Persons with recurrent low back pain exhibit a rigid postural control strategy

Specific Contribution of the Transversus Abdominis for Postural Control Against Perturbation Caused by Kinesthetic Illusion

Functional independence of the transversus abdominis (TrA) from other trunk muscles for postural control is still unclear. This study aimed to clarify the specific function of the TrA to control standing posture by vibratory stimulation of the triceps surae. Fifteen men participated in this study. Muscle activity of the TrA, internal oblique, lumbar multifidus, gluteus maximus, rectus femoris, biceps femoris, gastrocnemius, and tibialis anterior was measured using fine-wire and surface electrodes. Participants were asked to maintain a quiet standing posture with and without vibration of the triceps surae, which induced a kinesthetic illusion and the concomitant backward sway of the body. The muscle activity of each muscle for 10 s was extracted with and without vibration. The muscle activity levels were compared between the conditions by a paired t-test or Wilcoxon signed-rank test. The activity of the TrA and rectus femoris was increased, whereas the internal oblique showed no change as a result of the induced kinesthetic illusion. In addition, the activity of the multifidus and biceps femoris was decreased. The TrA and rectus femoris could contribute to control the backward sway of the body. Furthermore, the TrA may have functional independence from the internal oblique during standing postural control. These results warrant further study in patients with low back pain.

Effects of unstable load and unstable surface ontrunk muscles activation and postural control in healthy subjects

Exercise with an unstable load is considered a new training method to activate the core muscles. Research has shown consistency regarding an unstable surface but has not provided comprehensive findings about the effect of an unstable load. The study aimed to examine the impact of an unstable load and unstable surfaces on core muscle activation and postural control during lifting. Thirty-eight participants lifted a load equivalent to 10 % of their body weight under three conditions: a stable load on an unstable surface, a stable load on a stable surface, and an unstable load on a stable surface. The center of pressure (COP) displacement and electromyography activity of abdominal and back extensor muscles were measured during lifting. The results indicated that lifting on an unstable surface activated the lumbar erector spinae and multifidus muscles more than in a stable condition (P<0.05). However, there was no significant difference in the level of thoracic erector spinae muscle activity between the unstable load and unstable surface conditions. The stable condition increased activity in the internal oblique muscle (1.37 times) compared to the unstable conditions. The analysis of postural control revealed that lifting the load on an unstable surface significantly decreased COP displacement in the anteroposterior direction (P<0.05), while holding the load on the unstable surface significantly increased COP displacement in the anteroposterior direction compared to the other conditions. These findings could be valuable for future rehabilitation research, learning appropriate lifting techniques, and setting specific training goals in sports.

Effectiveness of 12-Week Core Stability Training on Postural Balance in Soccer Players With Groin Pain: A Single-Blind Randomized Controlled Pilot Study

BACKGROUND

Core stability training (CST) is effective in improving postural balance, core endurance, and self-reported outcomes in different populations. This study aimed to investigate the effect of CST in soccer players with groin pain (GP).

HYPOTHESIS

CST would improve postural balance performance, core endurance, and self-reported outcomes in soccer players with GP.

STUDY DESIGN

Randomized controlled trial.

LEVEL OF EVIDENCE

Level 2.

METHODS

Soccer players with GP who met the selection criteria were assigned randomly to a CST (CSTG, n = 10) or a control (CG, n = 10) group. The CG undertook no additional physical activity program besides their usual training. The CSTG performed a 12-week CST comprising 76 ~75 min sessions. Static (force platform) and dynamic (Y-Balance test) postural balance, core endurance (McGill trunk endurance tests), and self-reported outcomes (Copenhagen Hip and Groin Outcome Score [HAGOS]) were assessed before and immediately after the 12-week CST.

RESULTS

Significant improvements were seen in dynamic postural balance (P = 0.04 to <0.01), HAGOS scores (P = 0.02 to <0.01), and core endurance measures (P < 0.01) in the CSTG in posttest compared with pretest session and compared with CG. Static bipedal postural balance measures showed significant improvements (eyes open, P = 0.02; eyes closed, P < 0.01) in the CSTG in posttest compared with pretest session. However, no significant differences (P > 0.05) were observed between CSTG and CG after the training period.

CONCLUSION

A 12-week CST improved static (foam surface) and dynamic postural balance, core endurance measures, and HAGOS scores.

CLINICAL RELEVANCE

The beneficial effect of CST on improving postural balance, core endurance, and self-reported outcomes in soccer players with GP suggests that this training would be an important feature of rehabilitation programs for these players. Coaches and clinicians should prioritize CST training when designing rehabilitation programs.

Acute effect of dry needling on trunk kinematics and balance of patients with non-specific low back pain

BACKGROUND

Limited knowledge exists about the effectiveness of dry needling (DN) concerning the torso kinematics in patients with non-specific low back pain (NS-LBP). Acute effects of DN in NS-LBP patients from a functional perspective were investigated.

METHODS

Sixteen NS-LBP patients and 11 healthy individuals (HG) were examined. NS-LBP patients received a single session of DN at the lumbar region. Baseline and immediate post-treatment measurements during flexion-extension and lateral bending of the trunk were conducted for the NS-LBP patients. HG were measured only at baseline to be used as a reference of NS-LBP patients' initial condition. Algometry was applied in NS-LBP patients. Centre of pressure, range of motion of the trunk and its' derivatives were obtained.

FINDINGS

HG performed significantly faster, smoother and with greater mobility in the performed tasks compared to the pre intervention measurements of the NS-LBP patients. For the NS-LBP patients, significant greater angular velocity in frontal plane and significant lower jerk in the sagittal plane were demonstrated post intervention. DN alleviated pain tolerance significantly at the L5 level. Regarding the effectiveness of the DN upon spine kinematics, their derivatives were more sensitive.

INTERPRETATION

It appeared that the pathological type of torso movement was acutely affected by DN. NS-LBP patients showcased smoother movement immediately after the intervention and better control as imprinted in the higher derivative of motion although range of motion did not improve. This quantitative variable may not be subjected to acute effects of DN but rather need additional time and training to be improved.

Examining the influence of body fat distribution on standing balance and functional performance in overweight female patients with degenerative lumbar disease

Introduction: Degenerative lumbar disease (DLD) is a prevalent disorder that predominantly affects the elderly population, especially female. Extensive research has demonstrated that overweight individuals (categorized by body fat distribution) have a higher susceptibility to developing DLD and an increased risk of falling. However, there is limited research available on the standing balance and functional performance of overweight females with DLD. Aims: To determine the impact of body fat distribution on standing balance and functional performance in overweight females with DLD. Methods: This cross-sectional study evaluated thirty females with DLD were categorized into three types of body fat distribution based on body mass index (BMI) and waist-hip ratio, specifically as android-type, gynoid-type, and normal weight groups. In addition, a control group of ten age-matched females with normal weight was recruited. The Visual Analogue Scale, Roland Morris Disability Questionnaire, Cobb angle (Determined using x-ray), and body composition (Determined using the InBody S10), were conducted only on the DLD groups. All participants were assessed standing balance in the anteroposterior and mediolateral directions. The functional assessments included timed-up-and-go and 5-times-sit-to-stand tests. Results: There were 10 people in each group. Android-type (Age = 65.00 ± 6.34 years; BMI = 26.87 ± 2.05 kg/m2), Gynoid-type (Age = 65.60 ± 4.99 years; BMI = 26.60 ± 1.75 kg/m2), Normal weight (Age = 65.70 ± 5.92 years; BMI = 22.35 ± 1.26 kg/m2), and Control (Age = 65.00 ± 5.23 years; BMI = 22.60 ± 1.12 kg/m2). The android-type group had higher body fat, visceral fat, and lower muscle mass (p < 0.05), along with an increased Cobb angle (p < 0.05). They showed greater ellipse area, total excursion, and mean distance in the anteroposterior direction (p < 0.05). During the functional performance assessments, the android-type group had longer durations in both the 5-times-sit-to-stand and timed-up-and-go tasks (p < 0.05). Conclusion: Our study found that android-type overweight individuals showed postural instability, reduced functional performance, and insufficient lower limb muscle strength and mass. These findings might help physical therapists in planning interventions, as they imply that patients with DLD may require specific types of standing balance training and lower extremities muscle-strengthening based on their body fat distribution. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT05375201.

Effects of non-specific low back pain on static balance in emerging adults

BACKGROUND

Postural control impairments in middle-aged or older people with chronic low back pain (CLBP) have been extensively documented. However, little is known about changes in postural control early in the disease process which may underlie compensatory movement strategies.

OBJECTIVE

Our purpose was to quantify postural sway and sensory weighting in emerging adults with and without CLBP.

METHODS

Nineteen emerging adults with CLBP (age = 18-26 years (21.11 ± 1.73)) and 19 matched peers without CLBP (18-27 years (22.20 ± 1.97)) participated in a cross-sectional study. Displacement of the center of mass during Quiet stance (QS), Tandem stance (TS), and Unilateral stance (US) on 2 surfaces (stable, unstable) were used to assess postural sway. Sensory Organization Test (SOT) was used to assess sensory weighting.

RESULTS

Emerging adults with CLBP showed large, significant increases in postural sway during unstable TS (p ≤ .020). Participants with CLBP relied more on somatosensory input, as evidenced by lower equilibrium scores during conditions favoring visual (p = .020) or vestibular (p < .001) input during the SOT.

CONCLUSION

Emerging adults with CLBP showed postural control impairments related to altered sensory weighting. These findings provide insights into the development of CLBP and its effects on postural control. This information may aid early identification, monitoring, and treatment of individuals in the initial stages of disease development who may have unrecognized postural impairments.

Virtual reality skateboarding training for balance and functional performance in degenerative lumbar spine disease

BACKGROUND

Degenerative lumbar spine disease (DLD) is a prevalent condition in middle-aged and elderly individuals. DLD frequently results in pain, muscle weakness, and motor impairment, which affect postural stability and functional performance in daily activities. Simulated skateboarding training could enable patients with DLD to engage in exercise with less pain and focus on single-leg weight-bearing. The purpose of this study was to investigate the effects of virtual reality (VR) skateboarding training on balance and functional performance in patients with DLD.

METHODS

Fourteen patients with DLD and 21 age-matched healthy individuals completed a 6-week program of VR skateboarding training. The motion capture and force platform systems were synchronized to collect data during a single-leg stance test (SLST). Musculoskeletal simulation was utilized to calculate muscle force based on the data. Four functional performance tests were conducted to evaluate the improvement after the training. A Visual Analogue Scale (VAS) was also employed for pain assessment.

RESULTS

After the training, pain intensity significantly decreased in patients with DLD (p = 0.024). Before the training, patients with DLD took longer than healthy individuals on the five times sit-to-stand test (p = 0.024). After the training, no significant between-group differences were observed in any of the functional performance tests (p > 0.05). In balance, patients with DLD were similar to healthy individuals after the training, except that the mean frequency (p = 0.014) was higher. Patients with DLD initially had higher biceps femoris force demands (p = 0.028) but shifted to increased gluteus maximus demand after the training (p = 0.037). Gluteus medius strength significantly improved in patients with DLD (p = 0.039), while healthy individuals showed consistent muscle force (p > 0.05).

CONCLUSION

This is the first study to apply the novel VR skateboarding training to patients with DLD. VR skateboarding training enabled patients with DLD to achieve the training effects in a posture that relieves lumbar spine pressure. The results also emphasized the significant benefits to patients with DLD, such as reduced pain, enhanced balance, and improved muscle performance.

Lack of Proprioceptive Strategy Modulation Leads to At-Risk Biomechanics for Anterior Cruciate Ligament in Healthy Athletes

INTRODUCTION

Anterior cruciate ligament (ACL) injuries are frequent in handball, and altered sensory integration may contribute to increased injury risk. Recent evidence showed that proprioceptive postural control strategies differ among athletes. The aim of this study was to evaluate the relationship between proprioceptive strategy and biomechanics during side-cutting maneuvers.

METHODS

A total of 47 handball players performed anticipated and unanticipated cutting tasks. Their postural proprioceptive strategy was then characterized according to the perturbation of the center of pressure displacement generated by the muscle vibration on a firm and foam surface. Individuals able to reweight proprioception from ankle to lumbar signals according to the stability of the support were defined as flexible. Conversely, athletes maintaining an ankle-steered strategy on foam surface were characterized as rigid. Statistical parametric mapping analysis was used to compare pelvic and lower limb side-cutting kinematics, kinetics, and EMG activity from seven muscles 200 ms before and after initial contact (IC) using a two-way ANOVA (group-condition).

RESULTS

Twenty athletes (11 females and 9 males, 18.5 yr) were characterized as flexible and 20 athletes (12 females and 8 males, 18.9 yr) as rigid. No interaction between condition and proprioceptive profile was observed. More ipsilateral pelvic tilt before IC and lower vastus lateralis (VL) activity immediately after IC was observed during CUT ant . When comparing proprioceptive strategy, rigid individuals exhibited less preactivity of the semitendinosus ( P < 0.001) and higher VL activity ( P = 0.032). Conversely, rigid showed higher gluteus medius preactivity ( P < 0.05) and higher VL activity 100 ms after IC ( P < 0.001). Ankle was also more internally rotated before and during the stance phase ( P < 0.05) among rigid athletes.

CONCLUSIONS

Rigid handball players exhibited at-risk determinants for anterior cruciate ligament injuries during side-cutting maneuvers.

Association between central sensitization, pain sensitivity and balance control in patients with migraine

BACKGROUND

Balance alterations are prevalent among pain conditions, including migraine. The mechanisms explaining the association between pain and balance are unclear, as well as whether levels of pain sensitivity correlate with impaired balance. Our aim was therefore to investigate the association between balance, central sensitization symptoms and pain sensitivity in patients with migraine.

METHODS

This cross-sectional study included 50 patients and demographic, clinical information, central sensitization inventory (CSI) and pain catastrophizing (PCS) scores were obtained. Patients underwent a standardized protocol evaluating balance and pain thresholds for cold (CPT), heat (HPT), mechanical (MPT) and pressure (PPT) in trigeminal (V1) and extra-trigeminal (C6) dermatomes. Data were analysed using Person's correlation, linear regression models and contrasting the presence and absence of central sensitization symptoms through T-tests.

RESULTS

Mild-to-moderate correlations were observed between balance and MPT in V1 (r = -0.24, p = 0.046) and C6 (r = -0.41, p = 0.002), CPT in V1 (r = 0.31, p = 0.026), CSI scores (r = 0.27, p = 0.029) and migraine frequency (r = 0.25, p = 0.040). Balance was explained by CPT and MPT (R2 = 0.32, p = 0.001). The variance of CSI was explained by PCS scores and balance (R2 = 0.28, p = 0.001). Patients with symptoms of central sensitization presented an increased balance impairment (p = 0.044) and higher catastrophizing levels (p = 0.001) in contrast to patients without symptoms.

CONCLUSION

Balance impairment is associated with reduced pain thresholds and higher CSI scores. These results may help to elucidate the aetiology of balance alterations among chronic pain conditions.

SIGNIFICANCE

For the first time, it has been shown that balance alterations can reflect greater pain sensitivity and signs of central sensitization in patients with migraine. This opens up perspectives for future studies to understand the mechanisms and further factors associated with balance and pain sensitivity in migraine.

The associations between lumbar proprioception and postural control during and after calf vibration in people with and without chronic low back pain

The relationships of lumbar proprioception with postural control have not been clarified in people with chronic low back pain. This study aimed to compare the associations between lumbar proprioception and postural control in response to calf vibration in individuals with and without chronic low back pain. In this study, we recruited twenty patients with chronic low back pain (CLBP group) and twenty healthy control subjects (HC group) aged between 18 and 50 years. This study was a cross-sectional study and completed from May 2022 to October 2022. The passive joint repositioning sense (PJRS) test for two positions (15° and 35°) were used to assess lumbar proprioception and expressed as the mean of reposition error (RE). Postural control was tested by adding and removing calf vibration while standing on a stable force plate with eyes closed. The sway velocity in the anterior-posterior (AP) direction of center of pressure (COP) data with a window of 15s epoch at baseline, during and after calf vibration was used to evaluate postural control. Mann-Whitney U-tests were used to compare the difference of lumbar proprioception between two groups, and the independent t-tests were used to compare the difference of postural control at baseline and during vibration, and a mixed design ANOVA was used to compare the difference of postural control during post-perturbation. In addition, to explore the association between postural control and lumbar proprioception and pain intensity, Spearman's correlations were used for each group. The major results are: (1) significantly higher PJRS on RE of 15° (CLBP: 95% CI [2.03, 3.70]; HC: 95% CI [1.03, 1.93]) and PJRS on RE of 35° (CLBP: 95% CI [2.59, 4.88]; HC: 95% CI [1.07, 3.00]) were found in the CLBP group; (2) AP velocity was not different between the CLBP group and the HC group at baseline and during calf vibration. However, AP velocity was significantly larger in the CLBP group compared with the HC group at epoch 2-14 after calf vibration, and AP velocity for the CLBP group took a longer time (23 epochs) to return to the baseline after calf vibration compared with the HC group (9 epochs); (3) lumbar proprioception represented by PJRS on RE of 15°correlated negatively with AP velocity during and after vibration for the HC group. Within the CLBP group, no significant relationships between PJRS on RE for two positions (15° and 35°) and AP velocity in any postural phases were found. In conclusion, the CLBP group has poorer lumbar proprioception, slower proprioceptive reweighting and impaired postural control after calf vibration compared to the HC group. Lumbar proprioception offers different information on the control strategy of standing control for individuals with and without CLBP in the situations with proprioceptive disturbance. These results highlight the significance of assessing lumbar proprioception and postural control in CLBP patients.

Effect of dynamic neuromuscular stabilization training using the inertial load of water on functional movement and postural sway in middle-aged women: a randomized controlled trial

BACKGROUND

Chronic stress and diseases occur more frequently in middle-aged compared to younger women and this is often the result of physical, psychological and socio-economic changes. These health consequences reduce lower body muscle mass and flexibility, leading to generalized impairments in functional movement and balance. Dynamic Neuromuscular Stabilization (DNS) training using the inertial load of water is known for its positive impact on functional strength improvement and muscle stabilization.

OBJECTIVE

This study aimed to determine the effect of DNS training using inertial water loads on functional movement and postural sway in middle-aged women.

METHOD

A sample of 24 middle-aged women participated in the study and were randomly divided into two groups: the experimental group, n = 12 (age: 58.33 ± 1.48 yrs, height: 162.16 ± 1.27 cm, weight: 61.77 ± 2.21 kg) and control group, n = 12 (age: 59.58 ± 1.13 yrs, height: 160.1 ± 1.13 cm, weight: 57.51 ± 1.12 kg). Center of Pressure (COP), moving distance, Root Mean Square (RMS), movement area and Functional Movement Screen (FMS) were conducted and analyzed pre- and post-examination. Participants engaged in the DNS training regimen, which utilized the inertial load of water, for 60 min each session, conducted twice weekly for 12 weeks.

RESULTS

There were significant differences in the COP distance (p < 0.001), RMS (p < 0.05), COP area and FMS test (p < 0.001) in the pre-post comparison of each group. And significant differences were found in COP distance (p < 0.05), RMS (p < 0.05), COP area (p < 0.05) and FMS test (p < 0.05) between groups. The DNS training improved the dynamic stability of single-leg standing, torso stability and functional movement in middle-aged women.

CONCLUSION

DNS training programs using the inertial load of water have been shown to be effective in movement improvement and posture retention ability, which is beneficial for functional movement, equilibrium strategy, and dynamic stability of middle-aged women. Furthermore, the DNS training method designed in this study can be useful for trainees who require posture correction in a safe and effective way regardless of their age and gender.

Comparisons of postural control, proprioception, muscle strength, pain and disability between individuals with acute, subacute and chronic low back pain

PURPOSE/AIM

Postural control, proprioception and lower extremity muscle strength are affected in individuals with low back pain (LBP). However, it is yet unknown whether these variables differentiate between acute, subacute and chronic stages of LBP. The aim was to investigate if there were any differences in postural control, proprioception, lower extremity muscle strength, pain intensity and disability between individuals in the different stages of LBP.

MATERIALS AND METHODS

In this cross-sectional study, 124 individuals with LBP were grouped as acute LBP (ALBP) (n = 38), subacute LBP (SLBP) (n = 30) and chronic LBP (CLBP) (n = 56) groups. Postural control was assessed via computerised technology. Lumbar proprioception, lower extremity muscle strength, pain intensity and disability were assessed using Joint Repositioning Error Test, hand-held dynamometer, Numeric Rating Scale and Oswestry Disability Index (ODI), respectively. Kruskal-Wallis Tests, ANCOVA and post hoc Mann-Whitney U-Test with Bonferroni correction were performed.

RESULTS

While there were no significant differences in terms of postural control, proprioception and pain intensity (p > 0.05), significant differences were found in terms of lower extremity muscle strength and ODI scores between groups when adjusted for age (p < 0.05). Individuals with CLBP demonstrated poorer lower extremity muscle strength than those with ALBP and SLBP, and higher disability than those with ALBP (p < 0.017).

CONCLUSIONS

Although postural control, proprioception and pain intensity were similar between individuals with acute, subacute and chronic LBP, muscle strength and disability seem to worsen stepwise as the pain becomes chronic. Muscle strength and disability should be taken into account while evaluating and/or managing individuals with acute and subacute stages of LBP.

People With Low Back Pain Exhibit Higher Trunk Muscle Activity and Impaired Postural Control During Static and Dynamic Functional Tasks: A Cross-Sectional Study

The study compared superficial trunk muscle activity and postural control among an active extension subgroup of people with nonspecific chronic low back pain (AE-NSCLBP) with painfree controls during functional tasks. Thirty-two people (17 people with low back pain [LBP] and 15 painfree controls) participated in this study. Muscle activity of 5 trunk muscles and postural control were investigated during both standing tasks (eyes open/closed; single/double-leg balance) and dynamic functional tasks (spinal forward flexion and return, and a sit to stand transfer). Results showed that during single-leg standing, people with AE-NSCLBP exhibit higher muscle activity than painfree controls for 3 trunk muscles, especially with their eyes closed. There were no significant differences in muscle activity between eye conditions during double-leg standing and sit to stand transfer, forward flexion, and return from flexion. The AE-NSCLBP subgroup also demonstrated significantly impaired postural control (lower time to boundary) in 4 of 8 conditions, especially during single-leg standing and with their eyes closed. These findings show people with LBP typically demonstrated greater trunk muscle activity and poorer postural control while maintaining standing posture. This pattern was most evident when the postural challenge was higher, such as single-leg standing or with eyes closed. While this study design cannot infer causality, these findings have implications for LBP rehabilitation, particularly regarding approaches which seek to alter muscle activation among people with LBP.

Investigating the Effect of Addition of Cervical Proprioceptive Training to Conventional Physiotherapy on Visual, Vestibular and Proprioceptive Dependency of Postural Control in Patients with Chronic Non-Specific Neck Pain: A Randomized Controlled Clinical Trial

Objectives

While cervical proprioception deficit has been suggested as a contributing factor to clinical consequences of chronic non-specific neck pain (CNSNP), the effect of addressing such impairments on postural control strategies has remained unexplored. The aim of this study was to compare the response of the postural control system to alteration of sensory afferents in CNSNP with asymptomatic individuals. Furthermore, we examined whether proprioceptive training would yield superior outcomes to routine physiotherapy for improvement of postural control, pain and disability.

Methods

Center of pressure (CoP) variables of sixty CNSNP patients equally distributed in any of the proprioception-specific or conventional physiotherapy groups and 30 asymptomatic participants were evaluated under four standing conditions:1) normal, 2) foam, 3) cervical extension/eyes open and 4) cervical extension/eyes closed standing.

Results

CoP anteroposterior range and anteroposterior and mediolateral velocity in patients were significantly higher than the control group under condition 2 (P<0.05). Patients also demonstrated lower anteroposterior lyapunov exponent under conditions 2 and 4 (P<0.05). Both interventions significantly decreased anteroposterior range and anteroposterior velocity(P<0.05). Anteroposterior lyapunov exponent also increased under condition 2 (P<0.05).. After the interventions, CoP anteroposterior range and anteroposterior velocity were significantly lower in the proprioceptive exercise group than the conventional physiotherapy group (P<0.05). Anteroposterior lyapunov exponent was also significantly higher in the proprioceptive exercise group (P<0.05).This while there was no significant difference between these patients and control group participants in any of the CoP variables after intervention.

Conclusion

Our results rejected the hypothesis that impaired neck proprioception in the presence of CNSNP is compensated by overweighting other sources of sensory afferent information. The findings also revealed that while proprioceptive exercises successfully returned postural strategies of CNSNP patients to those in asymptomatic participants, they do not add to clinical recovery of these patients.

The effects of virtual reality training on postural sway and physical function performance on older women with chronic low back pain: A double-blind randomized clinical trial

BACKGROUND

Chronic low back pain (CLBP) is known as an important debilitating health condition among older women.

OBJECTIVE

This study aimed to evaluate the effects of eight-week virtual reality training (VRT) exercises on postural sway and physical function performance (PFP) among older women suffering from CLBP.

METHODS

Twenty-seven older women presenting with CLBP were randomized into experimental and control groups. The experimental group was instructed to perform 30-minute VRT exercises three times a week for eight weeks. Plantar pressure variables [sway velocity (SV) and anterior-posterior (AP) and medial-lateral (ML) fluctuations of the center of pressure (CoP)], 30-second chair stand test (30CST), and timed up and go (TUG) test were recorded.

RESULTS

The VRT group exhibited significant decreases in SV (p= 0.002), AP (p= 0.008), and ML (p= 0.02) fluctuations. Also, the performance of the VRT group in the 30CST and TUG tests significantly improved after the exercises (P< 0.001).

CONCLUSION

According to the results, VRT and the program used in this study should be used to enhance balance and PFP in older women with CLBP who mostly prefer activities that are accessible and feasible in low-risk environments.

Combined Rehabilitation with Alpha Lipoic Acid, Acetyl-L-Carnitine, Resveratrol, and Cholecalciferolin Discogenic Sciatica in Young People: A Randomized Clinical Trial

Background and Objectives: In the Western world, back pain and sciatica are among the main causes of disability and absence from work with significant personal, social, and economic costs. This prospective observational study aims to evaluate the effectiveness of a rehabilitation program combined with the administration of Alpha Lipoic Acid, Acetyl-L-Carnitine, Resveratrol, and Cholecalciferol in the treatment of sciatica due to herniated discs in young patients in terms of pain resolution, postural alterations, taking painkillers, and quality of life. Materials and Methods: A prospective observational study was conducted on 128 patients with sciatica. We divided the sample into 3 groups: the Combo group, which received a combination of rehabilitation protocol and daily therapy with 600 mg Alpha Lipoic Acid, 1000 mg Acetyl-L-Carnitine, 50 mg Resveratrol, and 800 UI Cholecalciferol for 30 days; the Reha group, which received only a rehabilitation protocol; and the Supplement group, which received only oral supplementation with 600 mg Alpha Lipoic Acid, 1000 mg Acetyl-L-Carnitine, 50 mg Resveratrol, and 800 UI Cholecalciferol. Clinical assessments were made at the time of recruitment (T0), 30 days after the start of treatment (T1), and 60 days after the end of treatment (T2). The rating scales were as follows: the Numeric Rating Scale (NRS); the Oswestry Disability Questionnaire (ODQ); and the 36-item Short Form Health Survey (SF-36). All patients also underwent an instrumental stabilometric evaluation. Results: At T1, the Combo group showed statistically superior results compared to the other groups for pain (p < 0.05), disability (p < 0.05), and quality of life (p < 0.05). At T2, the Combo group showed statistically superior results compared to the other groups only for pain (p < 0.05) and quality of life (p < 0.05). From the analysis of the stabilometric evaluation data, we only observed a statistically significant improvement at T2 in the Combo group for the average X (p < 0.05) compared to the other groups. Conclusions: The combined treatment of rehabilitation and supplements with anti-inflammatory, pain-relieving, and antioxidant action is effective in the treatment of sciatica and can be useful in improving postural stability.

Effect of Adding Diaphragmatic Breathing Exercises to Core Stabilization Exercises on Pain, Muscle Activity, Disability, and Sleep Quality in Patients With Chronic Low Back Pain: A Randomized Control Trial

Objective

The purpose of this study was to test the effect of adding diaphragmatic breathing exercises (DBEs) to core stabilization exercises (CSEs) for patients with chronic low back pain (CLPB).

Methods

Twenty-two patients with CLPB were randomly allocated to the experimental (DBE + CSE) or control group (CSE only). They were given 12 treatment sessions 3 times a week for 4 weeks. Patients were evaluated before and after the 12 sessions. Surface electromyography of transverse abdominis, Oswestry Disability Index, Fear Avoidance Belief Questionnaire, Pittsburgh Sleep Quality Index, Numeric Pain Rating Scale, and chest expansion were used as outcome measures for pain, muscle activity, disability, and sleep quality.

Results

The outcome measure scores showed statistical significance of (P = .01) in time effect on muscle activity, sleep quality, disability score, pain score, fear-avoidance belief of patients and chest expansion; and group effect on Fear Avoidance Belief Questionnaire and physical activity parameter (P = .05). An interaction effect (time x group) on muscle activity for right transverse abdominus during tuck in (P = .01) and chest expansion (P = .01) was also found; however, no significant difference was found related to other parameters.

Conclusion

The combination of DBE and CSE interventions compared to CSE alone showed improvement in the measured parameters for patients with CLBP. Incorporating DBE with CSE also improved muscle activation and chest expansion.

Effects of External Abdominal Pressure Support on Dynamic Balance: A Randomized Crossover Study

Abdominal pressure is vital in protecting the lumbar spine and controlling postural balance. Dynamic balance is associated with movement stability, adaptation to load, and reduced injury risk. Although trunk stability has been examined using belts and braces, the effects of external abdominal pressure support (APS) on balance control remain unknown. In this study, we aimed to determine the effects of external APS on dynamic balance. Overall, 31 young adults participated in this randomized crossover study. External APS was provided using a device that could be pressurized and decompressed by inflating a cuff belt wrapped around the trunk. The modified Star Excursion Balance Test was performed under external APS and non-APS conditions. The maximum anterior, posterolateral, and posteromedial values normalized to the spinal malleolar distance and their respective composite values were compared between the two conditions with and without APS. Posterolateral, posteromedial, and composite values were significantly higher in the APS condition than in the non-APS condition (p < 0.001). The external APS was effective in immediately improving dynamic balance. Furthermore, APS was effective in dynamic balance control as it improved stability during anterior trunk tilt, which displaces the center of gravity forward.

Exploring the Interplay of Muscular Endurance, Functional Balance, and Limits of Stability: A Comparative Study in Individuals with Lumbar Spondylosis Using a Computerized Stabilometric Force Platform

Lumbar spondylosis, characterized by degenerative changes in the lumbar spine, often leads to pain, reduced spinal stability, and musculoskeletal dysfunction. Understanding the impact of lumbar spondylosis on musculoskeletal function, particularly lumbar extensor endurance, functional balance, and limits of stability, is crucial for improving the management and well-being of affected individuals. This study aimed to assess lumbar extensor endurance, functional balance, and limits of stability in individuals with lumbar spondylosis compared to age-matched healthy individuals and explore the correlations among these parameters within the lumbar spondylosis group. The lumbar spondylosis group consisted of 60 individuals initially screened by an orthopedician and referred to physical therapy. Age-matched healthy controls (n = 60) were recruited. Inclusion criteria encompassed adults aged 45-70 years for both groups. Lumbar extensor endurance was assessed using the Sorensen test, functional balance with the Berg Balance Scale, and limits of stability using a computerized stabilometric force platform. Lumbar extensor endurance was significantly lower in individuals with lumbar spondylosis compared to healthy controls (23.06 s vs. 52.45 s, p < 0.001). Functional balance, as assessed by the Berg Balance Scale, demonstrated a significant decrement in the lumbar spondylosis group (48.36 vs. 53.34, p < 0.001). Additionally, limits of stability variables, under both eyes-open and eyes-closed conditions, exhibited marked impairments in the lumbar spondylosis group (p < 0.001 for all variables). Within the lumbar spondylosis group, lumbar extensor endurance exhibited significant positive correlations with functional balance (0.46, p < 0.001) and negative correlations with limits of stability variables (r ranging from -0.38 to -0.49, p < 0.01 for all variables). This study underscores the significance of addressing lumbar extensor endurance, functional balance, and stability impairments in the comprehensive management of lumbar spondylosis.

PosturAll: A Posture Assessment Software for Children

From an early age, people are exposed to risk factors that can lead to musculoskeletal disorders like low back pain, neck pain and scoliosis. Medical screenings at an early age might minimize their incidence. The study intends to improve a software that processes images of patients, using specific anatomical sites to obtain risk indicators for possible musculoskeletal problems. This project was divided into four phases. First, markers and body metrics were selected for the postural assessment. Second, the software's capacity to detect the markers and run optimization tests was evaluated. Third, data were acquired from a population to validate the results using clinical software. Fourth, the classifiers' performance with the acquired data was analyzed. Green markers with diameters of 20 mm were used to optimize the software. The postural assessment using different types of cameras was conducted via the blob detection method. In the optimization tests, the angle parameters were the most influenced parameters. The data acquired showed that the postural analysis results were statistically equivalent. For the classifiers, the study population had 16 subjects with no evidence of postural problems, 25 with mild evidence and 16 with moderate-to-severe evidence. In general, using a binary classification with the train/test split validation method provided better results.

Discriminative Changes in Sitting and Standing Postural Steadiness in Patients With Chronic Low Back Pain

Postural control is reduced in patients with low back pain (LBP), which is considered an important factor attributing to the chronicity of LBP and a target for treatment. It is proposed that the changes in postural steadiness in sitting reflect the trunk control better than those in standing, but the previous study results are inconsistent. Thus, this study aimed to compare trunk sway parameters during standing and sitting between patients with chronic LPB (CLBP) and controls using a tracker-based posturography to record the trunk displacement trajectories at the lumbar level (TD [Formula: see text]. A total of 64 participants (32 patients with CLBP and 32 pain-free controls) were included in this study. The postural sway was measured under four conditions, sitting or standing on unstable surface, with eyes open or closed. The TDL parameters were compared between the two groups to explore their discriminative ability. The CLBP group had more body sway than the control group, characterized by several TDL parameters in sitting with eyes closed and standing with eyes open. The TDL parameters with the highest area under the curve according to the receiver operating characteristic curve analysis were the root mean square distance and mean frequency in the medial-lateral direction obtained in the sitting with eyes closed. In conclusion, we confirmed the advantage of using sitting posturographic parameters as a sensitive measure to detect impaired trunk control in patients with CLBP. The results would help choose sensitive outcome measures to reflect the postural control of patients with LBP.

Dry needling of the flexor digitorum brevis muscle reduces postural control in standing: A pre-post stabilometric study

There are studies that show the better balance after dry needling in lumbar pain. However, the postural control effects after foot dry needling are unknown. Our objective was to check if dry needling reduces postural control. Eighteen subjects with flexor digitorum brevis (FDB) muscle Myofascial trigger point were evaluated pre- and post-deep dry needling. We measured stabilometric variables in a pre-post study. We have found significant differences in three stabilometric variables: surface with eyes closed (29.36-53.21 mm2 ) (p = 0.000), medium speed of the laterolateral displacement with eyes closed (1.42-1.64 mm/s) (p = 0.004), and medium speed of the anteroposterior displacement with eyes closed (1.30-1.53 mm/s) (p = 0.025). Dry needling therapy application in FDB muscle reduces standing postural control with eyes closed.

Effectiveness of Pilates exercise on low back pain: a systematic review with meta-analysis

PURPOSE

Low back pain is the most frequently reported musculoskeletal disorder and represents one of the highest patient burdens in healthcare. This systematic review and meta-analysis aimed to investigate the effectiveness of Pilates exercise on pain intensity and functional disability caused by low back pain (LBP).

MATERIALS AND METHODS

A Systematic review with meta-analysis was conducted. Data sources: MEDLINE-NLM and MEDLINE-EBSCO. We also searched on Scopus Elsevier, Cochrane, DOAJ, SciELO, PEDro, and PLOS ONE databases. Eligibility criteria: randomized controlled trials (RCTs) evaluating LBP in which the primary treatment was based on Pilates exercise compared with no exercise, or non-specific exercise.

RESULTS

The search returned 1566 records of which 36 articles were included in the systematic review and 19 in the meta-analysis. Twenty-two studies compared the effects of Pilates exercise vs no exercise and 13 studies examined the effects of Pilates exercise vs non-specific exercise. Analysis showed that Pilates had a positive effect on the perception of LBP vs no exercise. A similar trend occurred with non-specific exercise.

CONCLUSIONS

Pilates exercise can decrease LBP compared to no exercise and non-specific exercise. General practitioners should consider Pilates exercise as an effective strategy to manage LBP and counteract the growing health.

TRIAL REGISTRATION

PROSPERO registration number: CRD42022308387.IMPLICATIONS FOR REHABILITATIONPilates is a good strategy for improving low back pain and is more effective than other exercise programs or no exercise.Pilates is a safe tool to apply to most of the population with low back pain.Pilates is a non-pharmacological strategy useful for counteracting low back pain.

The Role of Back Muscle Dysfunctions in Chronic Low Back Pain: State-of-the-Art and Clinical Implications

Changes in back muscle function and structure are highly prevalent in patients with chronic low back pain (CLBP). Since large heterogeneity in clinical presentation and back muscle dysfunctions exists within this population, the potential role of back muscle dysfunctions in the persistence of low back pain differs between individuals. Consequently, interventions should be tailored to the individual patient and be based on a thorough clinical examination taking into account the multidimensional nature of CLBP. Considering the complexity of this process, we will provide a state-of-the-art update on back muscle dysfunctions in patients with CLBP and their implications for treatment. To this end, we will first give an overview of (1) dysfunctions in back muscle structure and function, (2) the potential of exercise therapy to address these dysfunctions, and (3) the relationship between changes in back muscle dysfunctions and clinical parameters. In a second part, we will describe a framework for an individualised approach for back muscle training in patients with CLBP.

Biological Responses to Local Vibratory Stimulation for the Lower Legs and Lower Back and Criterion Values Based on Sweep Frequencies of Healthy Individuals: An Observational Study

Declining proprioceptive function is associated with problems such as lower back pain and falls. Therefore, we developed a vibration device using sweep frequency to evaluate several proprioceptors with different response frequency ranges. This study aimed to elucidate the biological responses of healthy individuals to vibratory stimulation at different sites and frequency ranges and to propose cutoff values to determine the decline in proprioceptive function. Mechanical vibration was separately applied to the lower legs and lower back, and proprioceptive function was evaluated by defining the ratio of the center of pressure (CoP) in the anteroposterior direction during mechanical vibration to that during no vibration in the three frequency ranges. The cut-off value was defined as the mean value, with the standard deviation subtracted for each indicator. The cut-off values were higher in the lower legs than in the lower back at all frequency ranges and in the 30-53 Hz and 56-100 Hz frequency ranges for both the lower legs and lower back. In healthy individuals, 9.9% and 8.6% were below the cut-off values in the 30-53 Hz and 56-100 Hz frequency ranges for the lower legs, respectively.

The effect of dual-task conditions on postural control in adults with low back pain: a systematic review and meta-analysis

BACKGROUND

Dual-task conditions, which involve performing two tasks simultaneously, may exacerbate pain and further impair daily functioning in individuals with low back pain (LBP). Understanding the effects of dual-task conditions on postural control in patients with LBP is crucial for the development of effective rehabilitation programs. Our objective was to investigate the impact of dual-task conditions on postural control in individuals with LBP compared to those without LBP.

METHODS

We conducted a comprehensive search of Medline via PubMed, Scopus, the Cochrane Central Register of Controlled Trials, Web of Science, and EMBASE databases, with no language restrictions, from inception to January 1, 2023. The primary outcome measures of the study were velocity, area, amplitude, phase plane portrait, and path/sway length of the center of pressure (CoP). Standardized mean difference (SMD) effect sizes were calculated, and the quality of the studies was assessed using the Newcastle-Ottawa Scale (NOS).

RESULTS

From 196 studies, five involving 242 adults (≥ 18 years) met the inclusion criteria. Three studies were rated as high quality, while two were deemed moderate. In the included studies, 140 participants had non-specific LBP, while 102 participants did not report any symptoms, with mean ages of 36.68 (± 14.21) and 36.35 (± 15.39) years, respectively. Three studies had both genders, one exclusively included females, and one did not specify gender. Meta-analyses of primary outcomes revealed no significant differences in postural control between patients with LBP and pain-free controls during both easy and difficult postural tasks and cognitive load for velocity (easy: SMD - 0.09, 95% CI - 0.91 to 0.74; difficult: SMD 0.12, 95% CI - 0.67 to 0.91), area (easy: SMD 0.82, 95% CI - 2.99 to 4.62; difficult: SMD 0.14, 95% CI - 2.62 to 2.89), phase plane (easy: SMD - 0.59, 95% CI - 1.19 to 0.02; difficult: SMD - 0.18, 95% CI - 0.77 to 0.42), path/sway length (easy: SMD - 0.18, 95% CI - 0.77 to 0.42; difficult: SMD - 0.14, 95% CI - 0.84 to 0.55), and amplitude (easy: SMD 0.89, 95% CI - 1.62 to 3.39; difficult: SMD 1.31, 95% CI - 1.48 to 4.10).

CONCLUSIONS

The current evidence suggests that there are no significant differences in postural control parameters during dual-task conditions between individuals with non-specific LBP and pain-free subjects. However, due to the limited number of available studies, significant publication bias, and considerable statistical heterogeneity, definitive conclusions cannot be drawn. Therefore, further research comprising high-quality studies with larger sample sizes is necessary to obtain conclusive results. Trial registration PROSPERO CRD42022359263.

Acute exercise as active inference in chronic musculoskeletal pain, effects on gait kinematics and muscular activity in patients and healthy participants: a study protocol for a randomised controlled laboratory trial

INTRODUCTION

Chronic musculoskeletal pain is a highly prevalent, complex and distressing condition that may negatively affect all domains of life. In view of an active inference framework, and resting on the concept of allostasis, human movement per se becomes a prerequisite for health and well-being while chronic pain becomes a sign of a system unable to attenuate an allostatic load. Previous studies on different subgroups of chronic pain conditions have demonstrated alterations in gait kinematics and muscle activity, indicating shared disturbances in the motor system from long-term allostatic load. We hypothesise that such alterations exist in heterogenous populations with chronic musculoskeletal pain, and that exposure to acute and controlled exercise may attenuate these alterations. Therefore, the main aim of this study is to investigate the acute effects of exercise on gait kinematics and activity of the back and neck muscles during diverse walking conditions in patients with chronic musculoskeletal pain compared with a reference sample consisting of healthy participants.

METHODS AND ANALYSIS

This two-sample two-armed parallel randomised controlled laboratory trial will include 40 participants with chronic musculoskeletal pain (>3 months) and 40 healthy participants. Participants will be randomly allocated to either 30 min of aerobic exercise or rest. Primary outcomes are gait kinematics (walking speed, step frequency, stride length, lumbar rotation, gait stability) and muscular activity (spatial and temporal) of the back and neck during diverse walking conditions. Secondary outcomes are variability of gait kinematics and muscle activity and subjective pain ratings assessed regularly during the trial.

ETHICS AND DISSEMINATION

The study has been approved by the Regional Ethics Review Board in Uppsala, Sweden (#2018/307). Findings will be disseminated via conference presentations, publications in peer-reviewed journals and engagement with patient support groups and clinicians.

TRIAL REGISTRATION NUMBER

NCT03882333.

The effects of proprioceptive weighting changes on posture control in patients with chronic low back pain: a cross-sectional study

Introduction

Patients with chronic low back pain (CLBP) exhibit changes in proprioceptive weighting and impaired postural control. This study aimed to investigate proprioceptive weighting changes in patients with CLBP and their influence on posture control.

Methods

Sixteen patients with CLBP and 16 healthy controls were recruited. All participants completed the joint reposition test sense (JRS) and threshold to detect passive motion test (TTDPM). The absolute errors (AE) of the reposition and perception angles were recorded. Proprioceptive postural control was tested by applying vibrations to the triceps surae or lumbar paravertebral muscles while standing on a stable or unstable force plate. Sway length and sway velocity along the anteroposterior (AP) and mediolateral (ML) directions were assessed. Relative proprioceptive weighting (RPW) was used to evaluate the proprioception reweighting ability. Higher values indicated increased reliance on calf proprioception.

Results

There was no significant difference in age, gender, and BMI between subjects with and without CLBP. The AE and motion perception angle in the CLBP group were significantly higher than those in the control group (JRS of 15°: 2.50 (2.50) vs. 1.50 (1.42), JRS of 35°: 3.83 (3.75) vs. 1.67 (2.00), p_JRS < 0.01; 1.92 (1.18) vs. 0.68 (0.52), p_TTDPM < 0.001). The CLBP group demonstrated a significantly higher RPW value than the healthy controls on an unstable surface (0.58 ± 0.21 vs. 0.41 ± 0.26, p < 0.05). Under the condition of triceps surae vibration, the sway length (p_stable < 0.05; p_unstable < 0.001), AP velocity (p_stable < 0.01; p_unstable < 0.001) and ML velocity (p_unstable < 0.05) had significant group main effects. Moreover, when the triceps surae vibrated under the unstable surface, the differences during vibration and post vibration in sway length and AP velocity between the groups were significantly higher in the CLBP group than in the healthy group (p < 0.05). However, under the condition of lumbar paravertebral muscle vibration, no significant group main effect was observed.

Conclusion

The patients with CLBP exhibited impaired dynamic postural control in response to disturbances, potentially linked to changes in proprioceptive weighting.

The effect of chronic low back pain on postural control during quiet standing: A meta-analysis

Low back pain (LBP) has been associated with altered body sway during quiet standing, but the pattern of results is inconsistent. The purpose of this meta-analysis is to examine the effects of vision (eyes open, eyes closed) and changing the support surface (foam surface, firm surface) on postural sway during quiet standing in individuals with chronic LBP (cLBP). Five electronic databases were searched on March 27th, 2022. Of 2,856, 16 studies (n = 663) were included. Across all conditions, we found a positive and medium effect size (g = 0.77 [0.50, 1.04]) that represented greater body sway in individuals with cLBP. Subgroup analyses revealed medium effects during eyes open conditions (firm surface: g = 0.60 [0.33, 0.87]; foam surface: g = 0.68 [0.38, 0.97]), and large effects during eyes closed conditions (firm surface: g = 0.97 [0.60, 1.35]; foam surface: g = 0.89 [0.28, 1.51]). We quantified effects of self-reported pain and found a moderate effect during eyes closed plus firm surface conditions (Q = 3.28; p = 0.070). We conclude that cLBP is associated with increased postural sway, with largest effect sizes evident when vision is removed and when self-reported pain intensity is higher.

Effects of non-extensible lumbar belts on static and dynamic postural stability

BACKGROUND

Previous studies have found that increased intra-abdominal pressure helps to reduce spinal loading and improve spine stability. Non-extensible lumbar belts (NEBs) could elevate intra-abdominal pressure and augment spinal stability. NEBs have been used in the healthcare field to help reduce pain and improve spine function for people with low back pain. However, the effect of NEBs on static and dynamic postural stability is not clear.

METHODS

This study aimed to investigate whether NEBs affect static and dynamic postural stability. Twenty-eight healthy male subjects were recruited to finish four static postural stability tasks and two dynamic postural stability tests. Center of pressure (COP) values during 30 s of quiet standing, dynamic postural stability index (DPSI) and Y balance test (YBT) score with and without NEBs were analyzed.

RESULTS

NEBs had no significant effect in all COP variables in the static postural tasks. The results of a repeated measure two-way ANOVA indicated the NEBs significantly improved the dynamic postural stability in YBT score and DPSI (F _(1,27) = 5.506, p = .027, [Formula: see text] and F _(1,27) = 83.94, p = .000, [Formula: see text] respectively).

CONCLUSIONS

The study results indicate that non-extensible belts improve dynamic stability in healthy male participants, with potential implications for rehabilitation and performance enhancement programs.

The immediate effects of iTBS on the muscle activation pattern under challenging balance conditions in the patients with chronic low back pain: A preliminary study

Background

The patients with chronic low back pain (CLBP) showed impaired postural control, especially in challenging postural task. The dorsolateral prefrontal cortex (DLPFC) is reported to involve in the complex balance task, which required considerable attentional control. The effect of intermittent theta burst stimulation (iTBS) over the DLPFC to the capacity of postural control of CLBP patients is still unknown.

Methods

Participants diagnosed with CLBP received a single-session iTBS over the left DLPFC. All the participants completed the postural control tasks of single-leg (left/right) standing before and after iTBS. The activation changes of the DLPFC and M1 before and after iTBS were recorded by functional near-infrared spectroscopy (fNIRS). The activation pattern of the trunk [transversus abdominis (TrA), superficial lumbar multifidus (SLM)] and leg [tibialis anterior (TA), gastrocnemius medialis (GM)] muscles including root mean square (RMS) and co-contraction index (CCI) during single-leg standing were measured by surface electromyography (sEMG) before and after the intervention. The paired t-test was used to test the difference before and after iTBS. Pearson correlation analyses were performed to test the relationship between the oxyhemoglobin concentration and sEMG outcome variables (RMS and CCI).

Results

Overall, 20 participants were recruited. In the right-leg standing condition, compared with before iTBS, the CCI of the right TrA/SLM was significantly decreased (t = −2.172, p = 0.043), and the RMS of the right GM was significantly increased (t = 4.024, p = 0.001) after iTBS. The activation of the left DLPFC (t = 2.783, p = 0.012) and left M1 (t = 2.752, p = 0.013) were significantly decreased and the relationship between the left DLPFC and M1 was significant after iTBS (r = 0.575, p = 0.014). Correlation analysis showed the hemoglobin concentration of M1 was negatively correlated with the RMS of the right GM (r = −0.659, p = 0.03) and positively correlated between CCI of the right TrA/SLM (r = 0.503, p = 0.047) after iTBS. There was no significant difference in the brain or muscle activation change in the left leg-standing condition between before and after iTBS.

Conclusion

Intermittent theta burst stimulation over the left DLPFC seems to be able to improve the muscle activation pattern during postural control ability in challenging postural task, which would provide a new approach to the treatment of CLBP.

Effect of external lumbar supports on joint position sense, postural control, and postural adjustment: a systematic review

PURPOSE

To review the effects of external lumbar supports on various aspects of sensorimotor function including joint position sense (JPS), postural control, anticipatory postural adjustments (APAs), and compensatory postural adjustments (CPAs).

METHODS

A systematic literature search was performed in PubMed, EMBASE, Scopus, Ovid, Cochrane library, and Web of Science. Two reviewers selected studies which assessed the effect of lumbosacral orthosis or kinesio-tape on JPS, postural control or APAs/CPAs in subjects with and without low back pain (LBP). The methodological quality of included studies was assessed using a modified version of Downs and Black's checklist.

RESULTS

Findings demonstrated moderate effects of lumbosacral orthosis on specific aspects of sensorimotor control including JPS and to a lesser extent standing stability. These domains were not or minimally affected by application of kinesio-tape. Both orthosis and kinesio-tape had negligible effects on APAs and CPAs.

CONCLUSIONS

The positive effects of lumbar orthosis on JPS or postural control were mostly observed in conditions where sources of proprioceptive feedback are impaired (such as LBP) or absent (standing with eyes closed on an unstable surface). However, evidence does not prove significant positive effects for the application of kinesio-tape to improve sensorimotor control.IMPLICATIONS FOR REHABILITATIONWearing lumbar orthosis leads to an improvement in joint position sense.Postural stability seems to be affected to some extent by utilizing lumbar orthosis.Clinicians can administer orthosis to improve sensorimotor adaptation, especially in conditions with poor proprioception.Kinesio-tape had negligible effects on all domains of sensorimotor control.Improvement of sensorimotor function as a result of application of kinesio-tape is questionable.

The dynamic postural steadiness and stabilization time between older adults with and without recurrent low back pain

BACKGROUND

Although postural control measures were reported to identify neuromuscular impairments, postural steadiness and stabilization time were not carefully investigated between subjects with and without recurrent low back pain (LBP). Research QuestionAre there group differences in the stabilization time, direction of sway, and dynamic postural steadiness index (DPSI) during one-leg standing?

METHODS

Thirty-four control subjects and 29 subjects with recurrent LBP participated in the study. Each subject stood upright on a single leg with and without visual input. The outcomes were measured for standing duration (sec), direction of sway, and the DPSI, which included the vertical steadiness index (VSI). The VSI assesses fluctuations to standardize the vertical ground reaction forces on the force plate.

RESULTS

The control group demonstrated significantly longer standing duration compared to the LBP group during the eyes-open condition (t = 3.55, p = 0.001). The LBP group demonstrated significantly faster stabilization time (t = 2.53, p = 0.01) in the sagittal plane. The DPSI demonstrated an excellent relationship with the VSI without visual input in the control group (r = 0.98, p = 0.001). The directions of sway demonstrated a significant interaction between groups (F = 9.29, p = 0.004).

SIGNIFICANCE

Although standing duration in the eyes-open condition decreased in the LBP group, a faster stabilization time in the sagittal plane was evident compared to the control group to adapt postural stability. These results indicated that vertical dynamic steadiness with visual input might be important to enhance compensatory postural control.

Distinction of non-specific low back pain patients with proprioceptive disorders from healthy individuals by linear discriminant analysis

The central nervous system (CNS) dynamically employs a sophisticated weighting strategy of sensory input, including vision, vestibular and proprioception signals, towards attaining optimal postural control during different conditions. Non-specific low back pain (NSLBP) patients frequently demonstrate postural control deficiencies which are generally attributed to challenges in proprioceptive reweighting, where they often rely on an ankle strategy regardless of postural conditions. Such impairment could lead to potential loss of balance, increased risk of falling, and Low back pain recurrence. In this study, linear and non-linear indicators were extracted from center-of-pressure (COP) and trunk sagittal angle data based on 4 conditions of vibration positioning (vibration on the back, ankle, none or both), 2 surface conditions (foam or rigid), and 2 different groups (healthy and non-specific low back pain patients). Linear discriminant analysis (LDA) was performed on linear and non-linear indicators to identify the best sensory condition towards accurate distinction of non-specific low back pain patients from healthy controls. Two indicators: Phase Plane Portrait ML and Entropy ML with foam surface condition and both ankle and back vibration on, were able to completely differentiate the non-specific low back pain groups. The proposed methodology can help clinicians quantitatively assess the sensory status of non-specific low back pain patients at the initial phase of diagnosis and throughout treatment. Although the results demonstrated the potential effectiveness of our approach in Low back pain patient distinction, a larger and more diverse population is required for comprehensive validation.

Five Times Sit-to-Stand Test in people with non-specific chronic low back pain—a cross-sectional test–retest reliability study

PURPOSE/AIM

The Five Times Sit-to-Stand Test (FTSST) is a method that evaluates lower extremity muscle strength and balance level. The aim of this study is to test the validity and reliability of the FTSST in patients with non-specific chronic low back pain (NSCLBP) whose lower extremity muscle strength and balance levels are adversely affected.

METHODS

The first outcome measure of the study was the FTSST, which was conducted by two different researchers. Secondary outcome measures are Biodex Balance System (BBS), Quadriceps Muscle Strength Test, Oswestry Disability Index (ODI), and Visual Analogue Scale (VAS). Intraclass Correlation Coefficient (ICC) was used for the validity and reliability of the FTSST, which was made by two different researchers, and Pearson's Correlation Analysis was used to determine its relationship with other measurements.

RESULTS

Inter-rater and test-retest reliability for the FTSST were excellent (Intraclass Correlation Coefficient = 0.99). A statistically significant correlation was found between all secondary outcome measures (BBS, quadriceps muscle strength, ODI, VAS) and FTSST (p < 0.05).

CONCLUSION

In line with the findings of our study, we think that FTSST is a simple, easy, and reproducible method for evaluating lower extremity muscle strength, balance level, functional status, and pain in patients with NSCLBP.

Does Improvement towards a Normal Cervical Sagittal Configuration Aid in the Management of Lumbosacral Radiculopathy: A Randomized Controlled Trial

A randomized controlled study with a six-month follow-up was conducted to investigate the effects of sagittal head posture correction on 3D spinal posture parameters, back and leg pain, disability, and S1 nerve root function in patients with chronic discogenic lumbosacral radiculopathy (CDLR). Participants included 80 (35 female) patients between 40 and 55 years experiencing CDLR with a definite hypolordotic cervical spine and forward head posture (FHP) and were randomly assigned a comparative treatment control group and a study group. Both groups received TENS therapy and hot packs, additionally, the study group received the Denneroll cervical traction orthotic. Interventions were applied at a frequency of 3 x per week for 10 weeks and groups were followed for an additional 6-months. Radiographic measures included cervical lordosis (CL) from C2–C7 and FHP; postural measurements included: lumbar lordosis, thoracic kyphosis, trunk inclination, lateral deviation, trunk imbalance, surface rotation, and pelvic inclination. Leg and back pain scores, Oswestry Disability Index (ODI), and H-reflex latency and amplitude were measured. Statistically significant differences between the groups at 10 weeks were found: for all postural measures, CL (p = 0.001), AHT (p = 0.002), H-reflex amplitude (p = 0.007) and latency (p = 0.001). No significant difference for back pain (p = 0.2), leg pain (p = 0.1) and ODI (p = 0.6) at 10 weeks were identified. Only the study group’s improvements were maintained at the 6-month follow up while the control groups values regressed back to baseline. At the 6-month follow-up, it was identified in the study group that improved cervical lordosis and reduction of FHP were found to have a positive impact on 3D posture parameters, leg and back pain scores, ODI, and H-reflex latency and amplitude.

Immediate Effect of Lumbosacral Orthosis and Abdominal Drawing-In Maneuver on Postural Control in Adults With Nonspecific Chronic Low Back Pain

OBJECTIVE

The purpose of this study was to examine the immediate effects of lumbosacral orthosis and the abdominal drawing-in maneuver on the trunk postural control of adults with chronic low back pain compared with asymptomatic controls during 1-legged and semi-tandem stances.

METHODS

An experimental and comparative study (cross-sectional design) was conducted in a laboratory setting. Twenty adults with chronic low back pain and 20 asymptomatic controls randomly performed 2 postural balance tasks over a force platform, considering 3 experimental conditions: (1) natural posture (baseline-control), (2) lumbosacral orthosis, and (3) abdominal drawing-in maneuver. Linear variables (mean amplitude, ellipse area, and sway velocity) derived from the center of pressure were computed, and 2-way analysis of variance (group × condition) for repeated measures were conducted.

RESULTS

No group × condition interactions (.139 ≤ P ≤.938) were detected in any center of pressure parameters. No condition effect was detected, but a group effect (P = .042) was observed for 1 center of pressure parameter. The chronic low back pain group presented with a lower mean anteroposterior center of pressure amplitude than asymptomatic controls (∆ = 0.31 ± 0.66 cm [95% confidence interval, 0.05-0.56], P = .019) during the semi-tandem stance balance task.

CONCLUSION

Neither lumbosacral orthosis nor the abdominal drawing-in maneuver showed immediate improvement in trunk postural control in any group. Thus, clinicians should not expect immediate benefits or improvements yielded by lumbosacral orthosis or the abdominal drawing-in maneuver when patients with chronic low back pain undergo these interventions.

Evaluation of the durable effects of corrective exercises on the postural alignment and stability in hyperkyphotic elderly with a history of falls

Background

This study aimed to investigate the durability of the effects of corrective exercises on the postural alignment and stability of hyperkyphotic elderly with a history of falls. Balance disturbance and recurrent falls are directly related to changes in the alignment of physical posture and function of the elderly, and effective methods with durable effects on improving the postural stability of the elderly have always been under the attention of researchers.

Methods

This study was a randomized clinical trial, and the statistical population included the elderly referred to neurology clinics. According to the research inclusion criteria (hyperkyphotic elderly with a history of falls during the last six months), 30 elderly aged 60 to 75 years old were purposefully selected and randomly divided into two groups of corrective exercises and control. The experimental group performed an exercise program based on the Alexander posture correction technique. Both groups were evaluated with forward head angle, kyphosis, the timed up and go test, postural stability, and fear of falling tests in three phases. Data analysis was conducted using SPSS 21 software and the MANCOVA test and repeated-measures analysis of variance.

Results

Data analysis showed significant improvements in the variables of forward head (p = 0.007), kyphosis(p = .001), balance(p = 0.002), postural stability(p = 0.001), and fear of falling(p = 0.001) in the experimental group. Post-test comparisons between the experimental and control groups showed significant differences in all variables except for kyphosis(p > .05), and follow-up analysis also revealed significant differences in all variables, except for the variables of forward head and kyphosis(p > .05).

Conclusions

Although the effects of corrective exercises in the elderly decreased regarding spinal alignment after three months, more lasting effects were seen in functional balance, postural stability, and fear of falling, suggesting this strategy as a stimulus for more mobility and a lower risk of falling in the elderly. Therefore, when using corrective exercises, it is possible to apply these exercises for a longer period of time to achieve more durable outcomes, especially regarding spinal alignment.

Trial registration

This research was registered in the Iranian Registry of Clinical Trials (IRCT2016081529373N1, Date of registration: 19/04/2017).

A Comprehensive Review of Pain Interference on Postural Control: From Experimental to Chronic Pain

Motor control, movement impairment, and postural control recovery targeted in rehabilitation could be affected by pain. The main objective of this comprehensive review is to provide a synthesis of the effect of experimental and chronic pain on postural control throughout the available literature. After presenting the neurophysiological pathways of pain, we demonstrated that pain, preferentially localized in the lower back or in the leg induced postural control alteration. Although proprioceptive and cortical excitability seem modified with pain, spinal modulation assessment might provide a new understanding of the pain phenomenon related to postural control. The literature highlights that the motor control of trunk muscles in patient presenting with lower back pain could be dichotomized in two populations, where the first over-activates the trunk muscles, and the second under-activates the trunk muscles; both generate an increase in tissue loading. Taking all these findings into account will help clinician to provide adapted treatment for managing both pain and postural control.

The Function Assessment Scale for Spinal Deformity: Validity and Reliability of a New Clinical Scale

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

The aim of this study was to develop and validate the Function Assessment scale for Spinal Deformity (FASD).

SUMMARY OF BACKGROUND DATA

Spinal malalignment impacts daily functioning. Standard evaluation of adult spinal deformity (ASD) is based on static radiography and patient-reported scores, which fail to assess functional impairments. A clinical scale, quantifying function and balance of patients with ASD, could increase our insights on the impact of ASD on functioning.

METHODS

To develop the FASD, 70 ASD patients and 20 controls were measured to identify the most discriminating items of the Balance Evaluation Systems Test and Trunk Control Measurement Scale. Discussions between experts on the clinical relevance of selected items led to further item reduction. The FASD's discriminative ability was established between 43 patients and 19 controls, as well as between three deformity subgroups. For its responsiveness to treatment, 10 patients were reevaluated 6 months postoperatively. Concurrent validity was assessed through correlation analysis with radiographic parameters (pelvic tilt; sagittal vertical axis [SVA]; pelvic incidence minus lumbar lordosis [PI-LL]; coronal vertical axis) and patient-reported scores [Oswestry Disability Index]; Scoliosis Research Society outcome questionnaire; Falls Efficacy Scale-International). Test-retest and interrater reliability were tested on two groups of ten patients using intraclass correlation coefficients (ICC).

RESULTS

Patients with ASD, mainly with sagittal malalignment, scored worse compared to controls on FASD (P < 0.001) and its subscales. No significant improvement was observed 6 months postoperatively (P = 0.758). FASD correlated significantly to all patient-reported scores and to SVA and PI-LL. Reliability between sessions (ICC = 0.97) and raters (ICC = 0.93) was excellent. Subscales also showed good to excellent reliability, except FASD 1 on "spinal mobility and balance" between sessions (ICC = 0.71).

CONCLUSION

FASD proved to be a valid and reliable clinical scale for evaluation of functional impairments in ASD. Objective information on function and balance might ultimately guide physiotherapeutic treatment toward improved functioning.Level of Evidence: 2.

Proprioceptive postural control strategies differ among non-injured athletes

Postural control during complex tasks requires adequate sensory integration and somaesthetic reweighting: suboptimal postural strategies can lead to injury. We assessed the ability of healthy athletes to reweight somaesthetic signals during postural perturbations on different surfaces. Thirty-five young (16 ± 1 years), healthy, elite handball players participated in this cross-sectional study. Proprioceptive reweighting was evaluated via vibration of the triceps surae and lumbar muscles on firm and foam surfaces. Postural variables and the electromyographic activity of the gluteus medius (GM), semitendinosus (ST) and fibularis longus (FL) were recorded during the PRE (10 s), VIBRATION (20 s) and POST (20 s) periods. Ankle proprioception was predominantly used on the firm compared to foam support. However, two opposing behaviours were observed: a "rigid" strategy in which reliance on ankle proprioception increased on the foam, and a "plastic" strategy that involved a proximal shift of proprioceptive reliance (p < 0.001). The plastic strategy was associated with a more effective recovery of balance after vibration cessation (p < 0.05). ST activation was higher during POST in the rigid strategy and did not return to the PRE level (p < 0.05) whereas it did in the plastic strategy. Proprioceptive strategies for postural control are highly variable and future studies should evaluate their contribution to injury.

Preferred Limb Reaction, Swing and Recovery Step Times between Subjects with and without Chronic Low Back Pain

A compensatory stepping strategy following repeated perturbations may compromise dynamic balance and postural stability. However, there is a lack of study on preferred limb reaction, swing, and step time adjustments. The purpose of this study was to investigate limb reaction, swing, and recovery step times following repeated trip perturbations in individuals with and without non-specific chronic low back pain (LBP). There were 30 subjects with LBP and 50 control subjects who participated in the study. The limb reaction, swing, and recovery step times (s) were measured following treadmill-induced random repeated perturbations (0.12 m/s velocity for 62.5 cm displacement), which caused subjects to move forward for 4.90 s. Both groups demonstrated a significant interaction of repetitions and times (F = 4.39, p = 0.03). Specifically, the recovery step time was significantly shorter in the LBP group during the first trip (t = 2.23, p = 0.03). There was a significant interaction on repetitions and times (F = 6.03, p = 0.02) in the LBP group, and the times were significantly different (F = 45.04, p = 0.001). The initial limb reaction time of the LBP group was significantly correlated with three repeated swing times to avoid falls. The novelty of the first trip tends to enhance a protective strategy implemented by the LBP group. Although limb preference did not demonstrate a significant difference between groups, the LBP group demonstrated shorter recovery step times on their preferred limb initially in order to implement an adaptive strategy to avoid fall injuries following repeated perturbations.

Does piriformis muscle syndrome impair postural balance? A case control study

BACKGROUND AND PURPOSE

While patients with musculoskeletal disorders reported postural balance impairments, it is unknown whether patients with piriformis muscle syndrome (PMS) may exhibit postural balance disorders compared to controls. The aim was to compare postural balance in patients with PMS to controls in static and dynamic conditions.

MATERIAL AND METHODS

Twelve patients with PMS and twelve controls were enrolled. Static postural balance was assessed by calculating the symmetry index (SI) in the unipedal posture. To measure vision contribution, the Romberg index (RI) was computed. Dynamic postural balance was evaluated with the Timed up and go test (TUGT). Besides, inter-limb strength asymmetry (SA), pain and the short form-36 (SF-36) were assessed.

RESULTS

The PMS group (PMSG) exhibited significant (p < 0.001) higher SI in eyes opened (EO) and eyes closed (EC) conditions compared to the control group (CG). Besides, PMSG had significant higher RI (p < 0.05), TUGT scores (p < 0.001), SA values (p < 0.05), pain intensity (p < 0.001), and worse SF-36 scores on all physical health (p < 0.05) and psychological health (only in vitality and mental health [p < 0.05]), compared to CG.

CONCLUSION

Our data revealed impaired static and dynamic postural balance, and reduced quality of life in PMSG compared to CG. Postural balance impairments could explain the poor quality of life, which are likely due to the higher SA and higher pain intensity. Clinicians and physiotherapists should consider postural balance disorders while designing rehabilitation programs in these patients.

The association of reactive balance control and spinal curvature under lumbar muscle fatigue

Background

Although low back fatigue is an important intervening factor for physical functioning among sedentary people, little is known about its possible significance in relation to the spinal posture and compensatory postural responses to unpredictable stimuli. This study investigates the effect of lumbar muscle fatigue on spinal curvature and reactive balance control in response to externally induced perturbations.

Methods

A group of 38 young sedentary individuals underwent a perturbation-based balance test by applying a 2 kg load release. Sagittal spinal curvature and pelvic tilt was measured in both a normal and Matthiass standing posture both with and without a hand-held 2 kg load, and before and after the Sørensen fatigue test.

Results

Both the peak anterior and peak posterior center of pressure (CoP) displacements and the corresponding time to peak anterior and peak posterior CoP displacements significantly increased after the Sørensen fatigue test (all at p < 0.001). A lumbar muscle fatigue led to a decrease of the lumbar lordosis in the Matthiass posture while holding a 2 kg load in front of the body when compared to pre-fatigue conditions both without a load (p = 0.011, d = 0.35) and with a 2 kg load (p = 0.000, d = 0.51). Also the sacral inclination in the Matthiass posture with a 2 kg additional load significantly decreased under fatigue when compared to all postures in pre-fatigue conditions (p = 0.01, d = 0.48). Contrary to pre-fatigue conditions, variables of the perturbation-based balance test were closely associated with those of lumbar curvature while standing in the Matthiass posture with a 2 kg additional load after the Sørensen fatigue test (r values in range from −0.520 to −0.631, all at p < 0.05).

Conclusion

These findings indicate that lumbar muscle fatigue causes changes in the lumbar spinal curvature and this is functionally relevant in explaining the impaired ability to maintain balance after externally induced perturbations. This emphasizes the importance for assessing both spinal posture and reactive balance control under fatigue in order to reveal their interrelations in young sedentary adults and predict any significant deterioration in later years.

The Effect of Virtual Reality Training on Anticipatory Postural Adjustments in Patients with Chronic Nonspecific Low Back Pain: A Preliminary Study

Objectives

This study is aimed at exploring the effects of virtual reality (VR) training on postural control, measured by anticipatory and compensatory postural adjustments (APAs and CPAs, respectively), in patients with chronic nonspecific low back pain (CNLBP) and the potential neuromuscular mechanism of VR training.

Methods

Thirty-four patients were recruited and randomly assigned to the VR group (n = 11), the motor control exercise group (MCE, n = 12) and the control group (CG, n = 11). The VR group received VR training using Kinect Xbox 360 systems and magnetic therapy. Besides magnetic therapy, the participants in the MCE group performed real-time ultrasound-guided abdominal drawing-in maneuver (ADIM) and four-point kneeling exercise. The CG only received magnetic therapy. Surface muscle electromyography (sEMG) was used to record the muscle activities of transverse abdominis (TrA), multifidus (MF), lateral gastrocnemius (LG), and tibialis anterior (TA) during ball-hitting tasks. The muscle activation time and integrals of the electromyography activities (IEMGs) during the APA and CPA stages were calculated and used in the data analysis. The visual analogue scale (VAS) and Oswestry dysfunction index (ODI) scores were also recorded.

Results

A significant interaction effect of time × group was observed on the activation time of TrA (p = 0.018) and MF (p = 0.037). The post-intervention activation time of the TrA was earlier in the VR group (p = 0.029). In contrast, the post-intervention activation time of the MF was significantly delayed in the VR group (p = 0.001). The IEMGs of TrA (p = 0.002) and TA (p = 0.007) during CPA1 significantly decreased only in the VR group after the intervention. The VAS scores of three group participants showed significant decreases after intervention (p < 0.001).

Conclusions

Patients with CNLBP showed reciprocal muscle activation patterns of the TrA and MF muscles after VR training. VR training may be a potential intervention for enhancing the APAs of the patients with CNLBP.

The effects of dry needling on pain relief and functional balance in patients with sub-chronic low back pain

BACKGROUND

Pain relief is important both for the movement of patients suffering from low back pain and the quality of life. Dry needling is effective on myofascial trigger points but its effect on the area of pain and the functional balance is not fully known.

OBJECTIVE

To examine the immediate effect of dry needling on pain and functional balance of patients suffering from low back pain.

METHODS

Twenty five patients with sub-chronic low back pain were randomly divided into two groups: the intervention or control group. Needles were used for the participants of the intervention group, bilaterally at the spinus level, one and a half finger breath from the midline in levels L2-L5 of the lumbar spine. A third line of needles was inserted in the interspinosus spaces, except L5-S1 level. Bipedal stance, lateral loading and mediolateral body sway were assessed using a pair of force plates. Pain tolerance was assessed using an algometer.

RESULTS

The pain tolerance significantly increased in the intervention group from (M = 4.87, SE 0.663) to (M = 6.52, SE 0.547) (F(1,23) = 7.8, p< 0.05) after intervention. During mediolateral body sway the force signal in the dominant frequency significantly increased in the intervention group from (M = 43.2, SE 4.6) to (M = 54,9, SE 3.6) (F(1,23) = 4.63, p< 0.05) after intervention, exhibiting more controlled rhythmic behavior.

CONCLUSIONS

Dry needling in painful areas and penetrating all the muscle groups seems to improve pain and functional balance, yet its effect on specific muscles needs to be studied further.

Effects of back extensor and hip abductor fatigue on dynamic postural stability in patients with nonspecific chronic low back pain: A case-control study

INTRODUCTION

Patients with nonspecific chronic low back pain (NSCLBP) complain of pain and fatigue during functional activities. Poor back muscle endurance has been associated with recurrent pain and long-term disability. However, the relationship between proximal muscle fatigue and postural stability is not well understood.

PURPOSE

To investigate the effects of lumbar extensor and hip abductor fatigue on postural stability in NSCLBPs.

METHODS

To induce isolated fatigue, participants (24 LBPs, 24 controls) were asked to perform multiple back extension and hip abduction in the separate sessions until the muscle force reached 60% of pre-fatigued force. The overall (OSI), anteroposterior (APSI), and mediolateral (MLSI) stability indices were measured during single-leg stance using the Biodex dynamic platform.

RESULTS

The results revealed higher postural instability (APSI and OSI) following fatiguing lumbar extensor and hip abductor muscles (greater effect size for APSI than OSI) in LBPs than controls. Furthermore, significant and inverse relationships were found between the level of physical activity, pain, and post-fatigue postural instability (OSI) in NSCLBPs.

CONCLUSION

Fatigue of proximal muscles could differentiate postural stability primarily in the sagittal plane between NSCLBPs and controls. Therefore, reducing the fatigability of these muscles by endurance training in addition to balance training may improve physical activity.

Understanding the impact of lumbar disc degeneration and chronic low back pain: A cross-sectional electromyographic analysis of postural strategy during predicted and unpredicted postural perturbations

People with chronic low back pain (LBP) exhibit changes in postural control. Stereotypical muscle activations resulting from external perturbations include anticipatory (APAs) and compensatory (CPAs) postural adjustments. The aim and objective of this study was to determine differences in postural control strategies (peak amplitude, APAs and CPAs) between symptomatic and asymptomatic adults with and without Lumbar Disc Degeneration (LDD) using surface electromyography during forward postural perturbation. Ninety-seven subjects participated in the study (mean age 50 years (SD 12)). 3T MRI was used to acquire T2 weighted images (L1-S1). LDD was determined using Pfirrmann grading. A bespoke translational platform was designed to deliver horizontal perturbations in sagittal and frontal planes. Electromyographic activity was analysed bilaterally from 8 trunk and lower limb muscles during four established APA and CPA epochs. A Kruskal-Wallis H test with Bonferroni correction for multiple comparisons was conducted. Four groups were identified: no LDD no pain (n = 19), LDD no pain (n = 38), LDD pain (n = 35) and no LDD pain (n = 5). There were no significant differences in age or gender between groups. The most significant difference between groups was observed during forward perturbation. In the APA and CPA phases of predictable forward perturbation there were significant differences ankle strategy between groups (p = 0.007–0.008); lateral gastrocnemius and tibialis anterior activity was higher in the LDD pain than the LDD no pain group. There were no significant differences in the unpredictable condition (p>0.05). These findings were different from the remaining groups, where significant differences in hip strategy were observed during both perturbation conditions (p = 0.004–0.006). Symptomatic LDD patients exhibit different electromyographic strategies to asymptomatic LDD controls. Future LBP electromyographic research should benefit from considering assessment of both lower limbs in addition to the spine. This approach could prevent underestimation of postural control deficits and guide targeted rehabilitation.

Comparison of the reliance of the postural control system on the visual, vestibular and proprioceptive inputs in chronic low back pain patients and asymptomatic participants

BACKGROUND

Although proprioception deficits have been documented in chronic low back pain (CLBP) patients, little is known about adaptive strategies to provide postural control in these patients. Substitution of unreliable proprioceptive information with other afferents might be considered plausible.

RESEARCH QUESTION

Is the response of the postural control system dependent on the source of sensory afferents being manipulated in persons with and without CLBP?

METHODS

Sixty persons with and without CLBP participated in this cross-sectional study. Center of pressure (COP) displacement range, velocity, path length and area were calculated under four sensory conditions: 1) normal upright standing; 2) upright standing on a foam with eyes open and head in neutral position; 3) upright standing with eyes open and 60° cervical extension and 4) upright standing with eyes closed and 60° cervical extension. A two-way repeated measures analysis of variance was used to compare COP masseurs under different conditions and between the groups.

RESULTS

CLBP patients demonstrated fewer alterations to manipulation of both visual and vestibular afferents in terms of number of COP variables significantly altered. ML range and velocity in both groups and path length in the CLBP group were significantly different between conditions 2 and 4. In both groups, all COP variables except AP range increased significantly in condition 2 compared to conditions 1and 3 (p < 0.001). AP velocity was the only variable to be different between conditions 1 and 3 in both CLBP (p = 0.025) and control (p < 0.001) groups. Between group differences were significant on AP velocity (p = 0.019).

SIGNIFICANCE

No overweighting was observed in the vestibular or visual afferents in CLBP patients. Compensatory strategies seem to lie within proprioceptive system by reweighting afferents from different body segments. The postural control system behaved more robustly in CLBP patients while AP COP velocity was found as the most sensitive and discriminating parameter.