Non-memory subjective cognitive concerns predict incident motoric cognitive risk syndrome.

BACKGROUND AND PURPOSE: Motoric cognitive risk syndrome (MCR) is a predementia condition that combines slow gait and subjective cognitive concerns. As the earliest markers of MCR are relatively unknown, the role of subjective cognitive concerns was investigated to predict incident MCR in a well-characterized prospective cohort of non-demented older adults. METHODS: Non-demented MCR-free older adults (n = 476) from the Central Control of Mobility in Aging cohort completed gait, subjective cognition and neuropsychological assessment at baseline and follow-up. Subjective concerns were analyzed via responses to 12 items from three validated measures, the Late-Life Function and Disability Instrument - Disability Component, the Activities of Daily Living Prevention Instrument and the Geriatric Depression Scale, and were independent of items utilized to diagnose MCR. Cox proportional hazard models examined the association between cognitive concerns and incident MCR. RESULTS: After 2.36 ± 1.4 years, 28 participants developed MCR. Executive functioning (adjusted hazard ratio 2.458, 95% confidence interval 1.094-5.524, P = 0.029) and mental clarity concerns (adjusted hazard ratio 3.917, 95% confidence interval 1.690-9.077, P = 0.001) were associated with incident MCR, controlling for age, sex, education and gait speed. CONCLUSIONS: Subjective cognitive concerns in non-memory cognitive domains predict incident MCR. Although most MCR studies assess cognitive concerns about memory, our findings suggest the need to broaden the scope of subjective cognitive assessment to enhance the accuracy of diagnosis and prediction of future cognitive decline.

A systematic review and meta-analysis of the effect of an ankle-foot orthosis on gait biomechanics after stroke.

OBJECTIVE: To systematically review the evidence on the effects of an ankle-foot orthosis on gait biomechanics after stroke. DATA SOURCES: The following databases were searched; AMED, CINHAL, Cochrane Library (Stroke section), Medline, PubMed, Science Direct and Scopus. Previous reviews, reference lists and citation tracking of the selected articles were screened and the authors of selected trials contacted for any further unpublished data. REVIEW METHODS: Controlled trials of an ankle-foot orthosis on gait biomechanics in stroke survivors were identified. A modified PEDro score evaluated trial quality; those scoring 4/8 or more were selected. Information on the trial design, population, intervention, outcomes, and mean and standard deviation values for the treatment and control groups were extracted. Continuous outcomes were pooled according to their mean difference and 95% confidence intervals in a fixed-effect model. RESULTS: Twenty trials involving 314 participants were selected. An ankle-foot orthosis had a positive effect on ankle kinematics (P < 0.00001-0.0002); knee kinematics in stance phase (P < 0.0001-0.01); kinetics (P = 0.0001) and energy cost (P = 0.004), but not on knee kinematics in swing phase (P = 0.84), hip kinematics (P < 0.18-0.89) or energy expenditure (P = 0.43). There were insufficient data for pooled analysis of individual joint moments, muscle activity or spasticity. All trials, except one, evaluated immediate effects only. CONCLUSIONS: An ankle-foot orthosis can improve the ankle and knee kinematics, kinetics and energy cost of walking in stroke survivors.

First steps: Parent health behaviours related to children's foot health.

Good foot health throughout childhood is important but remains poorly understood with few studies exploring this topic. The aim of this study was to define parents' knowledge, practices and health-related perceptions of children's feet. A qualitative design was adopted. Semi-structured, one-to-one interviews were carried out with parents of children aged five years and under, recruited from South East and North West of England. Interviews explored parents' views, beliefs and understanding of foot health in infancy and early childhood. Transcripts of the interviews were analysed using thematic analysis. Eighteen interviews were conducted. Seven themes were identified relating to (1) parents belief and knowledge about children's foot health; (2) how parents use and share foot health information; (3) activities for supporting foot health and development; (4) footwear choices, beliefs and influences; (5) the way they access health professionals; (6) the way they search for foot health information and (7) developing practice(s) to support parents. The study provides the first insight into how parents view foot health in early infancy and childhood. The findings highlight the key foot health beliefs important to parents, how they learn about and what influences their decision-making about caring for children's feet, the way parents receive and seek information, and how they access support for foot health concerns. The findings highlight the need for accurate, clear and consistent foot health messages, and the important role health professionals have in signposting parents towards reliable and informative sources on foot health.

A randomised controlled trial and cost-consequence analysis of traditional and digital foot orthoses supply chains in a National Health Service setting: application to feet at risk of diabetic plantar ulceration.

BACKGROUND: Diabetic foot ulceration is a considerable cost to the NHS and foot orthotic provision is a core strategy for the management of the people with diabetes and a moderate to high risk of foot ulceration. The traditional process to produce a custom-made foot orthotic device is to use manual casting of foot shape and physical moulding of orthoses materials. Parts of this process can be undertaken using digital tools rather than manual processes with potential advantages. The aim of this trial was to provide the first comparison of a traditional orthoses supply chain to a digital supply chain over a 6 month period. The trial used plantar pressure, health status, and health service time and cost data to compare the two supply chains. METHODS: Fifty-seven participants with diabetes were randomly allocated to each supply chain. Plantar pressure data and health status (EQ5D, ICECAP) was assessed at point of supply and at six-months. The costs for orthoses and clinical services accessed by participants were assessed over the 6 months of the trial. Primary outcomes were: reduction in peak plantar pressure at the site of highest pressure, assessed for non-inferiority to current care. Secondary outcomes were: reduction in plantar pressure at foot regions identified as at risk (> 200 kPa), cost-consequence analysis (supply chain, clinician time, service use) and health status. RESULTS: At point of supply pressure reduction for the digital supply chain was non-inferior to a predefined margin and superior (p < 0.1) to the traditional supply chain, but both supply chains were inferior to the margin after 6 months. Custom-made orthoses significantly reduced pressure for at risk regions compared to a flat control (traditional - 13.85%, digital - 20.52%). The digital supply chain was more expensive (+£13.17) and required more clinician time (+ 35 min). There were no significant differences in health status or service use between supply chains. CONCLUSIONS: Custom made foot orthoses reduce pressure as expected. Given some assumptions about the cost models we used, the supply chain process adopted to produce the orthoses seems to have marginal impact on overall costs and health status. TRIAL REGISTRATION: Retrospectively registered on ISRCTN registry (ISRCTN10978940, 04/11/2015).

Predicting lower limb joint kinematics using wearable motion sensors.

The aim of this study was to estimate sagittal plane ankle, knee and hip gait kinematics using 3D angular velocity and linear acceleration data from motion sensors on the foot and shank. We explored the accuracy of intra-subject predictions (i.e., where training and testing uses trials from the same subject) and inter-subject (where testing uses subjects different from the ones used for training) predictions, and the effect of loss of sensor data on prediction accuracy. Hip, knee and ankle kinematic data were collected using reflective markers. Simultaneously, foot and shank angular velocity and linear acceleration data were collected using small integrated accelerometers/gyroscope units. A generalised regression networks algorithm was used to predict the former from the latter. The best results were from intra-subject predictions, with very high correlations (0.93-0.99) and low mean absolute deviation (< or =2.3 degrees ) between measured kinematic joint angles and predicted angles. The inter-subject case produced poorer correlations (0.70-0.89) and larger absolute differences between measured and predicted angles, ranging from 4.91 degrees (left ankle) to 9.06 degrees (right hip). The angular velocity data added little to the accuracy of predictions and there was also minimal benefit to using sensor data from the shank. Thus, a wearable system based only on footwear mounted sensors and a simpler sensor set providing only acceleration data shows potential. Whilst predictions were generally stable when sensor data was lost, it remains to be seen whether the generalised regression networks algorithm is robust for other activities such as stair climbing.

Invasive in vivo measurement of rear-, mid- and forefoot motion during walking.

The aim of this work was to use bone anchored external markers to describe the kinematics of the tibia, fibula, talus, calcaneus, navicular, cuboid, medial cuneiform, first and fifth metatarsals during gait. Data were collected from six subjects. There was motion at all the joints studied. Movement between the talus and the tibia showed the expected predominance of sagittal plane motion, but the talocalcaneal joint displayed greater variability than expected in its motion. Movement at the talonavicular joint was greater than at the talocalcaneal joint and motion between the medial cuneiform and navicular was far greater than expected. Motion between the first metatarsal and the medial cuneiform was less than motion between the fifth metatarsal and cuboid. Overall the data demonstrated the complexity of the foot and the importance of the joints distal to the rearfoot in its overall dynamic function.

Functional units of the human foot.

Functional units in the human foot provide a meaningful basis for subdivisions of the entire foot during gait analysis as well as justified simplifications of foot models. The present study aimed to identify such functional units during walking and slow running. An invasive method based upon reflective marker arrays mounted on intracortical pins was used to register motion of seven foot bones. Six healthy subjects were assessed during walking and four of them during slow running. Angle-angle diagrams of corresponding planar bone rotations were plotted against each other and used to establish functional units. Individual functional units were accepted when the joints rotated temporally in phase and either (i) in the same direction, (ii) in the opposite direction, or (iii) when one of the two joints showed no rotation. A functional unit was generalized if all available angle-angle diagrams showed a consistent pattern. A medial array from the navicular to the first metatarsal was found to perform as a functional unit with parts rotating in the same direction and larger rotations occurring proximally. A rigid functional unit comprised the navicular and cuboid. No other functional units were identified. It was concluded that the talus, navicular, and medial cuneiform should neither be regarded as one rigid unit nor as one segment during gait analysis. The first and fifth metatarsals should also be considered separately. It was further concluded that a marker setup for gait analysis should consist of the following four segments: calcaneus, navicular-cuboid, medial cuneiform-first metatarsal, fifth metatarsal.

National profile of foot orthotic provision in the United Kingdom, part 2: podiatrist, orthotist and physiotherapy practices.

BACKGROUND: A national survey recently provided the first description of foot orthotic provision in the United Kingdom. This article aims to profile and compare the foot orthoses practice of podiatrists, orthotists and physiotherapists within the current provision. METHOD: Quantitative data were collected from podiatrists, orthotists and physiotherapists via an online questionnaire. The topics, questions and answers were developed through a series of pilot phases. The professions were targeted through electronic and printed materials advertising the survey. Data were captured over a 10 month period in 2016. Differences between professions were investigated using Chi squared and Fischer's exact tests, and regression analysis was used to predict the likelihood of each aspect of practice in each of the three professions. RESULTS: Responses from 357 podiatrists, 93 orthotists and 49 physiotherapists were included in the analysis. The results reveal statistically significant differences in employment and clinical arrangements, the clinical populations treated, and the nature and volume of foot orthoses caseload. CONCLUSION: Podiatrists, orthotists and physiotherapists provide foot orthoses to important clinical populations in both a prevention and treatment capacity. Their working context, scope of practice and mix of clinical caseload differs significantly, although there are areas of overlap. Addressing variations in practice could align this collective workforce to national allied health policy.

In vitro study of foot kinematics using a dynamic walking cadaver model.

There is a dearth of information on navicular, cuboid, cuneiform and metatarsal kinematics during walking and our objective was to study the kinematic contributions these bones might make to foot function. A dynamic cadaver model of walking was used to apply forces to cadaver feet and mobilise them in a manner similar to in vivo. Kinematic data were recorded from 13 cadaver feet. Given limitations to the simulation, the data describe what the cadaver feet were capable of in response to the forces applied, rather than exactly how they performed in vivo. The talonavicular joint was more mobile than the calcaneocuboid joint. The range of motion between cuneiforms and navicular was similar to that between talus and navicular. Metatarsals four and five were more mobile relative to the cuboid than metatarsals one, two and three relative to the cuneiforms. This work has confirmed the complexity of rear, mid and forefoot kinematics. The data demonstrate the potential for often-ignored foot joints to contribute significantly to the overall kinematic function of the foot. Previous emphasis on the ankle and sub talar joints as the principal articulating components of the foot has neglected more distal articulations. The results also demonstrate the extent to which the rigid segment assumptions of previous foot kinematics research have over simplified the foot.

Intrinsic foot kinematics measured in vivo during the stance phase of slow running.

An accurate kinematic description of the intrinsic articulations of the foot during running has not previously been presented, primarily due to methodological limitations. An invasive method based upon reflective marker arrays mounted on intracortical pins drilled into the bones was used in this study. Four male volunteers participated as subjects. Pins (1.6mm diameter) were inserted under local anaesthetic in the tibia, fibula, calcaneus, talus, navicular, cuboid, medial cuneiform and metatarsals I and V. A 10 camera motion analysis system was used for kinematic data capture and the ground reaction force was simultaneously measured. Segment motion relative to adjacent proximal segments was determined using helical axes projected into the coordinate system of the proximal segment. Coefficients of multiple correlation calculated to determine the strength of association between running style with and without the pins inserted indicated that the subjects had little restriction due to the inserted pins. Individual and mean results were presented for rotations defined in the planes of the proximal segment's coordinate system and showed frontal plane rotation of the talocrural joint (12.2+/-7.1 degrees ), which exceeded that of the subtalar joint (8.9+/-3.2 degrees ). Considerable mobility of the talonavicular joint was found (6.5+/-2.9 degrees , 13.5+/-4.1 degrees and 8.7+/-1.4 degrees in the sagittal, frontal and transverse planes, respectively). Furthermore, little, but non-negligible motion between the fibula and tibia was found (3.3+/-2.4 degrees in the sagittal plane). The presented data are of interest as input for future biomechanical modelling and clinical decision making in particular, concerning joint fusion.

Foot kinematics during walking measured using bone and surface mounted markers.

The aim was to compare kinematic data from an experimental foot model comprising four segments ((i) heel, (ii) navicular/cuboid (iii) medial forefoot, (iv) lateral forefoot), to the kinematics of the individual bones comprising each segment. The foot model was represented using two different marker attachment protocols: (a) markers attached directly to the skin; (b) markers attached to rigid plates mounted on the skin. Bone data were collected for the tibia, talus, calcaneus, navicular, cuboid, medial cuneiform and first and fifth metatarsals (n=6). Based on the mean differences between the three data sets during stance, the differences between any two of the three kinematic protocols (i.e. bone vs skin, bone vs plate, skin vs plate) were >3 degrees in only 35% of the data and >5 degrees in only 3.5% of the data. However, the maximum difference between any two of the three protocols during stance was >3 degrees in 100% of the data, >5 degrees in 73% of the data and >8 degrees in 23% of the data. Differences were greatest for motion of the combined navicular/cuboid relative to the calcaneus and the medial forefoot segment relative to the navicular/cuboid. The differences between the data from the skin and plate protocols were consistently smaller than differences between either protocol and the kinematic data for each bone comprising the segment. The pattern of differences between skin and plate protocols and the actual bone motion showed no systematic pattern. It is unlikely that one rigid body foot model and marker attachment approach is always preferable over another.

National profile of foot orthotic provision in the United Kingdom, part 1: practitioners and scope of practice.

BACKGROUND: Foot orthoses have been advocated in the management of a wide range of clinical foot and lower limb problems and are within the scope of podiatry, orthotic and physiotherapy practice. Previous reports into the provision of orthoses have consistently identified significant issues with services and devices, but data were never specific to foot orthoses. The aim of this first of a series of papers was to report the first ever national multi professional profile of foot orthosis provision in the United Kingdom. METHODS: Quantitative and qualitative data were collected from podiatrists, orthotists and physiotherapists via an online questionnaire. The topics, questions and answers were developed through a series of pilot phases. The professions were targeted through electronic and printed materials. Data were captured over a 10 month period in 2016. RESULTS: A total of 499 responses were included in analysis, including 357 podiatrists, 93 orthotists and 49 physiotherapists. The results reveal wide ranging practices across podiatrists, orthotists and physiotherapists, provision of orthoses through different health care departments (uni and multidisciplinary), for different health conditions (acute and chronic), and involving different types of orthoses (prefabricated and customised). CONCLUSION: Foot orthoses in the United Kingdom are provided in areas of well recognised health and rehabilitation priorities. A wide range of orthotic devices and practices are employed and different professions provide foot orthoses in different ways.

Patient perceptions of stock footwear design features.

Patients with diseases which impact on foot health, for example diabetes and rheumatoid arthritis, are known to have some benefit from prescribed stock footwear with regards to clinical outcomes. Achieving this is not just about getting the footwear designed and fitted to meet the clinical needs, but it also requires that the patient wears the shoes. This means meeting the non-clinical needs or criteria of patients. The aim of this study was to compare perceptions of the same footwear between patients with diabetes and patients with rheumatoid arthritis (RA) with regard to specific design features. Fifty-four patients with RA and 40 patients with diabetes who required prescription footwear were asked to identify issues of importance, and to assess the features of five different pairs of stock footwear using a Likert scale scoring form. There was a difference between the RA and the diabetes groups with regards their overall requirements from the footwear with comfort being a priority in RA and style a priority for diabetes. Both groups rated the same footwear as overall best from the selection, but the scores suggest that there were features with the 'best' shoe which were not acceptable suggesting that even the 'best' shoe was a compromise This possibly indicates that existing footwear ranges do not meet all the patients' requirements. Patients have different perceptions with regard to what is important to them in terms of footwear with regards to the specific features of the footwear and one of the influences appears to be the underlying systemic disease. Patient-based criteria may be an important consideration in the design of the footwear.

A device for characterising the mechanical properties of the plantar soft tissue of the foot.

The plantar soft tissue is a highly functional viscoelastic structure involved in transferring load to the human body during walking. A Soft Tissue Response Imaging Device was developed to apply a vertical compression to the plantar soft tissue whilst measuring the mechanical response via a combined load cell and ultrasound imaging arrangement. Accuracy of motion compared to input profiles; validation of the response measured for standard materials in compression; variability of force and displacement measures for consecutive compressive cycles; and implementation in vivo with five healthy participants. Static displacement displayed average error of 0.04 mm (range of 15 mm), and static load displayed average error of 0.15 N (range of 250 N). Validation tests showed acceptable agreement compared to a Houndsfield tensometer for both displacement (CMC > 0.99 RMSE > 0.18 mm) and load (CMC > 0.95 RMSE < 4.86 N). Device motion was highly repeatable for bench-top tests (ICC = 0.99) and participant trials (CMC = 1.00). Soft tissue response was found repeatable for intra (CMC > 0.98) and inter trials (CMC > 0.70). The device has been shown to be capable of implementing complex loading patterns similar to gait, and of capturing the compressive response of the plantar soft tissue for a range of loading conditions in vivo.

The relationship between transverse plane leg rotation and transverse plane motion at the knee and hip during normal walking.

The purpose of this study was to test the clinical hypothesis that the magnitude and temporal characteristics of rearfoot complex motion are closely correlated with those of the transverse plane motion at the knee and hip. Twenty subjects underwent kinematic assessment during walking at 108 steps/minute. The transverse plane rotation of the leg relative to the foot was used to indicate rearfoot complex pronation and supination. Taking into account errors inherent in kinematic assessment involving skin mounted markers, it is unlikely that a correlation exists between the range of internal leg rotation during the contact phase and the total range of transverse plane leg rotation during gait and the corresponding values for the transverse plane motion at the knee and hip. Correlation tests were performed to assess the temporal characteristics of the motions at the joints that showed that there was no correlation between the transverse plane motion in the rearfoot complex, knee and hip. Thus the hypothesis that the magnitude and temporal characteristics of rearfoot complex motion are closely correlated with the transverse plane motion at the knee and hip was rejected.

Effect of foot orthoses on the kinematics and kinetics of normal walking gait.

Despite their wide clinical application and success, our understanding of the biomechanical effects of foot orthoses is relatively limited. The aim of this study was to assess the effect of medially wedged and laterally wedged foot orthoses on the kinematics and joint moments of the rearfoot complex, knee, hip and pelvis and the ground reaction forces. The principal effect of the foot orthoses was on the rearfoot complex, where significant changes in joint rotations and moments were observed. Medially wedged orthoses decreased rearfoot pronation and increased the laterally directed ground reaction force during the contact phase, suggesting reduced shock attenuation. The laterally wedged orthoses increased rearfoot pronation and decreased the laterally directed ground reaction force during the contact phase, suggesting increased shock attenuation. The effects of the orthoses on knee, hip and pelvis kinematics were generally minimal. In view of the minimal effect the orthoses had on joints proximal to the foot, it is suggested that the orthoses may have additional effects on the passive and active soft tissues of the lower limb and it is these changes that result in the documented clinical success.

Effect of errors in the identification of anatomical landmarks on the accuracy of Q angle values.

OBJECTIVE: To determine the effect of error in the location of the anterior superior iliac spine, and the centres of the patella and tibial tuberosity, on the measured value of the quadriceps angle. BACKGROUND: The quadriceps angle is said to be relevant in the etiology and management of patello-femoral pain. However, the issues around measurement accuracy have not been reported. METHODS: Errors between 1 and 5 mm were introduced to the medial/lateral and vertical co-ordinate data describing the position of the anterior superior iliac spine, the centre of the patella and the centre of the tibial tuberosity, and the effect on the quadriceps angle determined. RESULTS: Errors between 1 and 5 mm in the medial/lateral location of the centre of the patella produced changes in the quadriceps angle between 1.13 degrees and 5.53 degrees. Errors between 1 and 5 mm in the medial/lateral location of the tibial tuberosity produced changes in the quadriceps angle between 1.02 degrees and 5.18 degrees. CONCLUSIONS: The quadriceps angle is highly sensitive to error in the definition of the centre of the patella and tibial tuberosity. As an approximation, these centres need to be defined with an accuracy of less than 2 mm if the error in the quadriceps angle is to remain below 5 degrees. RELEVANCE: Until a clinical technique for measuring the quadriceps angle with a high level of accuracy is developed, the clinical use of the quadriceps angle is questionable.

Effect of foot orthoses on rearfoot complex kinematics during walking gait.

The aim of this study was to quantify the effect of anti-pronatory and anti-supinatory foot orthoses on the angular displacement, velocity and accelerations of the rearfoot complex during gait. The transverse plane motion of the leg relative to the foot was used to indicate rearfoot complex pronation and supination. Three dimensional gait analysis on 12 subjects was used to derive the changes in the rearfoot kinematics due to the orthoses. The anti-pronatory orthoses decreased the range of pronation during the contact phase (p=0.0002) and the total range of rearfoot complex motion (p=0.000002), whereas anti-supinatory orthoses increased the range of pronation during the contact phase (p=0.00006) and the total range of rearfoot motion (p=0.049). Anti-pronatory orthoses also decreased the initial peak in pronation velocity during the contact phase of gait (p=0.006). Neither orthosis had a statistically significant effect on rearfoot complex acceleration.

Shank rotation: A measure of rearfoot motion during normal walking.

Motion of the shank in the transverse plane is coupled with pronation and supination of the rearfoot, and so its motion relative to the foot can be used as an indicator of the pattern of motion in the rearfoot. Compared to the more commonly used assessment of motion in the frontal plane between the heel and the shank, motion of the shank in the transverse plane relative to the foot provides a more complete measure of the pattern of motion of the rearfoot because it reflects the motion in all three joints of the rearfoot (the ankle, subtalar joint and mid-tarsal joint) not solely the ankle and subtalar components. This work aimed to provide normative data for this alternative measure of rearfoot function. Data on angular displacement, angular velocity and angular acceleration were derived from motion-analysis conducted on 25 subjects. The results suggest a difference between the pattern of angular displacement indicated when motion of the shank relative to the foot is examined and the pattern of angular displacement indicated when motion in the frontal plane between the shank and heel is examined. Specifically, the former suggests that resupination of the rearfoot after rearfoot pronation during the initial period of gait, starts at the beginning of mid-stance, while the latter suggests resupination beginning in late mid-stance. Where comparisons were possible, data on the velocity and acceleration appeared reasonable and provide further parameters with which to investigate the role of motion in the rearfoot in the development of pathologic conditions and the effects of intervention on motion in the rearfoot.

Scientific approach to the axis of rotation at the midtarsal joint.

Current biomechanical models of the midtarsal joint describe it as having two axes of rotation, the oblique and the longitudinal. The considerable freedom of movement available at the midtarsal joint means that kinematic assessment of its function and determination of its axis of rotation must be conducted under conditions that enable the joint to function as normally as possible. The assessments on which the concepts of the longitudinal and oblique axes are based do not meet this criterion. Understanding of the motions at the midtarsal joint will improve as techniques of kinematic assessment improve. Future descriptions of the midtarsal joint should adopt the standard terms applied to the other joints in the lower limb, which will facilitate the study of the midtarsal joint in relation to the function of the rest of the lower limb.