The effect of shoe wedges and lifts on symmetry of stance and weight bearing in hemiparetic individuals

Asymmetric shoe height induces reactive changes in gait kinematics but not kinetics in healthy young adults

BACKGROUND

Footwear interventions are a potential avenue to correct walking asymmetry in neurologic populations, such as stroke. However, the motor learning mechanisms that underlie the changes in walking imposed by asymmetric footwear are unclear.

RESEARCH QUESTION

The objectives of this study were to examine symmetry changes during and after an asymmetric shoe height intervention in (1) vertical impulse and (2) spatiotemporal gait parameters and (3) joint kinematics, in healthy young adults METHODS: Eleven healthy young adults (3 males, 8 females; 21.2 ± 3.1 years old) participated in this study. Participants walked on an instrumented treadmill at 1.3 m/s for four conditions: (1) a 5-minute familiarization with equal shoe height, (2) a 5-minute baseline with equal shoe height, (3) a 10-minute intervention, where participants walked with asymmetric shoe height with a 10 mm shoe insert in one shoe, and (4) a 10-minute post-intervention, where participants walked with equal shoe height. Asymmetry in kinetics and kinematics were used to identify changes during intervention and aftereffects, a hallmark of feedforward adaptation RESULTS: Participants did not alter vertical impulse asymmetry (p = 0.667) nor stance time asymmetry (p = 0.228). During the intervention, step time asymmetry (p = 0.003) and double support asymmetry (p < 0.001) were greater compared to baseline. Leg joint asymmetry during stance (Ankle plantarflexion: p < 0.001; Knee flexion: p < 0.001; Hip extension: p = 0.011) was greater during the intervention compared to baseline. However, changes in spatiotemporal gait variables and joint mechanics did not demonstrate aftereffects.

SIGNIFICANCE

Our results show that healthy human adults change gait kinematics, but not weight-bearing symmetry with asymmetrical footwear. This suggests that healthy humans prioritize maintaining vertical impulse by changing their kinematics. Further, the changes in gait kinematics are short-lived, suggesting feedback-based control, and a lack of feedforward motor adaptations.

Neuromechanical control of impact absorption during induced lower limb loading in individuals post-stroke

Decreased loading of the paretic lower limb and impaired weight transfer between limbs negatively impact balance control and forward progression during gait in individuals post-stroke. However, the biomechanical and neuromuscular control mechanisms underlying such impaired limb loading remain unclear, partly due to their tendency of avoiding bearing weight on the paretic limb during voluntary movement. Thus, an approach that forces individuals to more fully and rapidly load the paretic limb has been developed. The primary purpose of this study was to compare the neuromechanical responses at the ankle and knee during externally induced limb loading in people with chronic stroke versus able-bodied controls, and determine whether energy absorption capacity, measured during induced limb loading of the paretic limb, was associated with walking characteristics in individuals post-stroke. Results revealed reduced rate of energy absorption and dorsiflexion velocity at the ankle joint during induced limb loading in both the paretic and non-paretic side in individuals post-stroke compared to healthy controls. The co-contraction index was higher in the paretic ankle and knee joints compared to the non-paretic side. In addition, the rate of energy absorption at the paretic ankle joint during the induced limb loading was positively correlated with maximum walking speed and negatively correlated with double limb support duration. These findings demonstrated that deficits in ankle dorsiflexion velocity may limit the mechanical energy absorption capacity of the joint and thereby affect the lower limb loading process during gait following stroke.

Effects of constraint-induced movement therapy for the lower extremity among individuals post-stroke: A randomized controlled clinical trial

BACKGROUND: Stroke often leads to lower extremity impairments that significantly hinders functional recovery. OBJECTIVE: To investigate the effectiveness of constraint-induced movement therapy for the lower extremity (CIMT-LE) for improving balance and ambulation among people post-stroke. METHODS: A randomized controlled, single-blinded clinical trial was conducted. Participants were recruited and randomized into one of two groups: CIMT-LE group and control. Outcome measures were the Fugl-Meyer assessment of lower extremity, Berg balance scale, ten-meter walk test and six-minute walk test. Outcome measures were collected at baseline, following the conclusion of the therapeutic programs and after three months. RESULTS: 38 participants were enrolled in the study (19 in each group). No significant differences were found between groups at baseline. At the conclusion of therapeutic programs, both groups showed significant changes compared to baseline. However, changes seen in the CIMT-LE were clinically significant. Further, at three months following the conclusion of the program, the recorded improvements were retained by participants. CONCLUSION: A CIMT-LE program compared to an intensity-matched conventional program yielded significant clinical improvements among people post-stroke. These improvements were seen in lower extremity motor recovery, postural balance and gait speed. Furthermore, these improvements were retained three months following the conclusion of the therapeutic program.

P, Misri Z, Pai S. Effect of Compelled Body Weight Shift (CBWS) Therapy in Comparison to ProprioceptiveTraining on Functional Balance, Gait, andMuscle Strength Among Acute Stroke Subjects

Background:

The majority of poststroke individuals tend to exhibit reduced loading over the paretic lower extremity, leading to increased postural sway, and gait asymmetry predisposing to a higher number of falls. Compelled body weight shift (CBWS) therapy is an innovative method aimed to force body weight shift toward the paretic extremity. Proprioceptive training (PT) is another method that improves balance ability contributing to the increase in muscle activity. Both the CBWS and PT have been shown to improve the quality of life in stroke subjects.

Aims and Objectives:

The aim of this study is to compare the effects of CBWS therapy and PT in improving balance, kinematic gait parameters, and muscle strength among acute stroke patients.

Methods:

Thirty subjects were nonrandomly divided into two groups where both groups received routine physiotherapy for two weeks in addition to which the CBWS group incorporated a 15 mm platform placed under the unaffected extremity while the PT group included incorporated proprioceptive exercises on the ground and foam mat. Functional balance, functional mobility, videographic analysis of degrees of hip flexion, knee hyperextension, and ankle dorsiflexion along with gait speed and spatiotemporal gait parameters were obtained.

Results:

The pre-post analysis within both groups revealed statistically significant improvement in all parameters except for the kinematic parameters of gait. However, no statistically significant difference was observed between the CBWS and PT groups.

Conclusion:

CBWS can be used as an alternative to PT in the rehabilitation of stroke patients concerning balance and gait. CBWS provided during active treatment sessions results as effective as those seen as a result of all-day therapy.

EMG-Triggered Pedaling Training on Muscle Activation, Gait, and Motor Function for Stroke Patients

This study aimed to determine the effects of electromyography (EMG)-triggered pedaling training to improve motor functions in the lower extremities, muscle activation, gait, postural balance, and activities of daily living in stroke patients. Subjects were randomly allocated to two groups: the EMG-triggered pedaling training group (EMG-PTG, n = 21) and the traditional pedaling training group (TPTG, n = 20). Both groups trained five times per week for four weeks, with 50 min per session. Lower extremity motor function was assessed using the Fugl–Meyer Assessment (FMA). Muscle activation of the four muscles of the lower extremities was assessed using eight-channel electromyography, while gait ability was assessed using GaitRite. Postural balance was assessed using the Berg balance scale (BBS), the timed up and go (TUG), and functional reach tests (FRT). Daily activities were assessed using the Modified Barthel Index (MBI). For lower extremity motor function, gait ability, balance ability, and activities of daily living, the EMG-PTG showed significant improvement compared to TPTG (p < 0.05). These results suggest that EMG-triggered pedaling training effectively improves lower extremity motor function, muscle activation, gait, postural balance, and activities of daily living in stroke patients.

Effects of orthopedic insoles on postural balance in patients with chronic stroke: A randomized crossover study

BACKGROUND

Orthopedic insoles (OIs) with medial arch support and heel cushion are widely used to manage lower extremity injuries, but their effects on postural balance in patients with chronic stroke have not been adequately explored.

METHODS

Design: Double-blinded, sham-controlled, randomized crossover trial.

PARTICIPANTS

A total of 32 ambulatory patients (20 men and 12 women, aged between 30 and 76 years) with more than 6 months since stroke onset.

INTERVENTIONS

All participants received one assessment session wearing OIs and one session wearing sham insole (SI) in a random order with a 1-day interval.

OUTCOMES

Our primary outcome was the Berg Balance Scale score. Secondary outcomes included the Functional Reach Test, Timed Up and Go test, and computerized posturography. All were performed in both sessions. Subgroup analyses regarding demographic and functional variables were conducted to identify potential responders.

RESULTS

Significant between-insole differences favoring OIs were seen in all clinical tests (P < 0.05), but were seen only in the static medial-lateral sway in computerized posturography assessment (P = 0.04). An approximate 2-point difference in the BBS score favoring OIs was observed in all subgroups, not reaching the minimal clinically important difference.

CONCLUSION

The use of OIs generated small but significant positive effects on improving postural balance among patients with chronic stroke. Additional biomechanical and clinical studies are required to evaluate their potential for routine clinical use.

TRIAL REGISTRATION

NCT03194282.

The effect of a textured insole on anticipatory postural adjustments

PURPOSE

To obtain preliminary data on the effect of a textured insole on postural control.

METHODS

Nine healthy subjects were exposed to external perturbations applied to their shoulders while standing with or without a single textured insole. Body weight distribution and bilateral electromyographic activity (EMG) of trunk and leg muscles were recorded. Onsets of EMG activity of muscles were calculated and analyzed within the interval typical for anticipatory postural adjustments.

RESULTS

When a textured insole was provided under one foot, subjects shifted their body weight towards the contralateral foot. With no insole, the anticipatory onsets of EMG activity of the left and right muscles were symmetrical; when a textured insole was used, the EMG onsets of the muscles on the contralateral side of the body were seen earlier as compared to the insole side. This early activation was more pronounced in the trunk muscles (p < 0.05).

CONCLUSIONS

Using a single textured insole under one-foot induced asymmetry of anticipatory onsets of EMG activity in healthy subjects. The outcome highlights the importance of investigating the role of a single textured insole in control of vertical posture and provides a foundation for future studies focussed on improvement of postural control in individuals with body asymmetry due to unilateral weakness.

Effects of insole on the less affected side during execution of treadmill walking training on gait ability in chronic stroke patients: A preliminary study

BACKGROUND

People who have had hemiplegic stoke generally move more weight to the unaffected side than the affected side, resulting in asymmetrical posture and decreased ability in walking.

OBJECTIVES

This study sought to investigate the effect of inducing a weight shift to the affected side by raising the shoe height of the less affected side using an insole during the execution of treadmill training on gait ability in people with chronic stroke.

METHODS

The subjects were randomly assigned into two groups: insole on less affected side for execution of treadmill walking training (ILTW) group and normal treadmill training (NTW) group. The treadmill training was conducted for 30 minutes per session, 5 times a week, for 4 weeks. A gait analyzer based on body center, Functional Gait Assessment (FGA), Figure-of-Eight Walk Test (F8WT), and 6 min Walk Test (6 MWT), was measured before first intervention and after twentieth treadmill training intervention (Trial registration number is KCT0003830).

RESULTS

The results revealed statistically significant differences between the two groups in the Speed, Cadence, Stride Length/Height, Stride Length, Double Support Duration, Single Support Duration, FGA, F8WT, and 6 MWT of the gait test. In the ILTW group, statistically significant improvements were observed in the Speed, Stride Length/Height, Stride Length, Stance Phase Duration, Swing Phase Duration, Double Support Duration, Single Support Duration, FGA, F8WT, and 6 MWT after execution of training, while in the NTW group, statistically significant improvements were observed only in Speed, Cadence, FGA, F8WT, and 6 MWT.

CONCLUSIONS

ILTW, more than NTW, may improve walking ability in people with chronic stroke as it increases the weight-support ratio by adjusting the shoe height of the unaffected side using an insole.

Constraint-Induced Movement Therapy for Improving Motor Function of the Paretic Lower Extremity After Stroke

A 56-yr-old woman with chronic stroke and gait dysfunction was recruited for this study. A lower-extremity constraint-induced movement therapy protocol was given consisting of 3.5 hrs/d of supervised intervention activities on 10 consecutive weekdays. Motor training was intensive and involved shaping. In addition, a group of behavior management strategies was used to induce further unsupervised practice and transference of motor skills from the laboratory to real-world situations. Changes in functional mobility, walking speed, balance, level of assistance, perceived quality of movement, and level of confidence while performing daily activities were assessed five times in both the baseline and intervention phases. The outcomes observed after the intervention were determined by calculating the difference between the average scores obtained in both phases. Changes in perceived quality of movement, level of confidence, level of assistance, and balance were observed.

A Randomized Controlled Study Assessing the Effects of a Shoe Lift Under the Nonparetic Leg on Balance Performance in Individuals With Chronic Stroke

BACKGROUND AND PURPOSE

Improvement of balance and postural stability is an important goal in stroke rehabilitation. The purpose of this study was to investigate the effects of a shoe lift under the nonparetic leg on balance function and balance confidence in persons with chronic stroke.

METHODS

Thirty-six individuals with chronic stroke (21 males and 15 females), who were able to walk independently and showed stance asymmetry, were randomized to a shoe insert and a control group. The interventions included a 6-week balance training program, in conjunction with a shoe lift under the nonaffected leg (shoe insert group, n = 18), or balance training alone (control group, n = 18). The outcome measures were weight-bearing asymmetry (WBA), root mean square (RMS) of anterior-posterior (AP) and medial-lateral (ML) center-of-pressure (COP) velocity asymmetry, Berg Balance Scale (BBS), and Activities-specific Balance Confidence (ABC) Scale. These were measured in both groups at baseline, after the intervention, and at a 3-month follow-up. A repeated-measure multivariate analysis of variance was conducted to evaluate the impact of 2 different interventions on balance measures, across the 3 periods.

RESULTS AND DISCUSSION

No significant between-group differences were found for demographics and stroke-related characteristics of participants (P > .05). The outcome measures between the 2 groups were not significantly different at baseline (P > .05). There were between-group differences for WBA and the RMS of AP COP velocity asymmetry after the intervention and at the 3-month follow-up (P < .05). No significant difference in the RMS of ML COP velocity asymmetry, BBS, and ABC was identified between the 2 groups after the intervention and at the 3-month follow-up (P > .05).

CONCLUSION

The results indicated that the use of a shoe lift under the nonaffected leg in the context of a balance training program could result in a greater improvement in static standing balance as compared with balance training alone in an individual with chronic stroke.

TRIAL REGISTRATION

The study was retrospectively registered in the Iranian Registry of Clinical Trials (IRCT20190603043808N1).

Immediate changes in post-stroke gait using a shoe lift on the nonaffected lower limb: A preliminary study

INTRODUCTION

Gait impairment is one of the most important post-stroke complications and is associated with reduced mobility, limitations in activities of daily living and decreased quality of life. Gait recovery is an important goal in post-stroke rehabilitation and shoe lifts have been used on the nonaffected lower limb (NLL) to reduce compensatory strategies such as vaulting, pelvic hiking and hip circumduction during the swing phase of the affected lower limb. Moreover, in clinical practice shoe lifts seem to reduce tripping and the risk of falls.

OBJECTIVE

Evaluate walking speed and functional mobility with and without a 1.5 cm shoe lift under the non-affected lower limb in post-stroke gait.

METHODS

Forty-two subjects with hemiparesis after stroke were evaluated on a single day, under two conditions: with and without a 1.5 cm shoe lift. The assessment sequence was randomized and clinical tests (Ten-meter walk Test - 10MWT and Timed Up and Go - TUG) were performed one after the other.

RESULTS

There was a significant increase in walking speed in the 10MWT and shorter TUG times, with mean differences of 0.78 (CI95% 0.15-1.41, P ≤ 0.001, EF = 0.55) and 0.57 seconds (-0.11-1.25, P = .022, EF = 0.35), respectively.

CONCLUSION

The results showed that the immediate use of 1.5 cm shoe lifts seems to improve gait speed and functional mobility in chronic stroke patients. Further studies should focus on understanding the kinematics strategies and gait pattern alterations caused by shoe lifts under the NLL of post-stroke individuals.

Constraint-Induced Movement Therapy for Lower Extremity Function: Describing the LE-CIMT Protocol

Constraint-induced movement therapy (CIMT) is comprised of a set of techniques shown to produce significant changes in upper extremity (UE) function following stroke and other disorders. The significant positive results obtained with the UE protocol have led to the development of LE-CIMT, an intervention to improve lower extremity (LE) function. However, some modifications of the UE protocol were needed, including omitting use of a restraint device, development of supervised motor training tasks to emphasize movement of the lower limb, and adaptation of the UE Motor Activity Log for the lower extremity. The LE-CIMT protocol includes: (1) intensive supervised training delivered for 3.5 h/d for 10 consecutive weekdays, (2) use of shaping as a strategy for motor training, (3) application of a transfer package, and (4) strongly encouraging use of the more-affected LE with improved coordination. The transfer package consists of several strategies to facilitate transfer of the improved motor skills developed during supervised treatment to everyday situations. Research to date has yielded positive results. However, the intervention protocol continues to evolve. The purpose of this article is to describe the components of the complete LE-CIMT protocol to promote further development and investigation of this approach.

Different weight shift trainings can improve the balance performance of patients with a chronic stroke: A randomized controlled trial

BACKGROUND

Improving balance ability, increasing walking ability, and reducing the occurrence of falls are important objectives in the rehabilitation of stroke patients. Do the posture balance training and the intervention of lateral wedge insoles to improve of balance function and increase walking ability in patients with a chronic stroke?

METHODS

A randomized, controlled trial with concealed allocation, intention-to-treat analysis, and blinded assessors. Participants who had a chronic stroke (onset >6 months) were recruited from the rehabilitation and neurology departments of a hospital in central Taiwan. Subjects were divided into 3 groups: a visual biofeedback balance training group, a lateral wedge group, and a control group; apart from their usual rehabilitation program, and both experimental groups received a 6-week training session program. The primary outcome was the balance computerized adaptive test (balance CAT), and secondary outcome was timed up and go (TUG) test. All subjects were evaluated at the baseline, posttraining (6-week), 1st follow-up (10-week), and 2nd follow-up (18-week).

RESULTS

A total of 56 subjects were participated in this study, including 38 males and 18 females. The mean age of the subjects was 59.1 years old, and the mean time was 43.7 months after the onset of the stroke. This study found the interaction in groups and measurement time points reached statistical significance of the balance CAT and TUG test (F = 5.740, P < .001; F = 2.926, P = .011; respectively). In addition, the performance of both the visual biofeedback training and lateral wedge group was superior to that of the control group.

CONCLUSION

Six-week visual biofeedback training and intervention of 5° lateral wedge insoles can improve the balance ability of patients with a chronic stroke.

TRIAL REGISTRY

http://www.chictr.org.cn, ChiCTR-IPR-15007092.

Exploration of Two Training Paradigms Using Forced Induced Weight Shifting With the Tethered Pelvic Assist Device to Reduce Asymmetry in Individuals After Stroke: Case Reports

Many robotic devices in rehabilitation incorporate an assist-as-needed haptic guidance paradigm to promote training. This error reduction model, while beneficial for skill acquisition, could be detrimental for long-term retention. Error augmentation (EA) models have been explored as alternatives. A robotic Tethered Pelvic Assist Device has been developed to study force application to the pelvis on gait and was used here to induce weight shift onto the paretic (error reduction) or nonparetic (error augmentation) limb during treadmill training. The purpose of these case reports is to examine effects of training with these two paradigms to reduce load force asymmetry during gait in two individuals after stroke (>6 mos). Participants presented with baseline gait asymmetry, although independent community ambulators. Participants underwent 1-hr trainings for 3 days using either the error reduction or error augmentation model. Outcomes included the Borg rating of perceived exertion scale for treatment tolerance and measures of force and stance symmetry. Both participants tolerated training. Force symmetry (measured on treadmill) improved from pretraining to posttraining (36.58% and 14.64% gains), however, with limited transfer to overground gait measures (stance symmetry gains of 9.74% and 16.21%). Training with the Tethered Pelvic Assist Device device proved feasible to improve force symmetry on the treadmill irrespective of training model. Future work should consider methods to increase transfer to overground gait.

The effect of immediate decreasing of weight bearing asymmetry on quiet standing postural control in individuals with chronic stroke

The main patterns characterizing standing posture of hemiparetic patients include: weight-bearing asymmetry (WBA), larger postural sway, asymmetrical contribution of lower limbs to balance control, and increased visual dependency to balance control. The aim of this study was to evaluate the effect of decreasing WBA with the use of a shoe lift, on quiet standing postural control in patients with chronic stroke. Twenty-seven patients participated in this study. Patients completed two tests: 1) quiet standing; and 2) quiet standing while a lift was placed under the non-paretic limb. The following tests were completed on force plates for evaluation: asymmetry of the balance measures (weight bearing, root mean square (RMS) of anterior-posterior (AP) and medial-lateral (ML) center of pressure (COP) velocity), RMS of total AP and ML COP velocity, and AP and ML Romberg quotients. Paired t-tests were used to analyze the data. The mean value of WBA index decreased significantly after using a lift (p < 0.05). However, the changes of the mean value of other postural control parameters were not significant (p > 0.05). The results indicate that there may not be an association between decreased WBA and improved postural control during quiet standing in patients with stroke.

Effects of a sitting boxing program on upper limb function, balance, gait, and quality of life in stroke patients

BACKGROUND

Boxing training including traditional stretching, muscular strength training, and duration training would be considered to be effective for improved functional stretching, dynamic balance, walking speed, and quality of life.

OBJECTIVE

We aimed to investigate upper limb function, balance, gait, and quality of life in stroke patients before and after a sitting boxing program.

METHODS

Twenty-six participants were randomly allocated to a boxing group (n = 13) and control group (n = 13) after the upper limb function, balance, gait, and quality of Life were recorded. The boxing group underwent a sitting boxing program (3 times/week) as well as conventional physical therapy (3 times/week) for 6 weeks. The control group only underwent conventional physical therapy (3 times/week) for 6 weeks.

RESULTS

The Manual Functional Test (MFT), non-affected hand grip, Berg Balance Scale (BBS), velocity moment with eye opened, 10-m Walk Test (10 MWT), and Stroke-Specific Quality of Life questionnaire (SS-QOL) were significantly improved in the boxing group (p < 0.05) and showed significantly greater improvements in the boxing group compared to the control group (p < 0.05) after 6 weeks.

CONCLUSIONS

The sitting boxing program group had positive effects on upper extremity function, balance, gait, and quality of life in stroke patients.

Unilateral Discomfort Increases the Use of Contralateral Side during Sit-to-Stand Transfer

Individuals with unilateral impairment perform symmetrical movements asymmetrically. Restoring symmetry of movements is an important goal of rehabilitation. The aim of the study was to evaluate the effect of using discomfort-inducing devices on movement symmetry. Fifteen healthy individuals performed the sit-to-stand (STS) maneuver using devices inducing unilateral discomfort under the left sole and left thigh or right sole and right thigh and without them. 3D body kinematics, ground reaction forces, electrical activity of muscles, and the level of perceived discomfort were recorded. The center of mass (COM), center of pressure (COP), and trunk displacements as well as the magnitude and latency of muscle activity of lower limb muscles were calculated during STS and compared to quantify the movement asymmetry. Discomfort on the left and right side of the body (thigh and feet) induced statistically significant displacement of the trunk towards the opposite side. There was statistically significant asymmetry in the activity of the left and right Tibialis Anterior, Medial Gastrocnemius, and Biceps Femoris muscles when discomfort was induced underneath the left side of the body (thigh and feet). The technique was effective in causing asymmetry and promoted the use of the contralateral side. The outcome provides a foundation for future investigations of the role of discomfort-inducing devices in improving symmetry of the STS in individuals with unilateral impairment.

Changes of gait parameters following constrained-weight shift training in patients with stroke

[Purpose] This study aimed to investigate the effects of training involving compelled weight shift on the paretic lower limb on gait parameters and plantar pressure distribution in patients with stroke. [Subjects and Methods] Forty-five stroke patients participated in the study and were randomly divided into: group with a 5-mm lift on the non-paretic side for constrained weight shift training (5: constrained weight shift training) (n=15); group with a 10-mm lift on the non-paretic side for constrained weight shift training (10: constrained weight shift training) (n=15); or the control group (n=15). Both, the 5 constrained weight shift training and 10 constrained weight shift training groups underwent constrained weight shift training 5 times per week for 4 weeks, whereas the control group performed ergometer exercises for lower limb muscle strengthening. [Results] The 10 constrained weight shift training group showed a significant increase in the contact surface and impulse of the hindfoot compared to the control group, and the step length and walking speed were significantly longer and faster. [Conclusion] We found that constrained weight shift training on the paretic lower limb is an effective treatment method for improving normal gait pattern in stroke patients.

The effect of isolating the paretic limb on weight-bearing distribution and EMG activity during squats in hemiplegic and healthy individuals

BACKGROUND

Neural reorganization for movement therapy after a stroke is thought to be an important mechanism that facilitates motor recovery. However, there is a lack of evidence for the effectiveness of exercise programs in improving the lower limbs.

OBJECTIVE

We investigated the immediate effect of isolating the paretic limb using different foot positions ((i) foot parallel; both feet parallel, (ii) foot asymmetry; paretic foot backward by 10 cm, and (iii) foot lifting; nonparetic foot lifting by normalization to 25% of knee height) on weight-bearing distribution and electromyography (EMG) of the thigh muscle during squats.

METHODS

In total, 20 patients with hemiplegia and 16 healthy subjects randomly performed three squat conditions in which the knee joint was flexed to 30°. Weight distribution was measured using the BioRescue system. Muscle activity was measured using a surface EMG system.

RESULTS

Patients with hemiplegia exhibited significantly decreased weight bearing on the paretic foot at 0° and 30° knee flexion compared with the nondominant foot of a healthy subject. The muscle activity of the quadriceps was significantly lower in patients with hemiplegia compared to healthy subjects. Weight bearing and EMG activity of the quadriceps femoris on the paretic or nondominant side significantly increased during a knee flexion of 30° with under the foot asymmetry and foot lifting positions compared with the parallel foot position.

CONCLUSION

Isolating the paretic limb using the asymmetric foot positions and lifting of the foot during squats might help patients with hemiplegia to improve weight-bearing and achieve greater activation of the quadriceps muscle in the paretic limb.

Immediate and short-term effects of wearing a single textured insole on symmetry of stance and gait in healthy adults

Asymmetry of standing balance and gait are common in individuals with neurological or musculoskeletal disorders and achieving symmetrical stance and gait is an important goal of rehabilitation. The aim of the study was to investigate if asymmetry of stance and gait observed immediately after the start of using a single textured insole remains during longer use of the insole. Ten young healthy adults walked in two different conditions: with a textured insole positioned in the left shoe or without the insole. Weight bearing, gait, and perceived level of discomfort were evaluated before using a textured insole, immediately after being provided with the insole, and after walking for 10min with the insole. The center of pressure (COP) trajectory was calculated for the right and left foot in the insole and no-insole conditions. Asymmetry of stance and gait was present immediately after the start of using a textured insole (p<0.05) but was not evident after 10min of wearing the insole. The COP trajectory of the right foot after being provided with the left insole was significantly greater compared with walking with no insole (p<0.05). Gait velocity, cadence, and the COP trajectory of the left foot were not affected by the use of the insole. The outcome of the study provides a background for the investigation of the effect of using a textural insole in gait rehabilitation.

Randomized comparison trial of gait training with and without compelled weight-shift therapy in individuals with chronic stroke

Objective:

To compare the effects of gait training combined with compelled weight-shift therapy and gait training alone on velocity and gait symmetry in patients with chronic stroke.

Design:

Single-blind randomized controlled trial.

Participants:

Patients ( N=28) with chronic stroke and stance asymmetry toward the non-paretic side.

Interventions:

Six weeks of gait training combined with compelled weight-shift therapy via a shoe lift applied under the non-paretic leg (experimental group, n=14) or gait training alone (control group, n=14).

Main measures:

Percentage of total body weight carried by the paretic limb, gait velocity and gait spatiotemporal symmetry ratios including step symmetry, stance symmetry, swing symmetry and overall temporal symmetry.

Results:

When comparing the two groups, weight bearing on the affected side increased more significantly in experimental group than in control group (40.14±3.77, 38.28±4.06) after the end of treatment and also after a three-month follow-up (44.42±3.5, 38.5±3.77) (P<0.05). Among the experimental and control groups, there were no significant differences of gait velocity (cm/s) after six weeks of treatment (49.82±16.82, 42.66±18.75) and also after a three-month follow-up (50.94±16.27, 41.66±17.58) ( P>0.05). There were no significant differences of gait spatiotemporal symmetry ratios including step symmetry, stance symmetry, swing symmetry and overall temporal symmetry between the two groups after six weeks of treatment and also at three-month follow-up ( P>0.05).

Conclusions:

This study did not confirm that the effect of gait training combined with compelled body weight shift therapy was better than gait training alone on improving velocity and gait symmetry in patients with chronic stroke.

Locomotor Adaptation to an Asymmetric Force on the Human Pelvis Directed Along the Right Leg

In this work, we study locomotor adaptation in healthy adults when an asymmetric force vector is applied to the pelvis directed along the right leg. A cable-driven Active Tethered Pelvic Assist Device (A-TPAD) is used to apply an external force on the pelvis, specific to a subject's gait pattern. The force vector is intended to provide external weight bearing during walking and modify the durations of limb supports. The motivation is to use this paradigm to improve weight bearing and stance phase symmetry in individuals with hemiparesis. An experiment with nine healthy subjects was conducted. The results show significant changes in the gait kinematics and kinetics while the healthy subjects developed temporal and spatial asymmetry in gait pattern in response to the applied force vector. This was followed by aftereffects once the applied force vector was removed. The adaptation to the applied force resulted in asymmetry in stance phase timing and lower limb muscle activity. We believe this paradigm, when extended to individuals with hemiparesis, can show improvements in weight bearing capability with positive effects on gait symmetry and walking speed.

Repetitive sit-to-stand training with the step-foot position on the non-paretic side, and its effects on the balance and foot pressure of chronic stroke subjects

[Purpose] This study aimed to improve the asymmetrical weight-bearing ratio by applying repetitive sit-to-stand training methods that feature a step-foot position to the paretic-side foot of hemiplegic patients; it sought also to provide the information needed to apply weight-bearing and balance training to hemiplegic patients. [Subjects and Methods] The subjects were divided into two groups: a spontaneous group and a step group. They all performed repetitive sit-to-stand training five times per week for a total of six weeks. The Biodex Balance System, TUG, and 5XSST were used to measure the static and dynamic standing balance of each patient. A foot mat system was used to measure foot pressure. [Results] In the balance measurements, differences in the Overall index, Ant-post index, Med-lat index, Fall risk index, TUG, and 5XSST after training was significantly different between the two study groups. In evaluating foot pressure measurements, we found that the COP (Ant-post), Peak pressure: hind foot, and Contact area: hind foot measurements significantly differed between the groups after the training. [Conclusion] Repetitive sit-to-stand training that involves positioning the non-paretic leg upward can be considered a significant form of training that improves the symmetric posture adjustment and balance of hemiplegic patients following a stroke.

Effect of constrained weight shift on the static balance and muscle activation of stroke patients

[Purpose] The purpose of this study was to evaluate the effects of constrained weight shift induced by shoe lift beneath the unaffected lower extremity, on balance functions and electromyography of the affected lower extremity of stroke patients. [Subjects and Methods] Twelve patients with unilateral stroke were recruited as volunteers for this study. The subjects were repeatedly measured in a randomized order under three conditions: no-shoe lift, and shoe lifts of 5 mm and 10 mm heights beneath the unaffected lower extremity. [Results] Standing with a 10 mm shoe lift for the unaffected lower extremity decreased the mean velocity of mediolateral sway compared to no-shoe lift. Regarding the velocity of anteroposterior sway, standing with 5 mm and 10 mm shoe lifts decreased the mean velocity of anteroposterior sway. The muscle activation of the affected lower extremity was not significantly different among the no-shoe lift, 5 mm shoe lift and 10 mm shoe lift conditions; however, the muscle activities of the rectus femoris, biceps femoris, tibialis anterior, and medial gastrocnemius of the affected lower extremity progressively improved with increasing height of the shoe lift. [Conclusion] A constrained weight shift to the affected side elicited by a shoe insole of 10 mm height on the unaffected side can improve the static standing balance of stroke patients, and it resulted in 14–24% increases in the muscle activities of the affected leg.

Perception of gait patterns that deviate from normal and symmetric biped locomotion

This study examines the range of gait patterns that are perceived as healthy and human-like with the goal of understanding how much asymmetry is allowable in a gait pattern before other people start to notice a gait impairment. Specifically, this study explores if certain abnormal walking patterns can be dismissed as unimpaired or not uncanny. Altering gait biomechanics is generally done in the fields of prosthetics and rehabilitation, however the perception of gait is often neglected. Although a certain gait can be functional, it may not be considered as normal by observers. On the other hand, an abnormally perceived gait may be more practical or necessary in some situations, such as limping after an injury or stroke and when wearing a prosthesis. This research will help to find the balance between the form and function of gait. Gait patterns are synthetically created using a passive dynamic walker (PDW) model that allows gait patterns to be systematically changed without the confounding influence from human sensorimotor feedback during walking. This standardized method allows the perception of specific changes in gait to be studied. The PDW model was used to produce walking patterns that showed a degree of abnormality in gait cadence, knee height, step length, and swing time created by changing the foot roll-over-shape, knee damping, knee location, and leg masses. The gait patterns were shown to participants who rated them according to separate scales of impairment and uncanniness. The results indicate that some pathological and asymmetric gait patterns are perceived as unimpaired and normal. Step time and step length asymmetries less than 5%, small knee location differences, and gait cadence changes of 25% do not result in a change in perception. The results also show that the parameters of a pathologically or uncanny perceived gait can be beneficially altered by increasing other independent parameters, in some sense masking the initial pathology.

Effect of forced use of the lower extremity on gait performance and mobility of post-acute stroke patients

[Purpose] The purpose of this study was to investigate the effects of a forced-use training program on gait, mobility and quality of life of post-acute stroke patients. [Subjects] Twenty-one individuals with unilateral stroke participated in this study. All participants had suffered from first-ever stroke with time since onset of at least 3 months. [Methods] A single-blinded, non-equivalent, pre-post controlled design with 1-month follow-up was adopted. Participants received either a forced-use or a conventional physical therapy program for 2 weeks. The main outcomes assessed were preferred and fastest walking velocities, spatial and temporal symmetry indexes of gait, the timed up and go test, the Rivermead Mobility Index, and the Stroke-Specific Quality of Life Scale (Taiwan version). [Results] Forced-use training induced greater improvements in gait and mobility than conventional physical therapy. In addition, compared to pre-training, patients in the conventional physical therapy group walked faster but more asymmetrically after training. However, neither program effectively improved in-hospital quality of life. [Conclusion] The forced-use approach can be successfully applied to the lower extremities of stroke patients to improve mobility, walking speeds and symmetry of gait.

Kinetic Shapes: Analysis, Verification, and Applications

A circular shape placed on an incline will roll; similarly, an irregularly shaped object, such as the Archimedean spiral, will roll on a flat surface when a force is applied to its axle. This rolling is dependent on the specific shape and the applied force (magnitude and location). In this paper, we derive formulas that define the behavior of irregular 2D and 3D shapes on a flat plane when a weight is applied to the shape's axle. These kinetic shape (KS) formulas also define and predict shapes that exert given ground reaction forces when a known weight is applied at the axle rotation point. Three 2D KS design examples are physically verified statically with good correlation to predicted values. Motion simulations of unrestrained 2D KS yielded expected results in shape dynamics and self-stabilization. We also put forth practical application ideas and research for 2D and 3D KS such as in robotics and gait rehabilitation.

The effect of lateral or medial wedges on control of postural sway in standing

The objective of this study was to evaluate the effects of lateral and medial wedges on postural sway. Twenty healthy volunteers (mean age range of 28.45±3.34) participated in the study. They stood barefoot with eyes open or closed on each of the three surfaces: 10° lateral wedges, 10° medial wedges, and no wedges. Force platform data were collected and the mean and root mean square (RMS) distance, range, and velocity and the mean frequency of the center of pressure (COP) were calculated in the anterior-posterior (AP) and medial-lateral (ML) directions. Standing on both lateral and medial wedges was associated with improved postural stability seen through the decreased mean and RMS distance of COP displacement in ML direction. The results of this study suggest that standing on either lateral or medial wedges might enhance postural control in standing.

Compelled body weight shift approach in rehabilitation of individuals with chronic stroke

PURPOSE

This study was designed to evaluate the effectiveness of the compelled body weight shift (CBWS) therapy approach in the rehabilitation of individuals with chronic stroke. CBWS involves a forced shift of body weight toward a person's affected side by means of a shoe insert that establishes a lift of the nonaffected lower extremity.

METHOD

Eighteen individuals with chronic, unilateral stroke (mean age 57.7 ± 11.9 years, with a range of 35-75 years; mean time since stroke 6.7 ± 3.9 years, with a range of 1.1-14.1 years) who showed asymmetrical stance were randomly divided into 2 groups: the experimental group received 6 weeks of physical therapy combined with CBWS therapy, and the control group received only physical therapy. Both groups underwent a battery of identical tests (Fugl-Meyer Assessment, Berg Balance Scale, weight bearing, and gait velocity) before the start of the rehabilitation intervention, following its completion, and 3 months after the end of therapy.

RESULTS

After the intervention, weight bearing on the affected side (measured with the Balance Master) increased in the experimental group to a larger degree compared to the control group (9.7% vs 6.4%). Similarly, gait velocity increased 10.5% in the experimental group compared to the control group. Improvements in weight bearing and gait velocity were maintained in the experimental group after the 3-month retention period.

CONCLUSION

The study outcome revealed that a 6-week intervention involving CBWS therapy could result in a long-lasting improvement of the symmetry of weight bearing and velocity of gait in individuals with chronic stroke.

Compelled Body Weight Shift Technique to Facilitate Rehabilitation of Individuals with Acute Stroke

BACKGROUND

The study evaluates the effectiveness of Compelled Body Weight Shift (CBWS) approach in the rehabilitation of individuals with stroke. CBWS involves a forced shift of body weight towards a person's affected side by means of a shoe insert that establishes a lift of the nonaffected lower extremity.

METHODS

Eleven patients with acute stroke were randomly assigned to experimental and control groups. The experimental group received a two-week conventional physical therapy combined with CBWS and the control group received only a two-week conventional therapy. Weight bearing, Gait velocity, Berg's Balance, and Fugl-Meyer's Scores were recorded before and after the intervention.

RESULTS

Weight bearing on the affected side increased in the experimental group and decreased in the control group. The increase in gait velocity with treatment was significant in both the groups (P < 0.05). However, experimental group (P = 0.01) demonstrated larger improvements in gait velocity compared to the control group (P = 0.002). Berg Balance and Fugl-Meyer scores increased for both the groups.

CONCLUSION

The implementation of a two-week intervention with CBWS resulted in the improvement in weight bearing and gait velocity of individuals with acute stroke. The present preliminary study suggests that CBWS technique could be implemented as an adjunct to conventional rehabilitation program for individuals with acute stroke.

Comparação entre medidas de descarga, simetria e transferência de peso em indivíduos com e sem hemiparesia

Avaliação da Simetria e Transferência de Peso (ASTP) foi indicada para se fazer associação entre simetria e atividades funcionais nas hemiparesias, apontando simétricos como mais capacitados. Contudo, tais relações não são claras e divergem com evidências que sugerem assimetrias como estratégias funcionais. Assim, objetivou-se verificar se as medidas subjetivamente determinadas pela ASTP concordam com medidas calculas pela descarga de peso entre os pés. Realizou-se estudo observacional do tipo transversal para amostra de sujeitos com hemiparesia (n=20) pareados por idade e gênero a controles (n=20). Os participantes submeteram-se a procedimentos para obtenção de escore determinado pela ASTP e para cálculo da razão de simetria (RS) na descarga de peso entre os pés obtido por meio de duas balanças digitais. Os resultados obtidos pela ASTP identificaram apenas um sujeito com hemiparesia apresentando simetria, dentre os quatro sujeitos identificados pela RS como simétricos. Ainda, a ASTP não diferenciou assimetrias com sobrecarga para o lado afetado e apresentou correlação significativa somente quando os escores foram analisados com os valores de RS<1(sobrecarga para o lado não afetado). Conclui-se que a ASTP não foi concordante em identificar sujeitos hemiparéticos com descarga de peso compatível com simetria. Ainda, não identificou sobrecargas para o lado afetado que poderia conduzir a análises equivocadas da associação entre simetria e desempenho funcional.

Foot posture after stroke: frequency, nature and clinical significance

Objectives: Clinical convention suggests that foot posture and movements are adversely affected by stroke and cause walking difficulties but there is little objective data to support or refute these beliefs. This study explores static foot posture in people with stroke and their relationship to weakness and spasticity and walking limitations.

Design: Cross-sectional survey.

Setting: Stroke services and support groups of two acute hospitals.

Subjects: Seventy-two stroke survivors with mobility limitations.

Main measures: Foot Posture Index; Demographics; Motricity Index (weakness); modified Ashworth Scale (spasticity); Walking Handicap Scale (walking limitations).

Results: About one-third of participants had abnormal foot posture on the weak side, which was associated with walking limitations. Most (70%) had a symmetrical foot posture with similar frequencies of supination (13%) and pronation (16%) abnormalities. There was no relationship between foot posture and weakness and spasticity; age was the only independent predictor of foot posture abnormalities.

Conclusions: A minority of people with stroke had abnormal or asymmetrical foot posture and equal numbers suffered pronation and supination abnormalities; these findings challenge the beliefs that underpin the clinical management of stroke-related foot problems.

Efficacy of an insole shoe wedge and augmented pressure sensor for gait training in individuals with stroke: a randomized controlled trial

Objective: To determine whether external feedback to promote symmetrical weight distribution during standing and walking would improve gait performance and balance in people with stroke.

Design: Randomized, controlled, assessor-blinded trial.

Setting: Rehabilitation unit and physical therapy department.

Subjects: Thirty-five individuals with stroke (mean (SD) age = 53.0 (9.3) years) were randomly assigned to an experimental ( n = 17) or control group ( n = 18). Time post stroke was less than six months for most subjects ( n = 27, 77%).

Interventions: Subjects participated in 15 rehabilitation sessions including 30 minutes of gait retraining per session. During gait retraining, the experimental group used an insole shoe wedge and sensors set-up (I-ShoWS) while the control group received a conventional programme. The I-ShoWS set-up consisted of a wedge insole and a footswitch for the non-paretic leg and a pressure sensor on the paretic leg.

Outcome measures: Gait speed, step length and single support time asymmetry ratio, balance and amount of load on paretic leg during stance were evaluated twice: one day before and after training.

Results: The experimental group demonstrated significant increase in standing and gait symmetry compared with the control group ( P < 0.05). They demonstrated 3 times greater improvement in gait speed than the control group ( P = 0.02). Balance improvement was significantly greater for the experimental than for the control group ( P < 0.05).

Conclusion: Gait retraining using the I-ShoWS set-up was more effective in restoration of gait speed, standing and walking symmetry and balance than a conventional treatment programme. These results indicate the benefit of implementing feedback during gait retraining.

Early observations of the effects of lateral wedge orthoses on lower limb muscle length and potential for exacerbating spasticity

Lateral wedge orthoses are often prescribed to correct varus deformity after stroke. Spasticity is implicated in varus deformity and is caused by velocity-related muscle length changes, so a lateral wedge may affect spasticity by manipulating foot and ankle kinematics which, in turn, may alter the length of these muscles. We sought to test this theory in healthy participants. Eight volunteers walked with no wedge and with lateral wedges of 5 and 8.5 degrees in both shoes. Qualysis motion capture system collected kinematic data and SIMM musculoskeletal modeling software calculated muscle tendon length of plantarflexor and peroneal muscle groups using 3-D ankle and knee joint angle data. The wedges increased ankle eversion (p < 0.0001) and total excursion of tibialis posterior, peroneus longus and brevis by 13-29% (p < 0.05). Muscle length of peroneus longus and brevis increased by <1% (p < 0.005). Potentially clinical meaningful effects were found for tibialis posterior (15%), peroneus brevis (23%) and peroneus tertius (13%). Further research is required to be conclusive and to explore the effects of lateral wedge orthoses in patients with stroke. If such changes are seen in people with stroke, a change in orthotic prescription practice could be indicated as lateral wedge orthoses may exacerbate spasticity.

Asymmetric leg loading during sit-to-stand, walking and quiet standing in patients after unilateral total hip replacement surgery

BACKGROUND

Asymmetric limb loading persists well after unilateral total hip replacement surgery and represents a risk of the development of osteoarthritis in the non-operated leg. Here we studied bilateral limb loading in hip arthroplasty patients for a variety of everyday activities.

METHODS

Twenty-seven patients and 27 healthy age-matched control subjects participated in the study. They were asked to stand up from a chair, to stand quietly, to perform isometric maximal voluntary contractions and to walk along a 10 m path at a natural and fast speed. Two force platforms measured vertical forces under each foot during quiet standing and sit-to-stand maneuver. Temporal variables of gait were measured using footswitches.

FINDINGS

In all tasks patients tended to preferentially load the non-operated limb, though the amount of asymmetry depended on the task being most prominent during standing up (inter-limb weight bearing difference exceeded 20%, independent of speed or visual conditions). In contrast, when performing maximal voluntary contractions, or during walking and quiet standing, the inter-limb difference in the maximal force production, stance/swing phase durations or weight bearing was typically less than 10%.

INTERPRETATION

The results suggest that the amount of asymmetry might not be necessarily the same for different tasks. Asymmetric leg loading in patients can be critical during sit-to-stand maneuver in comparison with quiet standing and walking, and visual information seems to play only a minor role in the control of the weight-bearing ability. The proposed asymmetry indices might be clinically significant for development of post-surgical rehabilitation.

The effect of asymmetry of posture on anticipatory postural adjustments

The study investigates the effect of body asymmetry on anticipatory postural adjustments (APAs). Subjects performed a task involving a standard load release induced by a shoulder abduction movement while standing symmetrically or in an asymmetrical stance with either their right or left leg in 45 degrees of external rotation. EMG activities of trunk and leg muscles were recorded during the postural perturbation and were quantified within the time intervals typical of APAs. Anticipatory postural adjustments were observed in all experimental conditions. It was found that asymmetrical body positioning was associated with significant asymmetrical patterns of APAs seen in the right and left distal muscles. These APA asymmetries were dependant upon the side in which the body asymmetry was induced: reduced APAs were observed in the leg muscles on the side of leg rotation, while increased APAs were seen in the muscles on the contralateral side. These findings stress the important role that body asymmetries play in the control of upright posture.

A review of standing balance recovery from stroke

Recently, interest in the mechanisms underlying balance recovery following stroke has grown, because insight into these mechanisms is necessary to develop effective rehabilitation strategies for different types of stroke. Studies dealing with the recovery of standing balance from stroke are, however, limited to rehabilitation inpatients with a unilateral supratentorial brain infarction or haemorrhage. In most of these patients, stance stability improves in both planes as well as the ability to compensate for external and internal body perturbations and to control posture voluntarily. Although there is evidence of true physiological recovery of paretic leg muscle functions in postural control, particularly during the first three months post-stroke, substantial balance recovery also occurs in patients when there are no clear signs of improved support functions or equilibrium reactions exerted through the paretic leg. This type of recovery probably takes much longer than 3 months. Apparently, mechanisms other than the restoration of paretic leg muscle functions may determine the standing balance recovery in patients after severe stroke. No information is available about the role of stepping responses as an alternative to equilibrium reactions for restoring the ability to maintain upright stance after stroke. The finding that brain lesions involving particularly the parieto-temporal junction are associated with poor postural control, suggests that normal sensory integration is critical for balance recovery. Despite a considerable number of intervention studies, no definitive conclusions can be drawn about the best approach to facilitate the natural recovery of standing balance following stroke.