Vibration perception among children and adolescents with Charcot-Marie-tooth disease and implications for foot posture.

BACKGROUND: Alterations in vibration perception among children and adolescents with Charcot-Marie-Tooth disease might explain observed changes in foot posture. Therefore, this cross-sectional study compared the vibration perception of the lower limbs in youths with and without Charcot-Marie-Tooth disease and verified the cut-off value of the distal vibration perception for the Charcot-Marie-Tooth group. In addition, associations between dynamic plantar pressure, vibration perception and isometric muscle strength were investigated. METHODS: Participants aged 9-18 (Charcot-Marie-Tooth group n = 32; Typical group n = 32) had vibration perception measured by a 128-Hz graduated tuning fork. The static and dynamic foot posture were evaluated by the Foot Posture Index and pressure distribution measuring system, respectively. For the Charcot-Marie-Tooth group, a hand-held dynamometer evaluated the isometric muscle strength of the lower limbs. FINDINGS: Children with Charcot-Marie-Tooth disease presented impaired vibration perception at the distal phalanx of the hallux and head of the first metatarsal compared to their typically developing peers, while adolescents with Charcot-Marie-Tooth disease showed impairment in all the tested regions compared to their typically developing peers. The cut-off value for vibration perception for participants with Charcot-Marie-Tooth disease was 5.7, considering the original grade of the tuning-fork 128 Hz. Among the associations established for the Charcot-Marie-Tooth group, a greater vibration perception at the distal phalanx of the hallux was associated with a longer rearfoot contact time (ß = 31.02, p = 0.04). INTERPRETATION: These new findings may guide the clinical evaluation and rehabilitation treatment for children and adolescents with Charcot-Marie-Tooth disease.

Development of a customized booklet of foot-ankle exercises for people with diabetes mellitus as a management and prevention tool for musculoskeletal complications: A customized booklet of foot-ankle exercises for people with diabetes.

BACKGROUND: Diabetes mellitus (DM) and diabetic peripheral neuropathy (DPN) compromises the structures of the musculoskeletal system, especially in the foot-ankle complex. Foot-related exercises can be a promising tool to be incorporated in health care programs to manage and prevent musculoskeletal complications resulting from DM and DPN progression. OBJECTIVE: To present the development, validation, and usability evaluation of a booklet that directs training and personalizes the progression of a home-based program of foot-ankle exercises. METHODS: The booklet containing a foot-ankle exercise program developed in a previous clinical trial was validated using the Delphi technique, with a multi-professional jury of experts who assessed the content of the material, language, individual education, exercise execution, exercise quality, and material implementation. The validated version was evaluated through telephone interview by a convenience sample of 10 individuals with DPN regarding its relevance, health education, comprehension, and usability. RESULTS: The validation process with experts was performed in two rounds achieving 100% agreement in the second round. During the usability evaluation process the main complaint of users was that performing all the exercises was very tiring and took too much time out of their daily routine. Thus, the number of repetitions for each exercise was changed from 30 to 12. CONCLUSION: The booklet is a material for prevention and management of the impacts of DM and DPN progression by improving the musculoskeletal function of the foot-ankle. This material provides an exercise regime with a personalized progression based on the perceived effort of the users.

Dynamic plantar pressure patterns in children and adolescents with Charcot-Marie-Tooth disease.

BACKGROUND: The dynamic plantar pressure patterns of children and adolescents with Charcot-Marie-Tooth (CMT) disease and its relationship to musculoskeletal alterations may help to understand the natural history of the disease and improve therapeutic interventions. RESEARCH QUESTION: The study compared dynamic plantar pressure patterns in children and adolescents with and without CMT. It also tested the associations between isometric muscle strength (IMS), passive range of motion (ROM), foot posture and dynamic plantar pressure patterns in CMT. METHODS: This cross-sectional study compared children and adolescents (aged 8-18 years) with CMT (n = 40) with a typical group (n = 40). The plantar pressure distribution during gait was recorded, and the contact area (CA), peak pressure (PP), contact time (CT) and pressure-time integral (PTI) in five foot regions (rearfoot, midfoot lateral, midfoot medial, lateral forefoot and medial forefoot) were analysed. The IMS of the dorsiflexors and plantar flexors, passive ROM, and foot posture were also recorded. RESULTS: PP (medial midfoot and medial forefoot) and PTI (rearfoot, lateral midfoot and medial forefoot) were higher in children with CMT compared with the typical group. The adolescents with CMT presented a less CA (whole foot) and a higher CT (medial midfoot) when compared with typical group. For CMT, in the medial midfoot, plantar flexor IMS associated with PP (ß=-11.54, p = 0.01) and PTI (ß=-3.38, p = 0.04); supinated foot posture associated with PP (ß = 33.89, p = 0.03) and PTI (ß = 12.01, p = 0.03). SIGNIFICANCE: Children with CMT showed clear changes in most of the dynamic plantar pressure variables, while adolescents with CMT showed changes mostly in CA and CT. This information together with the associations established between supinated foot, dorsiflexion ROM and plantar flexions IMS can be useful for guiding rehabilitation professionals in their therapies.

Clustering classification of diabetic walking abnormalities: a new approach taking into account intralimb coordination patterns.

BACKGROUND: It is well recognized that diabetes and peripheral neuropathy have a detrimental effect on gait. However, there are large variations in the results of studies addressing this aspect due to the heterogeneity of diabetic population in relation to presence and severity of diabetes complications. The aim of this study is to adopt an unsupervised classification technique to better elucidate the gait changes throughout the entire spectrum of diabetes and neuropathy. METHODS: Sixty subjects were assessed and classified into four groups using a fuzzy logic model: 13 controls (55 ± 7years), 18 diabetics subjects without neuropathy (59 ± 6 years, 11 ± 7 diabetes years), 7 with mild neuropathy (56 ± 4years, 19 ± 7 diabetes years), and 22 with moderate to severe neuropathy (57 ± 5 years, 14 ± 8 diabetes years). Data were gathered by six infrared cameras at 100 Hz regarding lower limb joint kinematics (angles and angular velocities) and the relative phase for the hip-ankle, hip-knee, and knee-ankle were calculated. The K-means clustering algorithm was adopted to classify subjects considering the whole kinematics time series. A one-way ANOVA test was used to compare both clinical and kinematics parameters across clusters. RESULTS: Only the classification based on the intralimb coordination variables succeeded in defining 5 well separated clusters with the following clinical characteristics: controls were grouped mainly in Cluster 2, diabetics in Cluster 4, and neuropathic subjects in Cluster 5 (which included various degrees of severity). Hip-ankle coordination in Clusters 4 and 5 were significantly different (p < 0.05) with respect to Cluster 2, mainly in the stance phase. During the swing phase, differences were observed in the ankle-knee coordination (p < 0.05) across clusters. CONCLUSION: Classification based on intralimb coordination patterns succeeded in efficiently categorize gait alterations in diabetic subjects. It can be speculated that variables extracted from sagittal plane kinematics might be adopted as a support to clinical decision making in diabetes.

Rehabilitation technology for self-care: Customised foot and ankle exercise software for people with diabetes.

AIMS: To develop and validate the content of a free web-based software (desktop and mobile applications) for the self-management of and customised foot-ankle exercises for people with diabetes and diabetic neuropathy. METHODS: The development of the programme was based on gamification principles and addressed three main areas: foot care recommendations; self-assessment of feet according to the main complications of diabetic neuropathy; and customised foot-ankle exercises to strengthen muscles, increase the range of motion and improve functionality. The content was validated using the Delphi methodology and a quantitative approach in two rounds with diabetes specialists (n = 9) and users with diabetes (n = 20). A 70% approval rate was considered sufficient in the second round for final validation purposes. The data analysis was conducted using descriptive statistics, absolute and relative frequencies and the content-validity index (CVI). RESULTS: Among specialists, the CVI was 0.812 after the first round, and final approval was 100% after the second round. Among users, the CVI was 0.902 in the first round, and the final approval was 97%. CONCLUSION: This free access web software was developed based on the high agreement rating between specialists and users and has the potential to prevent complications arising from diabetic polyneuropathy. It allows for self-monitoring and promotes personalised exercises, following a preventive model that can be applied in primary and secondary care services as a complementary treatment for chronic complications. However, further steps to validate the software in a larger population are recommended.

Ulcer-risk classification and plantar pressure distribution in patients with diabetic polyneuropathy: exploring the factors that can lead to foot ulceration.

Plantar pressure is critical in the onset of neuropathic foot ulcers. However, risk classifications do not consider it as a stratification parameter. Whether plantar pressure distribution affects ulcer-risk was investigated. Patients from a research study (n. 134) and from a clinical environment (n. 83) were classified into ulcer-risk groups according to the International Working Group on the Diabetic Foot guidelines. Pressure distribution was acquired during gait (Pedar-X System), and assessed for hindfoot, midfoot, forefoot and toes (1way- and 2way-ANOVAs, p < 0.05). Pressure distribution changed with polyneuropathy even in the low-risk groups: median p = 0.048 (0.001-0.223). Risk classification correlated poorly with pressure distribution: median p = 0.686 (0.374-0.828). BMI, age and walking speed influenced most parameters and rendered the studies almost impossible to compare (2-way ANOVA factor A > 0.05). Pressure-time integral, the only comparable parameter between the two studies, may increase the predictive capacity of ulcer-risk stratification models.

Protocol for evaluating the effects of a foot-ankle therapeutic exercise program on daily activity, foot-ankle functionality, and biomechanics in people with diabetic polyneuropathy: a randomized controlled trial.

BACKGROUND: Diabetic polyneuropathy (DPN) negatively affects foot and ankle function (strength and flexibility), which itself affects the daily physical activity and quality of life of patients. A physical therapy protocol aiming to strengthen the intrinsic and extrinsic foot muscles and increase flexibility may be a promising approach to improve lower-extremity function, prevent further complications, and improve autonomy for daily living activities in these patients. Thus, the inclusion of a specific foot-related exercises focused on the main musculoskeletal impairments may have additional effects to the conventional interventions in the diabetic foot. METHODS/DESIGN: A prospective, parallel-group, outcome-assessor blinded, randomized controlled trial (RCT) will be conducted in 77 patients with DPN who will be randomly allocated to usual care (control arm) or usual care with supervised foot-ankle exercises aiming to increase strengh and flexibility twice a week for 12 weeks and remotely supervised foot-ankle exercises for a year through a web software. Patients will be evaluated 5 times in a 1 year period regarding daily physical activity level, self-selected and fast gait speeds (primary outcomes), foot ulcer incidence, ulcer risk classification, neuropathy testing, passive ankle range of motion, quality of life, foot health and functionality, foot muscle strength, plantar pressure, and foot-ankle kinematics and kinetics during gait. DISCUSSION: This study aims to assess the effect of a foot-ankle strength and flexibility program on a wide range of musculoskeletal, activity-related, biomechanical, and clinical outcomes in DPN patients. We intend to demonstrate evidence that the year-long training program is effective in increasing gait speed and daily physical activity level and in improving quality of life; foot strength, functionality, and mobility; and biomechanics while walking. The results will be published as soon as they are available. TRIAL REGISTRATION: This study has been registered at ClinicalTrials.gov as NCT02790931 (June 6, 2016) under the name "Effects of foot muscle strengthening in daily activity in diabetic neuropathic patients".

Independência funcional de crianças de um a quatro anos com mielomeningocele / Independencia funcional de niños de un a cuatro años con mielomeningocele / Functional independence of one- to four-year-old children with myelomeningocele

RESUMO A mielomeningocele é causada por defeito no fechamento do tubo neural. A doença representa a segunda causa de deficiência crônica no aparelho locomotor em crianças. A independência funcional depende do nível da lesão medular e sua avaliação é importante para a determinação de abordagens terapêuticas adequadas. O objetivo foi descrever a independência funcional e o nível de lesão de 15 crianças de seis meses a quatro anos com lesão medular completa causada por mielomeningocele. Foi realizado um estudo observacional do tipo transversal nas Universidades Ibirapuera e Santa Cecília. O Inventário de Avaliação Pediátrica de Incapacidade (Pediatric Evaluation of Disability Inventory - PEDI) foi aplicado com os pais, para avaliação da independência funcional nas atividades de vida diária das crianças. A escala de Padrões Internacionais para Classificação Neurológica de Lesão da Medula Espinhal da Associação Americana de Lesão Medular (International Standards for Neurological Classification of Spinal Cord Injury of the American Spinal Injury Association) foi utilizada para determinar o nível motor e sensitivo da lesão. Foram avaliados seis meninos e nove meninas (27,0±11,8 meses de idade). Três crianças apresentaram lesão torácica, nove apresentaram lesão lombar alta, duas apresentaram lesão lombar baixa e uma apresentou lesão sacral. As pontuações na PEDI variaram de 15 a 60% no domínio autocuidado, de 10 a 15% no domínio mobilidade e de 19 a 58% no domínio função social. Houve grande variabilidade no desempenho funcional de crianças com mielomeningocele, detectada pelos domínios autocuidado e função social da PEDI. As crianças apresentaram grande prejuízo no domínio mobilidade.

RESUMEN El mielomeningocele es causado por defecto en el cierre del tubo neural. La enfermedad representa la segunda causa de deficiencia crónica en el aparato locomotor en niños. La independencia funcional depende del nivel de la lesión medular y su evaluación es importante para determinar enfoques terapéuticos adecuados. El objetivo fue describir la independencia funcional y el nivel de lesión de 15 niños de seis meses a cuatro años con lesión medular completa causada por mielomeningocele. Se realizó un estudio observacional del tipo transversal en las Universidades Ibirapuera y Santa Cecilia. Se aplicó el Inventario de Evaluación Pediátrica de Discapacidad (Pediatric Evaluation of Disability Inventory, PEDI) con los padres para evaluar la independencia funcional en las actividades de vida diaria de los niños. La escala de Estándares Internacionales para la Clasificación Neurológica de la Lesión Medular de la Asociación Americana de la Lesión Medular (International Standards for Neurological Classification of Spinal Cord Injury of the American Spinal Injury Association) fue utilizada para determinar el nivel motor y sensitivo de la lesión. Se evaluaron seis niños y nueve niñas (27,0 ± 11,8 meses de edad). Tres niños presentaron lesión torácica, nueve presentaron lesión lumbar alta, dos presentaron lesión lumbar baja y una presentó lesión en el sacro. Las puntuaciones en la PEDI variaron del 15 al 60% en el dominio autocuidado, del 10 al 15% en el ámbito de la movilidad y del 19 al 58% en el ámbito de la función social. Hubo gran variabilidad en el desempeño funcional de los niños con mielomeningocele, detectada por los campos autocuidado y función social de la PEDI. Los niños presentaron gran daño en el dominio de la movilidad.

ABSTRACT Myelomeningocele is caused by neural tube closure defects and represents the second cause of locomotion disability in children. Functional independence depends on level of spine injury and assessment is important to determine proper therapeutic approaches. We aimed to describe functional Independence and level of injury in 15 children, aged one to four years and with complete spinal cord injury caused by myelomeningocele. This is an observational transversal study developed in the Ibirapuera University and Santa Cecília University. The Pediatric Evaluation of Disability Inventory (PEDI) was used to ask parents about the functional independence of children in daily life activities. The International Standards for Neurological Classification of Spinal Cord Injury of the American Spinal Injury Association was used to determine the motor and sensory levels. Nine girls and six boys were assessed (27.0 ±11.8 months of age). Three children showed thoracic level, nine showed high lumbar level, two were classified as low lumbar, and one as sacral level. PEDI scores varied from 15 to 60% on the self-care area, from 10 to 15% on mobility, and from 19 to 58% on social function. High variability was observed on the functional independence of children with myelomeningocele, detected by self-care and social function areas of PEDI. Mobility was the most affected domain.

Cross-cultural adaptation and measurement properties of the Brazilian Version of the Michigan Neuropathy Screening Instrument.

BACKGROUND: The Michigan Neuropathy Screening Instrument is an easy-to-use questionnaire aimed at screening and detecting diabetic polyneuropathy. OBJECTIVE: To translate and cross-culturally adapt the MNSI to Brazilian Portuguese and evaluate its measurement properties. METHODS: Two bilingual translators translated from English into Brazilian Portuguese and made a synthetic version. The synthetic version was back translated into English. A committee of specialists and the translator checked the cultural adaptations and developed a pre-final questionnaire in Brazilian Portuguese (prefinal version). In pretesting, the prefinal version was applied to a sample of 34 subjects in which each subject was interviewed to determine whether they understood each item. For the later assessment of measurement properties, 84 subjects were assessed. RESULTS: A final Brazilian Portuguese version of the instrument was produced after obtaining 80% agreement (SEM<0.01%) among diabetic patients and specialists. We obtained excellent intra-rater reliability (ICC3,1=0.90), inter-rater reliability (ICC2,1=0.90) and within-subject reliability ICC3,1=0.80, excellent internal consistency (Cronbach's alpha>0.92), reasonable construct validity for the association between the MNSI and Neuropathy Symptom Score (r=0.46, p<0.05) and excellent association between the MNSI and Neuropathy Disability Score (r=0.79, p<0.05). We did not detect floor and ceiling effects (<9.5% of patients with maximum scores). CONCLUSIONS: The Brazilian Portuguese version of the MNSI is suitable for application in the Brazilian diabetic population and is a reliable tool for the screening and detection of DPN. The MNSI can be used both in clinical practice and also for research purposes.

The effect of peripheral neuropathy on lower limb muscle strength in diabetic individuals.

BACKGROUND: Skeletal muscle strength is poorly described and understood in diabetic participants with diabetic peripheral neuropathy. This study aimed to investigate the extensor and flexor torque of the knee and ankle during concentric, eccentric, and isometric contractions in men with diabetes mellitus type 2 with and without diabetic peripheral neuropathy. METHODS: Three groups of adult men (n=92), similar in age, body mass index, and testosterone levels, were analyzed: 33 non-diabetic controls, 31 with type 2 diabetes mellitus, and 28 with diabetic peripheral neuropathy. The peak torques in the concentric, eccentric, and isometric contractions were evaluated using an isokinetic dynamometer during knee and ankle flexion and extension. FINDINGS: Individuals with diabetes and diabetic peripheral neuropathy presented similar low concentric and isometric knee and ankle torques that were also lower than the controls. However, the eccentric torque was similar among the groups, the contractions, and the joints. INTERPRETATION: Regardless of the presence of peripheral neuropathy, differences in skeletal muscle function were found. The muscle involvement does not follow the same pattern of sensorial losses, since there are no distal-to-proximal impairments. Both knee and ankle were affected, but the effect sizes of the concentric and isometric torques were found to be greater in the participants' knees than in their ankles. The eccentric function did not reveal differences between the healthy control group and the two diabetic groups, raising questions about the involvement of the passive muscle components.

Intralimb Coordination Patterns in Absent, Mild, and Severe Stages of Diabetic Neuropathy: Looking Beyond Kinematic Analysis of Gait Cycle.

AIM: Diabetes Mellitus progressively leads to impairments in stability and joint motion and might affect coordination patterns, mainly due to neuropathy. This study aims to describe changes in intralimb joint coordination in healthy individuals and patients with absent, mild and, severe stages of neuropathy. METHODS: Forty-seven diabetic patients were classified into three groups of neuropathic severity by a fuzzy model: 18 without neuropathy (DIAB), 7 with mild neuropathy (MILD), and 22 with moderate to severe neuropathy (SVRE). Thirteen healthy subjects were included as controls (CTRL). Continuous relative phase (CRP) was calculated at each instant of the gait cycle for each pair of lower limb joints. Analysis of Variance compared each frame of the CRP time series and its standard deviation among groups (α = 5%). RESULTS: For the ankle-hip CRP, the SVRE group presented increased variability at the propulsion phase and a distinct pattern at the propulsion and initial swing phases compared to the DIAB and CTRL groups. For the ankle-knee CRP, the 3 diabetic groups presented more anti-phase ratios than the CTRL group at the midstance, propulsion, and terminal swing phases, with decreased variability at the early stance phase. For the knee-hip CRP, the MILD group showed more in-phase ratio at the early stance and terminal swing phases and lower variability compared to all other groups. All diabetic groups were more in-phase at early the midstance phase (with lower variability) than the control group. CONCLUSION: The low variability and coordination differences of the MILD group showed that gait coordination might be altered not only when frank evidence of neuropathy is present, but also when neuropathy is still incipient. The ankle-knee CRP at the initial swing phase showed distinct patterns for groups from all degrees of neuropathic severity and CTRLs. The ankle-hip CRP pattern distinguished the SVRE patients from other diabetic groups, particularly in the transitional phase from stance to swing.

From treatment to preventive actions: improving function in patients with diabetic polyneuropathy.

Diabetic polyneuropathy is an insidious and long-term complication of this disease. Synergistic treatments and preventive actions are crucial because there are no clear boundaries for determining when health professionals should intervene or what intervention would best avoid the consequences of neuropathy. Until now, most therapies to any diabetic individual were applied only after the patient's limb was ulcerated or amputated. The loss of muscle and joint functions is recognized as the main cause of plantar overloading. However, if foot and ankle exercises are performed following the early diagnosis of diabetes, they can enable the patient to maintain sufficient residual function to interact with the environment. This article summarizes the current knowledge about the musculoskeletal deficits and biomechanical alterations caused by neuropathy. It also describes the potential benefits of foot and ankle exercises for any diabetic patient that is not undergoing the plantar ulcer healing process. We concentrate on the prevention of the long-term deficits of neuropathy. We also discuss the main strategies and protocols of therapeutic exercises for joints and muscles with deficits, which are applicable to all diabetic patients with mild to moderate neuropathy. We describe further efforts in exploiting the applicability of assistive technologies to improve the adherence to an exercise program. Following the contemporary trends towards self-monitoring and self-care, we developed a software to monitor and promote personalized exercises with the aim of improving autonomous performance in daily living tasks. Initiatives to prevent the complications of functional diabetes are highly recommended before it is too late for the patient and there is no longer an opportunity to reverse the tragic consequences of neuropathy progression.

An 'Importance' Map of Signs and Symptoms to Classify Diabetic Polyneuropathy: An Exploratory Data Analysis.

AIMS/HYPOTHESIS: Early diagnosis of diabetic polyneuropathy (DPN) is critical for a good prognosis. We aimed to identify different groups of patients, based on the various common clinical signs and symptoms of DPN, that represent a progressive worsening of the disease before the onset of plantar ulceration or amputation. We also sought to identify the most important DPN-related variables that can discriminate between groups, thus representing the most informative variables for early detection. METHODS: In 193 diabetic patients, we assessed 16 DPN-related signs, symptoms, and foot characteristics, based on the literature and the International Consensus on the Diabetic Foot. We used multiple correspondence analysis and the Kohonen algorithm to group the variables into micro and macro-classes and to identify clusters of patients that represent different DPN conditions. RESULTS: Four distinct groups were observed. One group showed no indication of DPN. The remaining groups were characterized by a progressive loss of the vibration perception, without a worsening of symptoms or tactile perception. The 2 intermediate groups presented different aspects of DPN: one showed mostly DPN symptoms and the other showed the incipient vibration impairment, callus and crack formation, and foot arch alteration. The fourth group showed more severe foot and DPN conditions, including ulceration and amputation, absence of vibration and tactile perception (irrespective of how many compromised foot areas), and worse foot deformities and callus and crack formation. CONCLUSION: Vibration perception was more informative than tactile sensitivity in discriminating early DPN onset because its impairment was evident in more groups. Symptoms and callus and cracks did not discriminate the severity status and should be interpreted in association with other clinical variables. Reconsideration of the current screening techniques is needed to clinically determine the early onset of neuropathy using tactile perception.

Alterations in the lower limb joint moments precede the peripheral neuropathy diagnosis in diabetes patients.

BACKGROUND: Changes in gait patterns in individuals with diabetes and neuropathy are still inconclusive. Our aim was to identify differences in the net intralimb moments distribution and lower limb kinematics during gait in different stage of diabetes. SUBJECTS AND METHODS: This was an observational cross-sectional study that assessed 38 adults: a control group (n=12), a group with diabetes (n=12), and a group with diabetic neuropathy (n=14). The flexor and extensor joint moment peaks and kinematics of ankle, knee, and hip angles were compared among groups (by analysis of variance). RESULTS: At initial contact, both diabetes groups present more hip flexion and smaller hip extensor moment. During late midstance, hip extension decreases, and flexion moment increases in both diabetes groups. For the same diabetes groups, during push off, the hip is more flexed, and the hip extensor moment decreases. Only for the diabetes group without neuropathy is the knee markedly more flexed, and the extensor moment is higher than in the other groups. At push off, the ankle is less extended in both diabetes groups, but the ankle extensor moment is significantly smaller only in neuropathic subjects. CONCLUSIONS: The biomechanical modifications on the gait appeared to be a continuous process that was already revealed in patients without neuropathy. The use of the hip joint as a mechanism of forward progression of the body, instead of using the ankle, was more evident and consistent for the patients with diabetic neuropathy. The knee seems to have a major role in those with diabetes without neuropathy who presented higher extensor moments to support the body during early stance.

Abnormalities of plantar pressure distribution in early, intermediate, and late stages of diabetic neuropathy.

Inconsistent findings with regard to plantar pressure while walking in the diabetic population may be due to the heterogeneity of the studied groups resulting from the classification/grouping criteria adopted. The clinical diagnosis and classification of diabetes have inherent uncertainties that compromise the definition of its onset and the differentiation of its severity stages. A fuzzy system could improve the precision of the diagnosis and classification of diabetic neuropathy because it takes those uncertainties into account and combines different assessment methods. Here, we investigated how plantar pressure abnormalities evolve throughout different severity stages of diabetic polyneuropathy (absent, n=38; mild, n=20; moderate, n=47; severe, n=24). Pressure distribution was analysed over five areas while patients walked barefoot. Patients with mild neuropathy displayed an increase in pressure-time integral at the forefoot and a lower peak pressure at the heel. The peak and pressure-time integral under the forefoot and heel were aggravated in later stages of the disease (moderate and severe) compared with early stages of the disease (absent and mild). In the severe group, lower pressures at the lateral forefoot and hallux were observed, which could be related to symptoms that develop with the aggravation of neuropathy: atrophy of the intrinsic foot muscles, reduction of distal muscle activity, and joint stiffness. Although there were clear alterations over the forefoot and in a number of plantar areas with higher pressures within each severity stage, they did not follow the aggravation evolution of neuropathy classified by the fuzzy model. Based on these results, therapeutic interventions should begin in the early stages of this disease to prevent further consequences of the disease.

Multichannel EMG-based estimation of fiber conduction velocity during isometric contraction of patients with different stages of diabetic neuropathy.

This study compares muscle fiber conduction velocities estimated using surface electromyography during isometric maximal voluntary contraction in different stages of diabetic neuropathy. Eighty-five adults were studied: 16 non-diabetic individuals and 69 diabetic patients classified into four neuropathy stages, defined by a fuzzy expert system: absent (n=26), mild (n=21), moderate (n=11) and severe (n=11). Average muscle fiber conduction velocities of gastrocnemius medialis, tibialis anterior, vastus lateralis and biceps femoris were assessed using linear array electrodes, and were compared by ANOVA. Conduction velocities were significantly decreased in the moderate neuropathy group for the vastus lateralis compared to other groups (from 18% to 21% decrease), and were also decreased in all diabetic groups for the tibialis anterior (from 15% to 20% from control group). Not only the distal anatomical localization of the muscle affects the conduction velocity, but also the proportion of muscle fiber type, where the tibialis anterior with greater type I fiber proportion is affected earlier while the vastus lateralis with greater type II fiber proportion is affected in later stages of the disease. Generally, the muscles of the lower limb have different responsiveness to the effects of diabetes mellitus and show a reduction in the conduction velocity as neuropathy progresses.

Effects of strengthening, stretching and functional training on foot function in patients with diabetic neuropathy: results of a randomized controlled trial.

BACKGROUND: Foot musculoskeletal deficits are seldom addressed by preventive medicine despite their high prevalence in patients with diabetic polyneuropathy. AIM: To investigate the effects of strengthening, stretching, and functional training on foot rollover process during gait. METHODS: A two-arm parallel-group randomized controlled trial with a blinded assessor was designed. Fifty-five patients diagnosed with diabetic polyneuropathy, 45 to 65 years-old were recruited. Exercises for foot-ankle and gait training were administered twice a week, for 12 weeks, to 26 patients assigned to the intervention group, while 29 patients assigned to control group received recommended standard medical care: pharmacological treatment for diabetes and foot care instructions. Both groups were assessed after 12 weeks, and the intervention group at follow-up (24 weeks). Primary outcomes involved foot rollover changes during gait, including peak pressure (PP). Secondary outcomes involved time-to-peak pressure (TPP) and pressure-time integral (PTI) in six foot-areas, mean center of pressure (COP) velocity, ankle kinematics and kinetics in the sagittal plane, intrinsic and extrinsic muscle function, and functional tests of foot and ankle. RESULTS: Even though the intervention group primary outcome (PP) showed a not statistically significant change under the six foot areas, intention-to-treat comparisons yielded softening of heel strike (delayed heel TPP, p=.03), better eccentric control of forefoot contact (decrease in ankle extensor moment, p<.01; increase in function of ankle dorsiflexion, p<.05), earlier lateral forefoot contact with respect to medial forefoot (TPP anticipation, p<.01), and increased participation of hallux (increased PP and PTI, p=.03) and toes (increase in PTI, medium effect size). A slower COP mean velocity (p=.05), and an increase in overall foot and ankle function (p<.05) were also observed. In most cases, the values returned to baseline after the follow-up (p<.05). CONCLUSIONS: Intervention discreetly changed foot rollover towards a more physiological process, supported by improved plantar pressure distribution and better functional condition of the foot ankle complex. Continuous monitoring of the foot status and patient education are necessary, and can contribute to preserving the integrity of foot muscles and joints impaired by polyneuropathy. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01207284, registered in 20th September 2010.

Effect of diabetic neuropathy severity classified by a fuzzy model in muscle dynamics during gait.

BACKGROUND: Electromyography (EMG) alterations during gait, supposedly caused by diabetic sensorimotor polyneuropathy, are subtle and still inconsistent, due to difficulties in defining homogeneous experimental groups with a clear definition of disease stages. Since evaluating these patients involve many uncertainties, the use of a fuzzy model could enable a better discrimination among different stages of diabetic polyneuropathy and lead to a clarification of when changes in muscle activation start occurring. The aim of this study was to investigate EMG patterns during gait in diabetic individuals with different stages of DSP severity, classified by a fuzzy system. METHODS: 147 subjects were divided into a control group (n = 30) and four diabetic groups: absent (n = 43), mild (n = 30), moderate (n = 16), and severe (n = 28) neuropathy, classified by a fuzzy model. The EMG activity of the vastus lateralis, tibialis anterior, and gastrocnemius medialis were measured during gait. Temporal and relative magnitude variables were compared among groups using ANOVA tests. RESULTS: Muscle activity changes are present even before an established neural involvement, with delay in vastus lateralis peak and lower tibialis anterior relative magnitude. These alterations suggest an impaired ankle shock absorption mechanism, with compensation at the knee. This condition seems to be more pronounced in higher degrees of neuropathy, as there is an increased vastus lateralis activity in the mild and severe neuropathy groups. Tibialis anterior onset at terminal stance was anticipated in all diabetic groups; at higher degrees of neuropathy, the gastrocnemius medialis exhibited activity reduction and peak delay. CONCLUSION: EMG alterations in the vastus lateralis and tibialis anterior occur even in the absence of diabetic neuropathy and in mild neuropathic subjects, seemingly causing changes in the shock absorption mechanisms at the heel strike. These changes increase with the onset of neural impairments, and the gastrocnemius medialis starts presenting altered activity in the later stages of the disease (moderate and severe neuropathy). The degree of severity of diabetic neuropathy must be taken into account when analyzing diabetic patients' biomechanical patterns of locomotion; we recommend the use of a fuzzy model for classification of disease stages.

Diabetic patients with and without peripheral neuropathy reveal different hip and ankle biomechanical strategies during stair descent / Pacientes diabéticos com e sem a neuropatia periférica mostram diferentes estratégias biomecânicas de quadril e tornozelo ao descer escada

BACKGROUND: The progression of diabetes and the challenge of daily tasks may result in changes in biomechanical strategies. Descending stairs is a common task that patients have to deal with, however it still has not been properly studied in this population. OBJECTIVES: We describe and compare the net joint moments and kinematics of the lower limbs in diabetic individuals with and without peripheral neuropathy and healthy controls during stair descent. METHOD: Forty-two adults were assessed: control group (13), diabetic group (14), and neuropathic diabetic group (15). The flexor and extensor net moment peaks and joint angles of the hip, knee, and ankle were described and compared in terms of effect size and ANOVAs (p<0.05). RESULTS: Both diabetic groups presented greater dorsiflexion [large effect size] and a smaller hip extensor moment [large effect size] in the weight acceptance phase. In the propulsion phase, diabetics with and without neuropathy showed a greater hip flexor moment [large effect size] and smaller ankle extension [large effect size]. CONCLUSION: Diabetic patients, even without neuropathy, revealed poor eccentric control in the weight acceptance phase, and in the propulsion phase, they showed a different hip strategy, where they chose to take the leg off the ground using more flexion torque at the hip instead of using a proper ankle extension function.

CONTEXTUALIZAÇÃO: A progressão do Diabetes Mellito e as atividades desafiadoras do dia a dia podem resultar em mudanças da estratégia biomecânica adotada. Descer escadas é uma tarefa comum do dia a dia, vivenciada pelos pacientes, mas ainda não foi satisfatoriamente estudada nessa população. OBJECTIVOS: Descrever e comparar os momentos articulares e a cinemática de membros inferiores em indivíduos diabéticos com e sem a neuropatia periférica e controles saudáveis durante o descer escadas. MÉTODO: Quarenta e dois adultos foram avaliados: grupo controle (13), grupo diabético (15) e grupo de diabéticos neuropatas (14). Os picos flexores e extensores dos momentos articulares e os ângulos articulares de quadril, joelho e tornozelo foram comparados e descritos por análise do tamanho do efeito e ANOVAs (p<0,05). RESULTADOS: Na fase de aceitação do peso, ambos os grupos diabéticos apresentaram maior ângulo de dorsiflexão de tornozelo [tamanho de efeito grande] e menor momento extensor de quadril [tamanho de efeito grande]. Na fase de propulsão, diabéticos com e sem a neuropatia apresentaram maior momento flexor de quadril [tamanho de efeito grande] e menor ângulo de extensão de tornozelo [tamanho de efeito grande]. CONCLUSÃO: Pacientes diabéticos, mesmo antes da neuropatia instalada, revelaram um pobre controle excêntrico na fase de aceitação do peso e, na fase de propulsão, esses pacientes mostraram uma estratégia diferente ao levar o membro inferior à frente a partir de um maior torque flexor de quadril ao invés de usar uma função extensora apropriada de tornozelo.

Effect of a rocker non-heeled shoe on EMG and ground reaction forces during gait without previous training.

Unstable shoes have been designed to promote "natural instability" and during walking they should simulate barefoot gait, enhancing muscle activity and, thus, attributing an advantage over regular tennis shoes. Recent studies showed that, after special training on the appropriate walking pattern, the use of the Masai Barefoot Technology (MBT) shoe increases muscle activation during walking. Our study presents a comparison of muscle activity as well as horizontal and vertical forces during gait with the MBT, a standard tennis shoe and barefoot walking of healthy individuals without previous training. These variables were compared in 25 female subjects and gait conditions were compared using ANOVA repeated measures (effect size:0.25). Walking with the MBT shoe in this non-instructed condition produced higher vertical forces (first vertical peak and weight acceptance rate) than walking with a standard shoe or walking barefoot, which suggests an increase in the loads received by the musculoskeletal system, especially at heel strike. Walking with the MBT shoe did not increase muscle activity when compared to walking with the standard shoe. The barefoot condition was more effective than the MBT shoe at enhancing muscle activation. Therefore, in healthy individuals, no advantage was found in using the MBT over a standard tennis shoe without a special training period. Further studies using the MBT without any instruction over a longer period are needed to evaluate if the higher loads observed in the present study would return to their baseline values after a period of adaptation, and if the muscle activity would increase over time.