Changes in muscle activity in children with hemiplegic cerebral palsy while walking with and without ankle-foot orthoses

A 10.5-year follow-up of walking with unilateral spastic cerebral palsy

Purpose

The purpose of this study was to describe gait evolution in patients with unilateral spastic cerebral palsy (USCP) using modified Gait Profile Score (mGPS without hip rotation), Gait Variable Score (GVS), walking speed, and the observed effects of single-level surgery (SLS) after 10 years.

Methods

Fifty-two patients with USCP (Gross Motor Function Classification System I) and data from two Clinical Gait Analyses (CGAs) were included. The evolution of patients' mGPS, GVS, and walking speed were calculated. Two "no surgery" and "single-level surgery" patient categories were analyzed. Paired t-tests were used to compare the data between CGAs and as a function of treatment category. Pearson's correlations were used to examine relationships between baseline values and evolutions in mGPS and walking speed.

Results

Mean ages (SD) at first and last CGAs were 9.3 (3.2) and 19.7 (6.0) years old, respectively, with an average follow-up of 10.5 (5.6) years. Mean mGPS for the patients' affected side was significantly lower at the last CGA for the full cohort: baseline = 8.5° (2.1) versus follow-up = 7.2° (1.6), effect size = 0.73, p < 0.001. Significant improvements in mGPS and GVS for ankle and foot progression were found for the SLS group. The mGPS change and mGPS at baseline (r = -0.79, p < 0.001) were negatively correlated.

Conclusions

SLS patients demonstrated a positive long-term change in gait pattern over time. The group that had undergone surgery had worse gait scores at baseline than the group that had not, but the SLS group's last CGA scores were relatively closer to those of the "no surgery" group.

Level of evidence

This was a retrospective comparative therapeutic study (level III).

Bilateral vs. Paretic-Limb-Only Ankle Exoskeleton Assistance for Improving Hemiparetic Gait: A Case Series

People with lower-limb hemiparesis have impaired function on one side of the body that affects their walking ability. Wearable robotic assistance has been investigated to treat hemiparetic gait by applying assistance to the paretic limb. In this exploratory case series, we sought to compare the effects of bilateral vs. paretic-limb-only ankle exoskeleton assistance on walking performance in a case series of three heterogeneous presentations of lower-limb hemiparesis. A secondary goal was to validate the use of a real-time ankle-moment-adaptive exoskeleton control system for effectively assisting hemiparetic gait; the ankle moment controller accuracy ranged from 72 - 90% across all conditions and participants. Compared to walking without the device, both paretic-limb-only and bilateral assistance resulted in greater average total ankle power (up to 72%), improved treadmill walking efficiency (up to 28%), and increased over-ground walking distance (up to 41%). All participants achieved a more symmetrical, efficient gait pattern with bilateral assistance, indicating that assisting both limbs may be more beneficial than assisting only the paretic side in people with hemiparetic gait. The results of this case series are intended to inform future clinical studies and exoskeleton designs in a wide range of patient populations.

Relationship between ankle function and walking ability for children and young adults with cerebral palsy: A systematic review of deficits and targeted interventions

BACKGROUND

A primary goal of treatment for children with cerebral palsy is improved walking ability to allow for a more active and independent lifestyle. With the importance of ankle function to walking ability, and the deficits in ankle function associated with cerebral palsy, there is good rationale for targeting this joint in an effort to improve walking ability for this population.

RESEARCH QUESTION

How do deficits and targeted interventions of the ankle joint influence walking ability in children with cerebral palsy?

METHODS

A specific search criteria was used to identify articles that either (1) provided information on the relationship between ankle function and walking ability or (2) investigated the effect of a targeted ankle intervention on walking ability in cerebral palsy. PubMed, Embase, CINAHL, and Web of Science databases were searched from 1980-April, 2020. Resulting citations were compared against a prospective set of inclusion and exclusion criteria. Data relevant to the original research question was extracted, and the level of evidence for each intervention study was scored. Interpretation was focused on specific, pre-determined mobility measures.

RESULTS

Sixty-one citations met all criteria for data extraction, six of which were observational, and fifty-five of which were interventional. Level of evidence ranged from 2 to 4. Self-selected walking speed was the most common measure of walking ability, while physical activity level was the least common.

SIGNIFICANCE

Ankle function is an important contributor to the walking ability of children with cerebral palsy, and most interventions targeting the ankle seem to demonstrate a benefit on walking ability, but future higher-powered and/or controlled studies are necessary to confirm these findings.

Clinical Relevance of State-of-the-Art Analysis of Surface Electromyography in Cerebral Palsy

Surface electromyography (sEMG) can be used to assess the integrity of the neuromuscular system and its impairment in neurological disorders. Here we will consider several issues related to the current clinical applications, difficulties and limited usage of sEMG for the assessment and rehabilitation of children with cerebral palsy. The uniqueness of this methodology is that it can determine hyperactivity or inactivity of selected muscles, which cannot be assessed by other methods. In addition, it can assist for intervention or muscle/tendon surgery acts, and it can evaluate integrated functioning of the nervous system based on multi-muscle sEMG recordings and assess motor pool activation. The latter aspect is especially important for understanding impairments of the mechanisms of neural controllers rather than malfunction of individual muscles. Although sEMG study is an important tool in both clinical research and neurorehabilitation, the results of a survey on the clinical relevance of sEMG in a typical department of pediatric rehabilitation highlighted its limited clinical usage. We believe that this is due to limited knowledge of the sEMG and its neuromuscular underpinnings by many physiotherapists, as a result of lack of emphasis on this important methodology in the courses taught in physical therapy schools. The lack of reference databases or benchmarking software for sEMG analysis may also contribute to the limited clinical usage. Despite the existence of educational and technical barriers to a widespread use of, sEMG does provide important tools for planning and assessment of rehabilitation treatments for children with cerebral palsy.

Amplitude and stride-to-stride variability of muscle activity during Lokomat guided walking and treadmill walking in children with cerebral palsy

BACKGROUND

The Lokomat is a commercially available exoskeleton for gait training in persons with cerebral palsy (CP). Because active contributions and variability over movement repetitions are determinants of training effectiveness, we studied muscle activity in children with CP, and determined (i) differences between treadmill and Lokomat walking, and (ii) the effects of Lokomat training parameters, on the amplitude and the stride-to-stride variability.

METHODS

Ten children with CP (age 13.2 ± 2.9, GMFCS level II(n = 6)/III(n = 4)) walked on a treadmill (±1 km/h; 0% bodyweight support(BWS)), and in the Lokomat (50% and 100% guidance; ±1 km/h and ±2 km/h; 0% and 50% BWS). Activity was recorded from Gluteus Medius (GM), Vastus Lateralis (VL), Biceps Femoris (BF), Medial Gastrocnemius (MG) and Tibialis Anterior (TA) of the most affected side. The averaged amplitude per gait phase, and the second order coefficient of variation was used to determine the active contribution and stride-to-stride variability, respectively.

RESULTS

Generally, the amplitude of activity was lower in the Lokomat than on the treadmill. During Lokomat walking, providing guidance and BWS resulted in slightly lower amplitudes whereas increased speed was associated with higher amplitudes. No significant differences in stride-to-stride variability were observed between Lokomat and treadmill walking, and in the Lokomat only speed (MG) and guidance (BF) affected variability.

CONCLUSIONS

Lokomat walking reduces muscle activity in children with CP, whereas altering guidance or BWS generally does not affect amplitude. This urges additional measures to encourage active patient contributions, e.g. by increasing speed or through instruction.

Bilateral symmetry in leg and joint stiffness in children with spastic hemiplegic cerebral palsy during gait

Deviations are often identified at individual joints in the gait analysis of patients with cerebral palsy. Previous gait studies on hemiplegic cerebral palsy (HCP) have focused mainly on deviations of the affected side. The current study aimed to quantify and compare the joint and leg stiffness, the contributions of skeletal and muscular components, and the associated joint angles and moments of the affected and nonaffected lower limbs during level walking in children with spastic HCP. A total of 12 children with spastic HCP and 12 healthy controls walked at a self-selected speed in a gait laboratory while their kinematic and forceplate data were measured and analyzed during loading response, midstance, terminal stance, and preswing. The altered joint kinematics and kinetics in the nonaffected limb in the HCP group appeared to be mainly a compensatory strategy to minimize the bilateral asymmetry in leg stiffness during the double-limb support phase and joint stiffness during the entire stance phase. The current results suggest that therapeutic planning and decision-making for children with HCP should consider not only the mechanics of the affected side but also the control of the nonaffected side.

Muscle activity in children with spastic unilateral cerebral palsy when walking with ankle-foot orthoses: an explorative study

BACKGROUND

A hinged ankle-foot orthosis is prescribed for children with spastic unilateral cerebral palsy to improve gait function by correcting spastic equinus. However, little is known about how orthotic management relates to muscle activity during walking in this population.

RESEARCH QUESTION

Does muscle activity in medial gastrocnemius and tibialis anterior change in children with spastic unilateral cerebral palsy when walking with hinged ankle-foot orthoses featuring two different footplate designs?

METHODS

In this prospective, repeated-measures trial, electromyographic activity in medial gastrocnemius and tibialis anterior was recorded from 17 children (mean age: 8.4 years ± 1.3 years) with spastic unilateral cerebral palsy walking barefoot and with two designs of hinged ankle-foot orthosis. The orthotic devices consisted of custom-made hinged ankle-foot orthoses with unmodified, flatter footplates and rectified, contoured footplates. Primary outcome measures were total muscle activity, quantified as the area under a linear envelope, and relative change in profiles of muscle activity, depicted by curves of mean difference with 95% confidence bands.

RESULTS

No statistical difference was found in total activity of either muscle for the ankle-foot orthosis with an unmodified footplate but a significant reduction in muscle activity of tibialis anterior was seen for the ankle-foot orthosis with a contoured footplate relative to barefoot walking. Profiles of change in muscle activity were significantly altered for both shank muscles between all walking conditions. The most pronounced differences were decreased activity in medial gastrocnemius during early stance phase and lower activity in tibialis anterior during swing phase with orthotic devices.

SIGNIFICANCE

Orthotic management with hinged ankle-foot orthoses may mitigate spastic activation of medial gastrocnemius in children with spastic unilateral cerebral palsy but also appears to functionally inactivate tibialis anterior during gait. The hinged ankle-foot orthosis with an unmodified footplate corresponded with better performance by facilitating more functional muscle activity while impeding spastic response.

Reliability and minimum detectable change of measures of gait in children during walking and running on an instrumented treadmill

BACKGROUND

Instrumented treadmills that incorporate pressure platforms are increasingly used to characterize gait in children. Although footprint size is known to influence the measurement performance of pressure platforms, published evidence on the reliability of such systems for children's gait is lacking.

RESEARCH QUESTION

This study evaluated the test-retest reliability of temporospatial gait parameters and vertical ground reaction forces measured in healthy children during barefoot walking and running on a capacitance-based treadmill system.

METHODS

Temporospatial gait parameters, including cadence, stride length, stride duration, stance and swing phase durations and the magnitude and timing of conventional vertical ground reaction force peaks were determined on two occasions in 17 healthy children (mean age, 11 ± 2 years; height, 148.4 ± 9.3 cm; and mass, 43.3 ± 10 kg) during walking and running at preferred speed on an instrumented treadmill. Reliability was assessed using Intra Class Correlation Coefficients (ICC) and the standard error of measurement (SEM). The minimum detectable change (MDC95%) was also calculated.

RESULTS

ICC values ranged from 0.91-0.99 for all variables. When expressed as a percentage of the mean, the SEM was <5% for all gait parameters assessed during walking and running. The MDC95% values for gait parameters were typically higher during running than walking, and were ±4% of the gait cycle for temporal parameters, ±55 cm for stride length and ±0.1 bodyweights for peak vertical ground reaction force.

SIGNIFICANCE

Children's gait parameters varied by <5% between test occasions and were more consistent during walking than running. These findings provide clinicians and researchers with an index of the reliability and sensitivity of the treadmill to detect changes in common spatiotemporal gait parameters and vertical ground reaction forces in children.

Comparison of Gait Ability of a Child with Cerebral Palsy According to the Difference of Dorsiflexion Angle of Hinged Ankle-Foot Orthosis: A Case Report

Patient: Female, 8

Final Diagnosis: Cerebral palsy

Symptoms: Gait abnormality

Medication: —

Clinical Procedure: —

Specialty: Rehabilitation

Architectural Changes in the Medial Gastrocnemius on Sonography after Nerve Ablation in Healthy Adults

Architectural changes in healthy muscle after denervation have not yet been reported. This study aimed to investigate architectural changes in the medial head of the gastrocnemius muscle (GCM) after aesthetic tibial nerve ablation in healthy adults using ultrasonography (US). The effects of tibial nerve ablation were verified by visual observation and surface electromyography analysis. US images of medial GCMs were taken by one trained physician using B-mode and real-time US with a linear-array probe before nerve ablation, at 1 week after nerve ablation and at 3 months after nerve ablation in an anatomic standing position with the feet about shoulder-width apart in 19 healthy adults (17 females and 2 males). Muscle thickness was significantly reduced on the left side at 1 week and 3 months after the procedure and on the right side at 3 months after the procedure (p<0.050). Although fascicle length was not significantly changed, pennation angle was significantly reduced on both sides at 3 months after the procedure (p<0.050). Muscle thickness and pennation angle of the muscle fascicle were significantly reduced, although fascicle length was not significantly changed, after tibial nerve ablation in the medial GCM of healthy adults.

Paralysis of the gastrocnemius medial head differentially affects gait patterns and muscle activity during level and stair ascent locomotion

BACKGROUND

Prior studies have analyzed the activity of the gastrocnemius (GCM) medial and lateral heads as a single unit because it is technically challenging to separately analyze the function of each component in vivo. However, functional variation between the medial and lateral heads is expected due to their anatomical differences.

RESEARCH QUESTION

What is the independent function of the medial GCM? How does paralysis of the GCM medial head affect gait kinematics?.

METHODS

Twelve healthy adults (two males and ten females; age: 28.2 [±7.72] years) that were scheduled to undergo neurolysis of the tibial nerve branch supplying the medial head of the GCM for aesthetic calf reduction participated in the study. Gait analysis was performed using a computerized opto-electric gait analysis system to measure kinematic data. Surface electromyography (EMG) was recorded simultaneously during the gait analysis. Surface electrodes were placed on seven muscles. Pre-procedure and 1-week and 3-month post-procedure data were compared using a linear mixed model.

RESULTS

During level walking, decreased activity of the GCM medial head did not significantly change gait kinematics. However, a significant increase in GCM lateral head and hamstring activities occurred after a branch nerve block to the GCM medial head. During stair ascent, in contrast to level walking, changes in EMG activity only occurred in the GCM medial head, and post-procedure ankle dorsiflexion angles at the end of the terminal-stance phase significantly increased. Ankle plantarflexion angles during the push-off phase were also decreased when compared with pre-procedure values.

SIGNIFICANCE

The human body response to dysfunction of the GCM medial head depended on the type of locomotion.

Muscle fatigue during a short walking exercise in children with cerebral palsy who walk in a crouch gait

BACKGROUND

A deterioration of crouch gait was found in a group of children with cerebral palsy (CP) after a short walking exercise. The increased knee flexion reported after a continuous walk could be related with muscle fatigue and muscle strength.

AIM

Does muscle fatigue appears at the end of a walking exercise in children with CP who walk in a crouch gait?

METHODS

Eleven children with cerebral palsy (GMFCS I to III) who walk in a crouch gait were included. Isometric muscle strength was assessed using a handheld dynamometer. Children were asked to walk for 6 min at comfortable speed. Spatio-temporal, kinematic and electromyographic (EMG) measurements were recorded at the first and the last minute of the 6-minute walking exercise. Muscle fatigue was evaluated using the shift of EMG signals median frequency.

RESULTS

There was no significant difference in walking speed, cadence, and step length at the end of the 6mwe. Maximal and mean anterior pelvic tilt decreased and knee flexion increased (p < 0.05). Rectus femoris EMG median frequency decreased (p < 0.05). The median frequency in other muscles did not decrease significantly. Greater hip extensor strength was associated with lesser knee flexion at the end of the 6-minute walking exercise (p < 0.05).

SIGNIFICANCE

The increase in knee flexion at the end of the 6-minute walking exercise can be explained by muscle fatigue found in rectus femoris. Hip extensor strength can limit the deterioration of crouch gait after a 6-minute walking exercise representative of daily activities.

Efficacy of different techniques of AFO construction for hemiplegia patients: A systematic review

Background: Ankle foot orthoses (AFOs) are frequently prescribed to improve gait deviation and normalize walking pattern in patients with drop foot hemiplegia disorder. This study was to review the efficacy of different techniques of AFO construction and biomechanics parameters of AFOs. Furthermore, this study aimed to provide a guideline for researchers in detail and help them choose a sufficient measurement instrument.

Methods: Information sources included MEDLINE, CINAHL, Scopus, PubMed, and the Full Cochrane Library up to December 25, 2015. The inclusion criteria include: (1) type and method of controlled clinical trial studies; (2) age of hemiplegia groups (3); AFOs as an intervention; and (4) kinetic and kinematic parameters, and energy expenditure as an intervention of gait performance.

Results: Considering eligibility criteria such as study design, setting, time frame and Language 9 papers with Pedro scores of 5 to 8 for methodological quality were included in the review.

Conclusion: The findings of this review can help to develop guidelines for the best AFO reporting as an intervention and to prevent vagueness of results in the different types of AFOs.

Correction of Planovalgus Deformity Through Rotational Reinsertion of the Lateral Layers of the Achilles Tendons in Ambulatory Children With Cerebral Palsy

Symptomatic planovalgus deformity is a condition commonly seen in patients with cerebral palsy. The authors propose a new procedure for the management of this deformity through rotational reinsertion of the lateral layers of the Achilles tendon, and then they assess its benefit by comparing plantar pressure distribution patterns in children preoperatively and at 6- and 12-month intervals postoperatively. Pedobarographic measurements, range of motion of the ankle, and radiographic indexes were used to assess the outcome of the surgery. The functional abilities of the patients were assessed based on the Gross Motor Function Classification System. A total of 37 feet (22 patients) were included, with a mean ± standard deviation age at surgery of 11.8 ± 2.7 (range 9.1 to 14.5) years. All feet were managed through rotational reinsertion of the lateral layers of the Achilles tendon. Surgical correction of planovalgus has good outcomes. Significant changes were observed with statistical significance at the 5% (p ≤ .05) level in plantar pressure distribution in children preoperatively and at 6- and 12-month intervals postoperatively. The results show that the proposed method of surgery is effective in the correction of planovalgus in ambulatory children with cerebral palsy.

Comparison of gait with and without ankle-foot orthoses after lower limb surgery in children with unilateral cerebral palsy

PURPOSE

Children with spastic unilateral cerebral palsy (SUCP) frequently undergo lower limb surgery to improve gait. Postoperatively, ankle-foot orthoses (AFOs) are used to maintain the surgical corrections and provide adequate mechanical support. Our aim was to evaluate changes in gait and impacts of AFOs one-year postoperatively.

METHODS

In all, 33 children with SUCP, 17 girls and 16 boys, mean age 9.2 years (5 to 16.5) were measured by 3D gait analysis walking barefoot preoperatively and walking barefoot and with AFOs one-year postoperatively. Changes in Gait Profile Scores (GPS), kinematic, kinetic and temporal spatial variables were examined using linear mixed models, with gender, gross motor function and AFO type as fixed effects.

RESULTS

The results confirm significant gait improvements in the GPS, kinematics and kinetics walking barefoot one year after surgery. Comparing AFOs with barefoot walking postoperatively, there was additionally reduced ankle plantarflexion by an average of 5.1° and knee flexion by 4.7° at initial contact, enhanced ankle moments during loading response, increased velocity, longer steps and inhibited push-off power generation. Stance and swing phase dorsiflexion increased in children walking with hinged AFOs versus children walking with ground reaction AFOs. Changes in the non-affected limbs indicated less compensatory gait postoperatively.

CONCLUSION

Major changes were found between pre- and postoperative barefoot conditions. The main impact of AFOs was correction of residual drop foot and improved prepositioning for initial contact, which could be considered as indications for continued use after the one-year follow-up.

LEVEL OF EVIDENCE

Level II - Therapeutic.

Physical therapist's clinical reasoning in patients with gait impairments from hemiplegia

Background: During stroke rehabilitation, physical therapists (PTs) perform gait analysis and design treatments based on this analysis. Objectives: To investigate the current trends in PTs clinical reasoning in assessing and managing gait in persons with hemiplegia. Design: A qualitative study using a phenomenological approach using a semi-structured interview protocol with FG. Methods: Participants consisted of expert and novice PTs working in a neurologic rehabilitation setting. FG were conducted in person and via web. Constant comparative qualitative analysis was used to analyze the qualitative data. Results: A total of 22 PTs participated in five FG (2 novice and 3 expert groups). From the analysis of qualitative data, five themes emerged. Novice and experienced clinicians: 1) take a systematic approach to examination and evaluation of persons with hemiplegia; 2) are in agreement in common gait deficits found in persons with hemiplegia; 3) may differ in their approach to treatment based on the amount of experience of the clinician; 4) generally agree on the manner in which orthotics are used in the management of persons with hemiplegia; and 5) demonstrate professional accountability to patients concerning the use of orthotic devices. Conclusions: This qualitative study provided insight into the variability in PTs' strategies for gait analysis, and their identification and interpretation of common deviations and impairments in persons with hemiplegia following stroke. Reluctance to utilize orthotics for patients with hemiplegia was a consistent theme across FG.

Effect of ankle-foot orthoses on gait, balance and gross motor function in children with cerebral palsy: a systematic review and meta-analysis

Objective:

To determine the effects of ankle-foot orthoses (AFOs) on gait, balance, gross motor function and activities of daily living in children with cerebral palsy.

Data sources:

Five databases were searched (Pubmed, Psycinfo, Web of Science, Academic Search Premier and Cochrane Library) before January 2018.

Review methods:

Studies of the effect of AFOs on gait, balance, gross motor function and activities of daily living in children with cerebral palsy were included. Articles with a modified PEDRO score ≥ 5/9 were selected. Data regarding population, AFO, interventions and outcomes were extracted. When possible, standardized mean differences (SMDs) were calculated from the outcomes.

Results:

Thirty-two articles, corresponding to 56 studies (884 children) were included. Fifty-one studies included children with spastic cerebral palsy. AFOs increased stride length (SMD = 0.88, P < 0.001) and gait speed (SMD = 0.28, P < 0.001), and decreased cadence (SMD = –0.72, P < 0.001). Gross motor function scores improved (Gross Motor Function Measure (GMFM) D (SMD = 0.30, P = 0.004), E (SMD = 0.28, P = 0.02), Pediatric Evaluation of Disability Inventory (PEDI) (SMD = 0.57, P < 0.001)). Data relating to balance and activities of daily living were insufficient to conclude. Posterior AFOs (solid, hinged, supra-malleolar, dynamic) increased ankle dorsiflexion at initial contact (SMD = 1.65, P < 0.001) and during swing (SMD = 1.34, P < 0.001), and decreased ankle power generation in stance (SMD = –0.72, P < 0.001) in children with equinus gait.

Conclusion:

In children with spastic cerebral palsy, there is strong evidence that AFOs induce small improvements in gait speed and moderate evidence that AFOs have a small to moderate effect on gross motor function. In children with equinus gait, there is strong evidence that posterior AFOs induce large changes in distal kinematics.

Testing Gait with Ankle-Foot Orthoses in Children with Cerebral Palsy by Using Functional Mixed-Effects Analysis of Variance

Existing statistical methods extract insufficient information from 3-dimensional gait data, rendering clinical interpretation of impaired movement patterns sub-optimal. We propose an alternative approach based on functional data analysis that may be worthy of exploration. We apply this to gait data analysis using repeated-measurements data from children with cerebral palsy who had been prescribed fixed ankle-foot orthoses as an example. We analyze entire gait curves by means of a new functional F test with comparison to multiple pointwise F tests and also to the traditional method - univariate repeated-measurements analysis of variance of joint angle minima and maxima. The new test maintains the nominal significance level and can be adapted to test hypotheses for specific phases of the gait cycle. The main findings indicate that ankle-foot orthoses exert significant effects on coronal and sagittal plane ankle rotation; and both sagittal and horizontal plane foot rotation. The functional F test provided further information for the stance and swing phases. Differences between the results of the different statistical approaches are discussed, concluding that the novel method has potential utility and is worthy of validation through larger scale patient and clinician engagement to determine whether it is preferable to the traditional approach.

Do research papers provide enough information on design and material used in ankle foot orthoses for children with cerebral palsy? A systematic review

OBJECTIVES

The purpose of this article is to determine how many of the current peer-reviewed studies of ankle foot or-thoses (AFOs) on children with cerebral palsy (CP) have included adequate details of the design and material of the AFO, to enable the study to be reproduced and outcomes clearly understood.

METHODS

A thorough search of studies published in English was conducted in March 2015, with no restriction on dates, within all major databases using relevant phrases. These searches were then supplemented by tracking all key references from the appropriate articles identified.

STUDY SELECTION

The inclusion criteria were as follows: (1) population - children with CP; (2) intervention - AFOs; and (3) outcome measure. One reviewer extracted data regarding the characteristics of the included studies, with the extracted data checked for accuracy and completeness by a second reviewer. None of the studies reviewed gave adequate details of the AFOs. Only 3.6% (n = 2) of papers tested the stiffness. Many studies (54.5%) did not describe the material used nor the material thickness (72.7 %). None of them gave any clinical justification for the chosen design of AFO.

CONCLUSIONS

There is a clear paucity of detail regarding the design and material used in AFOs on studies involving children with CP. Such a lack of detail has the potential to affect the validity of the reported outcomes, the ability to reproduce the studies and may misinform clinical practice.

Orthotic correction of lower limb function during gait does not immediately influence spinal kinematics in spastic hemiplegic cerebral palsy

BACKGROUND AND PURPOSE

Foot equinus and leg length discrepancy (LLD) are common problems in hemiplegic cerebral palsy (hCP), both causing secondary deviations of pelvic motion during gait. It can therefore be assumed that the spinal deviations observed in hCP patients are secondary as a compensation for the position of the pelvis arising from the disturbed leg function. This study investigated the effects of correcting lower extremity function by orthotics on spinal gait kinematics in hCP patients.

METHODS

Ten adolescent hCP patients and 15 healthy controls were included. Using a validated and previously used enhanced marker set, sagittal and frontal plane spinal curvature angles as well as general trunk and lower extremity kinematics were measured while walking barefoot as well as with an orthotic correction (only hCP patients) using a 12-camera motion capture system.

RESULTS

The hCP patients in both the barefoot and orthotic conditions indicated clinically relevant greater lumbar lordosis angles (d≥0.96, p≤0.071), smaller thoracic kyphosis angles (d≥0.84, p≤0.142) and differences in frontal plane lumbar curvature angles (d≥1.00, p≤0.105) compared to controls. However, these angles were not influenced by the successful restoration of a normal heel-to-toe gait pattern and the correction of any LLD using lower extremity orthotics.

CONCLUSIONS

Spinal gait deviations in adolescents with mild hCP seemed not to result secondarily from foot equinus or LLD, but probably from structural deformities such as hip flexor contractures. Future research should address long-term effects of an AFO treatment as well as the relationship between spinal kinematics and severity of disease.

Multiple gait patterns within the same Winters class in children with hemiplegic cerebral palsy

BACKGROUND

Previous literature hypothesized that Winters type I are mainly characterized by a hypo-activation of dorsiflexors and type II by hyperactivation of plantarflexors around initial contact. However, it is currently not known if hemiplegic children belonging to the same Winters class really share the same muscle activation patterns, although this information might have relevant clinical implications in the patient management.

METHODS

Gait data of 38 hemiplegic cerebral palsy children (16 Winters type I, 22 Winters type II) were analyzed, focusing on the foot and shank. A 2.5-minute walk test was considered, corresponding to more than 100 gait cycles for each child, analyzing the muscle activation patterns of tibialis anterior and gastrocnemius lateralis. The large stride-to-stride variability of gait data was handled in an innovative way, processing separately: 1) distinct foot-floor contact patterns, and for each specific foot-floor contact pattern 2) distinct muscle "activation modalities", averaging only across gait cycles with the same number of activations, and obtaining, in both cases, the pattern frequency-of-occurrence.

FINDINGS

At least 2 representative foot-floor contact patterns within each Winters group, and up to 4-5 distinct muscle activation patterns were documented.

INTERPRETATION

It cannot be defined a predominant muscle activation pattern specific for a Winters group. For a correct clinical assessment of a hemiplegic child, it is advisable to record and properly analyze gait signals during a longer period of time (2-3 min), rather than (subjectively) selecting a few "clean" gait cycles, since these cycles may not be representative of the patient's gait.

Acclimatization of the gait pattern to wearing an ankle-foot orthosis in children with spastic cerebral palsy

BACKGROUND

Ankle-foot orthoses can be prescribed to improve gait in children with cerebral palsy. Before evaluating the effects of ankle-foot orthoses on gait, a period to adapt or acclimatize is usually applied. It is however unknown whether an acclimatization period is actually needed to reliably evaluate the effect of a new orthosis on gait. This study aimed to investigate whether specific gait parameters in children with cerebral palsy would change within an acclimatization period after being provided with new ankle-foot orthoses.

METHODS

Ten children with cerebral palsy, walking with excessive knee flexion in midstance (8 boys; mean (SD) 10.2 (1.9) years; Gross Motor Function Classification System levels I-II) were provided with ventral shell ankle-foot orthoses. The orthoses were worn in combination with the child's own shoes and tuned, based on ground reaction force alignment with respect to the lower limb joints. Directly after tuning (T0) and four weeks later (T1), 3D-gait analysis was performed using an optoelectronic motion capture system and a force plate. From this assessment, ten spatiotemporal, kinematic and kinetic gait parameters were derived for the most affected leg. Differences in parameters between T0 and T1 were analyzed using paired t-tests or Wilcoxon signed rank tests (P<0.05).

FINDINGS

Over the course of four weeks, no significant differences (P ≥ 0.080) were observed for any investigated parameter.

INTERPRETATION

These results imply that the biomechanical effect of ventral shell ankle-foot orthoses on gait in independent walking children with cerebral palsy is immediately apparent, i.e., there is no further change after acclimatization.

Gait mechanics in patients with chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by the frequent association of disease outside the lung. The objective of this study was to determine the presence of biomechanical gait abnormalities in COPD patients compared to healthy controls while well rested and without rest.

METHODS

Patients with COPD (N = 17) and aged-matched, healthy controls (N = 21) walked at their self-selected pace down a 10-meter walkway while biomechanical gait variables were collected. A one-minute rest was given between each of the five collected trials to prevent tiredness (REST condition). Patients with COPD then walked at a self-selected pace on a treadmill until the onset of self-reported breathlessness or leg tiredness. Subjects immediately underwent gait analysis with no rest between each of the five collected trials (NO REST condition). Statistical models with and without covariates age, gender, and smoking history were used.

RESULTS

After adjusting for covariates, COPD patients demonstrated more ankle power absorption in mid-stance (P = 0.006) than controls during both conditions. Both groups during NO REST demonstrated increased gait speed (P = 0.04), stride length (P = 0.03), and peak hip flexion (P = 0.04) with decreased plantarflexion moment (P = 0.04) and increased knee power absorption (P = 0.04) as compared to REST. A significant interaction revealed that peak ankle dorsiflexion moment was maintained from REST to NO REST for COPD but increased for controls (P < 0.01). Stratifying by disease severity did not alter these findings, except that step width decreased in NO REST as compared to REST (P = 0.01). Standardized effect sizes of significant effects varied from 0.5 to 0.98.

CONCLUSIONS

Patients with COPD appear to demonstrate biomechanical gait changes at the ankle as compared to healthy controls. This was seen not only in increased peak ankle power absorption during no rest but was also demonstrated by a lack of increase in peak ankle dorsiflexion moment from the REST to the NO REST condition as compared to the healthy controls. Furthermore, a wider step width has been associated with fall risk and this could account for the increased incidence of falls in patients with COPD.

Changes in muscle activity in typically developing children walking with unilaterally induced equinus

BACKGROUND

Distinguishing changes in lower limb muscle activation during gait caused by abnormal motor control or adaptations to the presence of a fixed equinus remains a challenge. The objective of this study was to determine a threshold degree of equinus at which changes in muscle activity occur and to characterize adaptive patterns of muscle activity in typically developing children walking with unilateral induced equinus.

METHODS

Ten typically developing children were included. A customized orthosis was fitted to the right ankle. Five conditions of dorsiflexion limitation were evaluated: 10° dorsiflexion, 0°, 10°, 20° of plantar flexion and maximum plantar flexion. Muscle activity of the rectus femoris, vastus lateralis, hamstring, tibialis anterior and soleus muscles of both limbs was recorded.

FINDINGS

Significant changes in muscle activation and co-activation occurred from 10° of plantar flexion in the orthosis limb and from maximum plantar flexion in the contralateral limb. Soleus activation occurred prematurely in terminal swing and increased with the degree of equinus. Tibialis anterior activation was increased during initial and midswing and was decreased during terminal swing. From the -20° condition, hamstring activation was increased during the loading response. Vastus lateralis and rectus femoris activation was increased during stance phase. Similar changes in tibialis anterior and soleus activation occurred on the contralateral side. Changes in co-activation occurred in the soleus/tibialis anterior muscle pair in both limbs.

INTERPRETATION

This study provides indications regarding changes in muscle activity during simulation of equinus gait which should be helpful for therapeutic decision making.

[Principles of treatment of spastic palsy in children: a critical review]

BACKGROUND

In patients with cerebral palsy who are able to walk the source of the problem of spasticity must first be correctly determined. The weakness appears to be the main problem and the first line treatment must concentrate on improvement of strength and bodily control.

THERAPY

Spasticity can also compensate for weaknesses. The indications for weakening measures for correction of muscle tonus must therefore be carefully appraised but are part of the repertoire. Orthoses result in stability and correction of deformities. Night braces are in our experience of doubtful value. Biomechanical objectives are a right-angle between the sole of the shoe and lower leg axis (leading edge of the tibia) and full passive and active extension in the knees and hips.

CONCLUSION

Severely handicapped patients often suffer from hip luxation and scoliosis. Regular control of the hips and spine under loading are necessary. Early interventions, conservative and operative, have a better prognosis than a late correction. In general patients who have a risk for deformities and dysfunction of the musculoskeletal system due to the underlying disease should undergo early orthopedic control.

Gait: the role of the ankle and foot in walking

Evaluation of gait and its associated deviations from normal requires an in-depth evaluation of the patient and an appreciation for the complexity of the task. Understanding gait starts with an appreciation of the basic determinants of gait. Foot drop is a common gait deviation. Functionally, a foot drop results in a long limb. This will result in alterations of the gait cycle during swing phase. The common compensations for a foot drop include steppage gait, circumduction, and a persistently abducted limb. Noninterventional options for management of common gait deviations secondary to ankle/foot dysfunction present challenges.

The effect of tuning ankle foot orthoses-footwear combination on the gait parameters of children with cerebral palsy

BACKGROUND

There are a wide variety of ankle foot orthoses used in clinical practice which are characterised by their design, the material used and the stiffness of that material. Changing any of these three components will alter the effect of the ankle foot orthosis on gait.

OBJECTIVES

The purpose of this article is to provide an overview on the available research on ankle foot orthosis-footwear combination tuning on the gait characteristics of children with cerebral palsy through a structured review.

STUDY DESIGN

Literature review.

METHODS

A thorough search of previous studies published in English was conducted within all major databases using relevant phrases without any limits for the dates. These searches were then supplemented by tracking all key references from the appropriate articles identified including hand searching of published books where relevant.

RESULTS

To date, there are 947 papers in the literature pertaining to the study of ankle foot orthosis. Of these, 153 investigated the use of ankle foot orthosis for children with cerebral palsy. All the studies included in this review were of a within-subjects design and the evidence levels were generally low.

CONCLUSIONS

The overall results suggested that ankle foot orthosis-footwear combination tuning has the potential to improve the kinematics and kinetics of gait in children with cerebral palsy. However, the review highlights a lack of well-designed and adequately powered studies. Clinical relevance While the research described in this article indicates an improvement in the gait of children with cerebral palsy following tuning of their ankle foot orthosis-footwear combination, there is still a paucity of research with quantitative data on the effects of kinematics and kinetics of ankle foot orthosis-footwear combination tuning, comparing untuned ankle foot orthosis-footwear combinations with tuned ankle foot orthosis-footwear combination. Furthermore, current research does not identify the effect of tuning on energy efficiency.

Randomized controlled trial of surface peroneal nerve stimulation for motor relearning in lower limb hemiparesis

OBJECTIVE

To compare the motor relearning effect of a surface peroneal nerve stimulator (PNS) versus usual care on lower limb motor impairment, activity limitation, and quality of life among chronic stroke survivors.

DESIGN

Single-blinded randomized controlled trial.

SETTING

Teaching hospital of academic medical center.

PARTICIPANTS

Chronic stroke survivors (N=110; >12wk poststroke) with unilateral hemiparesis and dorsiflexion strength of ≤4/5 on the Medical Research Council scale.

INTERVENTIONS

Subjects were stratified by motor impairment level and then randomly assigned to ambulation training with either a surface PNS device or usual care (ankle-foot orthosis or no device) intervention. Subjects were treated for 12 weeks and followed up for 6 months posttreatment.

MAIN OUTCOME MEASURES

Lower limb portion of the Fugl-Meyer (FM) Assessment (motor impairment), the modified Emory Functional Ambulation Profile (mEFAP) performed without a device (functional ambulation), and the Stroke Specific Quality of Life (SSQOL) scale.

RESULTS

There was no significant treatment group main effect or treatment group by time interaction effect on FM, mEFAP, or SSQOL raw scores (P>.05). The time effect was significant for the 3 raw scores (P<.05). However, when comparing average change scores from baseline (t1) to end of treatment (t2, 12wk), and at 12 weeks (t3) and 24 weeks (t4) after end of treatment, significant differences were noted only for the mEFAP and SSQOL scores. The change in the average scores for both mEFAP and SSQOL occurred between t1 and t2, followed by relative stability thereafter.

CONCLUSIONS

There was no evidence of a motor relearning effect on lower limb motor impairment in either the PNS or usual-care groups. However, both the PNS and usual-care groups demonstrated significant improvements in functional mobility and quality of life during the treatment period, which were maintained at 6-month follow-up.

Comparison of articulated and rigid ankle-foot orthoses in children with cerebral palsy: a systematic review

PURPOSE

The aim of this review was to compare the effects of rigid and articulated ankle-foot orthoses on gait in children with cerebral palsy (CP).

METHOD

A systematic review was carried out in 4 databases. The papers identified were evaluated on the basis of the following inclusion criteria: (1) design--controlled clinical trial; (2) population--children and adolescents with CP; (3) intervention--rigid or articulated ankle-foot orthoses; and (4) outcome--improved motor function and gait performance.

RESULTS

Seven controlled studies comparing the effects of different ankle-foot orthoses were found. Studies achieved PEDro scores of 3 and 4 for methodological quality.

CONCLUSION

There is evidence supporting the use of an articulated ankle-foot orthosis by children with CP, because of the improved function this type of orthosis provides. However, other studies point out the advantages of a rigid orthosis for children with greater impairment related to spasticity and contractures.

Slip resistance of non-slip socks--an accelerometer-based approach

The present study investigated the relative slip resistance of commercially available non-slip socks during gait. Twenty-four healthy subjects (29.3±10.4 years) participated in the study. Each subject completed 4 different test conditions (barefoot, non-slip socks, conventional socks, backless slippers) in a randomized, balanced order. The slip resistance was estimated by measuring the heel deceleration time using a heel-mounted accelerometer. Repeated measures ANOVA and post hoc paired-sample t-test with Bonferroni correction were used for statistical analysis. Compared to barefoot walking absolute deceleration times [ms] were significantly increased when wearing conventional socks or slippers. No significant differences were observed between the barefoot and non-slip socks conditions. The present study shows that non-slip socks improved slip-resistance during gait when compared to conventional socks and slippers. Future investigations should verify the present findings in hospital populations prone to slip-related falls.

Tibialis anterior tendon shortening in combination with Achilles tendon lengthening in spastic equinus in cerebral palsy

Equinus is the commonest deformity in cerebral palsy (CP). Many different surgical procedures have been described for the treatment of spastic equinus. In long standing equinus deformities the tibialis anterior muscle becomes elongated which is one reason for muscle weakness. Surgical tendon shortening of the tibialis anterior tendon was therefore introduced to rebalance muscle strength. All patients with CP who had a tibialis anterior tendon shortening (TATS) in combination with a tendo Achilles lengthening (TAL) were included in this study. A total of 29 patients had 30 surgical interventions (21 hemiplegic patients: 14 boys/7 girls, age 9-22 years; mean 15.2 years; 5 diplegics and 3 quadriplegics; 5 boys/3 girls, age 7-37.5 years; mean 14.8 years). Fifteen patients had additional surgery (soft tissue or bony procedures). The TATS was performed at the distal insertion with transosseous tendon fixation in the medial cuneiform bone at the original place. Movement Analysis Profile (MAP) for ankle dorsi-/plantarflexion, Gait Profile Score (GPS), Gait Deviation Index (GDI), and Gillette Gait Index (GGI) improved significantly for all patients compared pre- to postoperatively. In 93% of the patients active dorsiflexion of the ankle was possible postoperatively. We conclude that TATS in combination with TAL in spastic equinus in CP is a safe procedure and improves but not completely corrects foot positioning during gait. For the treatment of spastic equinus in CP we recommend shortening of the elongated antagonist (TATS) in combination with lengthening of the short agonist (TAL) for achieving optimal postoperative function.

Normative EMG activation patterns of school-age children during gait

Gait analysis is widely used in clinics to study walking abnormalities for surgery planning, definition of rehabilitation protocols, and objective evaluation of clinical outcomes. Surface electromyography allows the study of muscle activity non-invasively and the evaluation of the timing of muscle activation during movement. The aim of this study was to present a normative dataset of muscle activation patterns obtained from a large number of strides in a population of 100 healthy children aged 6-11 years. The activity of Tibialis Anterior, Lateral head of Gastrocnemius, Vastus Medialis, Rectus Femoris and Lateral Hamstrings on both lower limbs was analyzed during a 2.5-min walk at free speed. More than 120 consecutive strides were analyzed for each child, resulting in approximately 28,000 strides. Onset and offset instants were reported for each observed muscle. The analysis of a high number of strides for each participant allowed us to obtain the most recurrent patterns of activation during gait, demonstrating that a subject uses a specific muscle with different activation modalities even in the same walk. The knowledge of the various activation patterns and of their statistics will be of help in clinical gait analysis and will serve as reference in the design of future gait studies.

A systematic review to determine best practice reporting guidelines for AFO interventions in studies involving children with cerebral palsy

Studies which have examined the effects of ankle-foot orthoses (AFOs) on children with cerebral palsy (CP) often report insufficient detail about the participants, devices and testing protocols. The aim of this systematic review was to evaluate the level and quality of detail reported about these factors in order to generate best practice guidelines for reporting of future studies. A systematic search of the literature was conducted to identify studies which examined any outcome measure relating to AFO use in children with CP. A customized checklist was developed for data extraction and quality assessment. There was substantial variability in the level and quality of detail reported across the 41-paper yield. Many papers reported insufficient detail to allow synthesis of outcomes across studies. The findings of this review have been used to generate guidelines for best practice of reporting for AFO intervention studies. It is important to ensure homogeneity of gait pattern in a subject sample or to subdivide a sample to investigate the possibility that heterogeneity affected results. It is also important to describe the orthosis in sufficient detail that the device can be accurately replicated because differences in designs have been shown to affect outcomes. These guidelines will help researchers provide more systematic and detailed reports and thereby permit future reviewers to more accurately assess both the reporting and quality of orthotic interventions, and will facilitate synthesis of literature to enhance the evidence base.

Dynamic splinting home therapy for toe walking: a case report

Serial casting is frequently prescribed for toe-walking but that does not allow continued physical therapy (PT). This report described a child and family who chose dynamic splinting (DS) with concurrent PT for treatment. The patient presented with right hemiparesis; below average motor skills and a gait pattern of toe contact (without ankle foot orthosis). Four months of PT plus 6 hours/night of DS as home therapy, the patient's passive dorsiflexion increased 14° and she gained the ability to walk in "flat foot" contact without the Ankle Foot Orthosis. This concurrent treatment achieved improved gait pattern and strength training not possible with casting.

Recovery of Gait After Stroke: What Changes?

Background. Little is known about whether changes in coordination patterns of muscle activation after stroke are related to functional recovery of walking. Objective . The present study investigated the longitudinal relationship between changes in neuromuscular activation patterns of paretic muscles in hemiplegic gait and improvement in walking ability after stroke. Methods. Thirteen patients diagnosed with a first unilateral ischemic stroke had their recovery of walking measured by the Rivermead Mobility Index, Functional Ambulation Categories, Barthel Index, Trunk Control Test, Motricity Index, and comfortable walking speed. Surface electromyography (SEMG) of the erector spinae, gluteus maximus, gluteus medius, rectus femoris, vastus lateralis, semitendinosus, gastrocnemius, and tibialis anterior muscles of both legs was used to quantify coordination patterns in comfortable walking mode. All clinical and electromyography-related measurements were taken at 3, 6, 9, 12, and 24 weeks poststroke. Timing parameters of the SEMG patterns were calculated, using an objective burst detection algorithm, and analyzed with the measures of functional recovery. Results . All functional measures, except Trunk Control Test, showed statistically significant improvement over time, whereas SEMG patterns did not change significantly over time. Conclusion. The lack of significant change in SEMG patterns over time suggests that functional gait improvements may be more related to compensatory strategies in muscle activation of the unaffected leg and biomechanical changes than by restitution of muscle coordination patterns in the affected leg.

Electromyographic patterns in children with cerebral palsy: do they change after surgery?

The purpose of this study was to investigate the changes in electromyographic (EMG) patterns after multilevel surgical treatment in children with spastic cerebral palsy. Children with diplegia (n=18) and hemiplegia (n=16) aging from 6 to 16 years participated in the study. Twenty healthy children within the same age span are presented as reference. Gait analysis and surface electromyograms of seven major lower limb muscles were assessed before and 1-5 years after the multilevel surgery. The most frequent procedures were equinus correction, distal rectus femoris transfer, femoral derotation osteotomy and hamstrings lengthening. The results showed that the EMG pattern of the soleus, lateral gastrocnemius and tibialis anterior muscles became closer to normal after the surgery, while no differences were detected between diplegic and hemiplegic patients. Furthermore, a subgroup of 10 patients showed an increase in medial hamstrings activation during preswing that decreased postoperatively. These findings indicate that changes in EMG patterns should not be ruled out after surgical treatment, although the extent of these changes is limited compared to changes in the kinematics. Abnormal muscle activation before the operation can be related to a compensatory response in some patients and this can be manipulated after surgery.