Gait problems in diabetic neuropathic patients

Balance and gait in individuals with diabetic peripheral neuropathy

BACKGROUND

Diabetic Peripheral Neuropathy (DPN) causes various physical problems such as the increased risk of falling, loss of balance and coordination while standing or walking, susceptibility to injuries due to sensory loss.

AIMS

The aim of the study was to evaluate and compare the effects of neuropathic pain (NP) in individuals with DPN on balance and gait.

METHODS

This prospective controlled study was conducted on 42 adults aged between 40-65 years. The participants were divided into three groups; individuals with DPN and NP (DPN+NP/n = 14), individuals with DPN without NP (DPN-NP/n = 14), and the control group (n = 14), respectively. The Force Plate system and Core Balance System measured static and dynamic postural balance and stability limits. Gait and dynamic plantar pressure distribution analyses were performed with a computerized gait evaluation system.

RESULTS

The score of LANSS, and VAS during gait were higher in DPN+NP group than in DPN-NP (p < 0.05). No significant difference was observed between the groups in balance parameters (p > 0.05). The right-left heel maximum forces were lower in both groups with DPN compared to the control group (p < 0.05). In terms of spatiotemporal parameters of the gait, there was a difference between the groups only in step width and left single support line parameters (p < 0.05).

CONCLUSIONS

The results of this study indicate that the individuals with DPN have an increased step width, their left single support line was shortened, and the maximum force on the heel decreased. The NP did not cause any change in balance and gait parameters.

Intelligent Care Management for Diabetic Foot Ulcers: A Scoping Review of Computer Vision and Machine Learning Techniques and Applications

Ten percent of adults in the United States have a diagnosis of diabetes and up to a third of these individuals will develop a diabetic foot ulcer (DFU) in their lifetime. Of those who develop a DFU, a fifth will ultimately require amputation with a mortality rate of up to 70% within five years. The human suffering, economic burden, and disproportionate impact of diabetes on communities of color has led to increasing interest in the use of computer vision (CV) and machine learning (ML) techniques to aid the detection, characterization, monitoring, and even prediction of DFUs. Remote monitoring and automated classification are expected to revolutionize wound care by allowing patients to self-monitor their wound pathology, assist in the remote triaging of patients by clinicians, and allow for more immediate interventions when necessary. This scoping review provides an overview of applicable CV and ML techniques. This includes automated CV methods developed for remote assessment of wound photographs, as well as predictive ML algorithms that leverage heterogeneous data streams. We discuss the benefits of such applications and the role they may play in diabetic foot care moving forward. We highlight both the need for, and possibilities of, computational sensing systems to improve diabetic foot care and bring greater knowledge to patients in need.

"PNP slows down" - linearly-reduced whole body joint velocities and altered gait patterns in polyneuropathy

Introduction

Gait disturbances are a common consequence of polyneuropathy (PNP) and a major factor in patients' reduced quality of life. Less is known about the underlying mechanisms of PNP-related altered motor behavior and its distribution across the body. We aimed to capture whole body movements in PNP during a clinically relevant mobility test, i.e., the Timed Up and Go (TUG). We hypothesize that joint velocity profiles across the entire body would enable a deeper understanding of PNP-related movement alterations. This may yield insights into motor control mechanisms responsible for altered gait in PNP.

Methods

20 PNP patients (61 ± 14 years) and a matched healthy control group (CG, 60 ± 15 years) performed TUG at (i) preferred and (ii) fast movement speed, and (iii) while counting backward (dual-task). We recorded TUG duration (s) and extracted gait-related parameters [step time (s), step length (cm), and width (cm)] during the walking sequences of TUG and calculated center of mass (COM) velocity [represents gait speed (cm/s)] and joint velocities (cm/s) (ankles, knees, hips, shoulders, elbows, wrists) with respect to body coordinates during walking; we then derived mean joint velocities and ratios between groups.

Results

Across all TUG conditions, PNP patients moved significantly slower (TUG time, gait speed) with prolonged step time and shorter steps compared to CG. Velocity profiles depend significantly on group designation, TUG condition, and joint. Correlation analysis revealed that joint velocities and gait speed are closely interrelated in individual subjects, with a 0.87 mean velocity ratio between groups.

Discussion

We confirmed a PNP-related slowed gait pattern. Interestingly, joint velocities in the rest of the body measured in body coordinates were in a linear relationship to each other and to COM velocity in space coordinates, despite PNP. Across the whole body, PNP patients reduce, on average, their joint velocities with a factor of 0.87 compared to CG and thus maintain movement patterns in terms of velocity distributions across joints similarly to healthy individuals. This down-scaling of mean absolute joint velocities may be the main source for the altered motor behavior of PNP patients during gait and is due to the poorer quality of their somatosensory information.

Clinical Trial Registration

https://drks.de/search/de, identifier DRKS00016999.

Bioinspired preactivation reflex increases robustness of walking on rough terrain

Walking on unknown and rough terrain is challenging for (bipedal) robots, while humans naturally cope with perturbations. Therefore, human strategies serve as an excellent inspiration to improve the robustness of robotic systems. Neuromusculoskeletal (NMS) models provide the necessary interface for the validation and transfer of human control strategies. Reflexes play a crucial part during normal locomotion and especially in the face of perturbations, and provide a simple, transferable, and bio-inspired control scheme. Current reflex-based NMS models are not robust to unexpected perturbations. Therefore, in this work, we propose a bio-inspired improvement of a widely used NMS walking model. In humans, different muscles show an increase in activation in anticipation of the landing at the end of the swing phase. This preactivation is not integrated in the used reflex-based walking model. We integrate this activation by adding an additional feedback loop and show that the landing is adapted and the robustness to unexpected step-down perturbations is markedly improved (from 3 to 10 cm). Scrutinizing the effect, we find that the stabilizing effect is caused by changed knee kinematics. Preactivation, therefore, acts as an accommodation strategy to cope with unexpected step-down perturbations, not requiring any detection of the perturbation. Our results indicate that such preactivation can potentially enable a bipedal system to react adequately to upcoming unexpected perturbations and is hence an effective adaptation of reflexes to cope with rough terrain. Preactivation can be ported to robots by leveraging the reflex-control scheme and improves the robustness to step-down perturbation without the need to detect the perturbation. Alternatively, the stabilizing mechanism can also be added in an anticipatory fashion by applying an additional knee torque to the contralateral knee.

Association between P300 parameters and cognitive function in people with diabetic neuropathy

Purpose

The purpose of this study was to investigate the association between event-related potential (ERP) P300 with cognitive function in people with diabetic peripheral neuropathy (DPN).

Methods

We performed a cross-sectional analysis of 19 type 2 diabetes mellitus (T2DM) patients, aged 18 and older with DPN. The participants were assessed for neuropathy, cognitive function, & dual-task performance. DPN was examined via the administration of diabetic neuropathy symptom score (DNSS) and vibration perception threshold (VPT). Cognitive dysfunction was evaluated using Mini-mental state examination (MMSE), trail making test-B (TMT-B), and ERP P300 wave latency & amplitude. For assessing dual-task performance, the dual-task cost (DTC) was calculated using the timed-up and go (TUG) test and TUG with dual task (TUG-DT).

Results

P300 latency was linearly related to TMT-B (R = 0.31, p = 0.01) and DTC (R = 0.22, p = 0.04). A similar trend was observed in TMT-B (R = 0.13, p = 0.04) & DTC (R =0 .67, p = 0.001) with respect to P300 amplitude. MMSE did not relate with P300 latency (R = 0.14, p = 0.58) & amplitude (R = 0.63, p = .44).

Conclusion

P300 latency and amplitude are associated with cognitive function and DTC of individuals with DPN.

The influence of isometric resisted ankle strength on dynamic foot plantar pressure in diabetes and non-diabetes participants

<b>Introduction</b>: Patients with diabetes are more likely to fall due to increased plantar pressure and decreased strength in the lower extremities.<br /> <b>Objectives:</b> To determine the influence of isometric ankle strength on dynamic foot plantar pressure in diabetes and non-diabetes participants.<br /> <b>Methods: </b>Twenty diabetes patients and twenty non-diabetes participants with age 28-54 years, height 150-182 cm, weight 48-90 kg, and BMI 25-54 kg/m² participated in the study. The diabetes level was determined based on fasting plasma glucose levels. The resisted isometric muscle strength of the foot during dorsiflexion, plantar flexion, inversion, and eversion was measured using an electronic handheld dynamometer. The plantar pressure distribution during dynamic conditions was determined by using a 48.7×44.7 cm pressure platform. The outcome measures between diabetes and non-diabetes groups were statistically compared by student t-test. The correlation coefficient was determined by the Pearson correlation coefficient test. A p-value of less than 0.05 was considered significant.<br /> <b>Result: </b>The significant differences were found between diabetes and non-diabetes participants for the dorsiflexion (p=.048), plantarflexion (p=.031), inversion (p=.011), eversion (p=.024), peak pressure (p=.024), pressure per square inch (p=.012), pressure time integral (p=.014), and peak pressure gradient (p=.009). Significant relationships between resisted isometric ankle joint strength and foot plantar pressure for diabetes patients and non-diabetes participants were found.<br /> <b>Conclusion: </b>The present study’s findings reflect the higher frequency of plantar pressure distribution and higher muscle weakness in diabetes patients than in non-diabetes participants. These findings suggested that pressure data could help us to customize therapy strategies for patients with diabetes and prescribe a proper exercise intervention’s short-and long-term effects on gait biomechanics.

Impact of biomechanics on therapeutic interventions and rehabilitation for major chronic musculoskeletal conditions: A 50-year perspective

The pivotal role of biomechanics in the past 50 years in consolidating the basic knowledge that underpins prevention and rehabilitation measures has made this area a great spotlight for health practitioners. In clinical practice, biomechanics analysis of spatiotemporal, kinematic, kinetic, and electromyographic data in various chronic conditions serves to directly enhance deeper understanding of locomotion and the consequences of musculoskeletal dysfunctions in terms of motion and motor control. It also serves to propose straightforward and tailored interventions. The importance of this approach is supported by myriad biomechanical outcomes in clinical trials and by the development of new interventions clearly grounded on biomechanical principles. Over the past five decades, therapeutic interventions have been transformed from fundamentally passive in essence, such as orthoses and footwear, to emphasizing active prevention, including exercise approaches, such as bottom-up and top-down strengthening programs for runners and people with osteoarthritis. These approaches may be far more effective inreducing pain, dysfunction, and, ideally, incidence if they are based on the biomechanical status of the affected person. In this review, we demonstrate evidence of the impact of biomechanics and motion analysis as a foundation for physical therapy/rehabilitation and preventive strategies for three chronic conditions of high worldwide prevalence: diabetes and peripheral neuropathy, knee osteoarthritis, and running-related injuries. We conclude with a summary of recommendations for future studies needed to address current research gaps.

Sensory-Motor Mechanisms Increasing Falls Risk in Diabetic Peripheral Neuropathy

Diabetic peripheral neuropathy (DPN) is associated with peripheral sensory and motor nerve damage that affects up to half of diabetes patients and is an independent risk factor for falls. Clinical implications of DPN-related falls include injury, psychological distress and physical activity curtailment. This review describes how the sensory and motor deficits associated with DPN underpin biomechanical alterations to the pattern of walking (gait), which contribute to balance impairments underpinning falls. Changes to gait with diabetes occur even before the onset of measurable DPN, but changes become much more marked with DPN. Gait impairments with diabetes and DPN include alterations to walking speed, step length, step width and joint ranges of motion. These alterations also impact the rotational forces around joints known as joint moments, which are reduced as part of a natural strategy to lower the muscular demands of gait to compensate for lower strength capacities due to diabetes and DPN. Muscle weakness and atrophy are most striking in patients with DPN, but also present in non-neuropathic diabetes patients, affecting not only distal muscles of the foot and ankle, but also proximal thigh muscles. Insensate feet with DPN cause a delayed neuromuscular response immediately following foot–ground contact during gait and this is a major factor contributing to increased falls risk. Pronounced balance impairments measured in the gait laboratory are only seen in DPN patients and not non-neuropathic diabetes patients. Self-perception of unsteadiness matches gait laboratory measures and can distinguish between patients with and without DPN. Diabetic foot ulcers and their associated risk factors including insensate feet with DPN and offloading devices further increase falls risk. Falls prevention strategies based on sensory and motor mechanisms should target those most at risk of falls with DPN, with further research needed to optimise interventions.

Fit for purpose? Footwear for patients with and without diabetic peripheral neuropathy: A cross-sectional study

AIM

This paper determines whether patients with and without Diabetic Peripheral Neuropathy use suitable footwear, taking into account that these persons are subject to a significant loss of sensitivity in the feet.

METHODS

Cross-sectional observational study was conducted of 108 participants with diabetes mellitus. Inclusion criteria were at least five years' progression of diabetes, the ability to walk unaided and no distal amputation of the foot. The presence of DPN was evaluated according to the criteria of the International Working Group on the Diabetic Foot. Foot length was measured using a Brannock® device and internal shoe length was determined using a CEGI® pedometer.

RESULTS

In relation to adjustment, 21.6% of the shoes examined had no type of closure. The most common form of closure was laces, which were used in 32.4% of the shoes. 92.5% of footwear had internal seams. No significant relationship was found between the presence or otherwise of DPN and the use of appropriate shoe closure (p = 0.304), recommended heel height (p = 0.18), leather material (p = 0.77) and absence of internal seams (p = 0.759).

CONCLUSIONS

The majority of our participants living with DPN do not wear fitting shoes. Therefore, it is advisable to evaluate their use of footwear, both in primary health care and in podiatry clinics, to forestall potential complications.

Clinical 3-D Gait Assessment of Patients With Polyneuropathy Associated With Hereditary Transthyretin Amyloidosis

Hereditary amyloidosis associated with transthyretin V30M (ATTRv V30M) is a rare and inherited multisystemic disease, with a variable presentation and a challenging diagnosis, follow-up and treatment. This condition entails a definitive and progressive motor impairment that compromises walking ability from near onset. The detection of the latter is key for the disease's diagnosis. The aim of this work is to perform quantitative 3-D gait analysis in ATTRv V30M patients, at different disease stages, and explore the potential of the obtained gait information for supporting early diagnosis and/or stage distinction during follow-up. Sixty-six subjects (25 healthy controls, 14 asymptomatic ATTRv V30M carriers, and 27 symptomatic patients) were included in this case-control study. All subjects were asked to walk back and forth for 2 min, in front of a Kinect v2 camera prepared for body motion tracking. We then used our own software to extract gait-related parameters from the camera's 3-D body data. For each parameter, the main subject groups and symptomatic patient subgroups were statistically compared. Most of the explored gait parameters can potentially be used to distinguish between the considered group pairs. Despite of statistically significant differences being found, most of them were undetected to the naked eye. Our Kinect camera-based system is easy to use in clinical settings and provides quantitative gait information that can be useful for supporting clinical assessment during ATTRv V30M onset detection and follow-up, as well as developing more objective and fine-grained rating scales to further support the clinical decisions.

INFLUENCE OF DIABETIC NEUROPATHY ON GAIT COMPLEXITY

ABSTRACT Introduction: Human gait is a complex movement dependent on multilevel neural control, which allows a consistent, regular and complex periodic pattern, properties that characterize it as a nonlinear system. Sensory and motor deficits, with diminished proprioceptive responses, may reduce the adaptive capacity of the system, as demonstrated in Parkinson's, Alzheimer's and Huntington's diseases. However, little is known about the effect of peripheral diabetic neuropathy on these responses. Objectives: To analyze the influence of peripheral diabetic neuropathy on entropy in different gait environments. Methods: Ten elderly patients, with and without a diagnosis of peripheral diabetic neuropathy, walked on a treadmill (initial speed of 3 km/h, with 0.5 km/h increments every 5 minutes up to the speed of 5 km/h) to record center of mass acceleration in the vertical, mediolateral and anteroposterior components throughout the test. The sample entropy of the three vectors was calculated for each test speed. Results: The vertical component did not show any statistically significant differences. The mediolateral component showed statistically significant difference for the factors group, speed, and interaction between factors (group and speed). The anteroposterior component showed statistically significant differences for the group factor, but not for speed and interaction between factors (group and speed). Effect sizes classified as large were found in all the comparisons. Conclusions: Peripheral diabetic neuropathy produced changes in the ability to adapt to changes in the environment during gait, probably due to changes in the complexity of the multilevel neural control system, which depends on motor and sensory feedback, known to be affected by peripheral diabetic neuropathy. Level of Evidence II; Diagnostic studies - Investigating a diagnostic test.

Examination of the effects of coordination and balance problems on gait in ataxic multiple sclerosis patients

OBJECTIVE

To investigate the effects of coordination and balance problems on gait and plantar pressure distribution in multiple sclerosis patients.

METHODS

This was an observational, cross-sectional study. It was conducted at Necmettin Erbakan University between March and December 2017. Twenty-four individuals with coordination problems, 36 individuals with balance problems and 32 healthy individuals were included in the study. The EDSS, Functional Reach Test, Dynamic Gait Index, baropodometry and stabilometry evaluations were performed.

RESULTS

There were significant differences between the groups (velocity p=0.000, cadence p=0.000, step width p=0.018, step length p=0.000, foot angle p=0.000). Multiple comparisons demonstrated that the velocities and cadences of the coordination group were lower, while their step widths were found to be higher, compared to the balance group (p=0.012, p=0.004, p=0.017, respectively). In static plantar pressure distribution, lateral forefoot pressure, lateral hindfoot pressure and medial hindfoot pressure were significantly different between the groups (p=0.002, p=0.000, respectively) Multiple comparisons showed that the pressure on the lateral part of the hindfoot in the coordination group was found to be significantly higher compared to the balance group (p=0.002). According to the dynamic plantar pressure distribution, lateral forefoot, medial forefoot, lateral hindfoot and medial hindfoot pressures were significantly different between the groups (p<0.05).

CONCLUSION

Coordination and balance problems affect gait and plantar pressure distribution. The identification of these changes will help physiotherapists determine specific therapeutic targets.

Characteristics of the gait initiation phase in older adults with diabetic peripheral neuropathy compared to control older adults

BACKGROUND

Gait is deteriorated in older adults with diabetic peripheral neuropathy; however, too little is known about the gait initiation phase. We aimed to determine if gait initiation variables are more sensitive in identifying the extent to which diabetic peripheral neuropathy impacts gait.

METHODS

We examined steps, distance, speed and dynamic balance in the gait initiation phase using a validated algorithm based on wearable sensors in 38 older adults with diabetic peripheral neuropathy and 33 non-diabetic, non-neurologic, non-orthopedic control older adults (≥65 years) under single-task and dual-task gait conditions.

FINDINGS

During the single-task gait condition, the largest differences between the two groups were found in gait initiation steps and dynamic balance (66.7% more steps and 57.2% poorer balance for the diabetic group; effect size = 1.08 and 1.11, respectively; all p < 0.05), while gait speed had a medium effect (10.9% slower for the diabetic group; effect size = 0.54; p < 0.05). Although gait deteriorated for both groups during the dual-task gait condition compared to the single-task gait condition, effect sizes of the between-group differences remained similar. The differences in gait initiation steps and dynamic balance between the two groups were independent of gait speed.

INTERPRETATION

Gait initiation steps and dynamic balance may be more sensitive than gait speed for detecting gait deterioration due to diabetic peripheral neuropathy. Given the association between gait initiation and risk for fall, our findings suggest that gait initiation variables may be important outcomes for clinical management of diabetic peripheral neuropathy.

Diabetic Gait Is Not Just Slow Gait: Gait Compensations in Diabetic Neuropathy

BACKGROUND

Neuropathic complications from diabetes mellitus affect multiple nerve types and may manifest in gait. However, gait compensations are still poorly understood, as narrow analyses and lack of speed controls have contributed to conflicting or equivocal results.

PURPOSE

To evaluate gait mechanics and energetics in diabetic peripheral polyneuropathy.

METHODS

Instrumented gait analysis was performed on 14 participants with diabetic peripheral polyneuropathy and 14 matched controls, walking at 1.0 m/s. A full-body model with a multisegment foot was used to calculate inverse dynamics and analyze sagittal plane metrics and time series waveforms across stance phase.

RESULTS

Alterations included increased hip and knee flexion in early stance followed by a prolonged hip extension moment in midstance. Late stance ankle dorsiflexion and power absorption were increased, and final push-off was delayed and truncated.

CONCLUSION

A neuropathic diabetic gait shares important similarities to a mild crouch gait with weakness/dysfunction in the foot and ankle. This study highlights two main compensation mechanisms that have been overlooked in previous literature. First, increased triceps surae stretch in terminal stance may be used to increase proprioception and/or energy storage, while a prolonged hip extension moment in midstance compensates for a limited push-off. These result in an overall workload shift from distal to proximal joints. Clinical assessment, monitoring, and treatment of neuropathy may benefit by focusing on these specific functional alterations.

The effect of time restricted visual sensory input on asymmetry of ground reaction force components in female children

The association between visual sensory and the asymmetry index of sit-to-stand ground reaction force characteristics is not fully understood. Therefore, the purpose of this study was to investigate asymmetry index of sit-to-stand ground reaction forces, their times-to-peak, vertical loading rate, impulses, and free moment in blind and sighted children. 15 female children with congenital blindness and 30 healthy girls with no visual impairments volunteered to participate in this study. The girls with congenital blindness were placed in one group and the girls with no visual impairments were randomly divided into two groups of 15. The two condition groups consisted of, one eyes open and the other, eyes closed. The participants in the eyes closed group were asked to close their eyes for 20 min before the test, whereas those in the eyes open group kept their eyes open. Kinematic and kinetic data were collected using an eight-camera motion analysis system synchronized with two force plates embedded in the floor. A MANOVA test was run for between-group comparisons. There were no distinctive biomechanical alternations in all axes of ground reaction forces and their times-to-peak, vertical loading rate, impulses and free moments in congenital blindness and eyes closed groups compared with the eyes open group. However, eyes closed was associated with increased total time and second phase duration of sit-to-stand performance by 69% (p = 0.008) and 62% (p = 0.008), respectively. These findings reveal that individuals who are visually restricted in the short term, do not develop stereotypical movement strategies for sit-to-stand.

Gait alterations in the UAE population with and without diabetic complications using both traditional and entropy measures

Diabetic foot, one of the most common and debilitating manifestations of type 2 diabetes mellitus (T2DM), is the leading cause of worldwide non-traumatic lower extremity amputations. Diabetics who are at risk of ulceration are currently mainly identified by a thorough clinical examination of the feet, which typically does not show clear symptoms during the early stages of disease progression. In this study, we used a non-linear dynamics tool, gait entropy (GaitEN), in addition to traditional linear gait analysis methods, to investigate gait alterations amongst diabetic patients with combinations of three types of T2DM related complications: retinopathy, diabetic peripheral neuropathy (DPN) and nephropathy. Peak plantar pressure (PPP) was not significantly different in the group with DPN as compared to the control group (diabetics with no complications, CONT) in the forefoot region (DPN: mean±SD: 396±69.4kPa, CONT: 409±68.9kPa), although it was significantly lower in the heel region (DPN: mean±SD: 285±43.1.4kPa, CONT: 295±61.8kPa). On the other hand, gait entropy was significantly lower for the DPN compared to CONT group (DPN: 0.95±0.34, CONT: 1.03±0.28, p<0.05). The significant low entropy was maintained when neuropathy was combined with either retinopathy or nephropathy. For the group with all three complications (ALL-C), the entropy was higher than CONT (ALL-C: 1.07±0.26). This may indicate an intrinsic sensorimotor feedback mechanism for the DPN patients to regulate their gait. However, this feedback gets weaker as patients develop multiple complications. Further analysis with longer walking time and different speeds is needed to verify the entropy results.

Postural Control and Gait Performance in the Diabetic Peripheral Neuropathy: A Systematic Review

Purpose. The aim of this paper is to review the published studies on the characteristics of impairments in the postural control and gait performance in diabetic peripheral neuropathy (DPN). Methods. A review was performed by obtaining publication of all papers reporting on the postural control and gait performance in DPN from Google Scholar, Ovid, SAGE, Springerlink, Science Direct (SD), EBSCO Discovery Service, and Web of Science databases. The keywords used for searching were “postural control,” “balance,” “gait performance,” “diabetes mellitus,” and “diabetic peripheral neuropathy.” Results. Total of 4,337 studies were hit in the search. 1,524 studies were screened on their titles and citations. Then, 79 studies were screened on their abstract. Only 38 studies were eligible to be selected: 17 studies on postural control and 21 studies on the gait performance. Most previous researches were found to have strong evidence of postural control impairments and noticeable gait deficits in DPN. Deterioration of somatosensory, visual, and vestibular systems with the pathologic condition of diabetes on cognitive impairment causes further instability of postural and gait performance in DPN. Conclusions. Postural instability and gait imbalance in DPN may contribute to high risk of fall incidence, especially in the geriatric population. Thus, further works are crucial to highlight this fact in the hospital based and community adults.

Reliability and validity of the Lower Limb Function Questionnaire when completed by young adult orthotic and prosthetic device users

Purpose The Lower Limb Function Questionnaire (LLFQ) was developed as a self-report assessment of lower-limb functional ability for orthotic and prosthetic (O&P) device users to be suitable for a wide range of conditions, cultures, and ages. The measure aims to address an existing gap in tools for the assessment of functional ability in this population. The purpose of this study is to evaluate LLFQ reliability and validity in a sample of young adult O&P users. Methods Adolescents from a secondary school in Kenya completed the LLFQ twice, 6 d apart, and test-retest reliability was assessed using intra-class correlation coefficients. Validity evaluations involved Timed Up-and-Go, 6-min walk, 6-min obstacle course, and/or spatiotemporal gait assessments. Oxygen consumption was measured during walk tests. Associations between the LLFQ and each measure were evaluated using Pearson correlation coefficients for construct validity. Results LLFQ reliability was acceptable (ICC = 0.79, 95% CIs 0.64-0.89). Construct validity was demonstrated via moderate correlation (r  >  0.60) with obstacle course distance, gait velocity, stride length, and stance/single support/double support percent of gait cycle. Conclusions Both LLFQ reliability and validity were acceptable in the sample of youth in Kenya. Further testing is required to determine applicability in other cultural contexts. Implications for Rehabilitation The LLFQ may be clinically useful across a variety of cultures and conditions to provide feedback on the effectiveness of rehabilitative treatment or assistive devices for youth with lower limb impairments. The LLFQ may enable specific strengths and challenges to lower limb function to be identified to enable planning of well-targeted rehabilitation.

Mobility-Related Consequences of Reduced Lower-Extremity Peripheral Nerve Function with Age: A Systematic Review

The objective of this study is to systematically review the relationship between lower-extremity peripheral nerve function and mobility in older adults. The National Library of Medicine (PubMed) was searched on March 23, 2015 with no limits on publication dates. One reviewer selected original research studies of older adults (≥65 years) that assessed the relationship between lower-extremity peripheral nerve function and mobility-related outcomes. Participants, study design and methods of assessing peripheral nerve impairment were evaluated and results were reported and synthesized. Eight articles were identified, including 6 cross-sectional and 2 longitudinal studies. These articles investigated 6 elderly cohorts (4 from the U.S. and 2 from Italy): 3 community-dwelling (including 1 with only disabled women and 1 without mobility limitations at baseline), 1 with both community-dwelling and institutionalized residents, 1 from a range of residential locations, and 1 of patients with peripheral arterial disease. Mean ages ranged from 71-82 years. Nerve function was assessed by vibration threshold (n=2); sensory measures and clinical signs and symptoms of neuropathy (n=2); motor nerve conduction (n=1); and a combination of both sensory measures and motor nerve conduction (n=3). Each study found that worse peripheral nerve function was related to poor mobility, although relationships varied based on the nerve function measure and mobility domain assessed. Six studies found that the association between nerve function and mobility persisted despite adjustment for diabetes. Evidence suggests that peripheral nerve function impairment at various levels of severity is related to poor mobility independent of diabetes. Relationships varied depending on peripheral nerve measure, which may be particularly important when investigating specific biological mechanisms. Future research needs to identify risk factors for peripheral nerve decline beyond diabetes, especially those common in late-life and modifiable. Interventions to preserve nerve function should be investigated with regard to their effect on postponing or preventing disability in older adults.

Quantitative assessment of early biomechanical modifications in diabetic foot patients: the role of foot kinematics and step width

BACKGROUND

Forefoot ulcers (FU) are one of the most disabling and relevant chronic complications of diabetes mellitus (DM). In recent years there is emerging awareness that a better understanding of the biomechanical factors underlying the diabetic ulcer could lead to improve the management of the disease, with significant socio-economic impacts. Our purpose was to try to detect early biomechanical factors associated with disease progression.

METHODS

Thirty subjects (M/F: 22/8; mean age ± SD: 61,84 ± 10 years) with diagnosis of type II DM were included. The participants were divided into 3 groups (10 subjects per group) according to the stage of evolution of the disease: Group 1, subjects with newly diagnosed type II DM, without clinical or instrumental diabetic peripheral neuropathy (DPN) nor FU (group called "DM"); Group 2, with DPN but without FU (group called "DPN"); Group 3, with DPN and FU (group called "DNU"). All subjects underwent 3-D Gait Analysis during walking at self-selected speed, measuring spatio-temporal, kinematic and kinetic parameters and focusing on ankle and foot joints. The comparative analysis of values between groups was performed using 1-way ANOVA. We also investigated group to group differences with Tukey HSD test. The results taken into consideration were those with a significance of P < 0,05. 95 % confidence interval was also calculated.

RESULTS

A progressive and significant trend of reduction of ROM in flexion-extension of the metatarso-phalangeal joint (P = 0.0038) and increasing of step width (P = 0.0265) with the advance of the disease was evident, with a statistically significant difference comparing subjects with recently diagnosed diabetes mellitus and subjects with diabetic neuropathy and foot ulcer (P = 0.0048 for ROM and P = 0.0248 for step width at Tukey's test).

CONCLUSIONS

The results provide evidence that foot segmental kinematics, along with step width, can be proposed as simple and clear indicators of disease progression. This can be the starting point for planning more targeted strategies to prevent the occurrence and the recurrence of a FU in diabetic subjects.

A comparison of the effects of visual deprivation and regular body weight support treadmill training on improving over-ground walking of stroke patients: a multiple baseline single subject design

The body-weight-support treadmill (BWST) is commonly used for gait rehabilitation, but other forms of BWST are in development, such as visual-deprivation BWST (VDBWST). In this study, we compare the effect of VDBWST training and conventional BWST training on spatiotemporal gait parameters for three individuals who had hemiparetic strokes. We used a single-subject experimental design, alternating multiple baselines across the individuals. We recruited three individuals with hemiparesis from stroke; two on the left side and one on the right. For the main outcome measures we assessed spatiotemporal gait parameters using GAITRite, including: gait velocity; cadence; step time of the affected side (STA); step time of the non-affected side (STN); step length of the affected side (SLA); step length of the non-affected side (SLN); step-time asymmetry (ST-asymmetry); and step-length asymmetry (SL-asymmetry). Gait velocity, cadence, SLA, and SLN increased from baseline after both interventions, but STA, ST-asymmetry, and SL-asymmetry decreased from the baseline after the interventions. The VDBWST was significantly more effective than the BWST for increasing gait velocity and cadence and for decreasing ST-asymmetry. VDBWST is more effective than BWST for improving gait performance during the rehabilitation for ground walking.

The Combined Extract of Zingiber officinale and Zea mays (Purple Color) Improves Neuropathy, Oxidative Stress, and Axon Density in Streptozotocin Induced Diabetic Rats

Based on the protective effect of the combined extract of purple waxy corn and ginger (PWCG) on oxidative stress related disorders in diabetic condition, we aimed to determine the effect of PWCG on the functional, biochemical, and structural change of the lesion nerve in streptozotocin- (STZ-) diabetic rats. PWCG at doses of 100, 200, and 300 mg·kg⁻¹ BW were orally given to STZ-diabetic rats which were subjected to chronic constriction (CCI) at right sciatic nerve for 21 days. The blood sugar was assessed before and at the end of study whereas the sciatic function index (SFI), paw withdrawal threshold intensity (PWTI), and paw withdrawal latency (PWL) were assessed every 3 days until the end of study. At the end of study, the determination of nerve conduction velocity (NCV), axon density, oxidative stress status, and aldose reductase (AR) activity of the lesion nerve were performed. It was found that PWCG improved SFI, PWTI, PWL, and NCV together with the improved oxidative stress status and the axon density in the lesion nerve. No changes of AR activity or blood sugar level were observed. Therefore, PWCG might improve the functional and structural changes in STZ-diabetic rats plus CCI via the improved oxidative stress status.

Interactions between cognitive and sensory load while planning and controlling complex gait adaptations in Parkinson's disease

Background

Recent research has argued that removal of relevant sensory information during the planning and control of simple, self-paced walking can result in increased demand on central processing resources in Parkinson’s disease (PD). However, little is known about more complex gait tasks that require planning of gait adaptations to cross over an obstacle in PD.

Methods

In order to understand the interaction between availability of visual information relevant for self-motion and cognitive load, the current study evaluated PD participants and healthy controls while walking toward and stepping over an obstacle in three visual feedback conditions: (i) no visual restrictions; (ii) vision of the obstacle and their lower limbs while in complete darkness; (iii) vision of the obstacle only while in complete darkness; as well as two conditions including a cognitive load (with a dual task versus without a dual task). Each walk trial was divided into an early and late phase to examine changes associated with planning of step adjustments when approaching the obstacle.

Results

Interactions between visual feedback and dual task conditions during the obstacle approach were not significant. Patients with PD had greater deceleration and step time variability in the late phase of the obstacle approach phase while walking in both dark conditions compared to control participants. Additionally, participants with PD had a greater number of obstacle contacts when vision of their lower limbs was not available specifically during the dual task condition. Dual task performance was worse in PD compared to healthy control participants, but notably only while walking in the dark regardless of visual feedback.

Conclusions

These results suggest that reducing visual feedback while approaching an obstacle shifts processing to somatosensory feedback to guide movement which imposes a greater demand on planning resources. These results are key to fully understanding why trips and falls occur in those with PD.

Pedobarography in diagnosis and clinical application

Introduction:

Pedobarography as a new diagnostic tool enables measuring the pressure between the foot and the floor during dynamic loading. Dynamic analysis of the foot shows advantage over static analysis due to its capabilities for detecting high load points in certain diseases and in certain phases of walking. Pedobarography as a new method in the context of rehabilitation include wide range of clinical entities.

Goal:

To show the advantages of pedobarography as new diagnostic and rehabilitation method in prevention programs.

Material and methods:

A prospective study included 100 patients with diabetes mellitus type 2. Research was conducted in the Primary Health Care Center of the Sarajevo Canton and the Center for Physical Medicine and Rehabilitation. The test parameters were: Test of balance–symmetric load for the test, the number of comorbidity, clinical examination of foot deformity, test with 10 g monofilament, HbA1c. From the total sample 45 patients (Group I) were selected, aged 50-65 years, which underwent pedobarography (on the appliance Novel Inc., Munich with EMED™ platform) and robotic fabrication of individual orthopedic insoles, followed by control pedobarography. Plantar pressure was determined using standard pedobarography, computer recorded parameters: peak pressure (kPa), force (Ns), area (cm).

Results:

The average age of the respondents was 59.4±11.38 years; altered results on the balance test were present in 34% of patients; 61% of respondents have ≤2 comorbidity. In the total sample, the average number of foot deformity was 2.84. Flat feet have 66% of respondents, and valgus position 57%. The average HbA1c values were 7.783±1.58% (min.5–max.15.0). All subjects (45) after the first, and after the second measurement of peak pressure, have values above 200 kPa, or are in the designated zone of peak pressure that needs to be corrected. In a study was determined the correlation between the number of deformities and peak pressure, the number of deformities and the area upon which plantar pressure act, test with 10g monofilament and peak pressure.

Conclusion:

Within the framework of prevention programs early diagnosis, detection of sensitivity disorders, adequate treatment and taking load from the feet with the help of pedobarography, are of great importance for the patient suffering from diabetes

Assessment of diabetic polyneuropathy and plantar pressure in patients with diabetes mellitus in prevention of diabetic foot

Introduction:

Risk assessment for development foot ulcer in diabetics is a key aspect in any plan and program for prevention of non-traumatic amputation of lower extremities.

Material and methods:

In the prospective research to assessed diabetic neuropathy in diabetic patients, to determined the dynamic function of the foot (plantar pressure), by using pedobarography (Group I), and after the use of orthopedic insoles with help of pedobarography, to determined the connection between the risk factors: deformity of the foot, limited joint movements, diabetic polyneuropathy, plantar pressure in effort preventing changes in the diabetic foot.

Results:

Out of 1806 patients, who are registered in one Team of family medicine examined 100 patients with diabetes mellitus Type 2. The average age of subjects was 59.4, SD11.38. The average HbA1c was 7.78% SD1.58. Combining monofilament and tuning fork tests, the diagnosis of polyneuropathy have 65% of patients. Comparing Test Symptom Score individual parameters between the first and second measurement, using pedobarography, in Group I, statistically significant difference was found for all of the assessed parameters: pain, burning sensation, paresthesia and insensitivity (p<0,05). The measurements of peak pressure, both first and the second measurement, for all of the subjects in Group I(45) show values above 200kPa. That’s a level of pressure that needs to be corrected. The study finds correlation between the foot deformation, diabetic polyneuropathy and plantar pressure (p>0,05).

Conclusion:

A detail clinical exam of diabetic food in a family doctor office equipped with pedobarography (plantar pressure measurements), use of orthopedic insoles, significantly reduces clinical symptoms of diabetic polyneuropathy in patients with diabetes.

Intralimb coordination as a sensitive indicator of motor-control impairment after spinal cord injury

Background: Recovery of walking function after neurotrauma, e.g., after spinal cord injury, is routinely captured using standardized walking outcome measures of time and distance. However, these measures do not provide information on possible underlying mechanisms of recovery, nor do they tell anything about the quality of gait. Subjects with an incomplete spinal cord injury are a very heterogeneous group of people with a wide range of functional impairments. A stratification of these subjects would allow increasing sensitivity for hypothesis testing and a more targeted treatment strategy.

Methods: The gait of incomplete spinal cord injured subjects was compared to healthy control subjects by analyzing kinematic data obtained by a 3-D motion capture system. Hip–knee angle-angle plots (cyclograms) informed on the qualitative aspect of gait and the intralimb coordination. Features of the cyclogram, e.g., shape of the cyclogram, cycle-to-cycle consistency and its modulation due to changes in walking speed were discerned and used to stratify spinal cord injured subjects.

Results: Spinal cord injured subjects were unable to modulate their cyclogram configuration when increasing speed from slow to preferred. Their gait quality remained clearly aberrant and showed even higher deviations from normal when walking at preferred speed. Qualitative categorization of spinal cord injured subjects based on their intralimb coordination was complemented by quantitative measures of cyclogram shape comparison.

Discussion: Spinal cord injured subjects showed distinct distortions of intralimb coordination as well as limited modulation to changes in walking speed. The specific changes of the cyclograms revealed complementary insight in the disturbance of lower-limb control in addition to measures of time and distance and may be a useful tool for patient categorization and stratification prior to clinical trial inclusion.

Diabetic foot and exercise therapy: step by step the role of rigid posture and biomechanics treatment

Lower extremity ulcers represent a serious and costly complication of diabetes mellitus. Many factors contribute to the development of diabetic foot. Peripheral neuropathy and peripheral vascular disease are the main causes of foot ulceration and contribute in turn to the growth of additional risk factors such as limited joint mobility, muscular alterations and foot deformities. Moreover, a deficit of balance, posture and biomechanics can be present, in particular in patients at high risk for ulceration. The result of this process may be the development of a vicious cycle which leads to abnormal distribution of the foot's plantar pressures in static and dynamic postural conditions. This review shows that some of these risk factors significantly improve after a few weeks of exercise therapy (ET) intervention. Accordingly it has been suggested that ET can be an important weapon in the prevention of foot ulcer. The aim of ET can relate to one or more alterations typically found in diabetic patients, although greater attention should be paid to the evaluation and possible correction of body balance, rigid posture and biomechanics. Some of the most important limitations of ET are difficult access to therapy, patient compliance and the transitoriness of the results if the training stops. Many proposals have been made to overcome such limitations. In particular, it is important that specialized centers offer the opportunity to participate in ET and during the treatment the team should work to change the patient's lifestyle by improving the execution of appropriate daily physical activity.

Sensory loss and walking speed related factors for gait alterations in patients with peripheral neuropathy

BACKGROUND

Walking instability and a higher risk of falls are common in patients with peripheral neuropathy. However, it remains uncertain as to whether alterations in neuropathic gait are directly related to deficient sensory locomotion control or due to a slowing of walking speed. By means of a multi-speed gait assessment we determined factors related to sensory loss and walking speed that cause changes in the gait pattern of neuropathic patients.

METHODS

Walking patterns of 18 neuropathic patients (70.7±2.4 years, 6 females) and 18 age- and gender-matched healthy subjects (70.4±2.4 years, 6 females) were recorded on a pressure-sensitive gait carpet for three different locomotion speeds (i.e. slow, preferred and fast) and while walking with eyes closed. Mean temporospatial gait parameters and gait variability were analyzed. The relationship between gait alterations and the history of falls in patients was evaluated.

RESULTS

Alterations in the mean locomotion pattern of neuropathic patients were mainly related to reduced walking speed. However, prolonged double support times (p<0.001), widened base widths (p=0.001) and increased gait variability (p<0.001) during slow walking or with eyes closed appeared to be directly linked to peripheral sensory loss in patients. Increased gait variability was predictive for the presence of self-reported falls in the past (p=0.029).

CONCLUSIONS

Sensory-loss-related prolongation of double support phases in neuropathic patients suggests a compensatory strategy to improve restabilization during locomotion. Moreover, widened base widths and increased gait variability point to an increased risk of falls. They occur primarily when patients are forced to reduce their walking speed or when visual feedback is disturbed.

The impact of footwear and walking distance on gait stability in diabetic patients with peripheral neuropathy

BACKGROUND

We explored gait differences in patients with diabetes and peripheral neuropathy (DPN) and aged-matched controls over short and long walking distances. The potential benefit of footwear for improving gait in patients with DPN was also explored.

METHODS

Twelve patients with DPN and eight controls walked at their habitual speed over short (7 m) and long (20 m) distances under two conditions: barefoot and regular shoes. A validated system of body-worn sensors was used to extract spatiotemporal gait parameters. Neuropathy severity was quantified using vibratory perception threshold measured at the great toe.

RESULTS

Gait deterioration in the DPN group was observed during all of the walking trials. However, the difference between patients with DPN and participants in the control group achieved statistical significance only during long walking distance trials. Shod and barefoot double support times were longer in the DPN group during long walking distances (>20%, P = .03). Gait unsteadiness, defined as coefficient of variation of gait velocity, was also significantly higher in the DPN group when barefoot walking over long distances (83%, P = .008). Furthermore, there was a high correlation between neuropathy severity and gait unsteadiness best demonstrated during the barefoot walking/long walking distance condition (r = 0.77, P < .001). The addition of footwear improved gait steadiness in the DPN group by 46% (P = .02). All differences were independent of age, sex, and body mass index (P > .05).

CONCLUSIONS

This study suggests that gait alteration in patients with DPN is most pronounced while walking barefoot over longer distances and that footwear may improve gait steadiness in patients with DPN.

Complications of the diabetic foot

The diabetic foot is at high risk for complications because of its role in ambulation. Peripheral neuropathy and peripheral vascular disease can lead to chronic foot ulcers, which are at high risk for infection, in part attributable to areas of high pressure caused by lack of tolerance of the soft tissue and bone and joint deformity. If left untreated, infection and ischemia lead to tissue death, culminating in amputation. Treatment strategies include antibiosis, topical therapies, offloading, debridement, and surgery. A multidisciplinary team approach is necessary in the prevention and treatment of complications of the diabetic foot.

Lower leg muscle strengthening does not redistribute plantar load in diabetic polyneuropathy: a randomised controlled trial

Background

Higher plantar pressures play an important role in the development of plantar foot ulceration in diabetic polyneuropathy and earlier studies suggest that higher pressures under the forefoot may be related to a decrease in lower leg muscle strength. Therefore, in this randomised controlled trial we evaluated whether lower-extremity strength training can reduce plantar pressures in diabetic polyneuropathy.

Methods

This study was embedded in an unblinded randomised controlled trial. Participants had diabetes and polyneuropathy and were randomly assigned to the intervention group (n = 48) receiving strength training during 24 weeks, or the control group (n = 46) receiving no intervention. Plantar pressures were measured in both groups at 0, 12, 24 and 52 weeks. A random intercept model was applied to evaluate the effects of the intervention on peak pressures and pressure–time-integrals, displacement of center-of-pressure and the forefoot to rearfoot pressure–time-integral-ratio.

Results

Plantar pressure patterns were not affected by the strength training. In both the intervention and control groups the peak pressure and the pressure–time-integral under the forefoot increased by 55.7 kPa (95% CI: 14.7, 96.8) and 2.0 kPa.s (95% CI: 0.9, 3.2) over 52 weeks, respectively. Both groups experienced a high number of drop-outs, mainly due to deterioration of health status and lower-extremity disabilities.

Conclusions

Plantar pressures under the forefoot increase progressively over time in people with diabetic polyneuropathy, but in this study were not affected by strength training. Future intervention studies should take this increase of plantar pressure into account and alternative interventions should be developed to reduce the progressive lower extremity problems in these patients.

Trial registration

This study was embedded in a clinical trial with trial number NCT00759265.

Strength training affects lower extremity gait kinematics, not kinetics, in people with diabetic polyneuropathy

Increased forefoot loading in diabetic polyneuropathy plays an important role in the development of plantar foot ulcers and can originate from alterations in muscle strength, joint moments and gait pattern. The current study evaluated whether strength training can improve lower extremity joint moments and spatiotemporal gait characteristics in patients with diabetic polyneuropathy. An intervention group receiving strength training during 24 weeks and a control group receiving no intervention. Measurements were performed in both groups at t=0, t=12, t=24 and t=52 weeks at an individually preferred and standardized imposed gait velocity. The strength training did not affect the maximal amplitude of hip, knee and ankle joint moments, but did result in an increase in stance phase duration, stride time and stride length of approximately 5%, during the imposed gait velocity. In addition, both groups increased their preferred gait velocity over one year. Future longitudinal studies should further explore the possible effects of strength training on spatiotemporal gait characteristics. The current study provides valuable information on changes in gait velocities and the progressive lower extremity problems in patients with polyneuropathy.

Plantar pressure distribution patterns of individuals with prediabetes in comparison with healthy individuals and individuals with diabetes

BACKGROUND

Since elevated mechanical stress along with loss of plantar protective sensation are considered relevant factors in skin breakdown resulting in diabetic foot ulcerations, the assessment of plantar pressure is important for the prevention of diabetic foot complications. Prediabetes subjects are at risk of chronic hyperglycemia complications, among them neuropathy, but information about plantar loading in this population is not available. We aimed to compare baropodometric parameters of individuals with prediabetes versus healthy persons and persons with diabetes mellitus (DM).

METHODS

Baropodometric data from 73 subjects (15 with prediabetes (pre-DM), 28 with type 2 DM, 30 healthy) aged between 29 and 69 years of both genders were registered through a pressure platform with self-selected gait speed and first-step protocol. Peak plantar pressure, stance time, percentage of contact time, percentage of contact area and pressure-time integral were assessed in five plantar foot regions: heel, midfoot, metatarsals, hallux, and toes 2 to 5. Groups were compared by one-way analysis of variance with Scheffé post hoc (α = 0.05).

RESULTS

Age, body mass index, gender, and arch height index did not differ between groups. Pre-DM and DM subjects presented increased peak pressure and pressure-time integral in metatarsals (p = .010; p > .001), as well as increased percentage of contact time in midfoot (p = .006) and metatarsals (p = .004) regions when compared with healthy subjects. Stance time was significantly higher (p = .017) in DM subjects.

CONCLUSIONS

Pre-DM subjects seem to exhibit an altered plantar pressure distribution pattern similar to that often found in DM subjects.

Diabetic peripheral neuropathy and gait: does footwear modify this association?

BACKGROUND

Gait-related fall risk is the leading cause of mortality among patients with diabetes, especially those older than 65 years. Deterioration in balance and loss of protective sensation in lower extremities contribute significantly to fall risk in patients with diabetic peripheral neuropathy (DPN). This study aimed to explore the impact of neuropathy and foot ulcer on gait.

METHODS

We recruited 39 participants (age, 56.9 ± 8.2 years; body mass index, 29.6.3 ± 4.7 kg/m2), including 15 DPN patients without foot ulcers, 16 DPN patients with foot ulcers, and 8 healthy aged-matched controls. Patients with active foot ulcers wore an offloading device during gait examination, including removable cast walker.

RESULTS

Results suggest that neuropathy alters gait mainly by increasing gait initiation, gait variability (coefficient of variation of gait velocity), and double support (DS) time, while reducing knee range of motion and center of mass sway (p < .05). Interestingly, the presence of foot ulcer does not impact gait velocity (p > .1) but enhances some of the gait parameters such as gait variability and DS time.

CONCLUSIONS

This study demonstrates that neuropathy deteriorates gait, but the presence of foot ulcers does not alter gait parameters further than neuropathy. In addition, patients with foot ulcers demonstrated a better gait compared with DPN patients without ulcers. We speculate that offloading footwear may be enhancing the somatosensory feedback from sensate skin, thereby positively affecting gait parameters. A study with a larger sample is required to explore the effect of prescribed footwear in the DPN population in order to validate the findings of this research study.

Influence of lower extremity sensory function on locomotor adaptation following stroke: a review

Following stroke, people commonly demonstrate locomotor impairments including reduced walking speed and spatiotemporal asymmetry. Rehabilitation programs have been effective in increasing gait speed, but spatiotemporal asymmetry has been more resistant to change. The inability to modify gait patterns for improved symmetry may be related, in part, to impairments in lower extremity sensation. Assessment of lower extremity sensory impairments in people post stroke, including cutaneous and proprioceptive sensation, has been insufficiently studied. Conventional rehabilitation programs, including body weight-supported walking or robotic assistance, that modify sensory feedback intended to alter lower extremity movement patterns have shown limited success in improving gait symmetry. Rehabilitation programs that amplify specific gait asymmetries have demonstrated the potential to ultimately produce more symmetric gait, presumably by allowing individuals post stroke to more readily perceive their gait asymmetry. The effectiveness of such error augmentation paradigms, however, may be influenced by lower extremity sensation and the ability of the central nervous system to be aware of altered lower extremity movement. The purpose of this review is to critically examine the literature on lower extremity sensory function and its influence on gait adaptation in people post stroke.

Increased gait variability in diabetes mellitus patients with neuropathic pain

AIMS

Gait dysfunction in subjects with diabetes mellitus (DM) contributes to falling and subsequent injuries. Using a portable device (GaitMeter™), we measured gait parameters in DM patients with and without diabetic peripheral neuropathy (DPN) during flat surface walking. We hypothesized that DM patients with DPN and neuropathic pain (NeP) would have greater gait step variability than those with DPN without NeP.

METHODS

Subjects with DPN and at least moderate NeP (DPN-P), DPN without NeP (DPN-NoP), DM without DPN, and control subjects without DM were assessed. Our outcome measure was gait variability for step length and velocity. DPN severity was quantified using the Toronto Clinical Scoring System and the Utah Early Neuropathy Score. Falls and their outcomes were retrospectively quantified.

RESULTS

Each cohort contained≥20 subjects. Durations of DM and HbA1C were greatest amongst DPN cohorts. DPN-P participants had greater variability of step length and step velocity, except for DM only participants. DPN-P participants also reported greater risk of hospitalizations for fall-related injuries, and greater fear of falling. Modest negative relationships emerged for step length with step velocity, reported falls and pain severity.

CONCLUSIONS

NeP contributes to gait variability, potentially contributing to the risk of falling in DM patients.

Performance-based physical functioning and peripheral neuropathy in a population-based cohort of women at midlife

Peripheral neuropathy is underappreciated as a potential cause of functional limitations. In the present article, we assessed the cross-sectional association between peripheral neuropathy and physical functioning and how the longitudinal association between age and functioning differed by neuropathy status. Physical functioning was measured in 1996-2008 using timed performances on stair-climb, walking, sit-to-stand, and balance tests at the Michigan site of the Study of Women's Health Across the Nation, a population-based cohort study of women at midlife (n = 396). Peripheral neuropathy was measured in 2008 and defined as having an abnormal monofilament test result or 4 or more symptoms. We used linear mixed models to determine whether trajectories of physical functioning differed by prevalent neuropathy status. Overall, 27.8% of the women had neuropathy. Stair-climb time differed by neuropathy status (P = 0.04), and for every 1-year increase in age, women with neuropathy had a 1.82% (95% confidence interval: 1.42, 2.21) increase compared with a 0.95% (95% confidence interval: 0.71, 1.20) increase for women without neuropathy. Sit-to-stand time differed by neuropathy status (P = 0.01), but the rate of change did not differ. No differences between neuropathy groups were observed for the walk test. For some performance-based tasks, poor functioning was maintained or exacerbated for women who had prevalent neuropathy. Peripheral neuropathy may play a role in physical functioning limitations and future disability.

Muscle strength and ankle mobility for the gait parameters in diabetic neuropathies

AIMS

To evaluate the spatio-temporal variables of gait and the isometric muscle strength component of the ankle in patients with peripheral diabetic neuropathy. Also, verify the relationship between these variables and gait parameters.

METHODS

This study involved 25 diabetic peripheral neuropathy (DPN) participants (62.4±8.36 years) and 27 age-matched healthy control individuals (64.48±6.21 years). The assessment of the spatio-temporal parameters of gait was performed using an electronic baropodometry treadmill. Prior to the collection data, each participant was instructed to walk on the treadmill in her/his habitual self-selected speed.

RESULTS

Diabetic neuropathy group showed impairment of gait, with a smaller stride and length speed of the cycle, and increased duration of support time. Restricted dorsiflexion mobility and increased plantarflexion mobility were found, with a decrease in muscle strength of the dorsiflexors and plantiflexors. There was a significant relationship between plantiflexor muscle strength and the length and speed of the gait cycle. Also the muscle strengths of the plantiflexors and dorsiflexors, and the range of motion of dorsiflexion were predictors of gait performance.

CONCLUSIONS

The ankle, muscle strength and ankle mobility variables could explain changes in gait speed and range of motion in patients with DPN, allowing for the application of preventive strategies.

Diagnostic accuracy of fall risk assessment tools in people with diabetic peripheral neuropathy

BACKGROUND

Diabetic peripheral neuropathy affects nearly half of individuals with diabetes and leads to increased fall risk. Evidence addressing fall risk assessment for these individuals is lacking.

OBJECTIVE

The purpose of this study was to identify which of 4 functional mobility fall risk assessment tools best discriminates, in people with diabetic peripheral neuropathy, between recurrent "fallers" and those who are not recurrent fallers.

DESIGN

A cross-sectional study was conducted.

SETTING

The study was conducted in a medical research university setting.

PARTICIPANTS

The participants were a convenience sample of 36 individuals between 40 and 65 years of age with diabetic peripheral neuropathy.

MEASUREMENTS

Fall history was assessed retrospectively and was the criterion standard. Fall risk was assessed using the Functional Reach Test, the Timed "Up & Go" Test, the Berg Balance Scale, and the Dynamic Gait Index. Sensitivity, specificity, positive and negative likelihood ratios, and overall diagnostic accuracy were calculated for each fall risk assessment tool. Receiver operating characteristic curves were used to estimate modified cutoff scores for each fall risk assessment tool; indexes then were recalculated.

RESULTS

Ten of the 36 participants were classified as recurrent fallers. When traditional cutoff scores were used, the Dynamic Gait Index and Functional Reach Test demonstrated the highest sensitivity at only 30%; the Dynamic Gait Index also demonstrated the highest overall diagnostic accuracy. When modified cutoff scores were used, all tools demonstrated improved sensitivity (80% or 90%). Overall diagnostic accuracy improved for all tests except the Functional Reach Test; the Timed "Up & Go" Test demonstrated the highest diagnostic accuracy at 88.9%.

LIMITATIONS

The small sample size and retrospective fall history assessment were limitations of the study.

CONCLUSIONS

Modified cutoff scores improved diagnostic accuracy for 3 of 4 fall risk assessment tools when testing people with diabetic peripheral neuropathy.

LOWER LIMB JOINT POSITION SENSE IN PATIENTS WITH TYPE II DIABETES MELLITUS

Diabetes mellitus (DM), of which type II has been described as an international epidemic, is a major cause of death. Diabetic peripheral neuropathy (PN) is a condition secondary to hyperglycemia, where progressive loss of peripheral nerve function, including sensory and motor functions, occurs over time. Early detection of PN-related impairments may be helpful for the management of patients with DM. Among the methods for the evaluation of these impairments, only that for joint position sense (JPS) requires both motor and sensory involvement. The purpose of the current study was to compare the JPS of the lower limb joints in patients with no or mild diabetic PN to those of normal controls both during weight-bearing (WB) and non-weight-bearing (NWB) conditions using 3D motion analysis methods. The results supported the hypothesis that in well controlled diabetic patients with no or mild PN, JPS deficits can be found only at the ankle joint during WB conditions, resulting in overestimation of dorsiflexion angles. This suggests that at the very early stage of development of diabetic PN, distal joint involvement precedes that of proximal joints. Early detection of these changes, through the assessment of the JPS for all the lower limb joints under both NWB and WB conditions, will be helpful for the development of clinical preventive and treatment programs for patients with DM, even if their glucose level are well controlled. Gait and balance training in these patients should emphasize proprioception training exercises during WB conditions.

Abnormal muscle activation during gait in diabetes patients with and without neuropathy

The World Health Organization warns that, in 2000, as many as 33 million Europeans suffered from diabetes, approximately 15% will likely develop foot ulcers, and approximately 15-20% of these patients will face lower-extremity amputation. Changes in some gait parameters that appear to be specific in diabetes have been identified in the literature: shorter stride length, reduced walking speed, and altered lower limb and trunk mobility. The present study aimed at evaluating the role of altered muscle activity in gait alterations of diabetic subjects with and without neuropathy. This study involved 50 subjects: 10 controls (BMI 24.4 ± 2.8, age 61.2 ± 5.07), 20 diabetics (BMI 26.4 ± 2.5, age 56.53 ± 13.29) and 20 neuropathics (BMI 26.8 ± 3.4, age 61.2 ± 7.7). The electrical activity of six muscles was collected bilaterally on the lower limb during gait: gluteus medius, rectus femoris, tibialis anterior, peroneous longus, gastrocnemius lateralis, and extensor digitorum communis. Electromyographic activity was represented through linear envelopes. Time and space parameters were also evaluated by means of two Bertec force plates and a six cameras motion capture system (BTS, 60-120 Hz). At initial contact and loading response, an early peak of rectus femoris activity occurred in diabetic subjects with and without neuropathy. During midstance a delay of gastrocnemius activity was observed in diabetic non-neuropathic subjects. During terminal swing a delay of rectus femoris and gluteus medius activity was seen in diabetic non-neuropathic subjects'. The results suggest that important muscle activity deviations are present in diabetic subjects although these are not directly related to neuropathy.

Foot anatomy specialization for postural sensation and control

Anthropological and biomechanical research suggests that the human foot evolved a unique design for propulsion and support. In theory, the arch and toes must play an important role, however, many postural studies tend to focus on the simple hinge action of the ankle joint. To investigate further the role of foot anatomy and sensorimotor control of posture, we quantified the deformation of the foot arch and studied the effects of local perturbations applied to the toes (TOE) or 1st/2nd metatarsals (MT) while standing. In sitting position, loading and lifting a 10-kg weight on the knee respectively lowered and raised the foot arch between 1 and 1.5 mm. Less than 50% of this change could be accounted for by plantar surface skin compression. During quiet standing, the foot arch probe and shin sway revealed a significant correlation, which shows that as the tibia tilts forward, the foot arch flattens and vice versa. During TOE and MT perturbations (a 2- to 6-mm upward shift of an appropriate part of the foot at 2.5 mm/s), electromyogram (EMG) measures of the tibialis anterior and gastrocnemius revealed notable changes, and the root-mean-square (RMS) variability of shin sway increased significantly, these increments being greater in the MT condition. The slow return of RMS to baseline level (>30 s) suggested that a very small perturbation changes the surface reference frame, which then takes time to reestablish. These findings show that rather than serving as a rigid base of support, the foot is compliant, in an active state, and sensitive to minute deformations. In conclusion, the architecture and physiology of the foot appear to contribute to the task of bipedal postural control with great sensitivity.

Electromyography and kinematic changes of gait cycle at different cadences in diabetic neuropathic individuals

INTRODUCTION

Changes in gait cadence caused by challenging situations in daily life might induce higher demand for strength and propulsion in diabetic neuropathic (DN) subjects.

METHODS

Forty-six subjects (healthy and DN) walked at two cadences (self-selected and 25% higher). Kinematic and electromyographic data were obtained from lower limbs and compared across the gait cycle.

RESULTS

DN subjects showed a delayed peak in plantarflexor activity along the whole cycle (irrespective of cadence) compared with healthy subjects. However, during the imposed cadence, DN individuals showed reduced ankle range of motion along the entire cycle compared with the self-selected condition and healthy individuals walking at both cadences (P = 0.002).

CONCLUSIONS

These findings suggest that when diabetic individuals face a new challenging situation that induces a higher demand for muscle strength and propulsion, the necessary range of motion and neuromuscular control around distal joints are insufficient.

The influence of stride-length on plantar foot-pressures and joint moments

PURPOSE

Joint moments have been acknowledged as key factors in understanding gait abnormalities. Gait velocity is further known to affect joint moments and foot pressures. Keeping gait velocity constant is thus a strategy to cancel out the influence of different preferred gait speed between groups. But even if gait velocity is controlled, individuals can choose different stride length-stride frequency combinations to cope with an imposed gait velocity.

SCOPE

To understand the influence of stride frequency-stride length on joint moments and plantar pressures.

METHODS

Twenty healthy young adults had to cross an 8m walkway with a walking speed of 1.3ms(-1). The wooden walkway was equipped with a force and a pressure platform. While walking speed was kept constant each participant walked with five different imposed stride lengths (SL): preferred (SL0); with a decrease of 10% (SL-10); with a decrease of 20% (SL-20); with an increase of 10% (SL+10) and with an increase of 20% (SF+20).

RESULTS

Ankle and knee joint moments significantly decreased with a decrease in SL. A significant (p<.05) lower peak pressure was achieved with a decreased SL under the heel, toes and midfoot.

DISCUSSION/CONCLUSION

The results showed that a change in stride lengths alters both, joint moments and foot pressures with clinically interesting indications. Redistribution of joint moments in the elderly for example might rather result from decreased SL than from age.

Análise do impacto mecânico nas próteses de um sujeito bi-amputado durante a marcha

Observa-se o aumento do uso da acelerometria (medida de impactos) na aplicação clínica, especialmente para estudos da marcha acoplando-se os acelerômetros na tíbia. Entretanto, não se tem observado estudos sobre os efeitos dessas vibrações no sistema locomotor de usuários de prótese do membro inferior. O objetivo deste estudo foi medir a quantidade de impacto durante a marcha de um sujeito amputado bilateral transtibial. As coletas foram realizadas durante a marcha do sujeito caminhando a 4 km/h em uma distância de 8 metros com dois acelerômetros piezoelétricos uniaxiais fixados em dois locais distintos da prótese: inicialmente nos encaixes das próteses e posteriormente fixou-se nas hastes metálicas. Utilizou-se estatística descritiva exploratória com Anova One-Way e Post Hoc de Tukey. Constatou-se diferenças significativas com o teste Anova One-Way entre as 10 aquisições em cada local de fixação do acelerômetro. Através do Post Hoc de Tukey observou-se maiores picos de aceleração no encaixe esquerdo (p < 0,005), indicando uma maior admissão de impacto pelo coto esquerdo que possuía maior comprimento. Os maiores picos de aceleração médio encontrados durante a marcha foram: 3,57g para a prótese direita com o acelerômetro fixado na haste metálica e 5,70g para a prótese esquerda com a fixação no encaixe da prótese. Conclui-se que esta metodologia de avaliação pode ser utilizada para acompanhar o processo de reabilitação protética de sujeitos com amputação de membro inferior.

Walking speed and peak plantar pressure distribution during barefoot walking in persons with diabetes

BACKGROUND

The impact of walking speed has not been evaluated as a feasible outcome measure associated with peak plantar pressure (PPP) distribution, which may result in tissue damage in persons with diabetic foot complications. The objective of this pilot study was to determine the walking speed and PPP distribution during barefoot walking in persons with diabetes. 

METHODS

 Nine individuals with diabetes and nine age-gender matched individuals without diabetes participated in this study. Each individual was marked at 10 anatomical landmarks for vibration and tactile pressure sensation tests to determine the severity of sensory deficits on the plantar surface of the dominant limb foot. A steady state walking speed, PPP, the fore and rear foot (F/R) PPP ratio and gait variables were measured during barefoot walking. 

RESULTS

 Persons with diabetes had a significantly slower walking speed than the age-gender matched group resulting in a significant reduction of PPP at the F/R foot during barefoot walking (p < 0.05). There was no significant difference in F/R foot PPP ratio in the diabetic group compared with the age-gender matched group during barefoot walking (p > 0.05). There was a significant difference between the diabetic and non-diabetic groups for cadence, step time, toe out angle and the anterior-posterior excursion (APE) for centre of force (p < 0.05). 

CONCLUSION

 Walking speed may be a potential indicator for persons with diabetes to identify PPP distribution during barefoot walking in a diabetic foot. However, the diabetic group demonstrated a more cautious walking pattern than the age-gender matched group by decreasing cadence, step length and APE, and increasing step time and toe in/out angle. People with diabetes may reduce the risk of foot ulcerations as long as they are able to prevent severe foot deformities such as callus, hammer toe or charcot foot.