Performance fatigability during gait in adults with Charcot-Marie-Tooth disease

BackgroundFatigue is common in people with Charcot-Marie-Tooth (pwCMT) disease. However, no studies have characterized performance fatigability during gait in this population. Characterizing performance fatigability during gait, and assessing its relation to life satisfaction could improve understanding and treatment of mobility challenges in pwCMT.Research questionsHow do gait outcomes change with fatigue in pwCMT? Do these changes relate to life satisfaction?Methods31 pwCMT completed a 6-minute, fast-as-possible walk while gait outcomes were captured via inertial sensors. Gait outcomes were separated into six sequential bins of equal size. The mean value, variability, and asymmetry (step time only) of outcomes were calculated for each bin. Perceived fatigue and general life satisfaction were assessed via questionnaire.ResultsOf the five mean gait outcomes measured, four showed statistically significant changes over the 6-minute fast-as-possible walk: velocity (reduced; p = 0.008); cadence (reduced; p < 0.001), step time (increased; p < 0.001), and trunk ROM (increased; p = 0.032). Of the four variability and one asymmetry outcomes, only stride length variability changed during the walking task (p = 0.015), decreasing from bins 1–2, and remaining stable for bins 2–6. Changes in velocity, cadence, step time were related to general life satisfaction (0.038 < ps<0.04), but not perceived fatigue (ps>0.343).SignificancepwCMT exhibit statistically significant changes in mean gait outcomes, but not variability outcomes, across a 6-minute, fast-as-possible walking bout. Changes correlated to life satisfaction, suggesting performance fatigability during gait could be a target for rehabilitation for pwCMT. Perceived fatigue did not correlate to gait fatigue, underscoring the differentiation between perceived fatigue and performance fatigability.     

Stance and swing phase ankle phenotypes in youth with Charcot-Marie-Tooth type 1: An evaluation using comprehensive gait analysis techniques

BackgroundCharcot-Marie-Tooth disease (CMT) results in muscle weakness and contracture leading to a wide variety of gait issues including atypical ankle kinematics in both stance and swing. Knowledge of the stance and swing phase kinematic patterns for CMT type 1 (CMT1), the most common CMT type, will improve our understanding of expected gait outcomes and treatment needs to improve gait function.Research questionWhat are the stance/swing phase ankle phenotypes in CMT1?MethodsA prospective convenience sample of 25 participants with CMT1, ages 7–19 years, underwent comprehensive gait analysis following standard procedures. Ankle phenotypes based on peak ankle dorsiflexion in terminal stance and mid-swing were defined and compared using linear mixed models.ResultsPatients with CMT1 presented with three stance phase ankle phenotypes: 21 limbs (42 %) with reduced (mean 5°, SD 2°), 19 limbs (38 %) with typical (mean 11°, SD 1°) and 10 limbs (20 %) with excessive (mean 15°, SD 2°) peak dorsiflexion in terminal stance (p < 0.05). There were two swing phase phenotypes: 19 limbs (38 %) with typical (mean −1.7°, SD 1.5°) and 31 limbs (62 %) with excessive (mean −5.6°, SD 1.4°) plantarflexion in mid-swing (p < 0.002). Eleven patients (44 %) had ankles that were classified into different stance groups, and 9 patients (36 %) had ankles that were classified into different swing groups. The most common combination of stance/swing ankle phenotypes was decreased dorsiflexion in terminal stance with increased plantarflexion in mid-swing (16 sides, 32 %).SignificanceThis study shows that youth with CMT1 have multiple combinations of combined ankle kinematics for stance and swing. The ankle phenotypes identified in this study reflect contributions of both dorsi/plantarflexor weakness and plantarflexor contracture, which require different treatment approaches. Comprehensive gait analysis can distinguish between multiple ankle phenotypes to assist in determining the most appropriate treatment to improve gait for individual patients.     

Comparison of gait patterns and functional measures between Charcot-Marie-Tooth disease type I and II in children to young adults

IntroductionCharcot-Marie-Tooth (CMT) disease is an inherited peripheral neuropathy that causes progressive distal extremity nerve degeneration and muscle atrophy which can negatively impact function, gait and quality of life. The purpose of this study was to determine if differences exist in gait patterns, clinical examination and functional measures between CMT type I (CMT1) and type II (CMT2) in childhood to young adults. It was hypothesized that individuals with CMT2 would present with greater ankle weakness, increased and/or prolonged ankle dorsiflexion in stance during gait and demonstrate greater disease severity on the CMT Pediatric Scale (CMTPedS) compared to CMT1.MethodsTwenty-seven individuals diagnosed with CMT1 or CMT2 underwent three-dimensional gait analysis, clinical examination and evaluation of disease severity using the CMTPedS. Subjects groups were divided based on CMT type: CMT1 (n = 20) and CMT2 (n = 7).ResultsCMT2 group presented with a trend towards increased plantar flexion weakness compared to CMT1 of 61.1 ± 58.1 N to 137.9 ± 51.4 N (p < 0.012), respectively. CMT2 presented with significantly decreased dorsiflexion strength, 31.9 ± 30.9 N, compared to CMT1, 80.4 ± 37.4 N, (p < 0.0052) which negatively influenced gait patterns in CMT2. Associated gait findings demonstrated CMT2 group with significantly decreased peak ankle power generation in stance compared to CMT1 (1.46 ± 0.39 W/kg to 3.13 ± 0.98 W/kg respectively) (p < 0.0001). CMT1 was more likely to demonstrate a dorsiflexion moment in loading response than CMT2. There was a consistent trend of a higher score and therefore greater disease severity for CMT2 based on CMTPedS.ConclusionStudy results suggest that at a given age, individuals with CMT2 have greater limitations in terms of gait function and disease severity than individuals with CMT1. Overall the CMT2 was shown to have greater gait limitations at the ankle during stance and swing with associated compensatory mechanisms at the knee and hip in swing.     

Gait patterns of children and adolescents with Charcot-Marie-Tooth disease

Gait abnormalities reported in childhood Charcot-Marie-Tooth disease (CMT) include foot-drop, reduced ankle power at push-off and increased knee and hip flexion for swing clearance (‘steppage-gait’). The purpose of this study was to describe the gait patterns of 60 children aged 6–17 years with CMT (CMT_all) and distinguish differences based on functional weakness using the CMT Pediatric Scale (CMTPedS). Data were captured using Vicon Nexus system and compared to 50 healthy norms. Data were subdivided into three groups denoting increasing severity of dorsiflexion and plantarflexion weakness from the CMTPedS: no difficulty heel or toe walking (CMT_ND), difficulty heel walking (CMT_DH), difficulty toe and heel walking (CMT_DTH). Compared to healthy norms, CMT_all demonstrated significantly worse gait profile score, reduced ankle dorsiflexion during swing (foot-drop), reduced ankle dorsiflexor moment in loading response and reduced external thigh-foot angle. Contrary to previous studies there were no signs of reduced ankle power or compensation through ‘steppage gait’ in this mild-moderately affected population. Instead, CMT_all demonstrated reduced internal hip rotation and reduced hip abductor moment. When data were sub-grouped and compared to healthy norms, three different gait patterns at the ankle emerged: CMT_ND had a near-normal gait pattern, CMT_DH presented with foot-drop, and CMT_DTH had increased peak dorsiflexion and reduced ankle power generation. Several distinct and abnormal gait patterns were identified in children with CMT, with increasing gait abnormalities in more functionally severe cases. Classifying gait patterns based on disease severity might be a valuable tool in clinical decision making, assessing disease progression and phenotype-genotype correlation studies.     

Full length foot orthoses have an immediate treatment effect and modify gait of children with idiopathic toe walking

BackgroundThere remains a substantial lack of evidence to support the use of foot orthoses as a conservative treatment option for idiopathic toe walking (ITW). Encouraging heel contact during gait is one of the primary goals of most interventions in paediatric ITW.Research QuestionDoes the combined treatment of high-top boots and orthoses increase the number of heel contacts during gait and change spatio-temporal gait parameters?MethodsThis within subject designed randomised controlled trial recruited fifteen children diagnosed with ITW (n = 10 males). They were fitted with bilateral custom made rigid contoured carbon fibre foot orthoses placed inside high-top boots. To analyze the effect of this treatment, heel contacts and spatio-temporal parameters measured by an 8.3 m Gaitrite® mat were compared to barefoot walking and shod walking.ResultsAn immediate increase in heel contact (p = 0.021) was observed in the combined treatment only. Gait changes included a large increase in stride time in the combined treatment condition compared to barefoot walking (p = 0.006). This was associated with a decrease in the percentage of swing phase in the gait cycle (p < 0.010), an increase in stance phase (p < 0.010) and an increase in double support time (p < 0.001).SignificanceThese results suggest the hardness and thickness of the shoe and stiffness of the orthosis midsole may lead to improved local dynamic stability and foot position awareness with increased sensory feedback provided through the entire length of the foot. Further research is indicated to validate this treatment option on long term outcomes in this population group.     

Analysis of gait symmetry during over-ground walking in children with autism spectrum disorder

Gait symmetry is utilized as an indicator of neurologic function. Healthy gait often exhibits minimal asymmetries, while pathological gait exhibits exaggerated asymmetries. The purpose of this study was to examine symmetry of mechanical gait parameters during over-ground walking in children with Autism Spectrum Disorder (ASD). Kinematic and kinetic data were obtained from 10 children (aged 5–12 years) with ASD. The Model Statistic procedure (α = 0.05) was used to compare gait related parameters between limbs. Analysis revealed children with ASD exhibit significant lower extremity joint position and ground reaction force asymmetries throughout the gait cycle. The observed asymmetries were unique for each subject. These data do not support previous research relative to gait symmetry in children with ASD. Many individuals with ASD do not receive physical therapy interventions, however, precision medicine based interventions emphasizing lower extremity asymmetries may improve gait function and improve performance during activities of daily living.     

Immediate effects of foot orthoses on lower limb biomechanics,pain, and confidence in individuals with patellofemoral osteoarthritis

BackgroundFoot orthoses are a recommended treatment for patellofemoral (PF) pain and a number of lower limb osteoarthritic (OA) conditions. However, their mechanism of effect is poorly understood.Research questionTo compare the immediate effects of foot orthoses and flat inserts on lower limb biomechanics, knee pain and confidence in individuals with PFOA.MethodsTwenty-one participants (14 females; mean ± SD age 58 ± 8 years) with PFOA underwent three-dimensional motion analysis during level-walking, stair ascent, and stair descent under three footwear conditions: (i) their own shoes; (ii) prefabricated foot orthoses; and (iii) flat shoe inserts. Participants reported their average levels of knee pain and confidence after each task. Data were analysed with repeated-measures analysis of variance (ANOVA), effect sizes (partial eta squared), and Bonferroni post-hoc tests.ResultsDuring level-walking, there was a significant main effect of foot orthoses on peak ankle dorsiflexion angle (F₂ = 0.773, p < 0.001, ƞ² = 0.773) and peak ankle external dorsiflexion moment (F₂ = 0.356, p = 0.046, ƞ² = 0.356). Foot orthoses decreased the peak ankle dorsiflexion angle compared to the flat insert and shoe conditions, and decreased the peak ankle external dorsiflexion moment relative to flat inserts. During stair descent, there was a significant main effect of foot orthoses on peak ankle external dorsiflexion moment (F₂ = 0.823, p = 0.006, ƞ² = 0.738), with a trend towards lower peak dorsiflexion moment for foot orthoses compared to the flat insert and shoe conditions. No significant main effects were observed during stair ascent. No other lower limb biomechanical changes were observed across all three conditions. Knee pain and confidence scores were not significantly different across the three conditions.SignificancePrefabricated foot orthoses altered sagittal plane biomechanics of the ankle during level-walking and stair descent in individuals with PFOA. Further research is required to determine whether these changes are clinically beneficial.     

An extended index to quantify normality of gait in children

Clinical gait analysis aims to quantify and assess the mechanics of walking and identify deviations from ‘normal’ movement patterns. To facilitate the use of clinical equipment, protocols are required to process data and produce a few meaningful summary measurements which can, in turn, be used to flag gait abnormalities. Earlier work produced a one-dimensional index of gait, calculated from sagittal hip, knee and ankle rotation angle patterns. The objective of this study was to extend the original index, incorporating kinematic and kinetic data from multiple planes, while allowing for correlations between component measures. A one-dimensional index of normal gait was developed, based on normative gait data (N = 45 children, aged 3–13 years). The new one-dimensional index was calculated using correlation patterns between seven component indices, each of which has diagnostic interpretation. The effectiveness of the new index was tested using immature normative data (N = 14) and hypotonic data (N = 10). Approximately 85% of immature normative children and 100% of hypotonic children were classified as either unusual or extreme by the one-dimensional index. These data reduction protocols improve objective gait analyses in the clinical setting.     

Replicating and redesigning ankle-foot orthoses with 3D printing for children with Charcot-Marie-Tooth disease

BackgroundChildren with the most common inherited neuropathy, Charcot-Marie-Tooth disease (CMT), are often prescribed ankle-foot orthoses (AFOs) to improve walking ability and prevent falls by reducing foot drop, postural instability, and other gait impairments. These externally worn assistive devices are traditionally custom-made using thermoplastic vacuum forming. This labour-intensive manufacturing process often results in AFOs which are cumbersome due to limited design options, and are associated with low acceptability, discomfort, and suboptimal impact on gait. The aim of this study was to determine how 3D printing can be used to replicate and redesign AFOs in children with CMT.MethodsTraditional AFOs, 3D printed replica AFOs (same design as traditional AFOs), 3D printed redesigned AFOs and a shoes only control condition were compared in 12 children with CMT. 3D printed AFOs were manufactured using material extrusion in Nylon-12. 3D gait analysis (temporal-spatial, kinematic, kinetic), in-shoe pedobarography and self-reported satisfaction were used to compare conditions. The primary kinematic and kinetic outcome measures were maximum ankle dorsiflexion in swing and maximum ankle dorsiflexor moment in loading response, to capture foot drop and an absent of heel rocker.ResultsThe 3D printed replica AFOs were comparable to traditional AFOs for all outcomes. The 3D printed replica AFOs improved foot position at initial contact and during loading response and significantly reduced pressure beneath the whole foot, rearfoot and forefoot compared to the shoes only. The 3D printed redesigned AFOs produced a device that was significantly lighter (mean −35.2, SD 13.3%), and normalised maximum ankle dorsiflexor moment in loading response compared to shoes only and traditional AFOs.Significance3D printing can be used to replicate traditional handmade AFOs and to redesign AFOs to produce a lighter device with improved biomechanics by incorporating novel design features.     

Quantitative comparison of five current protocols in gait analysis

Data collection and reduction procedures, coherently structured in protocols, are necessary in gait analysis to make kinematic and kinetic measurements clinically comprehensible. The current protocols differ considerably for the marker-set and for the biomechanical model implemented. Nevertheless, conventional gait variables are compared without full awareness of these differences. A comparison was made of five worldwide representative protocols by analysing kinematics and kinetics of the trunk, pelvis and lower limbs exactly over the same gait cycles. A single comprehensive arrangement of markers was defined by merging the corresponding five marker-sets. This resulted in 60 markers to be positioned either on the skin or on wands, and in 16 anatomical landmark calibrations to be performed with an instrumented pointer. Two healthy subjects and one patient who had a special two degrees of freedom knee prosthesis implanted were analysed. Data from up-right posture and at least three gait repetitions were collected. Five corresponding experts participated in the data collection and analysed independently the data according to their own procedures. All five protocols showed good intra-protocol repeatability. Joint flexion/extension showed good correlations and a small bias among protocols. Out-of-sagittal plane rotations revealed worse correlations, and in particular knee abduction/adduction had opposite trends. Joint moments compared well, despite the very different methods implemented. The abduction/adduction at the prosthetic knee, which was fully restrained, revealed an erroneous rotation as large as 30 degrees in one protocol. Higher correlations were observed between the protocols with similar biomechanical models, whereas little influence seems to be ascribed to the marker-set.     

Spatio-temporal parameters and lower-limb kinematics of turning gait in typically developing children

Turning is a requirement for most locomotor tasks; however, knowledge of the biomechanical requirements of successful turning is limited. Therefore, the aims of this study were to investigate the spatio-temporal and lower-limb kinematics of 90° turning. Seventeen typically developing children, fitted with full body and multi-segment foot marker sets, having performed both step (outside leg) and spin (inside leg) turning strategies at self-selected velocity, were included in the study. Three turning phases were identified: approach, turn, and depart. Stride velocity and stride length were reduced for both turning strategies for all turning phases (p < 0.03 and p < 0.01, respectively), while stance time and stride width were increased during only select phases (p < 0.05 and p < 0.01, respectively) for both turn conditions compared to straight gait. Many spatio-temporal differences between turn conditions and phases were also found (p < 0.03). Lower-limb kinematics revealed numerous significant differences mainly in the coronal and transverse planes for the hip, knee, ankle, midfoot, and hallux between conditions (p < 0.05). The findings summarized in this study help explain how typically developing children successfully execute turns and provide greater insight into the biomechanics of turning. This knowledge may be applied to a clinical setting to help improve the management of gait disorders in pathological populations, such as children with cerebral palsy.     

Immediate and 1 week effects of laterally wedge insoles on gait biomechanics in healthy females

It is estimated that approximately 45% of the U.S. population will develop knee osteoarthritis, a disease that creates significant economic burdens in both direct and indirect costs. Laterally wedged insoles have been frequently recommended to reduce knee abduction moments and to manage knee osteoarthritis. However, it remains unknown whether the lateral wedge will reduce knee abduction moments over a prolonged period of time. Thus, the purposes of this study were to (1) examine the immediate effects of a laterally wedged insole in individuals normally aligned knees and (2) determine prolonged effects after the insole was worn for 1 week. Gait analysis was performed on ten women with and without a laterally wedged insole. After participants wore the wedges for a week, a second gait analysis was performed with and without the insole. The wedged insole did not affect peak knee abduction moment, although there was a significant increase in knee abduction angular impulse after wearing the insoles for 1 week. Furthermore, there was a significant increase in vertical ground reaction force at the instance of peak knee abduction moment with the wedges. While the laterally wedged insole used in the current study did not alter knee abduction moments as expected, other studies have shown alterations. Future studies should also examine a longer acclimation period, the influence of gait speed, and the effect of different shoe types with the insole.     

Age and sex differences in normative gait patterns

BackgroundA comprehensive understanding of healthy gait patterns is a critical first step towards understanding age-related pathologies and disorders that are commonly associated with mobility limitations throughout aging. Further, consideration of sex-specific gait patterns throughout the lifespan is important, considering biological differences between males and females that can manifest biomechanically, and epidemiological evidence of female sex being a risk factor for some age-related pathologies such as osteoarthritis.Research questionThe aim of this study was to characterize the differences in lower extremity joint kinematics and kinetics during gait between asymptomatic adult women and men in different age groups (20–40 years, 41–50 years, 51–59 years, 60+ years).MethodsThis was a secondary analysis conducted on instrumented gait data from 154 asymptomatic adult participants (94 females, 60 males). Three-dimensional hip, knee and ankle joint angles and net external moments were calculated and waveform principal component analysis (PCA) was applied to extract major patterns of variability from each. PC scores were examined for significant sex, age and interaction effects using a two-factor ANOVA analysis (p = 0.001).Results13 PC features differed between asymptomatic male and female gait patterns, and were independent of age category. No PC features significantly differed between the age groups, and there were no significant sex by age interactions.SignificanceThere are significant magnitude and pattern differences in hip, knee and ankle kinematics and kinetics between asymptomatic women and men. As study participants were asymptomatic, these differences do not necessarily correlate with any injury or disease mechanisms. However, these results do suggest the importance of considering sex-specific analyses in gait study design, and the use of sex-specific normative data in clinical gait studies. These results further suggest that consideration of strict age-matching for gait analysis studies using adult controls is not as critical as sex considerations.     

Three-dimensional head and trunk movement characteristics during gait in children with spastic diplegia

This study uses a recently developed trunk model to determine which head and trunk kinematic parameters differentiate children with spastic diplegia from typically developing (TD) children while walking. Differences in head and trunk parameters in relation to the severity of the motor involvement (GMFCS levels) were additionally examined. The trunk model consisted of five segments (pelvis, thorax, head, shoulder line, spine). Discrete kinematic parameters (ROM, mean position) and angular waveforms were compared between 20 children with spastic diplegia (age 9.8 years ± 2.9 years; GMFCS I: n = 10, GMFCS II: n = 10) and 20 individually age-matched TD children (9.7 years ± 3 years). A new measure for overall trunk pathology, the trunk profile score (TPS), was proposed and included in the comparative analysis. Compared to TD children, children with GMFCS II showed a significantly higher TPS and increased ROM for pelvis tilt, for thorax and head in nearly all planes, and the angle of kyphosis. In children with GMFCS I, only ROM of thorax lateral bending was significantly increased. Sagittal ROM differentiated best between GMFCS levels, with higher ROM found in children with GMFCS II. Current results provide new insights into head and trunk kinematics during gait in children with spastic diplegia.     

Reliability and validity of the gait classification system in children with cerebral palsy (GCS-CP)

BackgroundGait classification systems (GCS) may enable clinicians to differentiate gait patterns into clinically significant categories that assist in clinical decision-making and assessment of outcomes. Davids and Bagley in 2014 [1] described a GCS for children with cerebral palsy (GCS-CP). The purpose of our study was to use the GCS-CP for the first time on a sample of patients with CP and to evaluate the reliability and utility of the classification system.MethodsThe gait of 131 children with CP was retrospectively reviewed and classified according to Davids and Bagley’s classification using two-dimensional (2D) video and three-dimensional (3D) lower limb kinematics and kinetics. Gross Motor Function Classification System (GMFCS) levels were determined, and the Gait Profile Scores (GPS) calculated to characterize the sample concerning gait classification. The comparison between the groups was performed using the Kruskal-Wallis test with respect to the non-normal distribution of the data. The intrarater and interrater reliability was determined using the Kappa index (k) statistics with 95% CI.ResultsAll GCS-CP groups were represented within the evaluated sample. Of the 131 cases evaluated, 127 (96.95%) were able to be classified with respect to sagittal plane stance phase gait deviations. All patients in the sample were able to be classified with respect to sagittal plane swing phase and transverse plane gait deviations. The interrater reliability was 0.596 and 0.485 for the first and second levels of the classification, respectively, according to the Fleiss’s Kappa statistics. Intrarater reliability was 0.776 and 0.714 for the raters one and two, respectively, according to the Cohen’s Kappa statistics.SignificanceThe GCS-CP exhibited clinical utility, successfully classifying almost all subjects with CP in two planes, based upon kinematic and kinetic data. The classification is valid and has moderate interrater and moderate to substantial intrarater reliability.     

Reliability and validity of knee angles and moments in patients with osteoarthritis using a treadmill-based gait analysis system

BackgroundAlthough commonly used to study knee osteoarthritis (OA), relatively little is known about the reliability and validity of three-dimensional (3D) gait biomechanics derived from treadmill-based systems.Research questionUsing a treadmill-based gait analysis system, our objectives were to: 1) estimate the test-retest reliability of frontal and sagittal plane knee angles and moments in knee OA patients; 2) examine concurrent validity by estimating the associations between treadmill-based and overground (gold standard) measures; and 3) examine known-groups validity by comparing measures between knee OA patients and matched healthy controls.Methods34 patients and 16 controls completed 3D gait analyses using treadmill-based and overground systems. Treadmill walking speed was matched to self-selected overground speed. Marker set, knee angle and moment calculations were consistent for both systems. Patients completed a second test session using the treadmill-based system <24 h later but within 1 week of the first test session. Variables calculated from knee angle and moment gait waveforms during stance were evaluated using Bland and Altman plots, Intraclass Correlation Coefficients (ICC), Pearson correlations (r) and t-tests.ResultsVisual inspection of the Bland and Altman plots did not reveal any systematic differences between test and retest sessions; however, limits of agreement (LoA) were larger for the sagittal plane than the frontal plane. Mean differences between sessions for knee angles were <0.25 degrees and <0.18 %BW*ht for knee moments. ICCs ranged from 0.57-to-0.93 for test-retest reliability. Pearson correlations between treadmill and overground systems ranged from 0.56-to-0.97. Although highly associated, there were substantial differences in the moments, emphasizing they cannot be used interchangeably. Patients had greater first peak knee adduction moments (KAM) than controls [mean difference (95 %CI): 0.55 (−1.07, −0.04), p = 0.03].SignificanceResults suggest frontal and sagittal plane knee angles and moments in patients with knee OA evaluated using a treadmill-based system are reliable and valid.     

Tibial impact accelerations in gait of primary school children: The effect of age and speed

Tibial stress fractures are associated with increased lower extremity loading at initial foot-ground contact, reflected in high peak positive acceleration (>8 g) of the tibia in adults. There is no reported data on peak positive acceleration of the tibia in children during walking and running. The aim of this study was to establish tibial peak positive acceleration responses in children across a range of age and gait speeds. Twenty-four children aged 8.5 ± 1.4 years with no known gait pathology comprised two age groups; Young (7–9 year, n = 12) and Older (10–12 years, n = 12). Wireless Inertial Measurement Unit comprising a tri-axial accelerometer was securely taped to the anteromedial aspect of the distal tibia to measure peak positive acceleration responses while walking and running on the treadmill at 3 different speeds (20% below baseline, baseline, and 20% above baseline). Results showed significant increase in peak positive acceleration with increased gait speed and greater variability in young children compared to older children. The study suggests that ground impact in walking, but not running, is mature by age 7 years. Future studies should explore strategies using peak positive acceleration responses to monitor ground impact during sport activities and its application in gait retraining.     

Single-session reliability of discrete gait parameters in ambulatory children with cerebral palsy based on GMFCS level

The single-session reliability of 28 discrete spatiotemporal and kinematic variables was evaluated from computerized gait analysis (CGA) in 33 ambulatory children with cerebral palsy (CP), subcategorized according to Gross Motor Function Classification System (GMFCS) Levels I (n = 11), II (n = 12) and III (n = 10). Nineteen boys and 14 girls participated, mean age = 8 years 1 month (S.D. = 3 years 0 month). Intraclass correlation coefficients (ICCs) estimated reliability, and the number of strides required to obtain an ICC of at least 0.90 was determined. The reliability of discrete gait parameters was dependent upon GMFCS level, with children in GMFCS Level I exhibiting the highest reliability (ICC range = 0.70–0.96). GMFCS Levels II and III had lower levels of reliability with ICC values varying from 0.54 to 0.95 and 0.45 to 0.98, respectively. With the exclusion of pelvis range of motion (ROM), an average of four strides provided a reliability estimate of at least 0.90 for GMFCS Level I, while six strides were needed for children in Levels II and III. On the basis of the intrasession reliability results from the present study, further work is recommended to examine the test–retest reliability of these gait parameters in children with CP.     

Effects of medially wedged insoles on the biomechanics of the lower limbs of runners with excessive foot pronation and foot varus alignment

BackgroundExcessive foot pronation during running in individuals with foot varus alignment may be reduced by medially wedged insoles.Research questionThis study investigated the effects of a medially wedged insole at the forefoot and at the rearfoot on the lower limbs angles and internal moments of runners with excessive foot pronation and foot varus alignment.MethodsKinematic and kinetic data of 19 runners (11 females and 8 males) were collected while they ran wearing flat (control condition) and medially wedged insoles (insole condition). Both insoles had arch support. We used principal component analysis for data reduction and dependent t-test to compare differences between conditions.ResultsThe insole condition reduced ankle eversion (p = 0.003; effect size = 0.63); reduced knee range of motion in the transverse plane (p = 0.012; effect size = 0.55); increased knee range of motion in the frontal plane in early stance and had earlier knee adduction peak (p = 0.018; effect size = 0.52); reduced hip range of motion in the transverse plane (p = 0.031; effect size = 0.48); reduced hip adduction (p = 0.024; effect size = 0.50); reduced ankle inversion moment (p = 0.012; effect size = 0.55); and increased the difference between the knee internal rotation moment in early stance and midstance (p = 0.012; effect size = 0.55).SignificanceInsoles with 7˚ medial wedges at the forefoot and rearfoot are able to modify motion and moments patterns that are related to lower limb injuries in runners with increased foot pronation and foot varus alignment with some non-desired effects on the knee motion in the frontal plane.     

Assessment of biomechanical deficits in individuals with a trans-tibial amputation during level gait using one-dimensional statistical parametric mapping

BackgroundMost previous studies reported biomechanical deficits in individuals with a trans-tibial amputation (TTA) during gait using zero-dimensional analyses. However, these analyses do not allow to precisely determine during which part of the gait cycle these deficits occur. There is a need to use more appropriate methods to map the differences, such as one-dimensional statistical parametric mapping.Research questionWhat are the most relevant phases of the gait cycle during which the biomechanical deficits in TTA occur?MethodsEight TTA and 15 healthy counterparts (CON) underwent one biomechanical gait analysis. Pelvis, hip, knee and ankle kinematics, total support moment (TSM) and gastrocnemius lateralis, vastus lateralis and tibialis anterior muscle activity were compared between the amputated (AmLL), the intact (InLL) and the control (CnLL) lower limbs using one-dimensional statistical parametric mapping.ResultsMore ankle dorsiflexion and knee flexion were observed for the AmLL compared to the InLL and CnLL (ankle only) from the end of the stance phase to the beginning of the swing phase. Less knee flexion was also found for the AmLL during early stance phase. More pelvis posterior tilt and rotation toward the contralateral limb was observed during most of the gait cycle for the AmLL compared to the InLL. TSM was smaller for the AmLL compared to the CnLL during early stance phase.SignificanceUsing a one-dimensional statistical parametric mapping approach for TTA gait analysis, this study provides novel insights on their biomechanical gait deficits compared to CON. Greater reliance on the InLL was observed in TTA as suggested by the asymmetric kinematic and kinetic profiles.