TauG-guidance of dynamic balance control during gait initiation in patients with chronic fatigue syndrome and fibromyalgia

Test-Retest Reliability and Concurrent Validity of the 3 m Backward Walk Test under Single and Dual-Task Conditions in Women with Fibromyalgia

BACKGROUND

Previous studies have reported good test-retest reliability for the 3 m backward test (3MBWT) in different populations. However, reliability of the 3MBWT has not been studied in fibromyalgia (FM) under single and dual-task conditions; Methods: A total of 21 women with FM participated in this study. Participants completed the Revised Fibromyalgia Impact Questionnaire and two physical fitness tests: the 3MBWT and the Timed Up and Go (TUG). The dual-task condition consisted of subtracting two by two while performing the test, starting from a random number less than 100; Results: Values showed that the 3MBWT can be considered reliable under single and dual-task conditions when measured with both a manual stopwatch and a Chronopic automatic stopwatch. A strong concurrent validity was shown of 3MBWT and TUG results in the test and retest and the different devices. The relationship between the performance of the 3MBWT in test and retest conditions under single and dual-task conditions measured with different devices and the impact of the disease were high; Conclusions: The 3MBWT is a reliable tool under the single and dual-task conditions in women with FM. It shows higher reliability values when time is taken using a Chronopic. This test also shows high concurrent validity with the TUG test. Its performance is related to the impact of the disease.

[Bibliometric analysis of the thematic evolution in fibromyalgia and biomechanics (1985-2021)]

The main objective of the study is to analyse the scientific evolution of the research field of fibromyalgia and biomechanics. A search was carried out in Web of Science, from 1985 to 2021. With those results, a bibliometric map of keywords was created with VOSviewer. On top of that, scientific mapping and performance analysis were also conducted using SciMAT. A total of 233 articles from around the world were analysed, highlighting the production of the USA and Spain. The results show great diversity in topics with 54 different topics and 33 keywords. Although most of the topics found are not widely developed except the topics of physical activity and symptomatology. In conclusion, the study of fibromyalgia and biomechanics has generally grown over time.

Individuals with fibromyalgia have a different gait pattern and a reduced walk functional capacity: a systematic review with meta-analysis

Background

The aim of the present study was to perform a systematic review and meta-analysis comparing walking test performance and gait pattern between individuals with and without fibromyalgia (FM).

Methodology

This systematic review was registered in PROSPERO with the following reference: CRD42018116200.The search for the scientific articles in this systematic review was carried out using the MEDLINE, SCOPUS, PEDRO, CINHAL and WEB OF SCIENCE databases. A combination of three conceptual groups of terms was used: (1) fibromyalgia; (2) walk (performance) tests; and (3) gait analysis. The included articles were analyzed for both functional and pattern of walking data of patients with FM. In order to provide a better estimate of the difference between individuals with and without FM on gait, a meta-analysis was performed on the 6MWT (6-minute walk test).

Results

Thirty-six studies were analyzed, with a total population of 4.078 participants (3.369 FM and 709 individuals without FM). From a functional point of view, the 6MWT distance covered by the group of individuals without FM was significantly greater than that of the individuals with FM in all the analyzed studies. In addition, when comparing the results obtained in the gait pattern analysis, it was observed that individuals with FM walked slower, with a shorter stride length and lower cadence compare to individuals without FM.

Conclusions

It is possible to affirm that individuals with FM perform walking tests differently than individuals without FM. It was observed that individuals with FM walk performing a cycle of shorter length and lower frequency, producing a slower gait, which results in a shorter distance traveled, in the same period of time, with respect to healthy subjects.

An Observational Study Comparing Fibromyalgia and Chronic Low Back Pain in Somatosensory Sensitivity, Motor Function and Balance

Fibromyalgia (FM) and chronic low back pain (CLBP) have shared pathophysiology and have a considerable impact on patients' daily activities and quality of life. The main objective of this study was to compare pain impact, somatosensory sensitivity, motor functionality, and balance among 60 patients with FM, 60 patients with CLBP, and 60 pain-free controls aged between 30 and 65 years. It is essential to know the possible differences existing in symptomatology of two of the major chronic pain processes that most affect the population, such as FM and CLBP. The fact of establishing possible differences in sensory thresholds, motor function, and proprioceptive measures among patients with FM and CLBP could bring us closer to a greater knowledge of the chronic pain process. Through an observational study, a comparison was made between the three groups (FM, CLBP, and pain-free controls) evaluating functional performance, postural balance, kinematic gait parameters, strength, depression, fatigue, and sensitivity to pain and vibration. Patients with chronic pain showed worse somatosensory sensitivity (p < 0.001) and motor function (p < 0.001) than pain-free controls. Moreover, patients with FM showed greater pain impact (p < 0.001) and bigger somatosensory (p < 0.001) and motor deficiencies (p < 0.001) than patients with CLBP. Further research should explore the possible reasons for the greater deterioration in patients with FM in comparison with other chronic pain conditions. Our results, showing the multiple areas susceptible of deterioration, make it necessary to adopt interdisciplinary interventions focused both on physical and emotional dysfunction.

Effects of Non-Pharmacological Treatment on Pain, Flexibility, Balance and Quality of Life in Women with Fibromyalgia: A Randomised Clinical Trial

Background: The functional deficits in people with fibromyalgia can be related to the level of physical activity performed. This study investigated the effectiveness of an active exercise programme versus exercise for well-being improving pain, flexibility, static balance, perceived exertion and quality of life of women with fibromyalgia; Methods: A randomised, single-blind, controlled trial was conducted. A total of 141 of women diagnosed with fibromyalgia were enrolled and randomised to an active exercise program group (n = 47), where they performed physical active exercises, an exercise for well-being group (n = 47), which performed the Qi Gong exercises named ‘the twenty Wang Ziping figures for health and longevity’, and a control group (n = 47), which did not receive any intervention, for a period of 4 weeks. Measures were taken at baseline and after the treatment. The primary outcome measures were static balance and centre of gravity (Wii-Fit Nintendo ©), flexibility (test de Wells and Dillon), pain (Visual Analogue Scale) and quality of life (Spanish-Fibromyalgia Impact Questionnaire). The secondary outcome measure was the perceived exertion during activity (BORG Scale). Results: In total, 93 participants completed the study. The mean value of the age was 52.24 ± 6.19. The post intervention results showed statistically significant improvements in the exercise for well-being and the active exercise programme groups vs. the control group in relation to pain (p = 0.006 active exercise programme group, p = 0.001 exercise for well-being group), static balance (p < 0.001 active exercise programme group) and quality of life (p < 0.001 active exercise programme group, p = 0.002 exercise for well-being group). In addition, the mean scores related to perceived fatigue during the sessions were 6.30 ± 1.88 for the active exercise programme group and 5.52 ± 1.55 for the exercise for well-being group. These differences were not significant. Conclusions: The active exercise program and exercise for well-being improved flexibility, static balance, pain and quality of life of women with fibromyalgia. The participants of the active exercise programme achieved better results that those of the exercise for well-being.

Age-Related Changes in Centre of Pressure Trajectories Analysed with a Novel 'Return to Central' Analysis

To evaluate age and fall-risk related changes in balance ability from measures of bipedal quiet stance, this study aims to investigate the characteristics of 'return to central' - Centre of Pressure (COP) trajectories. COP trajectories were extracted from 60-second COP recordings in bipedal stance. In anterior posterior direction, age was associated with a greater number of detected trajectories, increased velocity and more stringent control. No differences related to fall risk were established or to age or fall risk in mediolateral direction. The characteristics 'return to central' COP trajectories provided insight into the working of the postural control system and can be further developed for application if testing balance under challenging conditions is too risky.

Joint Assessment of Equilibrium and Neuromotor Function: A Validation Study in Patients with Fibromyalgia

OBJECTIVE

To develop and validate a tool for evaluating balance and neuromotor function in patients with fibromyalgia (FMS).

METHODS

Brainstorming, the nominal group technique, and pilot-testing were used to select a battery of 20 functional balance tests that were included in a screening tool. A total of 108 subjects (62 with fibromyalgia syndrome, 22 aged over 65 years, and 24 healthy subjects) participated in this validation study. Factor validity, internal consistency, the ability to discriminate between patients and healthy subjects, and concurrent validity with the Fibromyalgia Impact Questionnaire (FIQ), the Central Sensitization Inventory (CSI), the 12-Item Short-Form Health Survey (SF-12), and other tools for measuring balance, such as the Dizziness Handicap Inventory (DHI), the Activities-Specific Balance Confidence Scale (ABC-16), the Falls Efficacy Scale-International (FES-I), and posturographic parameters, were evaluated.

RESULTS

The factorial analysis extracted four factors that explained 70% of the variance. The Alpha Cronbach value was 0.928. Concurrent validity of the screening tool with respect to other tools was high, and the receiver operating characteristic (ROC) curve analysis showed an AUC value of 0.932 for discriminating between healthy and FMS subjects. Severe balance disorder related to head movements in FMS patients was found.

CONCLUSION

The 20-item JAEN (Joint Assessment of Equilibrium and Neuro-motor Function) screening tool is a valid and reliable tool for assessing balance in patients with FMS.

Impaired Balance in Patients with Fibromyalgia Syndrome: Predictors of the Impact of This Disorder and Balance Confidence

Patients with fibromyalgia syndrome (FMS) have a nonspecific postural balance disorder and a greater prevalence of falls. Objective: to clarify which aspects of maintaining balance are associated with the impact of the disorder and with balance confidence. Methods: A total of 182 persons with FMS agreed to participate in this study. After re-evaluation, 57 fully met inclusion criteria: age 40–70 years and moderate-severe impact of the illness according to the Fibromyalgia Impact Questionnaire (FIQ). All participants underwent a posture control analysis with a stabilometric platform, an evaluation of the perception of verticality and an exploration of the vestibular system via functional tests. Additionally, they self-completed questionnaires about balance confidence, central sensitization, pain catastrophizing, kinesiophobia, dizziness and days with episodes of instability. Results: The FIQ was associated with central sensitization and dizziness, which explained 56% of its variance (AdjR2 = 0.566), while days with instability, kinesiophobia and dizziness also explained more than half of the variance of the balance confidence scale (AdjR2 = 0.527). A high percentage of positive responses was found for functional tests (>50%) and a high dispersion in the stabilometric parameters. Conclusion: the detection of factors susceptible to intervention, such as disability due to dizziness, takes on special relevance in patients with FMS.

Principles of the Guidance of Exploration for Orientation and Specification of Action

To control movement of any type, the neural system requires perceptual information to distinguish what actions are possible in any given environment. The behavior aimed at collecting this information, termed "exploration", is vital for successful movement control. Currently, the main function of exploration is understood in the context of specifying the requirements of the task at hand. To accommodate for agency and action-selection, we propose that this understanding needs to be supplemented with a function of exploration that logically precedes the specification of action requirements with the purpose of discovery of possibilities for action-action orientation. This study aimed to provide evidence for the delineation of exploration for action orientation and exploration for action specification using the principles from "General Tau Theory." Sixteen male participants volunteered and performed a laboratory-based exploration task. The visual scenes of different task-specific situations were projected on five monitors surrounding the participant. At a predetermined time, the participant received a simulated ball and was asked to respond by indicating where they would next play the ball. Head movements were recorded using inertial sensors as a measure of exploratory activity. It was shown that movement guidance characteristics varied between different head turns as participants moved from exploration for orientation to exploration for action specification. The first head turn in the trial, used for action-orientation, showed later peaks in the velocity profile and harder closure of the movement gap (gap between the start and end of the head-movement) in comparison to the later head turns. However, no differences were found between the first and the final head turn, which we hypothesized are used mainly for action orientation and specification respectively. These results are in support of differences in the function and control of head movement for discovery of opportunities for action (orientation) vs. head movement for specification of task requirements. Both are important for natural movement, yet in experimental settings,orientation is often neglected. Including both orientation and action specification in an experimental design should maximize generalizability of an experiment to natural behavior. Future studies are required to study the neural bases of movement guidance in order to better understand exploration in anticipation of movement.

Influence of age and falls incidence on tau guidance of centre of pressure movement during gait initiation

BACKGROUND

Prospective balance control can be assessed in terms of the characteristics of a tau-guidance function that summarizes the velocity profile of Centre of Pressure (CoP) movement during gait initiation. This allows the nature of CoP movement to be assessed on a continuum between controlled 'soft'- and unstable 'hard' CoP-motion gap-closure. Previous research has shown less stable movement patterns with harder closures with increasing age, which makes movements more prone to overshooting and could possibly explain the increasing falls risk with age.

RESEARCH QUESTIONS

The primary research question was 'what is the relationship between falls incidence and tau-guidance in the mediolateral centre of pressure movements during gait initiation?' The secondary research question was 'what are the influences of age and task demands on the variability of tau-guidance characteristics?'.

METHODS

Sixteen young adults and 76 older adults performed 33 gait initiations from a force platform, stepping onto stepping-targets imposing differing task demands. Older participants completed a one-year follow-up screening for falls. An analysis was performed investigating linear relationships between a tau-guidance function and the time-to-closure (tau) of the mediolateral centre of pressure motion-gap with coupling constant K (dependent variable).

RESULTS

Gait-related falls during the 12-month follow-up period were associated with higher tau-K values. Furthermore, longer movement preparation time was associated with lower K values, particularly in fallers. Previously-reported age-related increases of the tau-coupling constant values which were found in studies of unconstrained gait initiation were not present in our results.

SIGNIFICANCE

The presence of the targeting task provided a more prescriptive environment compared to unconstrained gait initiation and could explain the absence of age-related changes to the produced K values. Falls incidence was found to be associated with higher values of K, indicating less stable movement. Future studies should investigate the practical implications of these findings for falls prevention.

Impaired Trunk Posture in Women With Fibromyalgia

STUDY DESIGN

A cross-sectional study.

OBJECTIVES

The main goal of the study was to analyze posture of Fibromyalgia syndrome (FMS) in women compared with healthy subjects to establish if posture assessment could be useful to characterize the syndrome. Secondarily, we explored the impact of sedentary behavior on trunk posture.

SUMMARY OF BACKGROUND DATA

Pain has been associated with poor static postures, however there is little information on the effect of FMS, which is characterized by widespread pain, on trunk posture.

METHODS

One hundred eighteen women with FMS and 110 healthy counterparts participated in this study, in which trunk posture was assessed. The thoracic kyphosis, forward head position, and shoulder position (basal and maximum protraction) were measured. Further, maximum shoulder protraction and the ability to maintain the cervical and thoracic angle were assessed. To compare the differences in posture depending on the grouping, an independent Student t test was conducted. To analyze the differences between groups in the ability to maintain the position over a period of time and the differences in posture depending on more or less active lifestyles, two multivariate analysis of variance were performed.

RESULTS

The results showed a significantly larger thoracic kyphosis, baseline shoulder protraction and lower craniovertebral angle and maximum protraction in FMG compared with CG (P < 0.05). FMG subjects exhibited an impaired ability to maintain the cervical and thoracic angles, as this varied throughout the test, unlike those of their counterparts. A sedentary lifestyle did not affect trunk posture in the FMS participants.

CONCLUSION

FMS female population present an altered trunk posture and an inability to maintain trunk position. Since this does not appear to be influenced by a more or less active lifestyle, specific treatment programs are needed to manage this clinical condition.

LEVEL OF EVIDENCE

2.

A Concurrent Cognitive Task Does Not Perturb Quiet Standing in Fibromyalgia and Chronic Fatigue Syndrome

Background and Objectives

Cognitive complaints are common in fibromyalgia (FM) and chronic fatigue syndrome (CFS). Fatigue as well as pain may require greater effort to perform cognitive tasks, thereby increasing the load on processing in the central nervous system and interfering with motor control.

Methods

The effect of a concurrent arithmetic cognitive task on postural control during quiet standing was investigated in 75 women (aged 19–49 years) and compared between FM, CFS, and matched controls (n=25/group). Quiet standing on a force plate was performed for 60 s/condition, with and without a concurrent cognitive task. The center of pressure data was decomposed into a slow component and a fast component representing postural sway and adjusting ankle torque.

Results

Compared to controls, CFS and FM displayed lower frequency in the slow component (p < 0.001), and CFS displayed greater amplitude in the slow (p=0.038 and p=0.018) and fast (p=0.045) components. There were no interactions indicating different responses to the added cognitive task between any of the three groups.

Conclusion

Patients displayed insufficient postural control across both conditions, while the concurrent cognitive task did not perturb quiet standing. Fatigue but not pain correlated with postural control variables.

Lower regulatory frequency for postural control in patients with fibromyalgia and chronic fatigue syndrome

As many similar symptoms are reported in fibromyalgia (FM) and chronic fatigue syndrome (CFS), underlying defcits may potentially also be similar. Postural disequilibrium reported in both conditions may thus be explained by similar deviations in postural control strategies. 75 females (25/group FM, CFS and control, age 19-49 years) performed 60 s of quiet standing on a force platform in each of three conditions: 1) firm surface with vision, 2) firm surface without vision and, 3) compliant surface with vision. Migration of center of pressure was decomposed into a slow and a fast component denoting postural sway and lateral forces controlling postural sway, analyzed in the time and frequency domains. Main effects of group for the antero-posterior (AP) and medio-lateral (ML) directions showed that patients displayed larger amplitudes (AP, p = 0.002; ML, p = 0.021) and lower frequencies (AP, p < 0.001; ML, p < 0.001) for the slow component, as well as for the fast component (amplitudes: AP, p = 0.010; ML, p = 0.001 and frequencies: AP, p = 0.001; ML, p = 0.029) compared to controls. Post hoc analyses showed no significant differences between patient groups. In conclusion, both the CFS- and the FM-group differed from the control group. Larger postural sway and insufficient control was found in patients compared to controls, with no significant differences between the two patient groups.

Static postural sway of women with and without fibromyalgia syndrome: A cross-sectional study

BACKGROUND

There is a frequent complaint about balance problems among fibromyalgia syndrome patients; however, there are not enough studies that have shown static postural sway of women with fibromyalgia syndrome. This study aimed to compare static postural sway of women with and without fibromyalgia syndrome.

METHODS

This is a cross-sectional study in which twenty-nine women with fibromyalgia syndrome and 20 without took part. A posturography evaluation was performed in six different situations (bipedal, right tandem and left tandem, with eyes opened and closed), and questionnaires for clinical depression symptoms, clinical anxiety symptoms, sleep quality, and Visual Analogue Scales for Pain and Fatigue were applied. Mann-Whitney U test was used to check differences among groups; Wilcoxon matched-pair test was used to check differences intragroup; Cohen d coefficient was used to measure effect sizes and Pearson Correlation Coefficient was used for correlations among variables. Level of significance adopted was 5%.

FINDINGS

Women with fibromyalgia syndrome have presented worse postural sway than women without fibromyalgia syndrome in all situations (P<0.05), and worse scores in all questionnaires (P<0.05). In the eyes closed situations, women with fibromyalgia syndrome presented worse postural sway than women without in the same conditions.

INTERPRETATION

Women with fibromyalgia syndrome have worse performance in the static posture test, more prominent in reduced support bases with eyes closed. Pain, fatigue, depression and anxiety may have directly influenced postural sway in fibromyalgia syndrome patients.

Gross and fine motor function in fibromyalgia and chronic fatigue syndrome

Purpose

This paper aimed to investigate motor proficiency in fine and gross motor function, with a focus on reaction time (RT) and movement skill, in patients with fibromyalgia (FM) and chronic fatigue syndrome (CFS) compared to healthy controls (HC).

Methods

A total of 60 individuals (20 CFS, 20 FM, and 20 HC), age 19–49 years, participated in this study. Gross motor function in the lower extremity was assessed using a RT task during gait initiation in response to an auditory trigger. Fine motor function in the upper extremity was measured during a precision task (the Purdue Pegboard test) where the number of pins inserted within 30 s was counted.

Results

No significant differences were found between FM and CFS in any parameters. FM and CFS groups had significantly longer RT than HC in the gait initiation (p=0.001, and p=0.004 respectively). In the Purdue Pegboard test, 20% in the FM group, 15% in the CFS groups, and 0% of HC group, scored below the threshold of the accepted performance. However, there were no significant differences between FM, CFS, and HC in this task (p=0.12).

Conclusion

Compared to controls, both CFS and FM groups displayed significantly longer RT in the gait initiation task. Generally, FM patients showed the worst results in both tests, although no group differences were found in fine motor control, according to the Purdue Pegboard test.