1,721,044 research outputs found
Comparison Between Manual and (Semi-)Automated Analyses of Esophageal Diaphragm Electromyography During Endurance Cycling in Patients With COPD
No full textBackground: Electrocardiogram (ECG) contamination is present in diaphragm electromyography (EMGdi) recordings. Obtaining EMGdi without ECG contamination is crucial for EMG amplitude analysis. Manually selecting EMGdi in between QRS complexes has been most commonly applied in recent years (manual method). We developed a semi-automated analysis method based on Least Mean Square Adaptive Filtering combined with a synchronously recorded separate ECG channel to remove ECG artifacts from the EMGdi signals. We hypothesized that this approach would shorten analysis duration and might minimize the potential for inter-rater disagreement. Aims: We aimed to evaluate agreement between the semi-automated method and the manual method and inter-rater reliability of the manual method. Methods: Electromyography signals of seven patients with COPD were recorded using an esophageal catheter during an exercise test on a cycle ergometer. Four patients subsequently participated in an inspiratory muscle training (IMT) program for 8 weeks. After IMT, the tests were repeated. EMGdi/EMGdiMax as obtained either manually by the two assessors or retrieved from the semi-automated method were compared. Results: Semi-automated EMGdi/EMGdiMax agreed well with values obtained by one of the two manual assessors (assessor 1) both at pre-intervention measurements (mean difference -0.5%, 95% CI: -19.6 to 18.6%) and for the pre/post IMT differences (mean difference 1.2%, 95% CI: -16.8 to 19.2%). Intra-class correlation coefficients between methods were 0.96 (95% CI: 0.94-0.97) at pre-intervention measurements and 0.78 (95% CI: 0.58-0.89) for pre/post IMT differences (both p < 0.001). EMGdi/EMGdiMax from assessor 2 was systematically lower than from assessor 1 and agreed less well with the semi-automated method both at pre-intervention measurements (mean difference: 9.3%, 95% CI: -11.4 to 29.9%) and for pre/post IMT differences (mean difference 7.0%, 95% CI: -20.4 to 34.4%). Analysis duration of the semi-automated method was significantly shorter (29 ± 9 min) than the manual method (82 ± 20 min, p < 0.001). Conclusion: The developed semi-automated method is more time efficient and will be less prone to inter-rater variability that was observed when applying the manual analysis method. It is, therefore, proposed as a new standard for objective EMGdi amplitude analyses in future studies.sponsorship: This research project was supported by the Research Foundation - Flanders (FWO): G0A4516N - ZKC9570 - C22/15/035. ZL is a recipient of an ERS fellowship (LTRF 2016-6686) and a postdoctoral research fellow of the FWO Flanders (12U5618N). AR is supported by the Coordination for the Improvement of Higher Education Personnel (CAPES), Brazil (88881.188754/2018-01). SD is supported by Chiang Mai University's scholarship, Chiang Mai, Thailand (Ref. No. 6392(7)/0807). (Research Foundation - Flanders (FWO)|G0A4516N - ZKC9570 - C22/15/035, ERS fellowship|LTRF 2016-6686, Coordination for the Improvement of Higher Education Personnel (CAPES), Brazil|88881.188754/2018-01, Chiang Mai University's scholarship, Chiang Mai, Thailand|6392(7)/0807)status: Publishe
Disturbed proprioceptive postural control may be related to impaired multifidus muscle quality in people with low back pain.
No full textBackground and Aim
Low back pain (LBP) is the leading cause of disability worldwide. Impaired proprioception during postural control might be a contributing factor to LBP, but it remains unknown if this relates to structural changes in spine-controlling muscles such as the lumbar multifidus.
Therefore, this study aimed (1) to investigate potential differences in lumbar proprioceptive use during standing as well as multifidus size and echo-intensity between people with and without LBP, and (2) to determine the association between proprioceptive use during standing l and multifidus size and echo-intensity.
Methods
In 36 participants with recurrent LBP (19 men, 17 women; Age= 44 ± 11 years; BMI= 25.3 ± 3.7) and 32 healthy controls (11 men, 21 women; Age= 38 ± 11 years ; BMI= 22.2 ± 2.4), proprioceptive use was evaluated by applying muscle vibration to ankle and back muscles during standing on stable and unstable ground. Center of pressure displacements in response to vibration were measured with a force plate (Kistler). Multifidus volume was measured from lumbar level L2 to L5, cross-sectional area and echo-intensity were measured at lumbar level L5 with three-dimensional freehand ultrasound (SonixTouch Q+ with Optitrack V120:Trio, NaturalPoint, USA). Between-group differences were assessed using non-parametric tests. Spearman correlations were calculated and Bonferroni corrections were applied for multiple comparisons (p= 0.013).
Results
Compared to healthy controls, people with LBP showed a more ankle-steered postural control (p= 0.019), decreased lumbar proprioceptive reliance on unstable ground (p= 0.04) and increased multifidus echo-intensity (p 0.60). After Bonferroni correction, only center of pressure displacement during back muscle vibration on stable ground showed a small negative correlation with multifidus echo-intensity (r= -0.38, p= 0.015).
Conclusions
This study confirmed that compared to healthy controls, people with LBP showed impaired ability to up-weight lumbar proprioceptive use during more challenging postural conditions. This decreased proprioceptive acuity could perhaps be related to impaired multifidus quality, but not to multifidus size. However, there was only a moderate correlation on stable ground, and a few trends for significance after Bonferroni correction, but no associations in more complex postural conditions. Future studies could use larger samples with more advanced measurement techniques to determine muscle quality, such as muscle biopsies, or texture analysis for echo-intensity. This further clarify the relation between muscle quality and proprioceptive postural control in people with LBP.FWO (grant 11B6522N, grant G072122N
Enhancing postural control, pain and disability through proprioceptive training in individuals with low back pain: a proof-of-concept.
No full textLow back pain (LBP) is a leading cause of global disability. Individuals with LBP often exhibit impaired proprioceptive postural control, which may contribute to the persistence of their condition. The effectiveness of targeted proprioceptive training in addressing these deficits and alleviating pain and disability remains unclear. This study aimed to evaluate the impact of proprioceptive training on (1) proprioceptive postural control and (2) associated pain and disability in individuals with LBP.
Twenty-five individuals with recurrent LBP (14 men, 11 women; mean age 47 ± 10 years; BMI 24.1 ± 2.3) participated in an 8-week proprioceptive training program focusing on sensing, differentiating, and localizing lumbar postures, movements, and muscle activation. Participants integrated these exercises into their daily routines.
Postural control assessments were performed on stable and unstable surfaces with visual input occluded. Muscle vibration stimulated ankle and back muscle spindles to induce center of pressure (COP) displacements, measured using a force plate. A ratio of COP displacement in response to ankle versus back muscle vibration was calculated. Clinical outcomes were assessed with the Modified Low Back Pain Disability Questionnaire (MDQ) and self-reported percentage improvements in pain and disability (0–100%). Non-parametric statistical methods were used.
Proprioceptive training led to increased COP displacement in response to back muscle vibration on stable (p = 0.036) and unstable surfaces (p = 0.043). The ratio of ankle-to-back muscle vibration indicated greater reliance on lumbar proprioception under unstable conditions (p = 0.034). Clinically, MDQ scores improved significantly (pre-training: 27 ± 10; post-training: 14 ± 10, p < 0.001), alongside substantial reductions in disability (51%) and pain (49%).
Proprioceptive training improved lumbar proprioception and postural control, likely through enhanced muscle spindle sensitivity and segmental control. Participants shifted from rigid ankle strategies to adaptive lumbar proprioceptive reliance, improving adaptability to unstable conditions. These benefits were accompanied by significant reductions in pain and disability, underscoring the clinical value of proprioceptive training for individuals with LBP.Research Foundation Flanders - FWO (grant 11B6522N, grant G072122N
Enhancing postural control, pain and disability through proprioceptive training in individuals with low back pain: a proof-of-concept.
No full textLow back pain (LBP) is a leading cause of global disability. Individuals with LBP often exhibit impaired proprioceptive postural control, which may contribute to the persistence of their condition. The effectiveness of targeted proprioceptive training in addressing these deficits and alleviating pain and disability remains unclear. This study aimed to evaluate the impact of proprioceptive training on (1) proprioceptive postural control and (2) associated pain and disability in individuals with LBP.
Twenty-five individuals with recurrent LBP (14 men, 11 women; mean age 47 ± 10 years; BMI 24.1 ± 2.3) participated in an 8-week proprioceptive training program focusing on sensing, differentiating, and localizing lumbar postures, movements, and muscle activation. Participants integrated these exercises into their daily routines.
Postural control assessments were performed on stable and unstable surfaces with visual input occluded. Muscle vibration stimulated ankle and back muscle spindles to induce center of pressure (COP) displacements, measured using a force plate. A ratio of COP displacement in response to ankle versus back muscle vibration was calculated. Clinical outcomes were assessed with the Modified Low Back Pain Disability Questionnaire (MDQ) and self-reported percentage improvements in pain and disability (0–100%). Non-parametric statistical methods were used.
Proprioceptive training led to increased COP displacement in response to back muscle vibration on stable (p = 0.036) and unstable surfaces (p = 0.043). The ratio of ankle-to-back muscle vibration indicated greater reliance on lumbar proprioception under unstable conditions (p = 0.034). Clinically, MDQ scores improved significantly (pre-training: 27 ± 10; post-training: 14 ± 10, p < 0.001), alongside substantial reductions in disability (51%) and pain (49%).
Proprioceptive training improved lumbar proprioception and postural control, likely through enhanced muscle spindle sensitivity and segmental control. Participants shifted from rigid ankle strategies to adaptive lumbar proprioceptive reliance, improving adaptability to unstable conditions. These benefits were accompanied by significant reductions in pain and disability, underscoring the clinical value of proprioceptive training for individuals with LBP.Research Foundation Flanders - FWO (grant 11B6522N, grant G072122N
Inspiratory muscle training decreases ankle proprioceptive use during balance control in patients with COPD.
No full textInspiratory muscle training decreases ankle proprioceptive use during balance control in patients with COPD.
No full textBack-to-Back, a proof of concept study investigating the role of back muscle characteristics to tailor exercise therapy for recurrent non-specific low back pain: study protocol and preliminary analysis of proprioceptive postural control results
No full textBackground and aim
Non-specific low back pain (NSLBP) is the main cause of disability worldwide and current treatments have limited effects. Alterations in macroscopic, microscopic, electrophysiological and hemodynamic lumbar muscle characteristics and proprioceptive postural control (PPC) are found in people with NSLBP and directing treatment based on shared underlying mechanisms (phenotypes), could improve its effects. Therefore, this study aims to determine the most discriminating lumbar muscle characteristics between patients with NSLBP and healthy controls, investigate their interrelatedness and relationship with PPC and delineate NSLBP phenotypes based on them. Additionally, to investigate whether proprioceptive exercises have a greater effect on specific NSLBP phenotypes.
Methods
Lumbar multifidus and erector spinae muscle characteristics will be evaluated and compared in 53 people with recurrent NSLBP and 47 healthy controls. For PPC, the COP displacements in response to vibration to the ankle and back muscles are measured on a force plate, while standing on stable and unstable surface with vision occluded. Proprioceptive dominance is evaluated by the Relative Proprioceptive Weighting (RPW) ratio, with lower RPW values indicating more lumbar proprioceptive reliance. Muscle volume is investigated with 3D freehand ultrasound, and muscle activation and oxygenation with electromyography and near-infrared spectroscopy, respectively. The 53 people with NSLBP also receive a 16-week intervention focusing on improving their ability to sense and discriminate low back position, muscle activation and lumbar movement. These proprioceptive exercises are integrated into the patients’ daily lives and comprise a high-load lifting exercise. Their effects are evaluated at 8 weeks, 16 weeks and 16 weeks after the end of the intervention.
Results
Recruitment is ongoing, currently five people with recurrent NSLBP are enrolled and analysed descriptively. Preliminary results on PPC include increased lumbar proprioceptive reliance after eight (Pre: 0.69 ± 0.04; Post: 0.46 ± 0.30 stable and Pre: 0.58 ± 0.13; Post: 0.44 ± 0.31 unstable) and 16 weeks (Post: 0.40 ± 0.30 stable and Post: 0.34 ± 0.16 unstable) and increased COP displacement in response to lumbar vibration on stable (Pre: 0.018 ± 0.011; Post: 0.020 ±0.012) and unstable (Pre: 0.015 ± 0.013; Post: 0.021 ± 0.009) after 16 weeks of intervention.
Conclusion
Preliminary results show increased lumbar proprioceptive use and a switch in dominant reliance from ankle to lumbar proprioception in response to this proprioceptive intervention, translating to improved PPC. Further effects on the different lumbar muscle characteristics and their correlation with PPC will be investigated. Phenotypes of people with NSLBP will be delineated and the effects of this intervention on them will be examined. Results may improve patient-tailored exercise therapy for people with NSLBP.Research Foundation Flanders (FWO) - grant numbers 11B6522N and G072122
The forgotten role of back muscle characteristics to tailor exercise therapy for recurrent non-specific low back pain: Study protocol for the Back-to-Back study
No full textBackground and aims: Current treatments for non-specific low back pain (NSLBP) have only limited effects. Identifying phenotypes of patients that share underlying mechanisms towards which clinicians could direct treatment could improve the effects. Previous studies found macroscopic, microscopic, electrophysiological, and proprioceptive changes in the back muscles of patients with NSLBP. However, no studies delineated NSLBP phenotypes based on back muscle characteristics.
Methods: We will evaluate various characteristics of the lumbar multifidus and erector spinae in 90 patients with NSLBP and 55 healthy controls: muscle volume with 3D freehand ultrasound, muscle fiber type composition with minimally-invasive muscle biopsies, proprioceptive use during postural control by applying muscle vibration during standing on a force plate, and muscle activation and oxygenation with electromyography and near-infrared spectroscopy (Fig. 1). We will determine the most discriminating muscle characteristics between patients with NSLBP and controls, based upon which phenotypes will be delineated. Then, the patients with NSLBP will be randomized into two groups receiving a 16-week program of proprioceptive training or resistance training. The effect of both programs on back muscle characteristics and disability will be evaluated halfway the program, at the end of the program, and 16 weeks after the end of training.
Results: The protocol is submitted to the Ethical Committees of UZ/KU Leuven and UHasselt. The study is funded by the Research Foundation - Flanders (FWO) (G072122N). Participant recruitment and data collection are anticipated to start in March 2023.
Conclusions: We expect the results to help improve the patient-tailored exercise therapy for NSLBP
The forgotten role of back muscle characteristics to tailor exercise therapy for recurrent non-specific low back pain: Study protocol for the Back-to-Back study
No full textBackground and aims: Current treatments for non-specific low back pain (NSLBP) have only limited effects. Identifying phenotypes of patients that share underlying mechanisms towards which clinicians could direct treatment could improve the effects. Previous studies found macroscopic, microscopic, electrophysiological, and proprioceptive changes in the back muscles of patients with NSLBP. However, no studies delineated NSLBP phenotypes based on back muscle characteristics.
Methods: We will evaluate various characteristics of the lumbar multifidus and erector spinae in 90 patients with NSLBP and 55 healthy controls: muscle volume with 3D freehand ultrasound, muscle fiber type composition with minimally-invasive muscle biopsies, proprioceptive use during postural control by applying muscle vibration during standing on a force plate, and muscle activation and oxygenation with electromyography and near-infrared spectroscopy (Fig. 1). We will determine the most discriminating muscle characteristics between patients with NSLBP and controls, based upon which phenotypes will be delineated. Then, the patients with NSLBP will be randomized into two groups receiving a 16-week program of proprioceptive training or resistance training. The effect of both programs on back muscle characteristics and disability will be evaluated halfway the program, at the end of the program, and 16 weeks after the end of training.
Results: The protocol is submitted to the Ethical Committees of UZ/KU Leuven and UHasselt. The study is funded by the Research Foundation - Flanders (FWO) (G072122N). Participant recruitment and data collection are anticipated to start in March 2023.
Conclusions: We expect the results to help improve the patient-tailored exercise therapy for NSLBP
Back-to-Back, a proof of concept study investigating the role of back muscle characteristics to tailor exercise therapy for recurrent non-specific low back pain: study protocol and preliminary analysis of proprioceptive postural control results
No full textBackground and aim
Non-specific low back pain (NSLBP) is the main cause of disability worldwide and current treatments have limited effects. Alterations in macroscopic, microscopic, electrophysiological and hemodynamic lumbar muscle characteristics and proprioceptive postural control (PPC) are found in people with NSLBP and directing treatment based on shared underlying mechanisms (phenotypes), could improve its effects. Therefore, this study aims to determine the most discriminating lumbar muscle characteristics between patients with NSLBP and healthy controls, investigate their interrelatedness and relationship with PPC and delineate NSLBP phenotypes based on them. Additionally, to investigate whether proprioceptive exercises have a greater effect on specific NSLBP phenotypes.
Methods
Lumbar multifidus and erector spinae muscle characteristics will be evaluated and compared in 53 people with recurrent NSLBP and 47 healthy controls. For PPC, the COP displacements in response to vibration to the ankle and back muscles are measured on a force plate, while standing on stable and unstable surface with vision occluded. Proprioceptive dominance is evaluated by the Relative Proprioceptive Weighting (RPW) ratio, with lower RPW values indicating more lumbar proprioceptive reliance. Muscle volume is investigated with 3D freehand ultrasound, and muscle activation and oxygenation with electromyography and near-infrared spectroscopy, respectively. The 53 people with NSLBP also receive a 16-week intervention focusing on improving their ability to sense and discriminate low back position, muscle activation and lumbar movement. These proprioceptive exercises are integrated into the patients’ daily lives and comprise a high-load lifting exercise. Their effects are evaluated at 8 weeks, 16 weeks and 16 weeks after the end of the intervention.
Results
Recruitment is ongoing, currently five people with recurrent NSLBP are enrolled and analysed descriptively. Preliminary results on PPC include increased lumbar proprioceptive reliance after eight (Pre: 0.69 ± 0.04; Post: 0.46 ± 0.30 stable and Pre: 0.58 ± 0.13; Post: 0.44 ± 0.31 unstable) and 16 weeks (Post: 0.40 ± 0.30 stable and Post: 0.34 ± 0.16 unstable) and increased COP displacement in response to lumbar vibration on stable (Pre: 0.018 ± 0.011; Post: 0.020 ±0.012) and unstable (Pre: 0.015 ± 0.013; Post: 0.021 ± 0.009) after 16 weeks of intervention.
Conclusion
Preliminary results show increased lumbar proprioceptive use and a switch in dominant reliance from ankle to lumbar proprioception in response to this proprioceptive intervention, translating to improved PPC. Further effects on the different lumbar muscle characteristics and their correlation with PPC will be investigated. Phenotypes of people with NSLBP will be delineated and the effects of this intervention on them will be examined. Results may improve patient-tailored exercise therapy for people with NSLBP.Research Foundation Flanders (FWO) - grant numbers 11B6522N and G072122
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