Biomechanical Task-Based Gait Analysis Suggests ReWalk Gait Resembles Crutch Gait

Abstract

Current gait rehabilitation strategies rely heavily on motor learning principles, which involve facilitating active patient participation, high-doses of biomechanical task-related motor activities and accurate feedback. Furthermore, appropriate muscle groups need to be recruited for the joint movements that constitute the biomechanical task-related activities in order to effectively promote motor learning. Recently, exoskeleton-type robots utilizing crutches have been incorporated into overground gait rehabilitation programs. However, it is unclear which gait-related tasks are being trained because the joint movements and muscle recruitment patterns deviate from those of natural gait. This raises concerns because repetitive training with these devices may not lead to desirable rehabilitative gains. In this study, we compare the lower limb joint angles and electromyography patterns of healthy subjects walking with and without ReWalk in accordance with the three major biomechanical tasks required by bipedal gait: weight acceptance (WA), single-limb support, and limb advancement. Furthermore, we investigate whether the physical constraints of ReWalk, most noticeably the use of crutches and fixed ankle joints, were responsible for the specific changes by conducting additional walking sessions with either crutches or ankle foot orthoses. The results from the six healthy male volunteers suggest that the gait patterns observed with ReWalk deviate significantly from those of natural gait, particularly during the WA, and closely resemble those of crutch gait.

Investigation with able-bodied subjects suggests Myosuit may potentially serve as a stair ascent training robot

“…To address our observations in more detail, firstly, it is vital that we point out that the preservation of the user’s natural patterns suggest that Myosuit does not impede with the user’s natural movements. Often, when interventions are introduced, addition of new or exclusion of existing movements occurs 45 , 47 . When extensive training with these interventions is performed, non-physiological detrimental patterns may be habitualized 64 – 66 .…”

“…The knee, hip, and ankle joint sagittal angles were estimated as described in our previous work 45 , 50 , which is based on the method presented by Saito et al 57 . The relative angle of the estimated 3D orientation data, provided via the IMU sensors (74 Hz) via Delsys Trigno Wireless system, of the bones that make up the joint was used to estimate the joint angles.…”

“…However, the lack of volitional movement and non-physiological sensory feedback of the foot have been identified to be responsible for the lackluster results 36 , 43 , 44 . Furthermore, the high inertia of the devices elicits unwanted non-physiological muscle activation patterns 43 , 45 – 47 . On a bright note, a recent study by Bannwart et al demonstrated that a ceiling mounted robotic body weight support system could be potentially used as a stair ascent training device by showing that the task demand was reduced, evident by decreased EMG levels, while not affecting the user’s natural kinematics 9 .…”

A Proof of Principle Study Conducted by Community-Dwelling Seniors Using a Novel Passive Gait Assist System

“…However, studies have shown that full-bodyweight-supporting robot-assisted gait training (RAGT) exhibits lackluster rehabilitative efficacy [20][21][22]. The primary reason behind this is thought to be due to the lack of patient participation [23][24][25]. In order to resolve this issue, more recently, various wearable robots have been incorporated into the exercise regimen [26][27][28][29].…”

“…While there exists a plethora of assistive devices, simple rollators do not provide any force or trajectory assistance, and it has been reported that RAGT devices restrict free movement and have an inherent difficulty in providing assist-as-needed control [24,25]. Unpowered exosuits and devices consisting of only passive elements and no actuators have become a popular research topic [37][38][39][40][41].…”