Search Results (28)

Arthrogenic muscle inhibition (AMI), neurophysiological suppression of voluntary quadriceps activation triggered by joint effusion and inflammation, is consistently initiated within hours of any form of knee surgery. If not actively counteracted during the first two postoperative weeks, AMI may drive a cascade of neuromuscular, morphological, and biomechanical deficits that can persist for years, substantially increasing the risk of post-traumatic osteoarthritis, reinjury, and long-term functional disability. Emerging evidence indicates that preoperative patient-related factors, including baseline quadriceps strength, age, body mass index, and physical fitness, further modulate the rehabilitation response and should be considered in planning early postoperative protocols. This narrative review, which was not designed as a systematic review or meta-analysis and therefore does not include formal quality assessment or pooled statistical analysis, evaluates evidence for seven early-phase (0–2 weeks postoperative) knee muscle activation interventions: neuromuscular electrical stimulation (NMES), isometric quadriceps exercise, blood flow restriction (BFR) training, electromyographic (EMG) biofeedback, open and closed kinetic chain (OKC/CKC) exercise, cryotherapy, and continuous passive motion (CPM). Findings are synthesized against six clinically relevant dimensions, safety in the 0–2 week window, home-based usability, capacity to overcome AMI, requirement for volitional effort, objective monitoring capability, and progressive resistance, to characterize a consistent pattern: no single existing modality simultaneously meets all combined requirements for home deployment, volitional engagement, objective monitoring, and progressive resistance from postoperative day one. This collective unmet need provides direction for future device development and clinical research. Full article

Background/Objectives: Wearable technology is increasingly used to provide biofeedback in physical rehabilitation; however, there is no consensus on which biofeedback parameter is most appropriate for clinical use, as most studies evaluate only one arbitrarily selected parameter. This study presents a wearable multimodal biofeedback system integrating multiple parameters selected based on the prior literature and evaluates its feasibility, usability, and implementation within a rehabilitation context through a longitudinal post-stroke case study. Methods: The system integrates inertial and electromyographic sensors to monitor centre of mass (CoM-B), joint angle (ANG-B), and muscle activity (EMG-B), delivering real-time sensory cues based on the monitored parameters. Feasibility was assessed in a post-stroke participant (male, 32 years, 29 months post-stroke, left hemiparesis, Fugl-Meyer Lower Extremity Score = 27) across 15 sessions involving stand-to-sit, split-stance weight shifting, and walking tasks. Each task was practiced with all three biofeedback parameters, with five sessions per parameter. Results: The motor performance varied across biofeedback parameters and tasks. CoM-B was associated with favourable trends in motor performance during stand-to-sit, showing improvements in medio-lateral displacement (0.03/session); ANG-B during walking, showing increased ankle dorsiflexion (1 deg/session); and EMG-B during split-stance weight shifting, showing increased tibialis anterior activation (5 µV/session). Conclusions: The findings generate the hypothesis that the ability of biofeedback to elicit favourable motor performance is task-dependent, suggesting that the choice of biofeedback parameters may need to be adapted to task demands. The system demonstrated high usability and feasibility, supporting its potential for post-stroke rehabilitation. Further studies are needed to test the generated hypothesis and evaluate the system efficacy. Full article

Laryngeal adductor breathing dystonia (LABD) is a rare form of focal, task-specific respiratory dystonia affecting the laryngeal muscles of unknown aetiology. Unlike classical laryngeal dystonia (spasmodic dysphonia), LABD is not primarily characterised by impaired speech, but rather by dysfunction of respiratory laryngeal control. The hallmark pathophysiological alteration consists of involuntary, action-induced adductor spasms of the laryngeal muscles during respiration, particularly during inspiration. LABD must be distinguished from inducible laryngeal obstruction (ILO), a broader, heterogeneous condition encompassing episodic, stimulus-triggered supraglottic or glottic closure, associated with asthma, reflux, or psychological triggers, that is generally not task-specific and lacks the neurological substrate characteristic of dystonia. In contrast, LABD is a persistent, effort-dependent, neurologically driven dystonia, demonstrable by paradoxical adductor spasms on fibreoptic laryngoscopy during normal inspiration and confirmed electromyographically by paradoxical thyroarytenoid muscle activation instead of the expected inspiratory relaxation. Traditional treatments, including respiratory retraining, speech therapy, biofeedback, psychotherapy, benzodiazepines, dopamine-blocking agents, and anticholinergic drugs, have proved largely ineffective. Tracheostomy may be required in cases of severe respiratory compromise. Botulinum toxin type A (BoNT/A) injections have been reported to successfully reduce inspiratory stridor in selected patients. Here, we present three cases of LABD displaying distinct phenotypes, in which typical features were associated with involvement of extra-laryngeal cranial districts, further expanding the known phenotypic spectrum of this condition. Full article

Background: Handball involves unilateral, high-demand actions that increase injury risk. The Windlass mechanism (WM) is a position-dependent plantar fascia tensioning system, activated by dorsiflexion of the first metatarsophalangeal joint, which increases medial longitudinal arch stiffness and contributes to foot stability. WM activation can be mechanically simulated using hallux wedges to induce controlled dorsiflexion, allowing graded engagement of the mechanism under standardized conditions. The primary aim of this study was to investigate how different wedge inclinations, with and without visual biofeedback, affect foot muscle activity during squats in elite female handball players. Methods: Seventeen elite female handball players performed squats at 65% of one-repetition maximum under six conditions combining three wedge inclinations (0°, 10°, 30°) with the presence or absence of visual biofeedback. Electromyographic activity (RMS and %MVC) of intrinsic and extrinsic foot muscles was recorded. Results: A significant increase in left abductor hallucis activation with the 10° wedge without biofeedback. Visual biofeedback significantly increased RMS and %MVC in intrinsic foot muscles and increased RMS in the left gastrocnemius (p < 0.05). No significant interaction was observed between wedge inclination and biofeedback. Conclusions: Controlled activation of the WM via hallux wedges and the use of visual biofeedback modulate foot muscle activity during squats. These strategies may be considered in training programs aimed at improving foot stability and reducing injury risk in elite female handball players. Full article

Background/Objectives: Urinary incontinence (UI) is a prevalent health condition with a negative impact on quality of life (QoL). Exercise therapy (ET), specifically, pelvic floor muscle training (PFMT), is recommended as a first-line conservative treatment for UI during pregnancy, childbirth, and the postpartum period. This study evaluated the effects of ET on the management of postpartum UI. Methods: A systematic search was conducted to identify clinical trials and randomized controlled trials including women over 18 years with postpartum UI. All included studies used ET as the main intervention. Studies were excluded if UI symptoms were attributable to factors outside the urinary tract or if participants had concomitant pathologies. Results: From 298 records screened, four trials were included. Three trials reported statistically significant improvements in UI outcomes, while findings for pelvic floor function and QoL showed greater heterogeneity. One trial found that supervised PFMT was associated with greater improvements in urinary symptoms (BFLUTS), vaginal pressure (18.96 mmHg (SD: 9.08)), and endurance (11.32 s (SD: 3.17)) compared to unsupervised training. Another trial using electromyographic biofeedback with electrical stimulation reported a continence rate exceeding 70% on the 20 min pad test, with improvements in perceived burden (VAS), symptoms (UDI), and QoL (IIQ). A third trial combining PFMT with infrared physiotherapy showed improvements in pelvic floor function (PFIQ-7, PFDI-20), urodynamic parameters, urine loss, and QoL (GQOLI-74). In the remaining trial, within-group improvements were observed, with no statistically significant between-group differences. Conclusions: ET appears to be beneficial for postpartum UI, with a moderate certainty of evidence. While the greatest benefits are observed with supervised PFMT, the diversity of comparators, and the risk of performance bias limit definitive conclusions regarding its superiority. Given the short-term follow-up, it remains unclear whether the results are influenced by the spontaneous recovery trajectory in the postpartum period and if these effects are sustained in the long term. Full article

Background: Current clinical practice still lacks consistent evidence in the physiotherapy management of rotator cuff-related pain syndrome (RCS). The purpose of this trial was to compare the effectiveness of a scapular-focused treatment with and without real-time electromyographic biofeedback (EMGBF) to a control therapy in patients with RCS, in the short-term. Methods: 60 patients with RCS were divided into three groups: the scapular-focused exercise protocol group (P_G n = 20), the scapular-focused exercise protocol with EMGBF group (P+EMGBF_G n = 20), and the control therapy group (CT_G n = 20). Values of pain and function [Shoulder Pain and Disability Index (SPADI) questionnaire, complemented by the Numeric Pain Rating Scale (NPRS) and Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire], scapular stabilizer neuromuscular control (SSNC), scapular stabilizer activation onset (SSAO), dynamic scapular alignment, range of motion (ROM), and glenohumeral flexor and abductor muscle strength (GMS) were assessed at baseline and after 6 weeks and compared within and between groups. Results: There were significant differences in pain and function, SSNC, SSAO, dynamic scapular alignment, ROM, and GMS in all groups between the initial and 6-week assessments. However, the P+EMGBF_G showed superior results in pain and function, SSNC, and dynamic scapular alignment than the CT_G and superior results in SSNC than the P_G. The P_G had superior results in pain and function and dynamic scapular alignment than the CT_G. Conclusions: This trial supports the use of a scapular-focused exercise protocol as a comparative approach that effectively improves pain and function in patients with rotator cuff-related shoulder pain syndrome. These results in pain and function were shown to be independent of the use of EMGBF. Full article

(1) Background: Biofeedback and neurofeedback are gaining attention as non-invasive rehabilitation strategies in Parkinson’s disease (PD) treatment, aiming to modulate motor and non-motor symptoms through the self-regulation of physiological signals. (2) Objective: This review explores the application of biofeedback techniques, electromyographic (EMG) biofeedback, heart rate variability (HRV) biofeedback, and electroencephalographic (EEG) neurofeedback in PD rehabilitation, analyzing their impacts on motor control, autonomic function, and cognitive performance. (3) Methods: This review critically examined 15 studies investigating the efficacy of electromyographic (EMG), heart rate variability (HRV), and electroencephalographic (EEG) feedback interventions in PD. Studies were selected through a systematic search of peer-reviewed literature and analyzed in terms of design, sample characteristics, feedback modality, outcomes, and clinical feasibility. (4) Results: EMG biofeedback demonstrated improvements in muscle activation, gait, postural stability, and dysphagia management. HRV biofeedback showed positive effects on autonomic regulation, emotional control, and cardiovascular stability. EEG neurofeedback targeted abnormal cortical oscillations, such as beta-band overactivity and reduced frontal theta, and was associated with improvements in motor initiation, executive functioning, and cognitive flexibility. However, the reviewed studies were heterogeneous in design and outcome measures, limiting generalizability. Subgroup trends suggested modality-specific benefits across motor, autonomic, and cognitive domains. (5) Conclusions: While EMG and HRV systems are more accessible for clinical or home-based use, EEG neurofeedback remains technically demanding. Standardization of protocols and further randomized controlled trials are needed. Future directions include AI-driven personalization, wearable technologies, and multimodal integration to enhance accessibility and long-term adherence. Biofeedback presents a promising adjunct to conventional PD therapies, supporting personalized, patient-centered rehabilitation models. Full article

The number of people suffering from urinary incontinence increases every year. Along this trend, the knowledge of society increases regarding the various methods available for treating this ailment. Both patients and researchers are constantly looking for new treatments for urinary incontinence. One of the new solutions is sonofeedback of the pelvic floor muscles, which may help to strengthen them and thus reduce the problem. The aim of this study was to evaluate the effectiveness of sonofeedback and transvaginal electrostimulation in increasing the bioelectrical activity of pelvic floor muscles in postmenopausal women with stress urinary incontinence. Sixty women with stress urinary incontinence were enrolled in the study. The patients were divided into two groups: A, where sonofeedback was used, and B, where electrostimulation of the pelvic floor muscles was performed with biofeedback training. In patients, the resting bioelectrical activity of the pelvic floor muscles was assessed using an electromyograph. The assessment of the resting bioelectrical activity of the pelvic floor muscles was performed before the therapy, after the 5th training, and after the therapy. It was observed that after the end of the therapy, the average bioelectrical potential increased by 1.1 µV compared with the baseline in group A. It can be suggested that the sonofeedback method is comparatively effective in reducing symptoms that are associated with urinary incontinence as an electrostimulation method with biofeedback training. Full article

Facial palsy (FP) significantly impacts patients’ quality of life. The accurate classification of FP severity is crucial for personalized treatment planning. Additionally, electromyographic (EMG)-based biofeedback shows promising results in improving recovery outcomes. This prospective study aims to identify EMG time series features that can both classify FP and facilitate biofeedback. Therefore, it investigated surface EMG in FP patients and healthy controls during three different facial movements. Repeated-measures ANOVAs (rmANOVA) were conducted to examine the effects of MOTION (move/rest), SIDE (healthy/lesioned) and the House–Brackmann score (HB), across 20 distinct EMG parameters. Correlation analysis was performed between HB and the asymmetry index of EMG parameters, complemented by Fisher score calculations to assess feature relevance in distinguishing between HB levels. Overall, 55 subjects (51.2 ± 14.73 years, 35 female) were included in the study. RmANOVAs revealed a highly significant effect of MOTION across almost all movement types (p < 0.001). Integrating the findings from rmANOVA, the correlation analysis and Fisher score analysis, at least 5/20 EMG parameters were determined to be robust indicators for assessing the degree of paresis and guiding biofeedback. This study demonstrates that EMG can reliably determine severity and guide effective biofeedback in FP, and in severe cases. Our findings support the integration of EMG into personalized rehabilitation strategies. However, further studies are mandatory to improve recovery outcomes. Full article

Background and Objectives: The aim of this study was to compare the effects of pelvic floor muscle contraction training (PFMCT) using verbal education, digital vaginal palpation (DVP), or perineometer on the common errors made during pelvic floor muscle contraction (PFMC) in women. Materials and Methods: A total of 48 women participated, and they were randomly assigned to three groups (Group I: PFMCT with verbal education, n = 16; Group II: PFMCT with DVP, n = 16; and Group III: PFMCT with perineometer, n = 16). Participants who had not previously received PFMCT were evaluated for pelvic floor muscle strength using the Modified Oxford Scale (MOS), and pelvic floor muscle activation was assessed with electromyographic biofeedback (EMG-BF). Possible errors during pelvic floor muscle contraction (gluteal, adductor and/or abdominal muscle contractions, stop breathing (breath holding), enhanced inhaling, and straining) were evaluated through inspection, palpation, or EMG-BF. After pre-training evaluations, all participants received training on pelvic floor. After this general training, each group received PFMCT using the specific training method for their group. After the training, the same evaluations were repeated. The sessions were conducted one-on-one and lasted for an average of one hour. Results: After the training, MOS values increased in Group II and Group III, while EMG-BF values only increased in Group II (p < 0.05). The number of incorrect movements during PFMC decreased after the training in all three groups (p < 0.05). The abdominal muscle contraction value monitored by EMG-BF only decreased in Group II (p < 0.05). Conclusions: Our study demonstrated that the PFMCT applied using the DVP method was more effective in creating more accurate and stronger muscle contractions and reducing common errors when compared to pre- and post-training values. Significant differences were observed between the groups in terms of performance improvements, with Group II showing the most notable progress. These results support the potential for DVP to yield better outcomes when used in PFMT. Full article

The use of electromyographic biofeedback (EMG-BF) in the rehabilitation of injuries has been widely referenced in the psychological literature. However, despite some pioneering work in the field of sports, its use in the rehabilitation of sports injuries has hardly been explored. A case of two professional soccer players who each suffered a distal radius fracture is presented here. Parallel to the rehabilitation plan established by medical services, an intervention strategy using EMG-BF was established. An EMG-BF intervention was performed on the brachioradialis muscle with the aim of improving the voluntary control of its electromyographic activity. The study protocol was registered with the identifier NCT05376072. An ABA design was used. In each session, a pre- and postline was recorded to determine the EMG gain acquired at each point of the session. After six sessions, the intervention was terminated. One more follow-up session was performed. The results obtained indicated the efficacy of the intervention; a statistically significant increase in muscle activity in the brachioradialis muscle was observed. Full article

The goal of the trial was to examine the effects of adding electromyographic biofeedback (EMG-BF) to the conventional program of physiotherapy after total hip arthroplasty (THA) on functional recovery and quality of life. The trial was designed as a prospective, interventional, single-blinded randomized controlled study. Ninety patients were randomized into an experimental group (EG) (n = 45; mean age 63.9 ± 8.8) and control group (CG) (n = 45; mean age 63.9 ± 9). All patients received 21 days of physiotherapy which consisted of therapeutic exercise (land-based and aquatic), electrotherapy, and education. Electromyographic biofeedback was added to a portion of the land-based exercise in EG. The Hip Disability and Osteoarthritis Outcome Score (HOOS), Numeric Rating Scale (NRS), Short Form Health Survey-36 (SF-36), use of a walking aid, 30 s chair stand test (CST) as well as the Timed Up and Go (TUG) test were used for outcome measurement. A higher proportion of the participants in both groups did not need a walking aid after the intervention (p < 0.05). All participants improved their 30 s CST and TUG results (p < 0.001), as well as their NRS and HOOS scores (p < 0.05). No significant differences between the groups were found. There were no additional benefits from adding EMG-BF to the conventional physiotherapy protocol. Full article

Electromyographic biofeedback (EMG-BF) is a technique that can contribute to the improvement of muscle tone and control in the rehabilitation process after injury. The aim of this research was to determine the effectiveness of EMG-BF in increasing the electromyographic activity of the vastus lateralis after knee injury. The sample consisted of four individuals who had undergone surgery or rehabilitation to resolve either a partial meniscal tear or a patellar tendon strain. The intervention consisted of a program of ten sessions of EMG-BF work. Twelve trials were performed in each session, in which participants were instructed to target the muscle tension produced by the vastus lateralis of the uninjured hemilateral limb. Of the twelve trials in each session, the first three and the last three were performed without feedback, and the intermediate six with feedback. The recording of muscle activity was performed using CY-351/2 Mioback equipment, which allowed the amplitude of the electromyographic signal to be evaluated. The results indicated that the sample analyzed reached greater amplitude during the biofeedback trials, both for the maximum (Z = −13.43, p < 0.001, Cohen’s d = 0.64, 95% CI (0.27, 1.01)) and mean (Z = −7.26, p < 0.001, Cohen’s d = 0.24, 95% CI (−0.12, 0.60)) values. The amplitude also increased throughout the ten sessions, both for the maximum (Z = −3.06, p < 0.01, Cohen’s d = 1.37, 95% CI (0.29, 2.45)) and mean (Z = −3.06, p < 0.01, Cohen’s d = 1.20, 95% CI (0.34, 2.08)) values. Thus, the results highlight the efficacy of this technique in improving muscle activity, suggesting that it is a useful therapeutic procedure in injury recovery. Full article

Excessive masticatory muscle activity is generally present in awake bruxism, which is related to increased anxiety and stress. It has been hypothesized that biofeedback could potentially manage awake bruxism, however, its effectiveness has not been empirically analyzed in a systematic manner. Therefore, this systematic review was designed to determine the effectiveness of biofeedback compared to other therapies in adults with awake bruxism. Extensive searches in five databases looking for randomized controlled trials (RCTs) that included biofeedback to manage awake bruxism were targeted. The risk of bias (RoB) assessment was conducted using the Cochrane RoB-2 tool. Overall, four studies were included in this systematic review, all of which used the electromyographic activity of the masticatory muscles during the day and night as the main endpoint. Auditory and visual biofeedback could reduce the excessive level of masticatory muscle activity in a few days of intervention. The majority of the included studies had a high RoB and only one study had a low RoB. The standardization of the biofeedback protocols was also inconsistent, which makes it difficult to establish the ideal protocol for the use of biofeedback in awake bruxism. Thus, it is proposed that future studies seek to reduce methodological risks and obtain more robust samples. Full article

Pelvic floor musculature assessment methods are generally invasive, subjective, and technologically expensive. Therefore, there is a need to identify other methods that can predict changes in the function of these muscles. This study aimed to verify whether the levels of strength and myoelectric activity of pelvic floor muscles (PFM) can be related to handgrip strength (HGS), to ensure faster and earlier identification of possible dysfunctions of this musculature. Furthermore, we verified whether these variables vary across different age groups. This was a cross-sectional observational study involving 44 healthy women. The women were divided into two groups: the young (18–35 years) and middle-aged (36–55 years) adult groups. Social, anthropometric, and clinical data were collected from the participants, and a functional assessment of their PFM was performed by bidigital palpation, electromyographic biofeedback (sEMG), and HGS (using a dynamometer). The levels of physical and sexual activity were measured using the International Physical Activity Questionnaire (IPAQ) and Sexual Quotient–Female version (SQ-F) questionnaire. There were no differences in HGS, power/pressure, sEMG, SQ-F score, or IPAQ score between the two groups (p > 0.05). Moderate correlation (r = 0.601; p = 0.019) was observed during multivariate analysis. HGS is related to mean amplitudes (p = 0.123), MVC (p = 0.043), sexual function (p = 0.049), and physical activity (p = 0.004). We therefore conclude that there were no differences between HGS and PFM strength in young adult and middle-aged women. Furthermore, HGS is related to the PFM functionality, sexual function, and physical activity. Full article