Effect of stiffness-optimized ankle foot orthoses on joint work in adults with neuromuscular diseases is related to severity of push-off deficits

BACKGROUND

People with plantar flexor weakness generate less ankle push-off work during walking, resulting in inefficient proximal joint compensations. To increase push-off work, spring-like ankle foot orthoses (AFOs) can be provided. However, whether and in which patients AFOs increase push-off work and reduce compensatory hip and knee work is unknown.

METHODS

In 18 people with bilateral plantar flexor weakness, we performed a 3D gait analysis at comfortable walking speed with shoes-only and with AFOs of which the stiffness was optimized. To account for walking speed differences between conditions, we compared relative joint work of the hip, knee and ankle joint. The relationships between relative work generated with shoes-only and changes in joint work with AFO were tested with Pearson correlations.

RESULTS

No differences in relative ankle, knee and hip work over the gait cycle were found between shoes-only and AFO (p>0.499). Percentage of total ankle work generated during pre-swing increased with the AFO (AFO: 85.3±9.1% vs Shoes: 72.4±27.1%, p=0.026). At the hip, the AFO reduced relative work in pre-swing (AFO: 31.9±7.4% vs Shoes: 34.1±10.4%, p=0.038) and increased in loading response (AFO: 18.0±11.0% vs Shoes: 11.9±9.8%, p=0.022). Ankle work with shoes-only was inversely correlated with an increase in ankle work with AFO (r=-0.839, p<0.001) and this increase correlated with reduction in hip work with AFO (r=-0.650, p=0.004).

DISCUSSION

Although stiffness-optimized AFOs did not alter the work distribution across the ankle, knee and hip joint compared to shoes-only walking, relative more ankle work was generated during push-off, causing a shift in hip work from pre-swing to loading response. Furthermore, larger ankle push-off deficits when walking with shoes-only were related with an increase in ankle work with AFO and reduction in compensatory hip work, indicating that more severely affected individuals benefit more from the energy storing-and-releasing capacity of AFOs.

Effects of ankle-foot orthosis with dorsiflexion resistance on the quasi-joint stiffness of the ankle joint and spatial asymmetry during gait in patients with hemiparesis

BACKGROUND

Reduced ankle quasi-joint stiffness affects propulsion in the paretic side of patients with hemiparesis, contributing to gait asymmetry. We investigated whether the use of an ankle-foot orthosis with dorsiflexion resistance to compensate for reduced stiffness would increase quasi-joint stiffness and spatiotemporal symmetry in patients with hemiparesis.

METHODS

Seventeen patients walked along a 7-m walkway in both ankle-foot orthosis with dorsiflexion resistance and control (i.e., ankle-foot orthosis) conditions. Dorsiflexion resistance by spring and cam was set to increase linearly from zero-degree ankle dorsiflexion. Gait data were analyzed using a three-dimensional motion analysis system.

FINDINGS

Ankle-foot orthosis with dorsiflexion resistance significantly increased the quasi-joint stiffness in the early and middle stance phase (P = 0.028 and 0.040). Furthermore, although ankle power generation in the ankle-foot orthosis with dorsiflexion resistance condition was significantly lower than in the control condition (P = 0.003), step length symmetry significantly increased in the ankle-foot orthosis with dorsiflexion resistance condition (P = 0.016). There was no significant difference in swing time ratio between conditions.

INTERPRETATION

Applying dorsiflexion resistance in the paretic stance phase increased quasi-joint stiffness but did not lead to an increase in ankle power generation. On the other hand, applying dorsiflexion resistance also resulted in a more symmetrical step length, even though the ankle joint power generation on the paretic side did not increase as expected. Future research should explore whether modifying the magnitude and timing of dorsiflexion resistance, considering the biomechanical characteristics of each patients' ankle joint during gait, enhances ankle joint power generation.

Optimizing 3D printed ankle-foot orthoses for patients with stroke: Importance of effective elastic modulus and finite element simulation

Patients with stroke often use ankle-foot orthoses (AFOs) for gait improvement. 3D printing technology has become a popular tool in recent years for the production of AFOs due to its strengths on customization and rapid manufacturing. However, the porosity of the 3D printed materials affects the kinetic features of these orthoses, leading to its lower-strength than solid ones. The effective elastic modulus of 3D printed material was measured following standard test method to obtain the kinetic features precisely in a finite element simulation. This study demonstrated that the porosity of 3D printed samples using 100% fill density was 11% for PLA and 16% for Nylon. As a result, their effective elastic modulus was reduced to 1/3 and 1/12 of fully solid objects, respectively, leading to a lower stiffness of 3D printed orthoses. A fatigue testing platform was built to verify our finite element model, and the findings of the fatigue test were consistent with the analysis of the finite element model. Further, our AFO has been proven to have a lifespan exceeding 200 thousand steps. Our study highlights the significance of determining the actual porosity of 3D printed samples by calculating the effective elastic modulus, which leads to a more precise finite element simulation and enables reliable prediction of the kinetic features of the AFO. Overall, this study provides valuable insights into the production and optimization of 3D printed AFOs for patients with stroke.

In-silico simulations to study the effects of ankle-joint misalignments in Ankle-Foot-Orthoses during level walking

Exoskeletons and orthotic devices are commonly used in physical rehabilitation. However, these devices, fitting intimately with the human body, often lead to skin-related issues amongst users. Misalignments between orthotic and anatomical joints cause relative sliding motion between the limb and orthosis and also cause pressure points on the limb, which may contribute to these skin problems. This research quantifies the effects of sagittal plane ankle-joint misalignments for an ankle-foot orthosis (AFO) user during walking. A 2D mathematical model that simulates the effects of sagittal plane ankle-joint misalignments in terms of relative motion between the limb and the orthosis was developed using MATLAB software. The orthotic ankle-joint was systematically misaligned against the anatomical ankle-joint to generate various misalignment conditions. Published gait data of 5 healthy subjects was used to generate walking kinematics which was then superimposed with an articulated AFO. The simulations showed that Anterior-Posterior misalignments resulted in greater pistoning motion than Proximal-Distal misalignments. Combined misalignments (Posterior-Distal, Anterior-Proximal, Posterior-Proximal, and Anterior-Distal) resulted in higher overall relative motions between the limb and AFO. The model also predicted pressure points on the shank and foot caused by misalignments. This study demonstrates that misaligned ankle-joints in AFOs lead to relative sliding motion and pressure points during walking.

Perspectives on ankle-foot technology for improving gait performance of children with Cerebral Palsy in daily-life: requirements, needs and wishes

BACKGROUND

Ankle-foot orthoses (AFOs) are extensively used as a primary management method to assist ambulation of children with Cerebral Palsy (CP). However, there are certain barriers that hinder their prescription as well as their use as a mobility device in all kinds of daily-life activities. This exploratory research attempts to further understand the existing limitations of current AFOs to promote a better personalization of new design solutions.

METHODS

Stakeholders' (professionals in CP and end-users with CP) perspectives on AFO technology were collected by two online surveys. Respondents evaluated the limitations of current assistive solutions and assessment methods, provided their expectations for a new AFO design, and analyzed the importance of different design features and metrics to enrich the gait performance of these patients in daily-life. Quantitative responses were rated and compared with respect to their perceived importance. Qualitative responses were classified into themes by using content analysis.

RESULTS

130 survey responses from ten countries were analyzed, 94 from professionals and 36 from end-users with CP. The most highly rated design features by both stakeholder groups were the comfort and the ease of putting on and taking off the assistive device. In general, professionals preferred new features to enrich the independence of the patient by improving gait at functional levels. End-users also considered their social acceptance and participation. Health care professionals reported a lack of confidence concerning decision-making about AFO prescription. To some degree, this may be due to the reported inconsistent understanding of the type of assistance required for each pathological gait. Thus, they indicated that more information about patients' day-to-day walking performance would be beneficial to assess patients' capabilities.

CONCLUSION

This study emphasizes the importance of developing new approaches to assess and treat CP gait in daily-life situations. The stakeholders' needs and criteria reported here may serve as insights for the design of future assistive devices and for the follow-up monitoring of these patients.

A triple compound pendulum model to analyse the effect of an ankle-foot orthosis on swing phase kinematics

Powered ankle-foot orthoses can be utilised to overcome gait abnormalities such as foot drop; however, normal gait is rarely restored with compensatory gait patterns arising and prevalence of gait asymmetry. Therefore, this study aims to determine the effect of orthosis mass and mass distribution on the swing phase of gait, to understand residual gait asymmetry with orthosis use. Using a triple compound pendulum model, which accounts for mass distribution of the limb and orthosis, the swing phase of gait is simulated in terms of natural dynamics and the effect of an orthosis on kinematic parameters is quantitatively determined. It was found that additional mass causes faster and shorter steps on the affected side due to rapid knee extension and reduced hip flexion, with particular actuator positions and natural cadence causing varying severity of these effects. Our study suggests that this model could be used as a preliminary design tool to identify subject specific optimum orthosis mass distribution of a powered ankle-foot orthosis, without the need for motion data or experimental trials. This optimisation intends to more accurately mimic natural swing phase kinematics, consequently allowing for the reduction in severity of gait asymmetry and the potential to improve rehabilitative outcomes.

The influence of ankle-foot orthoses on gait pathology in children with cerebral palsy: A retrospective study

BACKGROUND

Ankle-foot orthoses (AFOs) are frequently prescribed in children with cerebral palsy (CP) to improve their gait. Due to the heterogeneous nature of CP and contradictions among previous studies, it is important to evaluate the AFO-specific effects, as well as explore their effects on different gait patterns.

RESEARCH QUESTIONS

a) What are the prevalence and specific features of AFOs in children with CP? b) How do AFOs affect gait pathology in children with CP? c) What are the pattern-specific effects of AFOs in children with CP?

METHODS

A group of 170 patients with CP underwent a three-dimensional gait analysis with and without AFOs (either carbon fiber, rigid, flexible or hinged). The gait profile score, the gait variable scores of the hip, knee and ankle joints, non-dimensional step length and walking speed were used as outcome measures. The AFO-specific effects on the kinematic and kinetic waveforms were investigated using statistical non-parametric mapping (SnPM). Effects were considered relevant when the minimal clinically important difference (MCID) or the standard errors of measurement, for the parameters or the waveforms respectively, were exceeded.

RESULTS

Rigid AFOs were prescribed for more than 80 % of the children. Significant beneficial effects were observed for non-dimensional step length and walking speed. Most changes in gait indices were not considered relevant. The SnPM-analyses on the total group and specific gait patterns revealed that walking with AFOs improved the kinematic and kinetic waveforms. These effects were relevant, and were most obvious for crouch, apparent equinus and the total group.

SIGNIFICANCE

The use of AFOs improves gait, whether we inspect a total -and thus heterogeneous- group or focus on specific gait patterns. However, focussing on specific parameters (i.e. general gait indices) does not provide a full picture of the AFO-effects.

Orthotic Research Initiative for Outcomes aNalysis (ORION I): predictors of PROMIS PF for stroke survivors seeking orthotic intervention

PURPOSE

Ankle-foot orthoses (AFOs) are used to improve physical performance measures of physical function (PF) post-stroke; however, the perception of improved PF of this population has not been described. The purpose of this study was to identify the predictors of self-reported PF of individuals seeking orthotic intervention post-stroke.

MATERIALS AND METHODS

A retrospective analysis of 237 patients at a nationwide orthotic services provider in the United States was conducted to characterize PF using the Patient-Reported Outcome Measures Information System®. A backward stepwise multiple regression was conducted to identify demographic characteristics predictive of self-reported PF.

RESULTS

The mean T-score of PF of the sample was 30.8 (±6.5), two standard deviations below the US general population mean, indicating significant impairment. The regression model explained approximately 15% (R = 0.411) of the variance in PF of the sample. Self-reported PF was worse for individuals requiring more supportive assistive devices (β = 0.270, p = 0.001), those with more recent ankle problems (β = -0.167, p = 0.035), and those with greater living assistance (β = -0.139, p = 0.089).

CONCLUSIONS

These results improve understanding of the factors that contribute to impaired self-reported PF of stroke survivors in need of AFO intervention.Implications for rehabilitationAnkle-foot orthoses (AFOs) are often used to improve physical performance measures of physical performance (PF) during stroke rehabilitation.Our data indicate that the self-reported PF of AFO users is severely impaired.Level of assistance, time since ankle and foot problems began, and living assistance status are important clinical characteristics to consider when planning AFO intervention for this population.

A comparison between laterally wedged insoles and ankle-foot orthoses for the treatment of medial osteoarthritis of the knee: A randomized cross-over trial

Objective:

To compare biomechanical and clinical outcome of laterally wedged insoles (LWI) and an ankle-foot orthosis (AFO) in patients with medial knee osteoarthritis.

Design:

Single-centre, block-randomized, cross-over controlled trial.

Setting:

Outpatient clinic.

Subjects:

About 39 patients with symptomatic medial knee osteoarthritis.

Interventions:

Patients started with either LWI or AFO, determined randomly, and six weeks later changed to the alternative.

Main measures:

Change in the 1st maximum of external knee adduction moment (eKAM) was assessed with gait analysis. Additional outcomes were other kinetic and kinematic changes and the patient-reported outcomes EQ-5D-5L, Oxford Knee Score (OKS), American Knee Society Clinical Rating System (AKSS), Hannover Functional Ability Questionnaire – Osteoarthritis and knee pain.

Results:

Mean age (SD) of the study population was 58 (8) years, mean BMI 30 (5). Both aids significantly improved OKS (LWI P = 0.003, AFO P = 0.001), AKSS Knee Score (LWI P = 0.01, AFO P = 0.004) and EQ-5D-5L Index (LWI P = 0.001, AFO P = 0.002). AFO reduced the 1st maximum of eKAM by 18% (P < 0.001). The LWI reduced both maxima by 6% (P = 0.02, P = 0.03). Both AFO and LWI reduced the knee adduction angular impulse (KAAI) by 11% (P < 0.001) and 5% (P = 0.05) respectively. The eKAM (1st maximum) and KAAI reduction was significantly larger with AFO than with LWI (P = 0.001, P = 0.004).

Conclusions:

AFO reduces medial knee load more than LWI. Nevertheless, no clinical superiority of either of the two aids could be shown.

Impact of a dynamic ankle orthosis on acute pain and function in patients with mechanical foot and ankle pain

BACKGROUND

Over two million Americans visit the doctor each year for foot and ankle pain stemming from a degenerative condition or injury. Ankle-foot orthoses can effectively manage symptoms, but traditional designs have limitations. This study investigates the acute impact of a novel "dynamic ankle-foot orthosis" ("orthosis") in populations with mechanical pain (from motion or weight-bearing).

METHODS

With and without the brace, participants (n = 25) performed standing, over-ground level walking, treadmill level walking, stair ascent, stair descent, single leg hold, squat, and sitting. Instrumented insoles captured in-shoe vertical forces and a visual analog scale was used to assess pain levels during each activity. Subsequently, the self-perceived impact of the orthosis on the patient's symptoms and function was ranked on a scale from -10 (most worsened) to +10 (most improved).

FINDINGS

Peak in-shoe force was reduced during level and stair walking (P < 0.05). Average perceived pain was 1.2 to 1.6 points lower in the orthosis than the unbraced control for the active tasks. The majority of participants reported that the brace improved their symptoms (n = 19), while a smaller group reported that the brace did not affect their symptoms (n = 5), although average function scores were improved for both groups (+2.4 to +4.5). The group of individuals with improved symptoms included cases of osteoarthritis, tendon dysfunction, chronic pain, sprains, and nerve disorders.

INTERPRETATION

The orthosis effectively improved pain symptoms and improved the ability of impaired individuals to complete functional activities of daily living such as level walking and stair walking.

The prediction of need of using ankle-foot orthoses in stroke patients based on findings of a transcranial magnetic stimulation study

Ankle-foot orthoses (AFOs) are widely prescribed for stroke rehabilitation. We investigated the potential of transcranial magnetic stimulation (TMS) at an early stage, after stroke, to predict the need of using AFOs in stroke patients. We recruited 35 patients who could walk with intermittent support of one person or independently 3 months after onset of stroke. The patients included in the study were classified into two groups: a TMS (+) group (n = 10), in which motor-evoked potential (MEP) in the affected tibialis anterior (TA) was present, and a TMS (-) group (n = 25), in which the MEP in the affected TA was absent. Three months after the onset of stroke, we investigated whether patients were using AFOs or not. We also checked the motor function of the affected lower extremity using the Medical Research Council (MRC) scale. After 3 months of onset of stroke in the TMS (+) group, 4 patients (40%) were using an AFO during ambulation. In the TMS (-) group, 21 patients (84%) were using an AFO. The probability of using AFOs in the 2 groups were significantly different. Additionally, 3 months after the onset of stroke, the MRC scores of ankle dorsiflexor power, on the affected side, were significantly higher in the TMS (+) group. Early TMS evaluation of the corticospinal tract to the TA appears to be useful for predicting the need of using AFOs in stroke patients during the recovery phase.

Ankle-foot orthoses improve walking but do not reduce dual-task costs after stroke

BACKGROUND

Cognitive-motor interference, as measured by dual-task walking (performing a mental task while walking), affects many clinical populations. Ankle-foot orthoses (AFOs) are lower-leg splints prescribed to provide stability to the foot and ankle, as well as prevent foot drop, a gait deficit common after stroke. AFO use has been shown to improve gait parameters such as speed and step time, which are often negatively impacted by dual-task walking.

OBJECTIVES

Our objective was to establish whether AFOs could protect against cognitive-motor interference, as measured by dual-task walking, following post-stroke hemiplegia.

METHODS

A total of 21 individuals with post-stroke hemiplegia that use an AFO completed a dual-task walking paradigm in the form of a 2 (walking with vs. without a concurrent cognitive task) by 2 (walking with vs. without an AFO) repeated-measures design. Changes to both motor and cognitive performance were analyzed.

RESULTS

The results suggest that the use of an AFO improves gait overall in both single- and dual-task walking, particularly with respect to stride regularity, but there were no interactions to suggest that AFOs reduce the cognitive-motor dual-task costs themselves. A lack of differences in cognitive performance during dual-task walking with and without the AFO suggests that the AFO's benefit to motor performance cannot be attributed to task prioritization.

CONCLUSIONS

These data support the use of AFOs to improve certain gait parameters for post-stroke hemiplegia, but AFOs do not appear to protect against cognitive-motor interference during dual-task walking. Future research should pursue alternate therapeutics for ameliorating task-specific declines under cognitively demanding circumstances.

[Design and application of static progressive ankle foot orthosis]

The scar contracture of Achilles tendon in burn patients after operation is easy to cause " foot drop" , which leads to ankle dorsiflexion dysfunction. To solve this problem, the authors designed and made a static progressive ankle foot orthosis. The foot support part and the crus support part of the orthotic device are connected by rivets, and the distal end of the foot support part and the proximal end of the crus support part are pulled by the traction belt on both sides, gradually improving the ankle dorsiflexion function. This static progressive ankle foot orthosis is simple, practical, cost-effective, and worthy of clinical promotion.

Ankle foot orthoses in cerebral palsy: Effects of ankle stiffness on trunk kinematics, gait stability and energy cost of walking

In children with cerebral palsy (CP), rigid ventral shell ankle-foot orthoses (vAFOs) are often prescribed to reduce excessive knee flexion in stance and lower the energy cost of walking (ECW). However, how vAFOs affect ECW is a complex issue, as vAFOs may have an impact on lower limb biomechanics, upper body movements, and balance. Besides, the vAFO's biomechanical effect have been shown to be dependent on its stiffness around the ankle joint. We examined whether vAFO stiffness influences trunk movements and gait stability in CP, and whether there is a relationship between these factors and ECW. Fifteen children with spastic CP were prescribed vAFOs. Stiffness was varied into a rigid, stiff and flexible configuration. At baseline (shoes-only) and for each vAFO stiffness configuration, 3D-gait analyses and ECW-tests were performed. From the gait analyses, we derived trunk tilt, lateroflexion, and rotation range of motion (RoM) and the mediolateral and anteroposterior Margins of Stability (MoS) and their variability as measures of gait stability. With the ECW-test we determined the netEC. We found that wearing vAFOs significantly increased trunk lateroflexion (Wald χ2 = 33.7, p < 0.001), rotation RoM (Wald χ2 = 20.5, p < 0.001) and mediolateral gait instability (Wald χ2 = 10.4, p = 0.016). The extent of these effects partly depended on the stiffness of the vAFO. Significant relations between trunk movements, gait stability and ECW were found r = 0.57-0.81, p < 0.05), which indicates that trunk movements and gait stability should be taken into account when prescribing vAFOs to improve gait in children with CP walking with excessive knee flexion.

Stiffness modification of two ankle-foot orthosis types to optimize gait in individuals with non-spastic calf muscle weakness - a proof-of-concept study

Background

To reduce gait problems in individuals with non-spastic calf muscle weakness, spring-like ankle-foot orthoses (AFOs) are often applied, but they are not individually optimized to treatment outcome. The aim of this proof-of-concept study was to evaluate the effects of modifying the stiffness for two spring-like AFO types with shoes-only as reference on gait outcomes in three individuals with calf muscle weakness due to polio.

Methods

We assessed 3D gait biomechanics, walking speed and walking energy cost for shoes-only and five stiffness conditions of a dorsal-leaf-spring AFO and a spring-hinged AFO. Outcomes were compared between stiffness conditions in the two AFOs and three subjects.

Results

Maximum ankle dorsiflexion angle decreased with increasing stiffness in both AFOs (up to 6–8°) and all subjects. Maximum knee extension angle changed little between stiffness conditions, however different responses between the AFOs and subjects were observed compared to shoes-only. Walking speed remained unchanged across conditions. For walking energy cost, we found fairly large differences across stiffness conditions with both AFOs and between subjects (range 3–15%).

Conclusions

Modifying AFO stiffness in individuals with non-spastic calf muscle weakness resulted in substantial differences in ankle biomechanics and walking energy cost with no effect on speed. Our results provide proof-of-concept that individually optimizing AFO stiffness can clinically beneficially improve gait performance.

Electronic supplementary material

The online version of this article (10.1186/s13047-019-0348-8) contains supplementary material, which is available to authorized users.

A review on the orthotics and prosthetics and the potential of kenaf composites as alternative materials for ankle-foot orthosis

Since ancient Egypt, orthosis was generally made from wood and then later replaced with metal and leather which are either heavy, bulky, or thick decreasing comfort among the wearers. After the age of revolution, the manufacturing of products using plastics and carbon composites started to spread due to its low cost and form-fitting feature whereas carbon composite were due to its high strength/stiffness to weight ratio. Both plastic and carbon composite has been widely applied into medical devices such as the orthosis and prosthesis. However, carbon composite is also quite expensive, making it the less likely material to be used as an Ankle-Foot Orthosis (AFO) material whereas plastics has low strength. Kenaf composite has a high potential in replacing all the current materials due to its flexibility in controlling the strength to weight ratio properties, cost-effectiveness, abundance of raw materials, and biocompatibility. The aim of this review paper is to discuss on the possibility of using kenaf composite as an alternative material to fabricate orthotics and prosthetics. The discussion will be on the development of orthosis since ancient Egypt until current era, the existing AFO materials, the problems caused by these materials, and the possibility of using a Kenaf fiber composite as a replacement of the current materials. The results show that Kenaf composite has the potential to be used for fabricating an AFO due to its tensile strength which is almost similar to polypropylene's (PP) tensile strength, and the cheap raw material compared to other type of materials.

Major patterns of plantar flexion resistive torque during the gait cycle in healthy young adults wearing ankle foot orthoses with a plantar flexion stop: a pilot study

[Purpose] The Gait Judge System measures the plantar flexion resistive torque acting on the angle of the ankle joint, as well as the ankle joint itself, of the ankle-foot orthosis using a 1,000 Hz sampling frequency. This pilot study aimed to determine the characteristics of plantar flexion resistive torque acting on the double Klenzak ankle joint of the ankle-foot orthoses worn by healthy individuals. [Participants and Methods] Participants were eight healthy young adults (3 male, 5 female; mean age, 26.8 years old; mean height, 165 cm.; mean body weight, 56.3 kg). Plantar flexion resistive torques and angles of the ankle joint in gait cycles were measured with the Gait Judge System. Speed of gait was calculated using a ruler attached on the floor and the Gait Judge System video. We classified waveforms according to the existence of second peaks in the gait cycle. The correlations between parameters related to the plantar flexion resistive torque and the speed of gait were evaluated using Pearson's simple correlation analysis. [Results] The plantar flexion resistive torque showed two peaks: the first peak was at the loading response, measured at 17.4 Nm, and the second peak was at the pre-swing phase, measured at 10.9 Nm. However, the second peak was absent in three of the participants. The normalized second peak and the second peak/first peak ratio had a strong, positive correlation with the speed of gait. [Conclusion] The Gait Judge System revealed typical waveforms according to the parameters set in this study.

Surplus value of implanted peroneal functional electrical stimulation over ankle-foot orthosis for gait adaptability in people with foot drop after stroke

BACKGROUND

Implanted peroneal functional electrical stimulation (FES) is an effective alternative treatment to ankle-foot orthosis (AFO) in people with drop foot after stroke. With FES no constraints on ankle mobility are imposed which might particularly be exploited in challenging walking environments that require adaptations of the gait pattern to environmental disturbances.

RESEARCH QUESTION

Is gait adaptability, by means of the capacity to avoid sudden obstacles while walking on a treadmill, superior with implanted FES compared to AFO in people with drop foot after stroke?

METHODS

A 4-channel peroneal nerve stimulator (ActiGait®) was implanted in 22 persons with stroke (>6 months) who regularly used an AFO. Gait adaptability was tested with an obstacle avoidance task on an instrumented treadmill up to 26 weeks (n = 10) or 52 weeks (n = 12) after FES-system activation. At assessments, 30 trials, in which obstacles were suddenly dropped onto the treadmill in front of the paretic leg, were recorded with each device (FES / AFO). Trials were grouped by available response times (ART) and success rates were calculated. The effect of device, ART and follow up time on success rates was tested using generalized estimated equations. Nonparametric correlations were calculated to associate changes in success rates with clinimetrics.

RESULTS

Success rates of obstacle avoidance were higher when participants used their FES system compared to AFO (Δ4.7%, p = 0.03), which effect was largest for longest ARTs (Δ15%, p = 0.03). Participants with greater motor impairment of the paretic leg showed greater benefit from FES (r_s=-0.49, p = 0.04).

SIGNIFICANCE

FES has been found equally effective as AFO in improving walking speed of people with drop foot after stroke. We now present superior walking performance in a complex walking environment for implanted peroneal FES compared to AFO. These findings underline the importance of using gait assessments that require interplay with the environment, besides assessment of stationary walking, in community ambulators.

Effect of ankle-foot orthosis with a built-in spring on muscle activity during the sit-to-stand movement in healthy individuals

[Purpose] This study aimed to evaluate the influence of a newly developed ankle-foot orthosis with a built-in spring on the activity of lower limb muscles during the sit-to-stand movement. [Participants and Methods] This cross-sectional study recruited 20 male volunteers. The sit-to-stand movement (rising from a chair) was performed under three conditions: no ankle-foot orthosis (NA), ankle-foot orthosis with no spring (NS), and ankle-foot orthosis with a built-in spring (SP). Muscle activity during the sit-to-stand movement was measured using surface electrodes placed on the vastus medialis, tibialis anterior, medial gastrocnemius, and soleus muscles. Root mean square and integral value were calculated from the raw data, and statistical analysis was performed using SPSS version 24.0. [Results] The electromyography data of the vastus medialis, medial gastrocnemius, and soleus muscles showed a significant decrease in muscle activity in the SP condition, whereas the activity of the tibialis anterior muscle increased significantly in the SP condition compared to that in the NA and NS conditions. [Conclusion] Our data showed that the use of an ankle-foot orthosis with a built-in spring affected not only the muscle activity at the ankle joint but also the activity of the knee joint extensor muscle. It is possible that the control of the ankle joint motion affects movement above the knee joint; this finding may help development new physical therapy techniques. Further research is warranted in this regard.

Effects of a powered ankle-foot orthosis on perturbed standing balance

BACKGROUND

Lower extremity exoskeletons are mainly used to provide stepping support, while balancing is left to the user. Designing balance controllers is one of the biggest challenges in the development of exoskeletons. The goal of this study was to design and evaluate a balance controller for a powered ankle-foot orthosis and assess its effect on the standing balance of healthy subjects.

METHODS

We designed and implemented a balance controller based on the subject's body sway. This controller was compared to a simple virtual-ankle stiffness and a zero impedance controller. Ten healthy subjects wearing a powered ankle-foot orthosis had to maintain standing balance without stepping while receiving anteroposterior pushes. Center of mass kinematics, ankle torques and muscle activity of the lower legs were analyzed to assess the balance performance of the user and exoskeleton.

RESULTS

The different controllers did not significantly affect the center of mass responses. However, the body sway based controller resulted in a decrease of 29% in the biological ankle torque compared to the zero impedance controller and a decrease of 32% compared to the virtual-ankle stiffness. Furthermore, the soleus muscle activity of the left and right leg decreased on average with 8%, while the tibialis anterior muscle activity increased with 47% compared to zero impedance.

CONCLUSION

The body sway based controller generated human-like torque profiles, whereas the virtual-ankle stiffness did not. As a result, the powered ankle-foot orthosis with the body sway based controller was effective in assisting the healthy subjects in maintaining balance, although the improvements were not seen in the body sway response, but in the subjects' decreased biological ankle torques to counteract the perturbations. This decrease was a combined effect of decreased soleus muscle activity and increased tibialis anterior muscle activity.

Net ankle quasi-stiffness is influenced by walking speed but not age for older adult women

BACKGROUND

Insufficient plantar flexor resistance due to plantar flexor weakness, an impairment common in patient populations, causes substantial gait deficits. The bending stiffness of passive-dynamic ankle-foot orthoses (PD-AFOs) has the capacity to replace lost plantar flexor resistance. Many patients who are prescribed PD-AFOs are older adults. While PD-AFO bending stiffness should be customized for patients, a method to objectively prescribe this stiffness does not exist. Quantifying natural plantar flexor resistance during non-pathological gait could provide a reference value for objectively prescribing PD-AFO bending stiffness.

RESEARCH QUESTION

This study investigated the effect of age on plantar flexor resistance in 113 participants above the age of 65 years. We did so while also considering the confounding influence of gait speed, an aspect known to be reduced with old age.

METHODS

Ambulatory, community-dwelling older adult women (ages 65-91 years) with no current or recent lower-extremity injuries or surgeries underwent an instrumented gait analysis at a self-selected speed. Plantar flexor resistance was quantified via net ankle quasi-stiffness (NAS) defined as the slope of ankle joint moment-angle curve during late stance.

RESULTS

showed that NAS was not significantly influenced by age (r = -0.11, p = 0.12), and that the confounding factor of walking speed had a significant, positive relationship with NAS (r = 0.59, p < 0.001).

SIGNIFICANCE

By determining that gait speed, not age, is related to NAS in older adults, this study represents the initial step towards objectively prescribing PD-AFO bending stiffness to achieve a targeted gait speed for older adults with plantar flexor weakness.

Acute and mid-term (six-week) effects of an ankle-foot-orthosis on biomechanical parameters, clinical outcomes and physical activity in knee osteoarthritis patients with varus malalignment

BACKGROUND

Knee osteoarthritis (KOA) is a painful disease commonly caused by high loads on the articular cartilage. Orthotic interventions aim to reduce mechanical loading, thereby alleviating pain. Traditional orthotics appear effective, but high drop-out rates have been reported over prolonged periods.

RESEARCH QUESTION

The aim of this study was to examine the effect of a novel ankle-foot orthosis (AFO) on gait parameters, physical function and activity of KOA patients.

METHODS

29 clinically diagnosed KOA patients with varus malalignment wore an AFO for 6 weeks. Prior to and after the intervention period, 3D gait analysis, physical function tests and the KOOS questionnaire were administered. Physical activity was objectively assessed with accelerometers.

RESULTS

The AFO immediately reduced the first peak of the knee adduction moment (KAM) and the KAM impulse by 41% and 19%. The knee flexion moment (KFM) was increased by 48%. After six weeks, the first KAM peak and KAM impulse were decreased by 27% and 19% while using the AFO. The KFM was increased by 71%. Furthermore, patients completed the functional tests faster (1.4-2.6%). The KOOS scores decreased significantly. No significant differences were found in physical activity parameters.

SIGNIFICANCE

The six-week AFO application significantly reduced the KAM. The patients' physical function appeared improved; yet these improvements were only minor and therefore arguably clinically irrelevant. The KFM appeared to be negatively affected after six weeks, as were the scores on the KOOS subscales. In summary, even though the AFO reduced the KAM and improved physical function, the clinical benefit for KOA patients with varus malalignment after the 6-week AFO application is debatable.

A user-centered qualitative study on experiences with ankle-foot orthoses and suggestions for improved design

BACKGROUND

Improving ankle-foot orthosis design can best be done by implementing a user-centered approach.

OBJECTIVE

To provide insight into the ideas of ankle-foot orthosis users with flaccid ankle muscle paresis on the importance of activities and suggestions for an improved ankle-foot orthosis design.

STUDY DESIGN

A focus-group discussion with eight ankle-foot orthosis users (57 ± 5 years, 50% female).

METHODS

Main inclusion criteria were as follows: ⩾18 years, unable to stand on tip-toe and unable to lift toes. Main exclusion criterion was spasticity of lower extremity muscles. Transcribed data were coded according to the International Classification of Functioning, Disability and Health. Thematic analysis with inductive approach was chosen to order and interpret codes.

RESULTS

Ankle-foot orthosis users ranked walking the most important activity followed by sitting down/standing up from a chair. Their opinion was that ankle-foot orthoses facilitate walking and standing. Ankle-foot orthosis users suggested that an improved ankle-foot orthosis design should balance between stability and flexibility.

CONCLUSION

Current ankle-foot orthoses facilitate walking which was the most important activity according to ankle-foot orthosis users. An improved ankle-foot orthosis design should enable walking and should optimize between stability and flexibility dependent on the activity and the paresis severity. Clinical relevance Experienced users of ankle-foot orthosis agreed that matching ankle-foot orthosis functions to daily-life activities is a trade-off between stability and flexibility. An improved ankle-foot orthosis design should at least enable level walking.

A comparison of the initial orthotic effects of functional electrical stimulation and ankle-foot orthoses on the speed and oxygen cost of gait in multiple sclerosis

Background

Foot drop affects walking in people with multiple sclerosis (pwMS). This study compares the initial orthotic effects of two treatments for foot drop: ankle-foot orthoses (AFO) and functional electrical stimulation (FES), on the speed and oxygen cost of walking in MS.

Method and materials

Seventy-eight pwMS were randomised to receive AFO or FES (ODFS PACE (OML, Salisbury, UK)). Participants completed the 25-ft walk test (25ftWT) and 5-min self-selected walk test (5minSSWT), from which oxygen cost was determined, with and without their device. Between-, within- and sub-group analyses (based on baseline walking speed of <0.8 m/s (slow) or ≥0.8 m/s (fast)) were undertaken.

Results

No significant differences between baseline measures were observed. The AFO group walked significantly slower than the FES group (5minSSWT, p = 0.037, 0.11 m/s). The AFO group walked significantly slower with than without AFO (25ftWT, p = 0.037), particularly in the fast-walking group ( p = 0.011). The slow-walking FES group walked significantly faster with FES than without (25ftWT; p = 0.029, 5minSSWT; p = 0.037). There were no differences in the fast-walking FES group or in the oxygen cost for either device.

Conclusion

AFO reduced walking speed, particularly in fast walkers. FES increased walking speed in slow, but not fast walkers.

Bespoke versus off-the-shelf ankle-foot orthosis for people with stroke: randomized controlled trial

OBJECTIVE

The aim of the study was to compare the effect of two designs of ankle-foot orthosis on people with stroke.

DESIGN

The study design was an assessor-blind, multicentre randomized controlled trial.

SETTING

The setting was community stroke services.

PARTICIPANTS

A total of 139 community-dwelling stroke survivors with limited mobility were recruited.

INTERVENTIONS

The two most commonly used types of ankle-foot orthosis (bespoke and off-the-shelf) were chosen.

MAIN MEASURES

The main measures of the study were as follows: short- (6 weeks) and long-term (12 weeks) effects on stroke survivors' satisfaction; adverse events; mobility (Walking Handicap Scale); fear of falling (Falls Efficacy Scale-International (FES-I)) and walking impairments (gait speed and step length using the 5-m walk test).

RESULTS

Long-term satisfaction was non-significantly higher in the off-the-shelf group: 72% versus 64%; OR (95% CI) = 0.64 (0.31 to 1.3); P = 0.21. No statistically significant differences were found between the orthoses except that the off-the-shelf group had less fear of falling at short-term follow-up than the bespoke group: mean difference (95% CI) = -4.6 (-7.6 to -1.6) points on the FES-I; P = 0.003.

CONCLUSION

No differences between off-the-shelf and bespoke ankle-foot orthoses were found except that participants in the off-the-shelf orthosis group had less fear of falling at short-term follow-up.

A randomized controlled trial on providing ankle-foot orthoses in patients with (sub-)acute stroke: Short-term kinematic and spatiotemporal effects and effects of timing

Initial walking function is often limited after stroke, and regaining walking ability is an important goal in rehabilitation. Various compensatory movement strategies to ensure sufficient foot-clearance are reported. Ankle-foot orthoses (AFOs) are often prescribed to improve foot-clearance and may influence these strategies. However, research studying effects of actual AFO-provision early after stroke is limited. We conducted an explorative randomized controlled trial and aimed to study the short-term effects of AFO-provision on kinematic and spatiotemporal parameters in patients early after stroke. In addition, we studied whether timing of AFO-provision influenced these effects. Unilateral hemiparetic patients maximal six weeks post-stroke were randomly assigned to AFO-provision: early (at inclusion) or delayed (eight weeks later). Three-dimensional gait-analysis with and without AFO in randomized order was performed within two weeks after AFO-provision. Twenty subjects (8 early, 12 delayed) were analyzed. We found significant positive effects of AFO-provision for ankle dorsiflexion at initial contact, foot-off and during swing (-3.6° (7.3) vs 3.0° (3.9); 0.0° (7.4) vs 5.2° (3.7); and -6.1° (7.8) vs 2.6° (3.5), respectively), all p<0.001. No changes in knee, hip and pelvis angles were found after AFO-provision, except for knee (+2.3°) and hip flexion (+1.6°) at initial contact, p≤0.001. Significant effects of AFO-provision were found for cadence (+2.1 steps/min, p=0.026), stride duration (-0.08s, p=0.015) and single support duration (+1.0%, p=0.002). Early or delayed AFO-provision after stroke did not affect results. In conclusion, positive short-term effects of AFO-provision were found on ankle kinematics early after stroke. Timing of AFO-provision did not influence the results.

TRIAL REGISTRATION NUMBER

NTR1930.

Short-term effects of physiotherapy combining repetitive facilitation exercises and orthotic treatment in chronic post-stroke patients

[Purpose] This study investigated the short-term effects of a combination therapy consisting of repetitive facilitative exercises and orthotic treatment. [Subjects and Methods] The subjects were chronic post-stroke patients (n=27; 24 males and 3 females; 59.3 ± 12.4 years old; duration after onset: 35.7 ± 28.9 months) with limited mobility and motor function. Each subject received combination therapy consisting of repetitive facilitative exercises for the hemiplegic lower limb and gait training with an ankle-foot orthosis for 4 weeks. The Fugl-Meyer assessment of the lower extremity, the Stroke Impairment Assessment Set as a measure of motor performance, the Timed Up & Go test, and the 10-m walk test as a measure of functional ambulation were evaluated before and after the combination therapy intervention. [Results] The findings of the Fugl-Meyer assessment, Stroke Impairment Assessment Set, Timed Up & Go test, and 10-m walk test significantly improved after the intervention. Moreover, the results of the 10-m walk test at a fast speed reached the minimal detectible change threshold (0.13 m/s). [Conclusion] Short-term physiotherapy combining repetitive facilitative exercises and orthotic treatment may be more effective than the conventional neurofacilitation therapy, to improve the lower-limb motor performance and functional ambulation of chronic post-stroke patients.

Development and reliability of a measure evaluating dynamic proprioception during walking with a robotized ankle-foot orthosis, and its relation to dynamic postural control

BACKGROUND

Proprioception is important for proper motor control. As the central nervous system modulates how sensory information is processed during movement (sensory gating), proprioceptive tests performed at rest do not correlate well with performance during dynamic tasks such as walking. Proprioception therefore needs to be assessed during movement execution.

OBJECTIVES

1) To develop a test evaluating the ability to detect movement errors during walking, and its test-retest reliability; 2) to quantify the relationship between proprioceptive threshold (obtained with this new test) and performance in a standardized dynamic balance task.

METHOD

Thirty healthy subjects walked on a treadmill while wearing a robotized ankle-foot orthosis (rAFO) for 2 bouts of 6min on 2 evaluation sessions (test-retest reliability). Force perturbations resisting ankle dorsiflexion during swing were applied to the ankle via the rAFO (150ms duration, variable amplitude). Participants pushed a button when they detected the perturbations. The Star Excursion Balance Test (SEBT) was used to evaluate dynamic balance.

ANALYSIS

Angular differences between perturbed and non-perturbed gait cycles were used to quantify movement error. Detection threshold was defined as the minimal movement error at which 50% of the perturbations were perceived. Intraclass correlation coefficients (ICCs) estimated test-retest reliability, and Pearson coefficients were used to determine the correlation between detection threshold and SEBT.

RESULTS

Detection threshold was 5.31±2.12°. Good reliability (ICC=0.70) and a moderate to strong correlation to SEBT (r=-0.57 to -0.76) were found.

CONCLUSION

Force perturbations produced by the robotized AFO provides a reliable way of evaluating proprioception during walking.

Effect of ankle-foot orthosis on weight bearing of chronic stroke patients performing various functional standing tasks

[Purpose] This study examined how an ankle-foot orthosis (AFO) influences the weight-bearing of chronic stroke patients during the performance of five functional standing tasks. [Subjects and Methods] Sixteen patients with stroke participated in this experiment. The subjects performed functional standing tasks with or without the AFO and weight bearing was measured during the tasks. [Results] Patients showed increased weight-bearing ability on the affected side during wearing the AFO in all tasks, and there were significant differences among Tasks 1, 2, and 3. Patients showed a small amount of increased weight bearing on the unaffected side while wearing the AFO in all tasks except for Task 2. [Conclusion] ADL-related functional standing tasks with AFO increased the weight bearing.

Ankle-foot orthoses that restrict dorsiflexion improve walking in polio survivors with calf muscle weakness

In polio survivors with calf muscle weakness, dorsiflexion-restricting ankle-foot orthoses (DR-AFOs) aim to improve gait in order to reduce walking-related problems such as instability or increased energy cost. However, evidence on the efficacy of DR-AFOs in polio survivors is lacking. We investigated the effect of DR-AFOs on gait biomechanics, walking energy cost, speed, and perceived waking ability in this patient group. Sixteen polio survivors with calf muscle weakness underwent 3D-gait analyses to assess gait biomechanics when walking with a DR-AFOs and with shoes only. Ambulant registration of gas-exchange during a 6 min walk test determined walking energy cost, and comfortable gait speed was calculated from the walked distance during this test. Perceived walking ability was assessed using purposely-designed questionnaires. Compared with shoes-only, walking with the DR-AFOs significantly increased forward progression of the center of pressure (CoP) in mid-stance and it reduced ankle dorsiflexion and knee flexion in mid- and terminal stance (p < 0.05). Furthermore, walking energy cost was lower (-7%, p = 0.052) and gait speed was higher (p = 0.005). Patients were significantly more satisfied, felt safer, and less exhausted with the DR-AFO, compared to shoes-only (p < 0.05). DR-AFO effects varied largely across patients. Patients who walked with limited forward CoP progression and persisting knee extension during the shoes-only condition seemed to have benefitted least from the DR-AFO. In polio survivors with calf muscle weakness, DR-AFOs improved gait biomechanics, speed, and perceived walking ability, compared to shoes-only. Effects may depend on the shoes-only gait pattern, therefore further study is needed to determine which patients benefit most from the DR-AFO.

Effect of Ankle-foot Orthosis on Lower Limb Muscle Activities and Static Balance of Stroke Patients Authors' Names

[Purpose] This study examined the effects of an ankle-foot orthosis worn during balance training on lower limb muscle activity and static balance of chronic stroke patients. [Subjects] The subjects were twenty-five inpatients receiving physical therapy for chronic stroke. [Methods] The chronic stroke patients were divided into two groups: thirteen patients were assigned to the ankle-foot orthosis group, while the remaining twelve patients wore only their shoes. Each group performed balance training for 20 minutes, twice per day, 5 days per week, for 6 weeks. The lower limb muscle activities of the paralyzed side tibialis anterior, medial gastrocnemius, and the stability index were measured before and after the 6-week intervention. [Results] Comparison of the groups indicated a significant difference in the muscle activity of the paralyzed side tibialis anterior and the stability index of the eyes-open standing position. After the intervention, the ankle-foot orthosis group evidenced a significant difference in the muscle activities of the paralyzed side tibialis anterior and paralyzed side medial gastrocnemius as well as the stability index of the eyes-open standing position, eyes-closed standing position, eyes-open standing position on a sponge, and eyes-closed standing position on a sponge. The group that only wore their shoes showed significant differences in the stability indexes of eyes-open standing and eyes-open standing on a sponge. [Conclusion] Using the ankle-foot orthosis was effective during the initial training of lower limb muscle activities and the static balance training of chronic stroke patients. However, it was not effective for a variety of dynamic situations.

Effects on foot external rotation of the modified ankle-foot orthosis on post-stroke hemiparetic gait

Objective

To evaluate the effects of heel-opened ankle foot orthosis (HOAFO) on hemiparetic gait after stroke, especially on external foot rotation, and to compare the effects of HOAFO with conventional plastic-AFO (pAFO) and barefoot during gait.

Methods

This cross-over observational study involved 15 hemiparetic patients with external rotation of the affected foot. All subjects were able to walk independently, regardless of their usual use of a single cane, and had a less than fair-grade in ankle dorsiflexion power. Each patient was asked to walk in three conditions with randomized sequences: 1) barefoot, 2) with a pAFO, and 3) with an HOAFO. Their gait patterns were analyzed using a motion analysis system.

Results

Fifteen patients consisted of nine males and six females. On gait analysis, hip and foot external rotation were significantly greater in pAFO (-3.35° and -23.68°) than in barefoot and HOAFO conditions (p<0.05). Wearing an HOAFO resulted in significant decreases in hip (0.78°, p=0.04) and foot (-17.99°, p<0.01) external rotation compared with pAFO; although there was no significant difference between HOAFO and barefoot walking. Walking speed and percentage of single limb support were significantly greater for HOAFO than in barefoot walking.

Conclusion

HOAFO was superior to pAFO in reducing hip and foot external rotation during the stance phase in patients with post-stroke hemiparesis. HOAFO may, therefore, be useful in patients with excessive external rotation of the foot during conventional pAFO.

Effects of plantar flexion resistive moment generated by an ankle-foot orthosis with an oil damper on the gait of stroke patients: a pilot study

BACKGROUND

An ankle-foot orthosis with an oil damper was previously developed to assist the first rocker function during gait, but the effects of the amount of resistive moment generated on gait have not been clarified.

OBJECTIVES

To measure the amount of resistive moment generated by the ankle-foot orthosis with an oil damper during gait and determine its effect on the gait of patients with stroke.

STUDY DESIGN

Preliminary cross-sectional study.

METHODS

The gait of four patients with stroke in the chronic phase was measured in four conditions: without an ankle-foot orthosis and with the ankle-foot orthosis with an oil damper generating three different amounts of resistive moment. Measurements were taken with a three-dimensional motion analysis system and a specially designed device to determine the resistive moment.

RESULTS

The resistive moment was observed in the former half in stance of the paretic limb, and its magnitude was less than 10 N m. Some gait parameters related to terminal stance and preswing were affected by the amount of resistive moment. The forward component of floor reaction force and the shank vertical angle showed peak values when the patients reported feeling most comfortable during gait.

CONCLUSION

Although the resistive moment generated by the ankle-foot orthosis with an oil damper was small, it was sufficient to alter gait.

CLINICAL RELEVANCE

To maximize the effectiveness of ankle-foot orthoses, it is necessary to know the effects of resistive moment on the gait of patients with stroke. The ankle-foot orthosis with an oil damper assists the first rocker function in gait and also affects the gait in a later phase in stance. The peak values of some gait parameters coincided with patients reporting gait to be most comfortable. It is important to know that ankle-foot orthosis with an oil damper assistance in the first rocker alters the weight acceptance on the paretic limb and affects the gait parameters related to propulsion ability in stance.

Effect of ankle-foot orthosis on postural control after stroke: a systematic review

INTRODUCTION

Stroke is currently the main cause of permanent disability in adults. The impairments are a combination of sensory, motor, cognitive and emotional changes that result in restrictions on the ability to perform basic activities of daily living (BADL). Postural control is affected and causes problems with static and dynamic balance, thus increasing the risk of falls and secondary injuries. The purpose of this review was to compile the literature to date, and assess the impact of ankle-foot orthosis (AFO) on postural control and gait in individuals who have suffered a stroke.

DEVELOPMENT

The review included randomised and controlled trials that examined the effects of AFO in stroke patients between 18 and 80 years old, with acute or chronic evolution. No search limits on the date of the studies were included, and the search lasted until April 2011. The following databases were used: Pubmed, Trip Database, Cochrane library, Embase, ISI Web Knowledge, CINHAL and PEDro. Intervention succeeded in improving some gait parameters, such as speed and cadence. However it is not clear if there was improvement in the symmetry, postural sway or balance.

CONCLUSIONS

Because of the limitations of this systematic review, due to the clinical diversity of the studies and the methodological limitations, 0these results should be considered with caution.