Effects of visual biofeedback-based training on limits of stability and functional outcomes in subacute stroke patients

Introduction: Stroke is the second leading cause of death and major cause of long-term disability worldwide (GBD 2019 Stroke Collaborators, 2021). Impaired trunk control, postural asymmetry, and reduced sitting stability are common consequences of stroke that negatively affect mobility, balance, and independence in activities of daily living (ADL). Trunk control is considered a fundamental prerequisite for functional movement because it provides proximal stability necessary for coordinated limb activity during sitting, standing, and walking (Verheyden et al., 2006). Patients with hemiparesis frequently exhibit trunk asymmetry and reduced mobility on the affected side. Furthermore, sitting balance varies considerably during the early post-stroke phase; therefore, rehabilitation is essential for restoring motor and neurological function. Recent evidence suggests that sensory stimulation combined with task-oriented motor training may enhance post-stroke recovery by improving multisensory integration and postural control (Stanton et al., 2017). Visual biofeedback offers real-time information about body position and movement, facilitating active postural correction and motor learning. However, evidence regarding its effects on trunk symmetry and functional limits of stability during the subacute stage of stroke remains limited. Therefore, we aimed to evaluate the effects of visual biofeedback-based sensorimotor training on functional limits of stability during sitting and to determine the responsiveness of the Trunk Impairment Scale (TIS) and Stroke Impact Scale (SIS) to intervention-related changes in patients with subacute stroke.Methods: In this randomized controlled study, 40 subacute post-stroke inpatients (33 men, mean age 64.9 ± 11.1 years) were allocated to either an Experimental group receiving visual biofeedback-based postural training in a sitting position in addition to standard physiotherapy or to a Control group receiving standard physiotherapy alone. Biofeedback training was delivered using a specialized chair equipped with an integrated force platform and custom-designed training software. The intervention lasted 8 days. Participants in the Experimental group completed daily 15–20-minute training sessions comprising visually guided voluntary trunk tilts, vibration-induced perturbations, and combined sensorimotor tasks. Outcome measures included functional limits of stability during sitting, TIS scores of assessing trunk performance, and patient-reported outcomes assessed by the SIS, including domain-specific scores. All assessments were conducted before and after the intervention.Results: The Experimental group demonstrated significant improvements in functional limits of stability, with mean increases of 33 % on the paretic side and 28 % on the non-paretic side (both p < .001). Although both groups showed significant improvements in trunk control and overall functional status, gains were significantly greater in the Experimental group. The largest between-group differences were observed in total TIS score and in the SIS Mobility and ADL domains (Gábor et al., 2025). Furthermore, improvements in trunk mobility were strongly associated with better ADL performance.Conclusions: Improving trunk balance is essential for functional independence after stroke. Visual biofeedback-based training combined with proprioceptive stimulation effectively improved sitting stability and functional mobility in subacute stroke patients. Enhanced sensory input together with repetitive trunk-oriented exercises expanded the functional limits of stability and resulted in greater improvements than standard physiotherapy alone. The combined use of objective measures of sitting stability together with the TIS and the SIS provided a comprehensive evaluation of intervention-related changes relevant to post-stroke recovery and independence.Acknowledgements: Supported by VEGA 2/0098/25.