Application of electromyographic biofeedback therapy in physical dysfunction rehabilitation and post-stroke anxiety reduction in stroke survivors

Abstract

BACKGROUND

Stroke is a leading cause of long-term disability worldwide, and limb motor dysfunction is one of the most common complications affecting the quality of life of patients.

AIM

To investigate the rehabilitation effects of conventional rehabilitation training combined with electromyographic biofeedback therapy on limb motor dysfunction in stroke survivors.

METHODS

This observational retrospective cohort study included 60 stroke survivors who underwent post-stroke rehabilitation training in the rehabilitation department of Qilu Hospital of Shandong University (Qingdao) from May 2023 to July 2024. The medical records of the patients were assessed. Eligible patients (N = 60) were divided into two groups on the basis of the type of rehabilitation training received: Conventional rehabilitation alone (control group, n = 30) and conventional rehabilitation combined with electromyographic biofeedback therapy (biofeedback group, n = 30). Upper and lower limb motor function, wrist extension, balance ability, and ankle dorsiflexion range of motion were evaluated before treatment and at 4 weeks and 8 weeks post-treatment by reviewing the patients’ electronic medical records.

RESULTS

At 4 weeks and 8 weeks post-treatment, the biofeedback group showed significantly better Fugl-Meyer assessment scores, Hospital Anxiety and Depression Scale scores, Hamilton Depression Rating Scale scores, Hamilton Anxiety Rating Scale scores, and wrist and ankle active range of motion scores than the control group.

CONCLUSION

Electromyographic biofeedback therapy combined with conventional rehabilitation can effectively improve upper and lower limb motor function, balance ability, activities of daily living, wrist extension, and ankle dorsiflexion dysfunction in patients post-stroke, with better efficacy than conventional rehabilitation alone.

Key Words: Stroke; Electromyographic biofeedback; Hemiplegia; Motor disorders; Rehabilitation

Core Tip: This study evaluates the effectiveness of electromyographic biofeedback therapy combined with conventional rehabilitation in post-stroke limb motor dysfunction and anxiety reduction. Patients (N = 60) were divided into control (conventional rehabilitation only) and biofeedback groups. Assessments included the Fugl-Meyer assessment, Hospital Anxiety and Depression Scale, Hamilton Depression Rating Scale, and Hamilton Anxiety Rating Scale. Results showed significant improvements in motor function and reduced anxiety in the biofeedback group compared to controls, highlighting the potential of this combined approach to enhance recovery outcomes in stroke patients.

INTRODUCTION

Stroke is a common neurological disorder characterized by rapid brain function impairment caused by insufficient blood supply to the spinal cord and brain or vascular obstruction leading to vascular rupture[1]. It is associated with high incidence, mortality, and disability rates[2]. In China, the prevalence of stroke is approximately 0.12%-0.18%, with over 2 million new cases reported annually. Stroke is considered one of the top three fatal diseases alongside cardiovascular diseases and malignant tumors[3]. With the advancements in medical and healthcare technologies, the treatment of stroke has significantly improved, leading to a notable reduction in mortality rates. However, up to 70%-80% of stroke survivors still experience varying degrees of disabilities such as swallowing difficulties and reading impairments[4]. Patients with limb motor dysfunction struggle to perform fine motor tasks due to their impairments, which disrupt their ability to care for themselves in daily life. The relationship between physical disability and psychological well-being is complex and bidirectional. Physical limitations can exacerbate feelings of helplessness and frustration, which, in turn, may lead to increased anxiety and depressive symptoms. Conversely, negative emotional states can hinder rehabilitation progress and reduce overall treatment efficacy. Consequently, these patients are prone to severe conditions like depression, irritability, and other mental disorders[5]. Addressing both physical and psychological aspects is crucial for comprehensive recovery. The recovery of paralyzed muscle function and strength post-stroke determines the quality of life for patients. Various rehabilitation methods for post-stroke functional impairments have shown efficacy through the synergistic effects of multiple approaches[6]. Acute stroke survivors should receive standard medications to reduce intracranial pressure, protect the brain, provide neural nutrition, and obtain anti-inflammatory effects[7].

Once patients’ vital signs stabilize and their condition becomes manageable, prompt initiation of routine rehabilitation training is essential to enhance muscle strength and improve limb movement and coordination skills, primarily utilizing neurodevelopmental techniques such as the Bobath method, the Brunnstrom method, proprioceptive neuromuscular facilitation, and motor relearning[8]. However, the treatment process of these methods is lengthy, with slow effects, often leading to anxiety and resistance in most patients. Electromyographic biofeedback therapy, used in muscle feedback therapy since the 1960s, is a safe, noninvasive treatment combining biofeedback and electrical stimulation[9]. The principle of electromyographic biofeedback therapy is related to the plasticity of the brain and nerves. After central nervous system damage, the damaged neurons cannot regenerate, but restructuring can occur to some extent through axonal sprouting, changes in axonal ion channels, and synaptic efficiency[10]. Furthermore, electromyographic biofeedback aids in establishing new conditioned reflex circuits between the brain and limbs to replace damaged internal feedback loops. However, the application of conventional rehabilitation combined with electromyographic biofeedback therapy in addressing limb motor dysfunction in stroke survivors is not yet well understood[11]. The present study aimed to elucidate the effect of conventional rehabilitation combined with electromyographic biofeedback therapy on the recovery of limb motor dysfunction in stroke survivors.

MATERIALS AND METHODS

Study design and patients

This retrospective study analysis included 60 stroke survivors who underwent post-stroke rehabilitation training at the rehabilitation department of Qilu Hospital of Shandong University (Qingdao) from May 2023 to July 2024. Patient medical records were evaluated. The inclusion criteria comprised patients with unilateral limb paralysis receiving rehabilitation training and/or electromyographic biofeedback therapy in the department. The exclusion criteria included patients with cognitive impairments, those with severe aphasia, and those who were unable to cooperate or communicate. During the study phase, 136 patients who underwent post-stroke rehabilitation training in the rehabilitation department met the inclusion criteria. Among them, 76 patients had incomplete clinical data. Ultimately, 60 participants were included in this analysis. The patients’ basic information and clinical backgrounds were obtained from the electronic medical record system. The eligible patients (N = 60) were divided into two groups on the basis of the type of rehabilitation training received: Conventional rehabilitation alone (control group, n = 30) and conventional rehabilitation combined with electromyographic biofeedback therapy (biofeedback group, n = 30). This study was approved by the Ethics Committee of Qilu Hospital of Shandong University (Qingdao, No. KYLL-KS-2024195), and the Ethics Committee agreed to waive informed consent.

Data collection

The preoperative information of eligible patients, including gender, age, weight, height, course of disease, nature and location of lesions, Fugl-Meyer assessment (FMA) scores for upper and lower limbs, Berg Balance Scale scores, activities of daily living (ADL) scores, wrist joint active range of motion (AROM, °), ankle joint AROM (°), and balance ability, were collected from the patient records. Postoperative data, including FMA scores for upper and lower limbs and wrist and ankle joint ROM, were obtained from the medical records.

Assessment scale

Depression levels were evaluated using the Hamilton Depression Rating Scale (HAMD), whereas anxiety was gauged using the Hamilton Anxiety Rating Scale (HAMA)[12,13]. HAMD and HAMA, both developed by Hamilton in 1960, serve as tools for measuring depressive and anxious symptoms, respectively. Each questionnaire contains 17 items, with individual item scores ranging between 0 and 2 or 0 and 4. A cumulative score of 7 or below signifies normal conditions; scores above this threshold indicate varying degrees of symptom severity: 8-17 suggests mild symptoms, 18-24 points to moderate symptoms, and a score of 25 or higher denotes severe depression or anxiety. The Hospital Anxiety and Depression Scale (HADS) consists of 14 items, measuring anxiety and depression dimensions separately. The scale uses a 4-point scoring system, with a total score ranging from 0 to 21 for each dimension. A threshold of 8 points indicates anxiety or depression, with scores above 8 indicating the presence of anxiety or depression. The total score for anxiety and depression ranges from 0 to 42, with higher scores indicating more severe levels of anxiety and depression.

Statistical analysis

All data were analyzed using SPSS (version 25.0) statistical software. Continuous data are presented as mean ± SD. For non-normally distributed data, the Wilcoxon rank-sum test was applied, and the results were presented as [median (25% quartile, 75% quartile)]. One-way analysis of variance was used to compare the homogeneity of variance and/or normally distributed data. The χ² test was employed for comparing count data. P < 0.05 was considered statistically significant.

RESULTS

Characteristics of the two groups

No significant differences were observed in the demographic and clinical information between the two groups (all P > 0.05, Table 1). Prior to treatment, no significant differences were found between the two groups in terms of movement, balance, ADL, and joint range of motion (all P > 0.05, Table 2).

Table 1 Comparison of demographic and clinical data between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Gender			0.795
Male	16	17
Female	14	13
Age (years)	60.07 ± 9.57	59.80 ± 10.05	0.917
Weight (kg)	73.27 ± 3.45	75.18 ± 4.06	0.054
Height (cm)	167.69 ± 8.94	168.75 ± 9.32	0.653
Duration (days)	17.33 ± 5.80	17.63 ± 6.22	0.847
Disease			0.795
Hemorrhage	13	14
Infarction	17	16
Disease			0.793
Left	18	17
Right	12	13

Table 2 Comparison of pre-treatment scores for movement, balance, activities of daily living, and joint range of motion between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
FMA (upper limb) score	15.5 (15,16)	15 (14,16)	0.237
FMA (lower limb) score	10 (9,11)	10 (9,11)	0.717
Berg score	11.23 ± 3.68	11.27 ± 3.54	0.972
ADL score	41.77 ± 11.17	40.67 ± 10.14	0.691
Wrist joint AROM (°)	22.33 ± 5.52	21.20 ± 6.30	0.462
Ankle joint AROM (°)	21.33 ± 5.65	21.17 ± 5.58	0.909

FMA: Fugl-Meyer assessment; ADL: Activities of daily living; AROM: Ankle active range of motion.

Comparison of upper limb motor function

The patient records indicated that upper limb motor function was assessed using the FMA scoring system. No significant differences were found in the pre-treatment FMA scores between the two groups. However, at 4 weeks and 8 weeks post-treatment, the upper limb motor function in the electromyographic biofeedback group was significantly superior to that of the control group (both P < 0.01), as shown in Table 3 and Figure 1A.

Figure 1 Comparison of motor function, motion range, balance ability, anxiety and depression between the two groups. A: Comparison of pre- and post-treatment upper limb Fugl-Meyer assessment scores between the two groups; B: Comparison of pre- and post-treatment lower limb Fugl-Meyer assessment scores between the two groups; C: Comparison of wrist joint range of motion before and after treatment between the two groups; D: Comparison of ankle joint range of motion before and after treatment between the two groups; E: Comparison of balance ability (Berg scores) before and after treatment between the two groups; F: Comparison of Hospital Anxiety and Depression Scale scores before and after treatment between the two groups; G: Comparison of Hamilton Depression Rating Scale scores before and after treatment between the two groups; H: Comparison of Hamilton Anxiety Rating Scale scores before and after treatment between the two groups. ^aP < 0.01 compared to the control group; ^bP < 0.001 compared to the control group. FMA: Fugl-Meyer assessment; EMG: Electromyographic; HADS: Hospital Anxiety and Depression Scale; HAMD: Hamilton Depression Rating Scale; HAMA: Hamilton Anxiety Rating Scale.

Table 3 Comparison of pre- and post-treatment upper limb Fugl-Meyer assessment scores.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	14.87 ± 0.90	14.73 ± 0.98	0.585
4 weeks after treatment	23.57 ± 2.16	25.30 ± 1.90	0.002
8 weeks after treatment	29.50 ± 1.63	36.83 ± 0.83	< 0.001

Comparison of lower limb motor function

The patient’s records indicated that lower limb motor function was evaluated using the FMA scoring system, with a total score of 34 points. Prior to treatment, the lower limb motor function between the two groups did not significantly differ (P > 0.05). However, compared with the control group, the electromyographic biofeedback group showed a significant increase in lower limb motor function at 4 weeks and 8 weeks post-treatment (P < 0.001, Table 4 and Figure 1B).

Table 4 Comparison of pre- and post-treatment lower limb Fugl-Meyer assessment scores.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	10.37 ± 1.43	9.87 ± 1.91	0.255
4 weeks after treatment	17.43 ± 1.92	20.20 ± 1.75	< 0.001
8 weeks after treatment	22.53 ± 3.34	26.73 ± 3.50	< 0.001

Comparison of maximum active wrist extension range

The patient records indicated that the maximum active extension range of the wrist was assessed using a goniometer. Prior to treatment, AROM did not significantly differ between the two groups (P > 0.05). However, compared with the control group, the electromyographic biofeedback group showed enhanced wrist AROM at 4 weeks and 8 weeks post-treatment (both P < 0.001, Table 5 and Figure 1C).

Table 5 Comparison of wrist joint range of motion before and after treatment between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	22.33 ± 5.52	21.20 ± 6.30	0.462
4 weeks after treatment	35.13 ± 7.57	42.30 ± 7.23	< 0.001
8 weeks after treatment	50.30 ± 8.45	59.43 ± 7.93	< 0.001

Comparison of maximum active ankle dorsiflexion before and after treatment in the two groups

The change in maximum active dorsiflexion of the ankle before and after treatment was investigated for both groups. Prior to treatment, no significant differences were observed in the ankle joint range of motion between the two groups (P > 0.05). However, compared with the control group, the electromyographic biofeedback group showed increased ankle joint range of motion at 4 weeks and 8 weeks post-treatment (both P < 0.001, Table 6 and Figure 1D).

Table 6 Comparison of ankle joint range of motion before and after treatment between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	21.33 ± 5.65	21.17 ± 5.58	0.909
4 weeks after treatment	32.30 ± 7.94	41.47 ± 7.31	< 0.001
8 weeks after treatment	47.20 ± 8.90	57.80 ± 8.19	< 0.001

Comparison of balance ability before and after treatment in the two groups

The patient records indicated that balance ability was evaluated using Berg Balance Scale scores. The balance ability of the electromyographic biofeedback group was significantly better than that of the control group at 4 weeks and 8 weeks post-treatment (both P < 0.001, Table 7 and Figure 1E).

Table 7 Comparison of balance ability before and after treatment between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	11.43 ± 2.57	11.53 ± 1.91	0.865
4 weeks after treatment	23.97 ± 2.28	27.97 ± 5.18	< 0.001
8 weeks after treatment	31.53 ± 1.28	39.87 ± 1.41	< 0.001

Comparison of anxiety and depression scores before and after treatment in the two groups

The anxiety and depression levels were assessed using HADS. Prior to treatment, no significant differences were found in the HADS scores between the two groups (P > 0.05). However, at 4 weeks and 8 weeks post-treatment, the HADS scores in the electromyographic biofeedback group significantly decreased compared with those in the control group (both P < 0.001), indicating that electromyographic biofeedback can improve post-stroke anxiety in stroke survivors (Table 8 and Figure 1F). The evaluation of depression levels by using HAMD showed no significant difference between the two groups before treatment (P > 0.05). At 4 weeks post-treatment, the electromyographic biofeedback group had a significantly lower HAMD score than the control group (P = 0.006). This difference was more pronounced at 8 weeks (P = 0.001). The results indicate that electromyographic biofeedback therapy was more effective in reducing depressive symptoms than the control treatment (Table 9 and Figure 1G).

Table 8 Comparison of Hospital Anxiety and Depression Scale scores before and after treatment between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	23.50 ± 2.29	23.57 ± 1.38	0.892
4 weeks after treatment	18.57 ± 2.28	10.97 ± 2.17	< 0.001
8 weeks after treatment	13.77 ± 2.70	6.33 ± 2.19	< 0.001

Table 9 Comparison of Hamilton Depression Rating Scale scores before and after treatment between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	22.63 ± 3.43	21.57 ± 3.35	0.228
4 weeks after treatment	13.43 ± 2.30	11.70 ± 2.38	0.006
8 weeks after treatment	9.87 ± 2.40	7.70 ± 2.52	0.001

HAMA was used to assess the anxiety levels before and after treatment. Initially, no significant difference was observed between the two groups (P > 0.05). However, at 4 weeks post-treatment, the electromyographic biofeedback group showed significantly lower HAMA scores than the control group (P = 0.009). This significant difference was further observed at 8 weeks post-treatment (P = 0.006). The results suggest that electromyographic biofeedback therapy was more effective in reducing anxiety symptoms than the control treatment during the study period (Table 10 and Figure 1H).

Table 10 Comparison of Hamilton Anxiety Rating Scale scores before and after treatment between the two groups.

	Control (n = 30)	Electromyographic biofeedback (n = 30)	P value
Before	20.83 ± 4.81	19.57 ± 4.76	0.309
4 weeks after treatment	14.03 ± 2.40	12.17 ± 2.84	0.009
8 weeks after treatment	9.73 ± 2.52	7.93 ± 2.39	0.006

DISCUSSION

With the advancement of modern medicine and diagnostic technologies, the mortality rate of stroke has significantly decreased, but the disability rate remains high[14]. Approximately 50% of surviving patients experience varying degrees of motor dysfunction, with limb paralysis being the most common form[15]. Patients with mild hemiplegia often exhibit a gait pattern characterized by flexed upper limbs, extended lower limbs, and a hemiplegic gait in circular motion. Those with complete paralysis are bedridden, which considerably affects their ADL[16]. Motor dysfunction primarily involves the loss of control by the higher cerebral centers over the lower centers, leading to abnormalities in muscle tone, movement patterns, poor muscle coordination, and improper weight distribution, thereby causing considerable inconvenience in the daily life of patients[17]. Obtaining an effective method to treat the sequelae of stroke has become a crucial task in medicine. The principles of stroke rehabilitation emphasize early intervention[18]. Early rehabilitation training aids in reducing complications and improving the acute prognosis of patients[19].

Most stroke survivors experience some degree of functional impairment, with limb motor dysfunction being the most common. Lower limb dysfunctions, such as foot drop, inversion, and circumduction, remarkably affect the walking ability and rehabilitation confidence of patients[20]. The current primary rehabilitation methods for limb paralysis include neuropharmacological therapy, early rehabilitation training, ankle-foot orthoses, body weight-supported treadmill training, isokinetic muscle strength training, balance enhancement training, functional electrical stimulation, and electromyographic biofeedback therapy[21]. Early rehabilitation training, primarily based on the Bobath technique, involves guiding active movements of healthy limbs or assisting passive movements of affected limbs during the bed rest phase[22]. However, the traditional rehabilitation training has shown limited effectiveness for patients with severe hemiplegia.

Electromyographic biofeedback is a new therapeutic approach developed on the basis of the central nervous system plasticity theory. This method combines neuromuscular electrical stimulation with biofeedback, addressing the shortcomings of simple electrical stimulation[23]. It is the most active training method for restoring and improving muscle self-control, and it is one of the standard rehabilitation methods for foot drop in hemiplegic patients[24]. The present study compared the differences between traditional rehabilitation and electromyographic biofeedback therapy in treating limb motor dysfunction after stroke. The upper and lower limb motor function and wrist/ankle extension capabilities in both groups were evaluated before treatment, after 4 weeks, and after 8 weeks. The results showed no significant difference in the upper and lower limb motor function scores between the two groups before treatment. However, at 4 weeks and 8 weeks post-treatment, the electromyographic feedback treatment group demonstrated superior upper and lower limb motor function scores compared with the control group. The appearance and adequacy of wrist/ankle extension directly affect the motor function of patients’ hands and feet, prompting an investigation into the range of motion of the wrist and ankle joints. The results indicate that the electromyographic group exhibited a better wrist/ankle joint range of motion at 4 weeks and 8 weeks post-treatment than the control group. Svendsen et al[25] studied the effect of electromyographic biofeedback therapy on wrist dorsiflexion and radial wrist extension muscle contractions, confirming that electromyographic biofeedback considerably improves wrist joint mobility.

An important aspect of this study is the effect of electromyographic biofeedback therapy on patient emotions. The results show that the electromyographic biofeedback group had lower HADS scores than the control group after 4 and 8 weeks of treatment. The HAMD and HAMA scores were also lower in the electromyographic biofeedback group at both time points. By providing real-time feedback and promoting gradual improvements in motor control, electromyographic biofeedback therapy fosters a sense of achievement and reduces anxiety and depression. Patients who regain movement capabilities often experience increased confidence and reduced feelings of helplessness, which are critical factors in their overall recovery. Electromyographic biofeedback therapy not only improves motor function but also enhances emotional well-being by reducing tension and alleviating depressive symptoms[26]. Additionally, the structured nature of these therapy sessions offers psychological stability, reducing uncertainty and fostering a supportive environment through regular social interactions. These combined effects contribute to enhanced mental health outcomes, highlighting the holistic benefits of electromyographic biofeedback therapy beyond motor function improvement[27].

One limitation of this study is the relatively small sample size, which included 60 stroke survivors only. This limited sample size may affect the generalizability of the findings and suggests the need for further studies with larger cohorts to validate the effectiveness of electromyographic biofeedback therapy in a broader population. Future research should aim to expand the sample size and include diverse patient populations to better understand the therapeutic benefits and potential limitations across different subgroups. Additionally, longitudinal studies could provide more insights into the long-term effects of this intervention on motor function recovery and emotional well-being.

The application of electromyographic biofeedback therapy in the rehabilitation of physical dysfunction and reduction of post-stroke anxiety represents a novel approach with remarkable clinical implications. Unlike traditional rehabilitation methods, electromyographic biofeedback provides real-time feedback on muscle activity, enabling patients to actively participate in their recovery process. This active engagement not only fosters motor function improvement but also enhances emotional well-being by reducing anxiety and depression. Potential influencing factors include the severity of initial motor impairment, patient motivation, and adherence to the therapy regimen. This study highlights that structured biofeedback sessions can offer psychological stability and social support, which are crucial for holistic recovery. Clinically, this therapy has the potential to improve patient outcomes by addressing the physical and psychological aspects of stroke recovery. Future research should explore these influencing factors in greater detail and assess the long-term benefits of electromyographic biofeedback therapy in diverse patient populations, thereby validating its broader applicability and effectiveness.

CONCLUSION

Combining electromyographic biofeedback therapy with conventional rehabilitation treatment can effectively improve upper and lower limb motor function, balance function, post-stroke anxiety, ADL, and wrist/ankle extension function in stroke survivors, with superior efficacy compared with conventional rehabilitation treatment.