lower-limb exoskeletons are emerging as a revolutionary technology for robotic gait rehabilitation. This systematic review provides a comprehensive overview on wearable lower-limb exoskeletons for people with neuromuscular impairments, addressing the following three questions: (1) what is the current technological status of wearable lower-limb exoskeletons for gait rehabilitation?, (2) what is the methodology used in the clinical validations of wearable lower-limb exoskeletons?, and (3) what are the benefits and current evidence on clinical efficacy of wearable lower-limb exoskeletons? We analyzed 87 clinical studies focusing on both device technology (e.g., actuators, sensors, structure) and clinical aspects (e.g., training protocol, outcome measures, patient impairments), and make available the database with all the compiled information. The results of the literature survey reveal that wearable exoskeletons have potential for a number of applications including early rehabilitation, promoting physical exercise, and carrying out daily living activities both at home and the community. Likewise, wearable exoskeletons may improve mobility and independence in non-ambulatory people, and may reduce secondary health conditions related to sedentariness, with all the advantages that this entails. However, the use of this technology is still limited by heavy and bulky devices, which require supervision and the use of walking aids. In addition, evidence supporting their benefits is still limited to short-intervention trials with few participants and diversity among their clinical protocols. Wearable lower-limb exoskeletons for gait rehabilitation are still in their early stages of development and randomized control trials are needed to demonstrate their clinical efficacy.

The Muscle Fatigue’s Effects on the sEMG-Based Gait Phase Classification: An Experimental Study and a Novel Training Strategy

“…The practical applications of the gait phase classifiers in wearable robots demand a deeper understanding of the relationship between muscle fatigue and the classifiers' performance. Our study mainly performs the following three aspects of work: (1) A quantitative investigation on the impact of muscle fatigue on the performance of the classifiers using different features; (2) a training strategy that improves the robustness of the classifiers against the fatigue; (3) a statistical analysis to interpret the phenomena of the classification. These works can provide a reference for other studies, such as designing the robust human-machine interface and investigating muscle fatigue-induced sEMG changes.…”

“…In this way, we try to determine how much muscle fatigue affects the gait classifiers and which classifier performs better under the fatigue. (2) The first half of the data of session 3 is added into the training set, and the rest of the data is used as the test set. In this way, we propose the training strategy that aims to improve the performances of the classifiers under the fatigue condition.…”

“…Lower-limb wearable robots, a kind of powered device that can enhance the mobility of the human body, have been widely used for assistive and rehabilitative purposes in recent years [1][2][3]. Regarding the control of wearable robots, surface Electromyography (sEMG) provides an intuitive signal source that can directly reflect users' motion intent, and thus, can assist in involving the active participation of users [4][5][6][7].…”

Wearable Robotic Gait Training in Persons with Multiple Sclerosis: A Satisfaction Study

“…Neurorehabilitation can help improve gait disturbances using different approaches, such as robot-assisted therapy which has been recently developed and is now being implemented in rehabilitation services [ 3 ]. The use of exoskeletons provides some benefits compared to conventional therapy, such as the possibility to reproduce physiological gait patters and to allow for more intensive therapy with more number of repetitions, maximizing time and decreasing the effort for both patient and therapist.…”

“…There are two kinds of exoskeletons: grounded exoskeletons, which allow to walk on a treadmill, or over-ground wearable exoskeletons [ 3 ]. Regarding MS, there are only a few studies that analyse the effects of gait training using exoskeletons, and most of them have been carried out with fixed exoskeletons.…”