The efficacy of plantar stimulation on human balance control

Impact of five floor coverings on the orthostatic balance of healthy subjects

Plantar skin sensitivity contributes to the regulation of postural control and, therefore, changing the characteristics of the plantar support surface can modify this control. This study aimed at assessing the impact of five different floor coverings on the orthostatic balance in 48 healthy subjects. Static posturography was performed with eyes open or closed on a platform in a control condition (no covering) and with five different covering surfaces: foam, silicone, ethyl vinyl acetate, and two textured mats with small (height 2 mm) or large pimples (7 mm). The average velocity of center of pressure (CoP) displacement was the primary endpoint measure and ten other posturographic variables were assessed. Comfort and pain produced by the covering were also scored. In eyes open condition, the average velocity of CoP displacement was increased when subjects stood on the foam mat, the silicone mat, and especially the textured mat with large pimples. Several other posturographic variables showed significant changes with different types of floor coverings with eyes open. These changes were not correlated to the comfort or pain scores associated with the different surfaces. In contrast, no difference was observed compared to the control condition (no covering) with eyes closed. This study shows that adding smooth or textured floor covering can alter balance in eyes open condition. In eyes closed condition, although more disturbing for balance, healthy subjects achieved better postural adaptation, probably by mobilizing more of their proprioceptive resources. This posturographic examination procedure could, therefore, be used to assess "proprioceptive reserve" capacities in clinical practice.

A Novel Neurorehabilitation Approach for Neural Plasticity Overstimulation and Reorganization in Patients with Neurological Disorders

Neurological disorders are those that are associated with impairments in the nervous system. These impairments affect the patient’s activities of daily living. Recently, many advanced modalities have been used in the rehabilitation field to treat various neurological impairments. However, many of these modalities are available only in clinics, and some are expensive. Most patients with neurological disorders have difficulty reaching clinics. This review was designed to establish a new neurorehabilitation approach based on the scientific way to improve patients’ functional recovery following neurological disorders in clinics or at home. The human brain is a network, an intricate, integrated system that coordinates operations among billions of units. In fact, grey matter contains most of the neuronal cell bodies. It includes the brain and the spinal cord areas involved in muscle control, sensory perception, memory, emotions, decision-making, and self-control. Consequently, patients’ functional ability results from complex interactions among various brain and spinal cord areas and neuromuscular systems. While white matter fibers connect numerous brain areas, stimulating or improving non-motor symptoms, such as motivation, cognitive, and sensory symptoms besides motor symptoms may enhance functional recovery in patients with neurological disorders. The basic principles of the current treatment approach are established based on brain connectivity. Using motor, sensory, motivation, and cognitive (MSMC) interventions during rehabilitation may promote neural plasticity and maximize functional recovery in patients with neurological disorders. Experimental studies are strongly needed to verify our theories and hypothesis.

Effectiveness of Somatosensory Stimulation for the Lower Limb and Foot to Improve Balance and Gait after Stroke: A Systematic Review

This systematic review’s purpose was to evaluate the effectiveness of lower-limb and foot somatosensory stimulation to improve balance and gait post-stroke. PRISMA reporting guidelines were followed. Included studies: randomized controlled trials (RCTs), published in English with ethical approval statement. Studies of conditions other than stroke, functional electrical stimulation, and interventions eliciting muscle contraction, were excluded. AgeLine, AMED, CINAHL PLUS, EMBASE, EMCARE MEDLINE, PEDro, PsycARTICLES, PsycINFO, SPORTDiscus, Web of Science and Cochrane central register of controlled trials were searched from 1 January 2002 to 31 March 2022. Two authors independently screened results, extracted data and assessed study quality using Cochrane Risk of Bias 2 tool; 16 RCTs (n = 638) were included. Four studies showed a medium or large standardized between-group effect size (Cohen’s d) in favor of somatosensory stimulation, in relation to: customized insoles (d = 0.527), taping (d = 0.687), and electrical stimulation (two studies: d = 0.690 and d = 1.984). Although limited by study quality and heterogeneity of interventions and outcomes, with only one study’s results statistically significant, several interventions showed potential for benefit, exceeding the minimally important difference for gait speed. Further research with larger trials is required. This unfunded systematic review was registered with PROSPERO (number CRD42022321199).

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 effect of age, sex and a firm-textured surface on postural control

In previous studies, the influence of plantar sensation has been examined using various textured surfaces with different stiffness materials to assess static balance. This study investigated the effects of a Firm Textured Surface (FTS) along with age and sex-related influences on postural control under different visual conditions. Forty subjects (20 elderly, 10 males, mean age 68.30, 10 females, mean age 68.00, and 20 young people, 10 males, mean age 25.45, 10 females, mean age 27.30) participated in this study maintained a quiet standing on FTS, foam and firm surfaces with eyes open and closed. The center of pressure displacement (CoP_DISP), CoP velocity (CoP_VEL), and sway velocity of the CoP in anteroposterior (AP) and mediolateral (ML) direction (V_A/P and V_M/L) were measured. FTS was associated with lower postural sway measures in both the groups with eyes open and closed. However, the foam surface showed the worst results in all postural parameters under all experimental conditions. Separate four-way ANOVAs were applied to each dependent variable. The main effects of surface (p < 0.0001), vision (p < 0.0001) and age (p < 0.0001 for CoP_DISP, CoP_VEL and V_A/P; p = 0.0003 for V_M/L) were significant in each of the four fitted models. Sex was never significant, either as a main effect or an interaction with other experimental factors. Eyes open were able to reduce the negative effects of the foam surfaces but without vision the proprioceptive sensory system cues of the body state become more important for maintaining balance. A good stimulation with rigid texture should be considered as relief to reduce the physiological-related decline of afferent information with age.

Mechanical Plantar Foot Stimulation in Parkinson's Disease: A Scoping Review

Background: Parkinson′s disease (PD) is the second most prevalent neurodegenerative disease in older individuals. Neurorehabilitation-based interventions such as those improving gait are crucial for a holistic approach and to limit falls. Several studies have recently shown that mechanical plantar foot stimulation is a beneficial intervention for improving gait impairment in PD patients. The objective of this scoping review is to evaluate the beneficial effects of this stimulation on gait parameters, and to analyse protocols of foot stimulation and other effects in non-motor symptoms. Relevant articles were searched in the Medline database using Pubmed and Scopus, using the primary search terms ‘foot stimulation’ OR ‘plantar stimulation’ AND ‘Parkinson’s disease*’. Several protocols have been used for mechanical plantar foot stimulation (ranging from medical devices to textured insoles). The gait parameters that have been shown to be improved are stride length and walking speed. The beneficial effects are achieved after both acute and repeated plantar foot stimulation. Beneficial effects are observed in other organs and systems, such as muscle activation, brain connectivity, cardiovascular control in the central nervous system, and the release of brain-derived neurotrophic factor and cortisol in blood added evidence about this intervention’s impact on brain function. Mechanical plantar foot stimulation is a safe and effective add-on treatment able for improving gait impairments in PD patients during the L-dopa off state. Randomized and controlled clinical trials to study its eventual potentiating effect with different pharmacotherapy regimens are warranted.

Effectiveness of Warm-Up Routine on the Ankle Injuries Prevention in Young Female Basketball Players: A Randomized Controlled Trial

Background and Objectives: Ankle joint is the most common site of injury for basketball athletes. An effective warm-up (WU) is a period of preparatory exercise to improve training performance and reduce sports injuries. Continuous examination of effective WU routines in basketball players is a necessity. The aim of this study was to investigate the effects of general and combined warm up on ankle injury range of motion (ROM) and balance in young female basketball players. Materials and Methods: A sample of 28 young female basketball players were randomly allocated to either global warm up control group (GWU) (n = 11) or combined warm up experimental group (CWU) (n = 17). All participants performed 7-min of run. The CWU group performed a single leg stance barefoot with eyes closed, plank forearm position and triceps sural stretching. Participants in GWU performed walking ball handling and core stability using a Swiss ball. Both WU routines were conducted 3 times per week for 10 weeks. Outcome measurements were the Stabilometric platform and dorsiflexion lunge test. Results: Twenty-eight young female basketball players completed the study. Participants in the experimental group improved significantly in the range of motion (ROM) in right and left ankle and the center of pressure displacement (CoP). The control group did not show any changes in ankle dorsiflexion and a significant reduction in all body balance parameters. Conclusions: An 8-min combined warm-up routine for 10 weeks improves the ankle dorsiflexion ROM and CoP displacement that plays a key role in ankle injuries prevention in basketball players. Further studies are strongly needed to verify our findings.

The immediate effect of plantar stimulation on dynamic and static balance: A randomized controlled trial

OBJECTIVE

To examine the immediate effect on dynamic and static balance of a manual protocol of plantar stimulation in healthy subjects.

MATERIALS AND METHOD

Of the 144 healthy and physically active volunteers recruited, 98 subjects participated. Subjects were randomly assigned and allocated to the experimental group (EG) (n= 50), in which a 10-min manual protocol of plantar stimulation was applied on the right foot, or to the control group (CG) (n= 48). The change scores of the modified Star Excursion Balance Test (mSEBT) and the Unipedal Stance Test (UPST) were used to assess the immediate effect of the protocol on dynamic and static balance, respectively.

RESULTS

In the dynamic balance, a group effect was found in the anterior direction, posteromedial direction and composite scores of the mSEBT when groups were compared by limb. Changes in the posteromedial direction of both limbs (right limb: p= 0.002, left limb: p= 0.05) and composite score of the right limb (p= 0.009) were significantly greater in the EG versus the CG. Non-significant results were found in the static balance (UPST time).

CONCLUSIONS

The application of a 10-minute manual stimulation protocol without joint mobilization, addressed to stimulate the plantar cutaneous mechanoreceptors, could elicit benefits on dynamic balance. This improvement was observed bilaterally even though only one plantar surface was stimulated. As balance deficits may impair functional movements and regular training in sports, this intervention aims to ameliorate dynamic balancing ability could improve the functional recovery of sport gestures.

The effects of textured materials on static balance in healthy young and older adults: A systematic review with meta-analysis

BACKGROUND

Standing on textured materials can improve static balance, potentially by modulating somatosensory inputs from the soles of the feet.

RESEARCH QUESTION

To synthesise and quantify the immediate effects of textured materials on static balance in healthy young and older adults.

METHODS

Primary outcomes were the centre of pressure (COP) displacement and velocity, during eyes open and eyes closed conditions. Ten crossover studies (n = 318, 58% female) met the inclusion criteria. A random effects meta-analysis model derived pooled standardised mean differences (SMD; Hedges g) to quantify the effects of textured materials. Heterogeneity was quantified with the tau-statistic (τ). A 95% prediction interval quantified the likely range of true effects on COP outcomes in similar future studies.

RESULTS

There was a small to moderate beneficial effect for textured materials vs control conditions in: COP displacement during both eyes open (SMD: 0.29; 95% CI -0.06 to 0.64; τ = 0.32) and eyes closed (SMD: 0.75; 95% CI 0.18 to 1.33; τ = 0.55). A trivial to small beneficial effect was observed in COP velocity during eyes open (SMD: 0.14; 95% CI -0.14 to 0.43; τ = 0.18) and eyes closed (SMD: 0.20; 95% CI 0.01 to 0.40; τ = 0.18) for textured materials. The 95% prediction intervals showed texture may not consistently provide beneficial results across studies for all outcomes: COP displacement EC (-0.61 to 2.12), EO (-0.54 to 1.12), COP velocity EC (-0.27 to 0.68) and EO (-0.44 to 0.73).

SIGNIFICANCE

Overall, textured materials improved balance, but these effects were heterogeneous. This research may therefore inform applied investigations into balance improvements for healthy populations, for example, in functional movements and sports.