The Potential of Robotic-Assisted Gait Training in a Rehabilitation Setting

Stroke is the most common cause of physical disability in Western industrialized countries, with approximately 70% of patients experiencing moderate to severe physical impairments [1]. In addition to the negative impact on mobility and balance, activities of daily living are often affected [2]. In particular, gait impairments-manifested, for example, by reduced walking speed or shortened step length-can significantly reduce the quality of life of patients after stroke [2,3]. Therefore, the restoration of a physiological gait pattern in terms of both qualitative and quantitative parameters represents a key objective of post-stroke rehabilitation.

In addition to conventional therapeutic approaches, robotic-assisted gait training (RAGT) devices such as the Lokomat® are frequently used [4]. With this device, patients are able to walk actively on a treadmill while being supported by an exoskeleton that simulates a symmetrical, bilateral gait pattern [3]. RAGT devices aim to improve walking by enabling a high number of repetitions of task-oriented movements, thereby facilitating the relearning of movement patterns [5].

Novel technologies such as the functional proprioceptive stimulation (FPS) device Vibramoov® may have the potential to enhance the effectiveness of RAGT. This therapeutic device aims to stimulate proprioceptors located at the muscle-tendon junction through targeted vibratory stimuli, thereby activating sensorimotor centers in the brain via afferent Ia fibers [6]. As a result, the execution of movements-for example during walking-may be facilitated. According to the manufacturer, Vibramoov® can be used during walking on level ground, during treadmill walking, or in combination with the Lokomat®. However, to date there is no research investigating the effects of Vibramoov® on gait parameters in stroke patients undergoing inpatient rehabilitation.

The aim of the present study is therefore to contribute to the investigation of FPS as a potential approach to maximize the effectiveness of RAGT. The primary research question is: Does Lokomat® training combined with the Vibramoov® device have a greater effect on qualitative and quantitative gait parameters in patients after stroke compared with Lokomat® training alone? To address this research question, a randomized controlled trial will be conducted at the Gröbming Rehabilitation Center. Patients after stroke who are undergoing a four-week neurological inpatient rehabilitation program will be randomly assigned to either an intervention group or a control group. Based on data regarding the effect of RAGT on the 6-Minute Walk Test (6MWT), and accounting for potential dropouts, a sample size of 20 patients per group was calculated [4].

Patients in both groups will receive the conventional rehabilitation program according to the medical service profile, in which RAGT represents part of the standard treatment for stroke patients with gait impairments. Patients in the control group will perform RAGT using the Lokomat®, while patients in the intervention group will perform RAGT using the Lokomat® in combination with Vibramoov®. The extent of RAGT will be identical in both groups.

The effects of the intervention will be quantified using several outcome parameters, including the 6-Minute Walk Test (6MWT) and spatiotemporal gait parameters. In addition, various functional scores and patient-reported outcome measures will be collected, and laboratory parameters and blood biomarkers will be analyzed. Depending on the distribution of the data, standard statistical methods such as the independent t-test or the Mann-Whitney U test will be applied to address the research question. A follow-up assessment six months after completion of the study (telephone interview) evaluating EQ-5D and PHQ-4 is planned.

Inclusion criteria

• Diagnosis of stroke (ischemic or hemorrhagic) ≥ 3 months
• Age ≥ 18a and ≤ 80a
• 6MWT ≤ 200m
• Barthel Index ≤ 95
• Mini Mental State Exam (MMSE) ≥ 24
• FAC: ≤ 4
• BBS): ≤49
• Modified Ashworth Scale (MAS): 0-3 for the lower extremity

Exclusion criteria

• The presence of any comorbidity or disability other than stroke that would preclude gait training
• Any uncontrolled health condition for which exercise is contraindicated