Light and heavy touch reduces postural sway and modifies axial tone in Parkinson's disease

Analyzing the Differences in the Degree of Force Application Between Novice and Expert Physiotherapists Using a Muscle Deformation Sensor

BACKGROUND

Training physiotherapists require substantial experience and a lengthy period of time to achieve proficiency. However, establishing an objective method for quantifying the degree of force applied during treatment remains elusive, making training difficult.

OBJECTIVES

This study aims to clarify the difference in the degree of force application between novice and expert physiotherapists using muscle deformation sensors and to assist in teaching.

METHODS

A muscle deformation sensor array was utilized to capture the muscle bulging (muscle deformation), and the degree of force was visualized. The experiment involved two types of physiotherapy: upper and lower extremity exercises. Subsequently, the muscle deformation value and standard deviations of the muscle deformation data obtained were compared.

RESULTS

Significant differences between novices and experts were observed in forearm muscle deformation values and standard deviations across both types of physiotherapies (p<0.05). Additionally, a distinction was observed in the left lower limb flexor muscles during upper extremity exercise (p<0.05).

CONCLUSION

The results of this survey showed notable differences in the degree of force application between novices and experts, as demonstrated by our findings. Moreover, these implications extend beyond physiotherapy to sports, hobbies, and the teaching of traditional skills.

Changes in Standing Postural Control Ability in a Case of Spinocerebellar Ataxia Type 31 With Physical Therapy Focusing on the Center of Gravity Sway Variables and Lower Leg Muscle Activity

Spinocerebellar degeneration (SCD) is a progressive disease characterized by cerebellar ataxia or the posterior spinal cord. Among these, spinocerebellar ataxia type 31 (SCA31) is genetically more common in the Japanese population and is characterized by pure ataxia, resulting in severe disturbances in postural balance, with common falls. Therefore, rehabilitation is important to improve postural balance. Light touch is a known method of reducing postural sway, which acts with the light touching of an object with the body. We herein present a case of a patient with SCA31 who was trained in a standing position by lightly touching the back of the body to a wall surface. Dynamic interarticular coordination exercises were also performed as part of the rehabilitation program. As a result, even in the progressive SCA31, improvements in standing postural balance and activities of daily living contributed to improvements in the patient's postural balance. We followed the progress of postural control ability using the center of gravity sway measurement and electromyography and described some interesting characteristics of the patient's postural control ability in this report.

The effect of a contralateral foot touch on stability of one-leg stance in young adults: an exploratory study

PURPOSE

Previous studies demonstrated that providing light finger touch to a stationary object leads to reduced body sway. The focus of the current exploratory study was on the investigation of postural sway during one-leg stance when light touch is provided by the contralateral foot.

METHODS

Eleven healthy young adults participated in the study. They stood on the top of the force platform with eyes open and on their dominant leg with no touch and with a touch from the contralateral foot applied to the stance leg. Medial arch, heel, and big toe of the contralateral foot were used to touch the medial malleolus or mid shank of the stance leg. The excursion, velocity, and sway area of the centre of pressure were obtained and analysed.

RESULTS

Standing with light touch from the contralateral foot to the medial malleolus resulted in significantly smaller postural sway as compared to standing with no touch (p < 0.05). There was no difference in the study outcomes between conditions of standing with a touch applied by the medial arch, heel, or big toe to the stance leg.

CONCLUSIONS

The results of the study suggest that the application of light touch provided by a contralateral foot could be an effective strategy for enhancing body stability when no external support is available. The study outcome provides a foundation for future studies exploring ways to enhance balance control during one-leg stance.

Therapeutic Devices for Motor Symptoms in Parkinson’s Disease: Current Progress and a Systematic Review of Recent Randomized Controlled Trials

Background

Pharmacotherapy is the first-line treatment option for Parkinson’s disease, and levodopa is considered the most effective drug for managing motor symptoms. However, side effects such as motor fluctuation and dyskinesia have been associated with levodopa treatment. For these conditions, alternative therapies, including invasive and non-invasive medical devices, may be helpful. This review sheds light on current progress in the development of devices to alleviate motor symptoms in Parkinson’s disease.

Methods

We first conducted a narrative literature review to obtain an overview of current invasive and non-invasive medical devices and thereafter performed a systematic review of recent randomized controlled trials (RCTs) of these devices.

Results

Our review revealed different characteristics of each device and their effectiveness for motor symptoms. Although invasive medical devices are usually highly effective, surgical procedures can be burdensome for patients and have serious side effects. In contrast, non-pharmacological/non-surgical devices have fewer complications. RCTs of non-invasive devices, especially non-invasive brain stimulation and mechanical peripheral stimulation devices, have proven effectiveness on motor symptoms. Nearly no non-invasive devices have yet received Food and Drug Administration certification or a CE mark.

Conclusion

Invasive and non-invasive medical devices have unique characteristics, and several RCTs have been conducted for each device. Invasive devices are more effective, while non-invasive devices are less effective and have lower hurdles and risks. It is important to understand the characteristics of each device and capitalize on these.

Staying UpRight in Parkinson's disease: A pilot study of a novel wearable postural intervention

OBJECTIVES

This interventional pilot study aimed to 1) examine whether a novel wearable vibro-tactile feedback device ('UpRight Go') is effective and feasible to improve postural alignment in Parkinson's disease (PD); 2) explore relationships between postural alignment and attention in PD; 3) explore effect of vibro-tactile device on balance and gait; and 4) gain initial feedback on the use of the vibro-tactile device in the laboratory and at home.

METHODS

25 people with PD sat, stood and walked for two-minutes without and with the UpRight device attached to their upper backs to provide feedback on postural alignment in the laboratory. A sub-group (n = 12) wore the UpRight device at home for 60 min. per day for 7-days of postural feedback. Subjective feedback on use of the device was obtained in the laboratory and at the end of the 7-day period. The primary outcome for this study was posture measured by verticality of inertial measurement units (IMUs) at the neck, trunk and low back, which was done with and without the UpRight device. Secondary outcomes included clinical measures of posture, subjective feedback on the device, computerized attention measures, gait and balance.

RESULTS

Neck postural alignment in PD was significantly improved (reduced neck flexion) with the UpRight during sitting and standing in both clinical measures (p = 0.005) and IMU outcomes (p = 0.046), but trunk and low back posture did not change. There was no change in postural alignment during walking with the UpRight. Postural alignment response was related to attentional capabilities. Many subjects (68 %) reported that they felt a benefit from the UpRight and most participants reported that the device was acceptable (Lab use; 72 %, Home use; 75 %).

CONCLUSION

The UpRight Go feedback device may improve neck/upper-back posture in PD during sitting and standing, but not during walking. Postural alignment response to the device may depend on attentional mechanisms.

The effects of light touch cue on gait initiation in patients with Parkinson's disease

INTRODUCTION

One of the common impairments in patients with Parkinson's disease (PD) is disturbance of gait initiation. A light touch cue improves postural stability in patients with PD. Little is known about the effects of a light touch cue on gait initiation. This study investigated the effects of a light touch on gait initiation in patients with PD.

METHODS

This study was a cross-sectional study design. Sixteen patients with PD (Hoehn & Yahr stage 2-3) participated in the study and were evaluated two gait conditions (no touch (NT) and light touch (LT) conditions). Gait initiation was divided into 5 events including event A, B, C, D, and E. Outcome measures included maximum center of pressure (COP) displacement and velocity in anteroposterior (AP) and mediolateral (ML) directions, and the first step time.

RESULTS

Participants with LT had greater COP displacement compared with the NT condition in all events of gait initiation except COP-AP displacement in event D. Additionally, the COP velocity in LT condition was faster than the NT condition in COP-ML velocity in event A, COP-AP velocity in event B, COP-AP velocity and COP-ML velocity in event C. Moreover, participants with LT presented significantly shorter the first step time than the NT condition.

CONCLUSIONS

These findings demonstrated that a light touch cue improved gait initiation in patients with PD by increased weight shifting to initial stance limb, increased postural stability of stance limb, increased velocity of weight transfer toward stance limb, and a shortened first step time.

The effects of light touch on gait and dynamic balance during normal and tandem walking in individuals with an incomplete spinal cord injury

STUDY DESIGN

Prospective cross-sectional study OBJECTIVES: To investigate the effect of adding haptic input during walking in individuals with incomplete spinal cord injury (iSCI).

SETTING

Research laboratory.

METHODS

Participants with iSCI and age- and sex-matched able-bodied (AB) individuals walked normally (SCI n = 18, AB n = 17) and in tandem (SCI n = 12, AB n = 17). Haptic input was added through light touch on a railing. Step parameters, and mediolateral and anterior-posterior margins of stability (means and standard deviations) were calculated. Surface electromyography data were collected bilaterally from the tibialis anterior (TA), soleus (SOL), and gluteus medius (GMED) and integrated over a stride. Repeated measures ANOVAs examined within- and between-group differences (α = 0.05). Cutaneous and proprioceptive sensation of individuals with iSCI were correlated to changes in outcome measures that were affected by haptic input.

RESULTS

When walking normally, adding haptic input decreased stride velocity, step width, stride length, MOS_ML, MOS_ML_SD, MOS_AP, and MOS_AP_SD, and increased GMED activity on the limb opposite the railing. During tandem walking, haptic input had no effect; however, individuals with iSCI had a larger step width SD and MOS_ML_SD compared with the AB group. Sensory abilities of individuals with iSCI were not correlated to any of the outcome measures that significantly changed with added haptic input.

CONCLUSIONS

Added haptic input improved balance control during normal but not in tandem walking. Sensory abilities did not impact the use of added haptic input during walking.

Modified desk height helps children with cerebral palsy perform sit-to-stand

Aim: Children with cerebral palsy (CP) have difficulties performing activities that require the use of fundamental motor skills such as sit-to-stand (STS). In this study, we used a height adjustable chair and desk to investigate the role of desk support in STS and how it might benefit children with CP. Methods: Seventeen typically developing children (TDC), average age = 9.7 years, and 28 children with CP (Gross Motor Function Classification System [GMFCS] I and II), average age = 10.3 years, participated in the test. Elapsed time and body sway were measured using a pressure mat and load cell while each child performed a STS task. Two different desk heights were tested for time consumption and sway under the condition of hands-on-desk and arms-crossed. Results: We found that the elapsed time of hands-on-desk with the elbow flexion height was the shortest (p < 0.05). Sway amount was also significantly reduced for all children when they used the table for STS (p < 0.05). Conclusion: Results of this study may be a useful reference in rehabilitation training and designing a desk height beneficial for children with CP.Implications for RehabilitationBetter performance of sit-to-stand for a child with cerebral palsy could be made by a desk supportElapsed time during preparation period for sit-to-stand could be reduced by desk support for all CP childrenSway amount during sit-to-stand could be reduced by desk support, especially for the CP children with GMFCS level IIDesk height is an important parameter and should be studied in detail.

Effects of a core stabilization training program on balance ability in persons with Parkinson's disease: a randomized controlled trial

OBJECTIVE

To explore the effects of an eight-week core stability program on balance ability in persons with Parkinson's disease.

DESIGN

Randomized controlled trial.

SETTING

A local Parkinson's association.

SUBJECTS

A total of 44 participants with a clinical diagnosis of Parkinson's disease were randomly assigned to an experimental (n = 22) or control group (n = 22).

INTERVENTION

The experimental group received 24 sessions of core training, while the control group received an intervention including active joint mobilization, muscle stretching, and motor coordination exercises.

MAIN MEASURES

The primary outcome measure was dynamic balance evaluated using the Mini-Balance Evaluation Systems Test. Secondary outcomes included the balance confidence assessed with the Activities-specific Balance Confidence Scale and standing balance assessed by the maximal excursion of center of pressure during the Modified Clinical Test of Sensory Interaction on Balance and the Limits of Stability test.

RESULTS

After treatment, a significant between-group improvement in dynamic balance was observed in the experimental group compared to the control group (change, 2.75 ± 1.80 vs 0.38 ± 2.15, P = 0.002). The experimental group also showed a significant improvement in confidence (change, 16.48 ± 16.21 vs 3.05 ± 13.53, P = 0.047) and maximal excursion of center of pressure in forward (change, 0.86 ± 1.89 cm vs 0.17 ± 0.26 cm, P = 0.048), left (change, 0.88 ± 2.63 cm vs 0.07 ± 0.48 cm, P = 0.010), and right (change, 1.63 ± 2.82 cm vs 0.05 ± 0.17 cm, P = 0.046) directions of limits of stability compared to the control group.

CONCLUSION

A program based on core stability in comparison with non-specific exercise benefits dynamic balance and confidence and increases center of mass excursion in patients with Parkinson's disease.

Effects of active and passive light-touch support on postural stability during tandem standing

[Purpose] Light-touch support (consisting of a load <100 g) is useful for reducing postural sway while standing and walking. However, it is unclear which types of touch and somatosensory inputs are more effective for improving postural control. This study aimed to clarify the effects of active and passive light-touch support, with and without visual information, on postural stability during tandem standing. [Participants and Methods] Eleven young healthy adults maintained tandem standing for 30 s under six conditions. The independent variables were light-touch condition (no, active or passive) and visual condition (eyes open or closed). Postural sway, as measured using a force plate, was considered to indicate postural stability. [Results] There was significantly less postural sway with active light touch compared with passive and no touch. Passive light touch resulted in significantly less sway than no touch. In addition, there was less postural sway with active light compared to passive light touch, especially with the eyes closed. The light-touch support force did not differ between conditions. [Conclusion] Both active and passive light-touch improved postural stability in comparison to no-touch. Active light-touch support significantly improved postural stability. These results could be used to inform therapeutic interventions within clinical settings.

Trunk velocity-dependent Light Touch reduces postural sway during standing

Light Touch (LT) has been shown to reduce postural sway in a wide range of populations. While LT is believed to provide additional sensory information for balance modulation, the nature of this information and its specific effect on balance are yet unclear. In order to better understand LT and to potentially harness its advantages for a practical balance aid, we investigated the effect of LT as provided by a haptic robot. Postural sway during standing balance was reduced when the LT force (~ 1 N) applied to the high back area was dependent on the trunk velocity. Additional information on trunk position, provided through orthogonal vibrations, further reduced the sway position-metric of balance but did not further improve the velocity-metric of balance. Our results suggest that limited and noisy information on trunk velocity encoded in LT is sufficient to influence standing balance.

Fingertip-Coupled Spindle Signaling Does Not Contribute to Reduce Postural Sway Under Light Touch

The details of how light touch (LT) of a stable surface reduces postural sway are still not well known. We hypothesized that removal of feedback provided by muscle afferents of the touching fingertip would increase postural sway in standing subjects. Eleven participants stood upright on a force plate with eyes closed and on an unstable surface. The experimental conditions involved two different finger positions: with partial muscle afferents (PMA), which includes sensory information from the fingertip flexor muscles, and no muscle afferents (NMA), without information from either fingertip flexor or extensor muscles. In the control condition, the participants kept the same posture, but with no finger touch (NT). Postural sway in both anteroposterior (AP) and mediolateral (ML) axes were recorded. Results showed that LT decreased all sway quantifiers as compared with the NT condition. The withdrawal of information from the touch finger muscle afferents (NMA condition) did not increase postural sway. Actually, there was a small, albeit statistically significant, decrease in the variability of center of pressure displacement in the AP direction. These results indicate that in some cases, muscle afferent input may either not contribute or even worsen the overall quality of sensory feedback from a given body segment, leading to no improvement or even a slightly decreased performance of the motor control system (evaluated by means of levels of postural sway in the present investigation). The results suggest that non-spindle fingertip afferents provide the bulk of the sensory feedback associated with the fingertip that is touching a ground-referenced object during quiet standing under LT.

From One to Two: Can Visual Feedback Improve the Light Touch Effects on Postural Sway?

The postural control is improved by implicit somatosensory information from lightly touching a rigid bar or explicit visual information about the postural sway. Whether these two additional sources provided at the same time further reduce the postural sway is still unknown. Participants stood on a force plate as quiet as possible lightly touching the bar while received or not visual feedback of the center of pressure position on a monitor screen. Postural sway reduced similarly with the light touch regardless of the additional visual feedback. The findings suggested that providing explicit visual feedback of the center of pressure does not increase the light touch effects on the postural sway. The importance of the implicit somatosensory information on postural control is discussed.

Short-latency muscle response patterns to multi-directional, unpredictable perturbations to balance applied to the arm are context dependent

A number of studies have shown that sensory inputs from the hand can have a profound effect in stabilizing upright posture. This suggests that the central nervous system can extract information about body motion and external forces acting on the body from cutaneous sensory signals. We have recently shown that the central nervous system determines the direction of an unpredictable force applied to the hand so rapidly that it is able to activate ankle muscles in advance of the perturbing effect that this force has at the ankles. In this study we investigate whether this rapid change in activation of lower limb muscles is an invariant response determined by the pattern of somatosensory information arising from sensory receptors in the hand or whether it adapts to changes in postural stability. We manipulated lateral stability of upright stance by changing stance width which had no effect on the activation of upper limb muscles or hand kinematics, but produced profound changes in the activation patterns of lower limb muscles when perturbations were in the medial/lateral direction without affecting the activation patterns of muscles when perturbations were in the anterior/posterior direction.

Pre- and unplanned walking turns in Parkinson's disease - Effects of dopaminergic medication

Although dopaminergic medication improves functional mobility in individuals with Parkinson's disease (PD), its effects on walking turns are uncertain. Our goals was to determine whether dopaminergic medication improves preplanned and unplanned walking turns in individuals with PD, compared to healthy controls. Nineteen older adults with mild-to-moderate PD and 17 healthy controls performed one of the following three tasks, presented randomly: walking straight, or walking and turning 180° to the right or left. The walking direction was visually cued before starting to walk (preplanned) or after (unplanned, i.e., 0.6m before reaching the turning point). Subjects with PD were assessed off dopaminergic medication (OFF) and on dopaminergic medication (ON) medication. Turning strategy (step and spin turns), turning performance (turning distance and body rotation) and walking pattern were analyzed for three turning steps. Irrespective of medication state and turning condition, step and spin turns followed a nearly 50:50 distribution. After intake of dopaminergic medication, subjects with PD increased their turning distance but not the amount of body rotation or their walking pattern. Compared to controls, turning impairments in subjects with PD remained while ON medication and problems regulating step width were the most prominent features of their walking pattern. Specifically, subjects with PD turned with narrower cross-over steps, i.e. when the external foot crossed over the line of progression of the internal leg. We conclude that turning impairments remained even after dopaminergic medication and problems modulating step width appears to be a critical feature for turning in PD.

The Mini-BESTest--a clinically reproducible tool for balance evaluations in mild to moderate Parkinson's disease?

Background

The Mini-BESTest is a clinical balance test that has shown a high sensitivity in detecting balance impairments in elderly with Parkinson's disease (PD). However, its reproducibility between different raters and between test occasions has yet to be investigated in a clinical context. Moreover, no one has investigated the reproducibility of the Mini-BESTest's subcomponents (i.e. anticipatory postural adjustments; postural responses; sensory orientation and dynamic gait).

We aimed to investigate the inter-rater and test-retest reproducibility (reliability as well as agreement) of the Mini-BESTest, as well as its subcomponents, in elderly with mild to moderate PD, performed under conditions assimilating clinical practice.

Method

This was an observational measurement study with a test-retest design.

Twenty-seven individuals with idiopathic PD (66 - 80 years, mean age: 73; Hoehn & Yahr: 2-3; 1-15 years since diagnosis) were included. Two test administrators, having different experiences with the Mini-BESTest, administered the test individually, in separate rooms in a hospital setting. For the test-retest assessment, all participants returned 7 days after the first test session to perform the Mini-BESTest under similar conditions. Intra-class correlation coefficients (ICC_2.1), standard error of measurement (SEM_agreement), and smallest real difference (SRD) were analyzed.

Results

The Mini-BESTest showed good reliability for both inter-rater and test-retest reproducibility (ICC = 0.72 and 0.80). Regarding agreement, the measurement error (SRD) was found to be 4.1 points (accounting for 15% of the maximal total score) for inter-rater reproducibility and 3.4 points (12% of the maximal total score) for test-retest reproducibility. The investigation of the Mini-BESTest's subcomponents showed a similar pattern for both inter-rater and test-retest reproducibility, where postural responses had the largest proportional measurement error, and sensory orientation showed the highest agreement.

Conclusions

Our findings indicate that the Mini-BESTest is able to distinguish between individuals with mild to moderate PD; however, when used in clinical balance assessments, the large measurement error needs to be accounted for.

Effect of light touch on postural sway in individuals with balance problems: a systematic review

The aim of the present review was to examine the experimental, case-control studies that investigated the effect of light touch on postural sway in individuals with balance problems due to aging, brain lesion or other motor or sensory deficits. Articles published before the end of March of 2013 were searched in PubMed, Scielo and Lilacs databases using terms related to postural control and sensory information. Twelve studies that assessed the postural sway of individuals with balance problems during quiet standing with the light touch using a force plate were reviewed. Two reviewers rated all selected articles as having good quality. The effect of light touch on postural control was reported by all eligible studies regardless of the cause of the balance problem of the participants. Such effect was more evident when the applied vertical force was greater than 1N, but if individuals with poor balance took more advantage of the light touch than healthy ones it depended on the source of their balance problems and not the amount of the applied force. These findings suggested that the maintenance of the fingertip lightly touching an external surface could provide additional somatosensory information for individuals with poor balance and then it could be used as a strategy to improve the control of upright standing during intervention programs.