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Objectives: As a step towards the comprehensive evaluation of movement in patients with low back pain, the aim of this study is to design a marker set (three rigid segment spine, pelvic and lower limb model) and evaluate the reliability and minimal detectable change (MDC) of this marker set in healthy adults during gait and sit to stand (STS) tasks using three dimensional motion capture., Results: The 'Imperial Spine' marker set was used to assess relative peak angles during gait and STS tasks using the minimum recommended sample size (n = 10) for reliability studies with minimum Intraclass Correlation Coefficient (ICC) of 0.70, optimum ICC 0.90 and 9 trials replicated per subject per task. Intra- and inter-tester reliability between an experienced and inexperienced user was examined. ICC, mean, standard error (SEM), Bland Altman 95% limits of agreement (LOA) and MDC were computed. ICC values demonstrated excellent intra- and inter-tester reliability in both tasks, particularly in the sagittal plane (majority ICCs > 0.80). SEM measurements were lower in gait (0.8-5.5°) than STS tasks (1°-12.6°) as were MDC values. LOA demonstrated good agreement. The 'Imperial Spine' marker set is reliable for use in healthy adults during functional tasks. Future evaluation in patients is required.

Background: Gait analysis plays an important role in the diagnosis and management of patients with movement disorders but it is usually performed within a laboratory. Recently interest has shifted towards the possibility of conducting gait assessments in everyday environments thus facilitating long-term monitoring. This is possible by using wearable technologies rather than laboratory based equipment., Research Question: This study aims to validate a novel wearable sensor system's ability to measure peak knee sagittal angles during gait., Methods: The proposed system comprises a flexible conductive polymer unit interfaced with a wireless acquisition node attached over the knee on a pair of leggings. Sixteen healthy volunteers participated to two gait assessments on separate occasions. Data was simultaneously collected from the novel sensor and a gold standard 10 camera motion capture system. The relationship between sensor signal and reference knee flexion angles was defined for each subject to allow the transformation of sensor voltage outputs to angular measures (degrees). The knee peak flexion angle from the sensor and reference system were compared by means of root mean square error (RMSE), absolute error, Bland-Altman plots and intra-class correlation coefficients (ICCs) to assess test-retest reliability., Results: Comparisons of knee peak flexion angles calculated from the sensor and gold standard yielded an absolute error of 0.35(±2.9°) and RMSE of 1.2(±0.4)°. Good agreement was found between the two systems with the majority of data lying within the limits of agreement. The sensor demonstrated high test-retest reliability (ICCs>0.8)., Significance: These results show the ability of the sensor to monitor knee peak sagittal angles with small margins of error and in agreement with the gold standard system. The sensor has potential to be used in clinical settings as a discreet, unobtrusive wearable device allowing for long-term gait analysis., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: Gait is affected in women with pelvic girdle pain (PGP), a musculoskeletal condition affecting 20% of pregnant women. Whilst there is evidence of spatiotemporal changes in gait during healthy pregnancy, less is known in relation to women with PGP. Appreciating gait characteristics during healthy pregnancy could inform our understanding of the role of gait in PGP., Purpose: The purpose of this review was to systematically analyse differences in the spatiotemporal parameters of gait in healthy pregnant women and those with PGP, and to make recommendations to improve research methods in investigating gait in PGP women., Methods: The review was undertaken following the PRISMA guidelines. Three databases and pre-existing literature were electronically and manually searched. Study selection and data extraction were conducted by two reviewers. Quality assessment was performed using the NHLBI tool for Observational Cohort and Cross-sectional Studies., Results: The search returned 2925 results. Fourteen studies were selected for data extraction. Twelve studies investigated gait in healthy pregnant women and two in PGP women. Studies employed either a cohort or cross-sectional design and used various methods to assess gait. Three, nine and two studies were high, medium and low in quality, respectively. Direct comparisons between studies were impeded due to incomparable gestational time-points investigated, in addition to variations in gait parameters and definitions used., Conclusion: Evidence from studies on healthy pregnant women could inform future research on PGP women, for which current evidence is scarce. We recommend the standardisation of critical factors to allow inter-study comparisons for a meta-analysis.

The relationship between age and gait characteristics in people with and without medial compartment osteoarthritis (OA) remains unclear. We aimed to characterize this relationship and to relate biomechanical and structural parameters in a subset of OA patients. Twenty five participants with diagnosed unilateral medial knee OA and 84 healthy participants, with no known knee pathology were recruited. 3D motion capture was used to analyse sagittal and coronal plane gait parameters while participants walked at a comfortable speed. Participants were categorized according to age (18-30, 31-59 and 60+ years), and those with and without OA were compared between and within age groups. In a subset of OA patients, clinically available Computed Tomography images were used to assess joint structure. Differences in coronal plane kinematics at the hip and knee were noted in participants with OA particularly those who were older compared with our healthy controls, as well as increased knee moments. Knee adduction moment correlated with structural parameters in the subset of OA patients. Increased knee moments and altered kinematics were observed in older participants presenting with OA only, which seem to be related to morphological changes in the joint due to OA, as opposed to being related to the initial cause of medial knee OA., (Copyright © 2017. Published by Elsevier B.V.)

Background: Individuals who suffered a lower limb injury have an increased risk of developing knee osteoarthritis. Early diagnosis of osteoarthritis and the ability to track its progression is challenging. This study aimed to explore links between self-reported knee osteoarthritis outcome scores and biomechanical gait parameters, whether self-reported outcome scores could predict gait abnormalities characteristic of knee osteoarthritis in injured populations and, whether scores and biomechanical outcomes were related to osteoarthritis severity via Spearman's correlation coefficient., Methods: A cross-sectional study was conducted with asymptomatic participants, participants with lower-limb injury and those with medial knee osteoarthritis. Spearman rank determined relationships between knee injury and outcome scores and hip and knee kinetic/kinematic gait parameters. K-Nearest Neighbour algorithm was used to determine which of the evaluated parameters created the strongest classifier model., Findings: Differences in outcome scores were evident between groups, with knee quality of life correlated to first and second peak external knee adduction moment (0.47, 0.55). Combining hip and knee kinetics with quality of life outcome produced the strongest classifier (1.00) with the least prediction error (0.02), enabling classification of injured subjects gait as characteristic of either asymptomatic or knee osteoarthritis subjects. When correlating outcome scores and biomechanical outcomes with osteoarthritis severity only maximum external hip and knee abduction moment (0.62, 0.62) in addition to first peak hip adduction moment (0.47) displayed significant correlations., Interpretation: The use of predictive models could enable clinicians to identify individuals at risk of knee osteoarthritis and be a cost-effective method for osteoarthritis screening., (Copyright © 2017. Published by Elsevier Ltd.)

Objective: To evaluate intra- and inter-session reliability of gait data in hypermobile and normal adults, and from this, determine the minimum detectable change (MDC) through 3D gait analysis (GA) measurement., Methods: Thirteen people with normal flexibility (Beighton score 0.82 ± 1.2) and 14 hypermobile people (Beighton score 5.6 ± 1.6) completed three separate GA sessions. Lower limb joint kinematics were recorded in three planes of motion. Intra- and inter-session variability was calculated and compared using single factor ANOVA. MDC at 95% confidence level was calculated for the hypermobile cohort., Results: There was no significant difference between hypermobile and normal flexibility adults in intra- or inter-session variability for any parameters measured. For both groups, mean intra-session variability was under 2.0° for all joints in all three planes. Inter-session variability was greater; sagittal plane joint angles were most reliable, showing less than 3.0° variability for all joints. Frontal plane variability was below 3.5°. Highest variability was seen in internal/external rotation angles, with hip, knee and ankle showing 4.6°, 5.1° and 3.2° variability respectively. These reliability values are reflected in MDC results, with pelvis and sagittal plane joint angles showing the lowest MDCs., Conclusions: In hypermobile people, 3DGA kinematic parameters are repeatable. Hypermobile people's joint laxity does not affect variability of their kinematic gait analysis measures. The results will help guide future clinical trial design; future work should ensure that differences expected to be observed are measurable, and exceed the MDC for a given parameter., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Gait adaptations in people with severe knee osteoarthritis (OA) have been well documented, with increased knee adduction moments (KAM) the most commonly reported parameter. Neuromuscular adaptations have also been reported, including reduced postural control. However these adaptations may be the result of morphological changes in the joint, rather than the cause. This study aimed to determine if people with early OA have altered gait parameters and neuromuscular adaptations. Gait and postural tasks were performed by 18 people with early medial knee OA and 18 age and gender-matched control subjects. Parameters measured were kinematics and kinetics during gait and postural tasks, and centre of pressure and electromyographic activity during postural tasks. OA subjects showed no differences in the gait parameters measured, however they demonstrated postural deficits during one-leg standing on both their affected and unaffected sides and altered hip adduction moments compared with controls. Increased activity of the gluteus medius of both sides (p<0.05), and quadriceps and hamstrings of the affected side (p<0.05) during one-leg standing compared with controls were also noted. This study has demonstrated that gait adaptations commonly associated with OA do not occur in the early stages, while neuromuscular adaptations are evident. These results may be relevant for early interventions to delay or prevent osteoarthritis in its early stages., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

Gait analysis is an important clinical tool. A variety of models are used for gait analysis, each yielding different results. Errors in model outputs can occur due to inaccurate marker placement and skin motion artefacts, which may be reduced using a cluster-based model. We aimed to compare a custom-made cluster model (ClusBB) with Vicon's plug-in gait. A total of 21 healthy subjects wore marker sets for the ClusBB and plug-in gait models simultaneously while walking on a 6-m walkway. Marker and force plate data were captured synchronously and joint angles/moments were calculated using both models. There was good correlation between the models (coefficient of multiple correlations > 0.65) and good intra-session correlation for both models (coefficient of multiple correlations > 0.80). Inter-subject variability was high, ranging from 15° to 40° in the sagittal plane and 11° to 52° in the coronal and transverse planes. Intra-subject variability was small for both ClusBB and plug-in gait models. Inter-subject variance tended to be high in both models for knee abduction/adduction, but particularly so for plug-in gait, suggesting that a cluster-based model may reduce the variability. The inter-subject variance in out-of-sagittal plane data is of particular importance clinically, given the reliance on these datasets in clinical decision-making.

Multiple marker sets and models are currently available for assessing pelvic kinematics in gait. Despite the presence of a variety models, there are still debates on their reliability and consistency, and consequently there is no clearly defined standard. Two marker sets were evaluated in this study: the 'Traditional' where markers are placed at the anterior and posterior superior iliac spines (ASISs, PSISs); and the 'Cluster', where a cluster of three orthogonal markers fixed on a rigid based is attached to the sacrum. The two sets were compared with respect to intra and inter session standard deviations of maximum pelvic tilt, obliquity and rotation angles. The repeatability between and within sessions was measured using coefficient of multiple correlation (CMC). Also the similarity between the two sets was assessed using inter-protocol CMC (ipCMC). Both data sets generated showed high within and between session repeatability in the sagittal plane (CMC>0.80), although the Cluster method showed higher repeatability than that of the Traditional method in non-sagittal plane motion for both within and between sessions. The authors are not aware of other studies reporting the differences in intra and inter session variability and repeatability values for different body mass index categories such as overweight and obese subjects with relatively large sample size. Hence the Cluster method overcomes a number of theoretical and experimental limitations such as minimising the marker occlusion and is a reliable alternative to the Traditional (the standard) marker set., (Copyright © 2013 Elsevier B.V. All rights reserved.)