Stewart C. Morrison

Inter-rater reliability of the Foot Posture Index (FPI-6) in the assessment of the paediatric foot

BackgroundReliability is an integral component of clinical assessment and necessary for establishing baseline data, monitoring treatment outcomes and providing robust research findings. In the podiatric literature traditional measures of foot assessment have been shown to be largely unreliable. The Foot Posture Index (FPI-6) is a clinical tool used in the assessment of foot and to date, there is limited research published which evaluates the reliability of this tool in children and adolescents.MethodThirty participants aged 5 - 16 years were recruited for the research. Two raters independently recorded the FPI-6 score for each participant.ResultsAlmost perfect agreement between the two raters was identified following weighted kappa analysis (Kw = 0.86).ConclusionThe FPI-6 is a quick, simple and reliable clinical tool which has demonstrated excellent inter-rater reliability when used in the assessment of the paediatric foot.

Anthropometric foot structure of peripubescent children with excessive versus normal body mass: a cross-sectional study.

BACKGROUND A variety of musculoskeletal problems have been associated with excessive body mass in children, including structural foot problems. METHODS Two hundred children aged 9 to 12 years were recruited to evaluate the effect of body mass on foot structure. Three reliable anthropometric measures were recorded: foot length, forefoot width, and navicular height. RESULTS Following independent sample t test analysis of the data, significant differences were found for the three anthropometric variables when children with normal body mass were compared with those with excessive body mass. The research indicates that foot length and width increase with body mass, whereas navicular height drops. CONCLUSIONS Excessive body mass affects the discrete anthropometric structure of the peripubescent foot. With the growing concern about childhood obesity, further research is essential to develop a comprehensive understanding of the issues identified and to quantify the findings presented here.

The reliability of plantar pressure assessment during barefoot level walking in children aged 7-11 years

BackgroundPlantar pressure assessment can provide information pertaining to the dynamic loading of the foot, as well as information specific to each region in contact with the ground. There have been few studies which have considered the reliability of plantar pressure data and therefore the purpose of this study was to investigate the reliability of assessing plantar pressure variables in a group of typically developing children, during barefoot level walking.MethodsForty-five participants, aged 7 to 11 years, were recruited from local primary and secondary schools in East London. Data from three walking trials were collected at both an initial and re-test session, taken one week apart, to determine both the within- and between-session reliability of selected plantar pressure variables. The variables of peak pressure, peak force, pressure-time and force-time integrals were extracted for analysis in the following seven regions of the foot; lateral heel, medial heel, midfoot, 1st metatarsophalangeal joint, 2nd-5th metatarsophalangeal joint, hallux and the lesser toes. Reliability of the data were explored using Intra Class Correlation Coefficients (ICC 3,1 and 3,2) and variability with Coefficients of Variation (CoVs).ResultsThe measurements demonstrated moderate to good levels of within-session reliability across all segments of the foot (0.69-0.93), except the lesser toes, which demonstrated poor reliability (0.17-0.50). CoVs across the three repeated trials ranged from 10.12-19.84% for each of the measured variables across all regions of the foot, except the lesser toes which demonstrated the greatest variability within trials (27.15-56.08%). The between-session results demonstrated good levels of reliability across all foot segments (0.79-0.99) except the lesser toes; with moderate levels of reliability reported at this region of the foot (0.58-0.68). The CoVs between-sessions demonstrated that the midfoot (16.41-36.23%) and lesser toe region (29.64-56.61) demonstrated the greatest levels of variability across all the measured variables.ConclusionsThese findings indicate that using the reported protocols, reliable plantar pressure data can be collected in children, aged 7 to 11 years in all regions of the foot except the lesser toes which consistently reported poor-to-moderate levels of reliability and increased variability.

Evaluation of multi-segmental kinematic modelling in the paediatric foot using three concurrent foot models

BackgroundVarious foot models are used in the analysis of foot motion during gait and selection of the appropriate model can be difficult. The clinical utility of a model is dependent on the repeatability of the data as well as an understanding of the expected error in the process of data collection. Kinematic assessment of the paediatric foot is challenging and little is reported about multi-segment foot models in this population. The aim of this study was to examine three foot models and establish their concurrent test-retest repeatability in evaluation of paediatric foot motion during gait.Methods3DFoot, Kinfoot and the Oxford Foot Model (OFM) were applied concurrently to the right foot and lower limb of 14 children on two testing sessions. Angular data for foot segments were extracted at gait cycle events and peaks and compared between sessions by intraclass correlation coefficient (ICC) with 95% confidence intervals (95%CI) and standard error of measurement (SEM).ResultsAll foot models demonstrated moderate repeatability: OFM (ICC 0.55, 95% CI 0.16 to 0.77), 3DFoot (ICC 0.47, 95% CI 0.15 to 0.64) and Kinfoot (ICC 0.43, 95% CI -0.03 to 0.59). On the basis of a cut-off of 5°, acceptable mean error over repeated sessions was observed for OFM (SEM 4.61° ± 2.86°) and 3DFoot (SEM 3.88° ± 2.18°) but not for Kinfoot (SEM 5.08° ± 1.53°). Reliability of segmental kinematics varied, with low repeatability (ICC < 0.4) found for 14.3% of OFM angles, 22.7% of 3DFoot angles and 37.6% of Kinfoot angles. SEM greater than 5° was found in 26.2% of OFM, 15.2% of 3DFoot, and 43.8% of Kinfoot segmental angles.ConclusionFindings from this work have demonstrated that segmental foot kinematics are repeatable in the paediatric foot but the level of repeatability and error varies across the segments of the different models. Information on repeatability and test-retest errors of three-dimensional foot models can better inform clinical assessment and advance understanding of foot motion during gait.

Foot loading patterns in normal weight, overweight and obese children aged 7 to 11 years.

BackgroundChildhood obesity is thought to predispose to structural foot changes and altered foot function. Little is currently understood about whether similar changes occur in overweight children. The aim of this study was determine foot loading characteristics in obese, overweight and normal weight children aged 7 to 11 years during level walking.MethodsDynamic plantar pressures were measured in 22 obese, 22 overweight and 56 normal weight children recruited from local primary and secondary schools in East London. Peak pressure, peak force, normalised peak force, pressure–time and force-time integrals were analysed at six regions of the plantar foot: lateral heel, medial heel, midfoot, 1st metatarsophalangeal joint, 2nd-5th metatarsophalangeal joint and hallux. A one-way ANOVA was used to test for significant differences in variables across the groups. Where differences existed Tukey post-hoc tests were used to ascertain the location of the difference.ResultsChildren who were obese and overweight demonstrated significantly (p<0.05) higher peak pressures and peak forces as well as significantly higher force-time and pressure–time integrals under the midfoot and 2nd-5th metatarsal regions. After normalisation of peak force, similar trends existed where the obese and overweight children demonstrated significantly (p<0.05) greater loading at the midfoot and 2nd-5th metatarsals.ConclusionFindings from this study indicated that overweight children, as young as seven, displayed differences in foot loading during walking, when compared with normal weight children. These findings were consistent with loading patterns of children who were obese and suggest that early assessment and intervention may be required in overweight children to mitigate against the development of musculoskeletal complications associated with excessive body mass.

Assessment of gait characteristics and orthotic management in children with Developmental Coordination Disorder: Preliminary findings to inform multidisciplinary care

Developmental Coordination Disorder (DCD) is a neurodevelopmental disorder characterised by impaired motor co-ordination and awkward gait. Despite self-reported findings of pes planus and joint hypermobility in children with DCD, there is little objective evidence regarding the clinical management of the foot in children with DCD. The aims of this research were to report clinical findings of foot posture and lower limb hypermobility in children with DCD and to evaluate the impact of foot orthoses on spatio-temporal gait parameters. Children with DCD were recruited into the study. Participants were randomly assigned to an intervention group who received foot orthoses at the start of their rehabilitation programme or to a second group who received foot orthoses at the end of their intervention programme. Foot posture was assessed with the Foot Posture Index and lower limb hypermobility assessed with the Lower Limb Assessment Score. The effect of foot orthoses was evaluated through assessment of spatio-temporal gait characteristics at baseline and post-rehabilitation programme. Fourteen children were recruited (mdn age 7.5 years) with nine children assigned to the group receiving orthoses early (mdn age 8 years) and five children assigned to the post-rehabilitation orthoses group (mdn age 6.5 years). A pes planus foot posture (FPI score=8) and lower limb hypermobility (LLAS score=11) were observed. Changes in spatio-temporal gait parameters failed to reach significance (p>.012) following orthotic invention but demonstrated a trend towards a decreased cadence and increased double support duration. Despite non-significant findings this work offers preliminary support for podiatric intervention in the rehabilitation of children with DCD. Further work is required to understand the biomechanics of gait in children with DCD and appreciate the role of podiatry as a component of multidisciplinary care.

Are spatiotemporal gait characteristics reliable outcome measures in children with developmental coordination disorder

Purpose: To evaluate the reliability of spatiotemporal gait parameters used in the clinical evaluation of children with developmental coordination disorder (DCD). Methods: Participants recruited were asked to ambulate across a 4.5-meter GAITRite walkway (CIR Systems, Inc, Havertown, Pennsylvania) at a self-selected walking speed. The spatiotemporal parameters recorded for both limbs were: velocity (cm/sec), stance phase duration (%), swing phase duration (%), stride length (cm), double support duration (%), and single support duration (%). Results: Intraclass correlation coefficient values attained in this study ranged from 0.24 to 0.73, with good reliability achieved for one parameter (cadence = 0.73), and moderate reliability for step length (0.55–0.58), stride length (0.57–0.61), and double support duration (0.56–0.59). Conclusion: The findings from this study indicate that the clinical evaluation of spatiotemporal gait parameters in children with DCD can yield reliable data for some parameters but further work on this is warranted.

Prediction of Anthropometric Foot Characteristics in Children

BACKGROUND The establishment of growth reference values is needed in pediatric practice where pathologic conditions can have a detrimental effect on the growth and development of the pediatric foot. This study aims to use multiple regression to evaluate the effects of multiple predictor variables (height, age, body mass, and gender) on anthropometric characteristics of the peripubescent foot. METHODS Two hundred children aged 9 to 12 years were recruited, and three anthropometric measurements of the pediatric foot were recorded (foot length, forefoot width, and navicular height). RESULTS Multiple regression analysis was conducted, and coefficients for gender, height, and body mass all had significant relationships for the prediction of forefoot width and foot length (P < or = .05, r > or = 0.7). The coefficients for gender and body mass were not significant for the prediction of navicular height (P > or = .05), whereas height was (P < or = .05). CONCLUSIONS Normative growth reference values and prognostic regression equations are presented for the peripubescent foot.

The impact of body fat on three dimensional motion of the paediatric foot during walking.

Childhood obesity is commonly associated with a pes planus foot type and altered lower limb joint function during walking. However, limited information has been reported on dynamic intersegment foot motion with the level of obesity in children. The aim of this study was to explore the relationships between intersegment foot motion during gait and body fat in boys age 7-11 years. Fat mass was measured in fifty-five boys using air displacement plethysmography. Three-dimensional gait analysis was conducted on the right foot of each participant using the 3DFoot model to capture angular motion of the shank, calcaneus, midfoot and metatarsals. Two multivariate statistical techniques were employed; principle component analysis reduced the multidimensional nature of gait analysis, and multiple linear regression analysis accounted for potential confounding factors. Higher fat mass predicted greater plantarflexion of the calcaneus during the first half and end of stance phase and at the end of swing phase. Greater abduction of the calcaneus throughout stance and swing was predicted by greater fat mass. At the midfoot, higher fat mass predicted greater dorsiflexion and eversion throughout the gait cycle. The findings present novel information on the relationships between intersegment angular motion of the foot and body fat in young boys. The data indicates a more pronated foot type in boys with greater body fat. These findings have clinical implications for pes planus and a predisposition for pain and discomfort during weight bearing activities potentially reducing motivation in obese children to be physically active.

Reliability of three foot models to examine paediatric gait

Background A variety of multi-segmental foot models have been produced to examine patterns of foot segmental movement during gait cycle to identify biomechanical differences between normal and pathological foot function[1-3]. The reliability of foot models to accurately describe motion of the foot joints is dependent on the ability of the examiner to repeatedly apply markers to specific landmarks and the relevance of models’ segmental descriptions to underlying anatomy. The aim of this study was to test the reliability of segmental angles measured by three published foot models during paediatric gait. Materials and methods Sixteen children, aged 6 to 12 years old, were recruited to the study. Marker sets for three foot models 3DFoot [1], Oxford Foot Model (OFM)[2], and Kinfoot[3] were applied to their right feet simultaneously which to the authors knowledge, is the first direct comparison of the three models during gait. Each foot model was assessed for repeatability of maximal joint angle and range of motion during the gait cycle between two testing occasions. Absolute angular differences and standard error of measurement (SEM) are reported. Results Repeatability of all maximal segmental angles and range of motions were higher in 3DFoot compared to OFM and Kinfoot (Table 1).