Interventions improve gait regularity in patients with peripheral neuropathy while walking on an irregular surface under low light

Adding Light Touch While Walking in Older Adults: Biomechanical and Neuromotor Effects

Adding haptic input may improve balance control and help prevent falls in older adults. This study examined the effects of added haptic input via light touch on a railing while walking. Participants (N = 53, 75.9 ± 7.9 years) walked normally or in tandem (heel to toe) with and without haptic input. During normal walking, adding haptic input resulted in a more cautious and variable gait pattern, reduced variability of center of mass acceleration and margin of stability, and increased muscle activity. During tandem walking, haptic input had minimal effect on step parameters, decreased lower limb muscle activity, and increased cocontraction at the ankle closest to the railing. Age was correlated with step width variability, stride length variability, stride velocity, variability of medial-lateral center of mass acceleration, and margin of stability for tandem walking. This complex picture of sensorimotor integration in older adults warrants further exploration into added haptic input during walking.

Falls and Cancer

Falls among older people are common and are associated with substantial morbidity, mortality and healthcare costs. Increasingly cancer is becoming a disease of older people and fall rates are higher in elders living with cancer. Cancer and its treatments potentiate important risk factors for falls, including muscle weakness, poor balance, proprioception, cognitive impairment and functional disability. Sarcopenia refers to the progressive deterioration in muscle strength, mass and quality with ageing. Chronic conditions and cancer amplify this decline and are associated with a greater negative effect on function. Age-related impairments of lower limb neurological function are commonly exacerbated by neurotoxic chemotherapy, resulting in gait and balance deficits. Postural instability and falls erode confidence and result in a negative cycle of diminishing activity levels, further deconditioning and a higher risk of further falls. Cancer-related fatigue, sleep and mood disturbances compound this progressive frailty, further worsening treatment tolerance and outcomes. Cognitive impairment is a potent risk factor for falling and is frequently associated with gait abnormalities. The well-recognised effects of cancer treatment on working memory, attention, processing speed and executive function are often apparent (when their presence is sought) before treatment and may be as much the result of the cancer itself as they are 'chemo brain'. Structured exercise programmes focusing on progressively challenging strength and balance training are of proven benefit in falls prevention. Regular aerobic exercise accrues additional benefits in improved cardiorespiratory resilience and concomitant positive effects on treatment tolerance. Increased activity levels positively influence cognition, mood and foster an improved sense of well-being. Simple, practicable clinic-based tests of physical functioning, cognition and neurological function can help to identify those at high risk of falls and functional decline. The use of such instruments can aid judicious treatment planning and identify those most likely to benefit from more detailed specialist comprehensive geriatric assessment.

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.

The Effect of Daily Use of Plantar Mechanical Stimulation Through Micro-Mobile Foot Compression Device Installed in Shoe Insoles on Vibration Perception, Gait, and Balance in People With Diabetic Peripheral Neuropathy

OBJECTIVE

People with diabetic peripheral neuropathy (DPN) have impaired gait and balance performance. The aim of this study is to investigate therapeutic effectiveness of mechanical stimulation through a wearable foot compression device equipped in a shoe insole on vibration perception, balance control and gait performance in people with DPN.

METHODS

Using a single-arm 4-week intervention study design, we examined effectiveness of daily use of shoes equipped with the foot compression device (Footbeat™, AVEX, Grand Junction, CO, USA) on improving vibration perception threshold (VPT_max), skin perfusion pressure (SPP), ankle brachial index (ABI), lower extremities edema (circumferences in the calf and ankle), and motor performance (postural sway with eyes open and closed conditions, and gait performance during normal, dual-task and fast walking). Thirty people with type 2 diabetes and symptoms of PN completed the experimental protocol.

RESULTS

Improvements in VPT_max (before = 27.4 V, after = 23.3 V, P = .007, d = 0.33, where d denotes effect size), center-of-mass sway in the mediolateral direction with both eyes open and closed conditions (before = 0.94 cm, after = 0.76 cm, P = .020, d = 0.47; before = 1.10 cm, after = 0.83 cm, P = .033, d = 0.66, respectively), and stride velocity for normal walking, dual-task walking and fast walking tasks (before = 0.87 m/s, after = 0.96 m/s, P = .017, d = 0.41; before = 0.75 m/s, after = 0.91 m/s, P = .001, d = 0.77; before = 1.10 m/s, after = 1.20 m/s, P = .043, d = 0.33, respectively) were found post treatment. There was no significant improvement in SPP, ABI, and circumferences in the calf and ankle.

CONCLUSIONS

Our findings suggest the wearable foot compression device may be effective for reducing neuropathic symptoms and enhancing motor performances in people with DPN.

Which Gait Parameters and Walking Patterns Show the Significant Differences Between Parkinson's Disease and Healthy Participants?

This study investigated the difference in the gait of patients with Parkinson’s disease (PD), age-matched controls and young controls during three walking patterns. Experiments were conducted with 24 PD, 24 age-matched controls and 24 young controls, and four gait intervals were measured using inertial measurement units (IMU). Group differences between the mean and variance of the gait parameters (stride interval, stance interval, swing interval and double support interval) for the three groups were calculated and statistical significance was tested. The results showed that the variance in each of the four gait parameters of PD patients was significantly higher compared with the controls, irrespective of the three walking patterns. This study showed that the variance of any of the gait interval parameters obtained using IMU during any of the walking patterns could be used to differentiate between the gait of PD and control people.

Design and Validation of an Instrumented Uneven Terrain Treadmill

Studying human and animal locomotion on an uneven terrain can be beneficial to basic science and applied studies for clinical and robotic applications. Traditional biomechanical analysis of human locomotion has often been limited to laboratory environments with flat, smooth runways and treadmills. The authors modified a regular exercise treadmill by attaching wooden blocks to the treadmill belt to yield an uneven locomotion surface. To ensure that these treadmill modifications facilitated biomechanical measurements, the authors compared ground reaction force data collected while a subject ran on the modified instrumented treadmill with a smooth surface with data collected using a conventional instrumented treadmill. Comparisons showed only minor differences. These results suggest that adding an uneven surface to a modified treadmill is a viable option for studying human or animal locomotion on an uneven terrain. Other types of surfaces (eg, compliant blocks) could be affixed in a similar manner for studies on other types of locomotion surfaces.

The effects of haptic input on biomechanical and neurophysiological parameters of walking: A scoping review

Walking is an important component of daily life requiring sensorimotor integration to be successful. Adding haptic input via light touch or anchors has been shown to improve standing balance; however, the effect of adding haptic input on walking is not clear. This scoping review systematically summarizes the current evidence regarding the addition of haptic input on walking in adults. Following an established protocol, relevant studies were identified using indexed data bases (Medline, EMBASE, PsychINFO, Google Scholar) and hand searches of published review articles on related topics. 644 references were identified and screened by a minimum of two independent researchers before data was extracted from 17 studies. A modified TREND tool was used to assess quality of the references which showed that the majority of studies were of moderate or high quality. Results show that adding haptic input changes walking behaviour. In particular, there is an immediate reduction in variability of gait step parameters and whole body stability, as well as a decrease in lower limb muscle activity. The effect of added haptic input on reflex modulation may depend on the limb of interest (i.e., upper or lower limb). Many studies did not clearly describe the amount and/or direction of haptic input applied. This information is needed to replicate and/or advance their results. More investigations into the use and design of the haptic tools, the attentional demands of adding haptic input, and clarity on short-term effects are needed. In addition, more is research needed to determine whether adding haptic input has significant, lasting benefits that may translate to fall prevention efforts.

Effects of foot and ankle devices on balance, gait and falls in adults with sensory perception loss: a systematic review

BACKGROUND

Foot and ankle devices are being developed as a method of preventing people with sensory perception loss sustaining a fall. Such devices are believed to work by reducing the likelihood of a fall by improving the balance and gait of the user.

OBJECTIVES

The objective of the review was to evaluate the effectiveness of foot and ankle devices for the prevention of falls and the improvement of balance and gait in adults with sensory perception loss.

INCLUSION CRITERIA TYPES OF PARTICIPANTS

Participants were community-dwelling adults with bilateral pathological sensory perception loss.

TYPES OF INTERVENTION(S)/PHENOMENA OF INTEREST

The current review evaluated any foot or ankle device, including but not restricted to, all types of footwear (therapeutic and retail), insoles (customized and prefabricated) and ankle-foot orthoses (AFOs).

TYPES OF STUDIES

In the absence of randomized controlled trials (RCT), the review considered experimental and epidemiological study designs, except case series, individual case reports and descriptive cross-sectional studies.

OUTCOMES

The primary outcome was number of falls. Secondary outcome measures were clinical or laboratory measures of balance or gait.

SEARCH STRATEGY

A search for published and unpublished literature from inception to March 2015 written in the English language was conducted across a number of major electronic databases. A three-step search strategy was developed using MeSH terminology and keywords to ensure all that relevant materials are captured.

METHODOLOGICAL QUALITY

Methodological quality of included studies was assessed by two reviewers, who appraised each study independently, using standardized Joanna Briggs Institute (JBI) critical appraisal tools.

DATA EXTRACTION

Quantitative data were extracted from the studies that were identified as meeting the criteria for methodological quality using the standardized JBI data extraction tools.

DATA SYNTHESIS

Due to the heterogeneity of populations, interventions and outcome measures, meta-analyses were not possible and results are presented in narrative form.

RESULTS

Nine trials (from 10 papers) involving 238 participants, (14 with multiple sclerosis and 16 with idiopathic peripheral neuropathy, 150 with diabetic neuropathy) and 58 controls were included in the review. No study reported falls as an outcome measure. The results of the included studies found that in people with sensory perception loss, postural sway improved with vibrating insoles and AFO, altering the softness and texture of the top cover had no effect on postural sway, wearing footwear over long distances or AFOs improved step-to-step consistency, and no foot and ankle device was reported to have a negative effect on the balance or gait of people with sensory perception loss. The methodological quality of the included studies was poor. No study used a randomized controlled trial (RCT) methodology. No study incorporated a follow-up period or tested the intervention within the context of the intended clinical environment.

CONCLUSION

There is limited evidence to suggest that footwear and insole devices can artificially alter postural stability and may reduce the step-to-step variability in adults with sensory perception loss. Varying the material properties of an insole does not notably affect static balance or gait.

An immediate effect of custom-made ankle foot orthoses on postural stability in older adults

BACKGROUND

Foot and ankle problems are highly prevalent fall risks in the elderly. Ankle foot orthoses designed to stabilize the foot and ankles have been studied within specific patient groups, but their efficacy with a less restrictive elderly population is unknown. This study investigated if custom-made ankle foot orthoses improve postural stability in older adults.

METHODS

Thirty ambulatory older adults averaged 73 (standard deviation=6.5) years completed Romberg's balance (eyes-open/eyes-closed), functional reach, and Timed Up and Go tests while wearing validated kinematic sensors. Each test was completed in standardized shoes with and without bilateral orthoses. Additionally, barefoot trials were conducted for the Romberg's and functional reach tests.

FINDINGS

Compared to the barefoot and 'shoes alone' conditions, the orthoses reduced center of mass sway on average by 49.0% (P=0.087) and 40.7% (P=0.005) during eyes-open balance trials. The reduction was amplified during the eyes-closed trials with average reductions of 65.9% (P=0.000) and 47.8% (P=0.004), compared to barefoot and 'shoes alone' conditions. The orthoses did not limit functional reach distance nor timed-up and go completion times. However, the medial-lateral postural coordination while reaching was improved significantly with orthoses compared to barefoot (14.3%; P=0.030) and 'shoes alone' (13.5%; P=0.039) conditions.

INTERPRETATION

Ankle foot orthoses reduced postural sway and improved lower extremity coordination in the elderly participants without limiting their ability to perform a standard activity of daily living. Additional studies are required to determine if these benefits are retained and subsequently translate into fewer falls.

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.

Hip strength: ankle proprioceptive threshold ratio predicts falls and injury in diabetic neuropathy

INTRODUCTION

We determined lower limb neuromuscular capacities associated with falls and fall-related injuries in older people with declining peripheral nerve function.

METHODS

Thirty-two subjects (67.4 ± 13.4 years; 19 with type 2 diabetes), representing a spectrum of peripheral neurologic function, were evaluated with frontal plane proprioceptive thresholds at the ankle, frontal plane motor function at the ankle and hip, and prospective follow-up for 1 year.

RESULTS

Falls and fall-related injuries were reported by 20 (62.5%) and 14 (43.8%) subjects, respectively. The ratio of hip adductor rate of torque development to ankle proprioceptive threshold (Hip(STR) /AnkPRO ) predicted falls (pseudo-R(2)  = .726) and injury (pseudo-R(2)  = .382). No other variable maintained significance in the presence of Hip(STR) /AnkPRO .

CONCLUSIONS

Fall and injury risk in the population studied is related inversely to Hip(STR) /AnkPRO . Increasing rapidly available hip strength in patients with neuropathic ankle sensory impairment may decrease risk of falls and related injuries.

Effect of age on the ability to recover from a single unexpected underfoot perturbation during gait: kinematic responses

A sudden underfoot perturbation can present a serious threat to balance during gait, but little is known about how humans recover from such perturbations or whether their response is affected by age. We tested the hypothesis that age would not affect the stepping responses to a nominal 10 degree inversion or eversion of the stance foot during gait. Twenty-three healthy young (22.7±3.35 yrs) and 18 healthy old adults (68.0±7.19 yrs) performed 60 walking trials along a 6-m level walkway at a normal gait speed. In 16 of these trials, a single medial (MP) or lateral (LP) perturbation was randomly administered once under the left or right foot. Recovery step width (SW), step length (SL), trunk kinematics and walking speed were measured optoelectronically. Repeated-measures analysis of variance and post hoc t-tests were used to test the hypotheses. The results show that a MP or LP altered the recovery SL (p=0.005) and age affected the number of recovery steps (p=0.017), as well as the first recovery SW and SL (p=0.013 and p=0.031, respectively). Both MP and LP caused young adults to have wider SW (p<0.02) and shorter SL (p<0.005) without changing trunk movement during their first recovery step. Older adults, however, significantly changed lateral trunk inclination during the first recovery step, decreased their fourth recovery SL (p<0.001). We conclude that young adults adjust the step kinematics of as many as four recovery steps following this perturbation, a response that was delayed and significantly weaker in older adults who instead exhibited an immediate torso inclination consistent with a hip response strategy.

Gradual training reduces the challenge to lateral balance control during practice and subsequent performance of a novel locomotor task

Locomotor balance control mechanisms and impairments have been well described in the literature. In contrast, the role of evidence-based motor learning strategies in the recovery or restoration of locomotor balance control has received much less attention. Little is known about the efficacy of motor learning strategies to improve locomotor tasks and their unique requirements, such as lateral balance control. This study examined whether gradual versus sudden training influenced lateral balance control among unimpaired adults (n=16) during training and 24-h transfer performance of a novel locomotor task. This was accomplished by examining the variability of whole-body frontal plane kinematics throughout training and 24-h transfer performance of asymmetric split-belt treadmill walking. Compared to sudden training, gradual training significantly reduced the challenge to lateral balance control (exhibited by a reduction in frontal plane kinematic variability) during training and during subsequent transfer task performance. These results indicate that gradual training could play an important role in restoring locomotor balance control during physical rehabilitation.

Regulation of whole-body frontal plane balance varies within a step during unperturbed walking

This study sought to determine whether the need to actively control lateral balance is consistent within a step. Variability of the frontal plane COM-Ankle angle was calculated over 50 strides at discrete gait events for twenty-one healthy young adults to quantify active control of lateral balance within a step. Frontal plane COM-Ankle angle variability was found to vary significantly between all gait events, decreasing progressively within a step. This suggests that active control of lateral balance varies significantly within a step and that the greatest degree of active control occurs at heel-strike. The increased active control of lateral balance during heel-strike indicates a degree of preparation to ensure sufficient lateral balance control prior to more challenging events. These results provide insight into the mechanisms of lateral balance control and how to assess and treat locomotor balance control impairments.

Frontal plane hip and ankle sensorimotor function, not age, predicts unipedal stance time

INTRODUCTION

Changes occur in muscles and nerves with aging. In this study we explore the relationship between unipedal stance time (UST) and frontal plane hip and ankle sensorimotor function in subjects with diabetic neuropathy.

METHODS

UST, quantitative measures of frontal plane ankle proprioceptive thresholds, and ankle and hip motor function were tested in 41 subjects with a spectrum of lower limb sensorimotor function ranging from healthy to moderately severe diabetic neuropathy.

RESULTS

Frontal plane hip and ankle sensorimotor function demonstrated significant relationships with UST. Multivariate analysis identified only composite hip strength, ankle proprioceptive threshold, and age to be significant predictors of UST (R(2) = 0.73), explaining 46%, 24%, and 3% of the variance, respectively.

CONCLUSIONS

Frontal plane hip strength was the single best predictor of UST and appeared to compensate for less precise ankle proprioceptive thresholds. This finding is clinically relevant given the possibility of strengthening the hip, even in patients with significant peripheral neuropathy.

An exercise intervention to improve diabetic patients' gait in a real-life environment

AIMS

Gait characteristics and balance are altered in diabetic individuals. Little is known about possible treatment strategies. This study evaluated the effect of a specific training program on diabetic patients' gait.

METHODS

A randomized controlled trial (N=71) with an intervention (IG) (N=35), and control group (CG) (N=36). The intervention consisted of physiotherapeutic group training including gait and balance exercises with function-oriented strengthening. Controls received no treatment.

RESULTS

After intervention the IG increased their habitual walking speed by 0.149ms(-1) (0.54kmh(-1)) on tarred terrain and by 0.169ms(-1) (0.61kmh(-1)) on the cobblestones. This significant treatment effect (p<0.001) decreased slightly at the six-month follow-up, but remained significant (p<0.001). In a similar manner, significant improvement was observed for cadence, gait cycle time and stance time on both terrains. All outcomes except stance time on the tarred terrain remained significant at the six-month follow-up. No significant effect was observed for stride length and the coefficient of variation of gait cycle time (on either surface) at the corrected significance level of p<0.004. CG patients' parameters all remained unchanged or progressively deteriorated compared to baseline values.

DISCUSSION

Cadence contributed 80%, whereas stride length only contributed 20% to the change of gait velocity. This may be due to the treatment or to diabetic patients' potential to regulate their cadence and stride length.

CONCLUSION

A specific training program can improve diabetic patients' gait in a real life environment. A challenging environment highlights treatment effects on patients' gait better than an evenly tarred surface.

Do ankle orthoses improve ankle proprioceptive thresholds or unipedal balance in older persons with peripheral neuropathy?

OBJECTIVE

To determine whether ankle orthoses that provide medial and lateral support, and have been found to decrease gait variability in older persons with peripheral neuropathy, decrease (improve) frontal plane ankle proprioceptive thresholds or increase unipedal stance time in that same population.

DESIGN

Observational study in which unipedal stance time was determined with a stopwatch, and frontal plane ankle (inversion and eversion) proprioceptive thresholds were quantified during bipedal stance using a foot cradle system and a series of 100 rotational stimuli, in 11 older neuropathic subjects (8 men; age 72 +/- 7.1 yr) with and without ankle orthoses.

RESULTS

The subjects demonstrated no change in combined frontal plane (inversion + eversion) proprioceptive thresholds or unipedal stance time with vs. without the orthoses (1.06 +/- 0.56 vs. 1.13 +/- 0.39 degrees, respectively; P = 0.955 and 6.1 +/- 6.5 vs. 6.2 +/- 5.4 secs, respectively; P = 0.922).

CONCLUSION

Ankle orthoses that provide medial-lateral support do not seem to change ankle inversion/eversion proprioceptive thresholds or unipedal stance time in older persons with diabetic peripheral neuropathy. Previously identified improvements in gait variability using orthoses in this population are therefore likely related to an orthotically induced stiffening of the ankle rather than a change in ankle afferent function.

The gait and balance of patients with diabetes can be improved: a randomised controlled trial

AIMS/HYPOTHESIS

Gait characteristics and balance are altered in diabetic patients. Little is known about possible treatment strategies. This study evaluates the effect of a specific training programme on gait and balance of diabetic patients.

METHODS

This was a randomised controlled trial (n=71) with an intervention (n=35) and control group (n=36). The intervention consisted of physiotherapeutic group training including gait and balance exercises with function-orientated strengthening (twice weekly over 12 weeks). Controls received no treatment. Individuals were allocated to the groups in a central office. Gait, balance, fear of falls, muscle strength and joint mobility were measured at baseline, after intervention and at 6-month follow-up.

RESULTS

The trial is closed to recruitment and follow-up. After training, the intervention group increased habitual walking speed by 0.149 m/s (p<0.001) compared with the control group. Patients in the intervention group also significantly improved their balance (time to walk over a beam, balance index recorded on Biodex balance system), their performance-oriented mobility, their degree of concern about falling, their hip and ankle plantar flexor strength, and their hip flexion mobility compared with the control group. After 6 months, all these variables remained significant except for the Biodex sway index and ankle plantar flexor strength. Two patients developed pain in their Achilles tendon: the progression for two related exercises was slowed down.

CONCLUSIONS/INTERPRETATION

Specific training can improve gait speed, balance, muscle strength and joint mobility in diabetic patients. Further studies are needed to explore the influence of these improvements on the number of reported falls, patients' physical activity levels and quality of life.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00637546

FUNDING

This work was supported by the Swiss National Foundation (SNF): PBSKP-123446/1/

Gait alterations of diabetic patients while walking on different surfaces

Patients with diabetes have been shown to suffer from increased fall risk. However, authors disagree as to whether only diabetic patients with neuropathy, or also those without neuropathy, present gait alterations. Existing studies evaluate gait indoors, i.e. in specialized gait laboratories. This study evaluates gait parameters in diabetic patients under various real life conditions and compares them to those recorded for healthy controls.

METHODS

We conducted a clinical observation study. Forty-five subjects' gait was assessed on three different surfaces (tar, grass and stones) with a Physilog system (BioAGM, CH), consisting of accelerometers and gyroscopes. Temporal and spatial gait parameters as well as stride-to-stride variability of 30 patients with type 2 diabetes, 15 with and 15 without neuropathy were compared to 15 healthy controls. The three groups were comparable for age, height and body weight (p>0.05).

RESULTS

Diabetic patients' gait parameters differed significantly from those of healthy controls. Post hoc analysis revealed a significant difference between healthy individuals and patients with neuropathy, and between healthy individuals and patients without neuropathy. No difference was observed between patients with and without neuropathy. The highest surface effect was found in patients with diabetic neuropathy, followed by patients without neuropathy and healthy controls.

CONCLUSIONS

Walking in real life conditions revealed gait difficulties in patients with type 2 diabetes before neuropathy was clinically detectable. Clinicians should be aware that diabetic individuals' gait capacity decreases and fall risk increases at an early stage of the disease.

Reliability of diabetic patients' gait parameters in a challenging environment

Activities of daily life require us to move about in challenging environments and to walk on varied surfaces. Irregular terrain has been shown to influence gait parameters, especially in a population at risk for falling. A precise portable measurement system would permit objective gait analysis under such conditions. The aims of this study are to (a) investigate the reliability of gait parameters measured with the Physilog in diabetic patients walking on different surfaces (tar, grass, and stones); (b) identify the measurement error (precision); (c) identify the minimal clinical detectable change.

METHODS

16 patients with Type 2 diabetes were measured twice within 8 days. After clinical examination patients walked, equipped with a Physilog, on the three aforementioned surfaces.

RESULTS

ICC for each surface was excellent for within-visit analyses (>0.938). Inter-visit ICC's (0.753) were excellent except for the knee range parameter (>0.503). The coefficient of variation (CV) was lower than 5% for most of the parameters. Bland and Altman Plots, SEM and SDC showed precise values, distributed around zero for all surfaces.

DISCUSSION

Good reliability of Physilog measurements on different surfaces suggests that Physilog could facilitate the study of diabetic patients' gait in conditions close to real-life situations. Gait parameters during complex locomotor activities (e.g. stair-climbing, curbs, slopes) have not yet been extensively investigated.

CONCLUSION

Good reliability, small measurement error and values of minimal clinical detectable change recommend the utilization of Physilog for the evaluation of gait parameters in diabetic patients.

Gait characteristics of diabetic patients: a systematic review

Patients with diabetes are at higher risk of experiencing fall-related injuries when walking than healthy controls. The underlying mechanism responsible for this is not yet clear. Thus we intend to summarize diabetic patients' gait characteristics and emphasize those which could be the possible underlying mechanisms for increased fall risk. This systematic review aims, in particular, to: (1) evaluate the quality of existing studies which investigate the gait characteristics of diabetic patients, (2) highlight areas of agreement and contradiction in study results, (3) discuss and emphasize parameters associated with fall risk, and (4) propose new orientations and further domains for research needed for their fall risk prevention. We conducted an electronic search of Pedro, PubMed, Ovid and Cochrane. Two authors independently assessed all abstracts. Quality of the selected articles was scored, and the study results summarized and discussed. We considered 236 abstracts of which 28 entered our full text review. Agreement on data quality between two reviewers was high (kappa: 0.90). Authors investigating gait parameters in a diabetic population evaluated in particular parameters either associated with fall risk (speed, step length or step-time variability) or with ulcers (pressure). There is agreement that diabetic patients walk slower, with greater step variability, and present higher plantar pressure than healthy controls. We concluded that diabetic patients present gait abnormalities, some of which can lead to heightened fall risk. To understand its' underlying mechanisms, and to promote efficient prevention, further studies should analyse gait under 'real-life' conditions.

An exploration of step time variability on smooth and irregular surfaces in older persons with neuropathy

BACKGROUND

Increased step time variability, particularly on an irregular surface, has been associated with impaired mobility function and a variety of diseases. However the biomechanical necessity, or advantage, of increasing step time variability has not been identified.

METHODS

We performed a secondary analysis of gait data previously obtained on 42 subjects age 50 or older with neuropathy who walked on smooth and irregular surfaces, the latter with and without three interventions (cane, ankle orthosis and wall touch) that provided frontal plane support.

FINDINGS

Step time variability on smooth and irregular surfaces was most strongly associated with reduction in step length on the irregular surface as compared to the smooth. More specifically, the greater the decrease in step length on the irregular surface the greater the step time variability on both surfaces and the greater the increase in step time variability on the irregular surface. The increase in step length on the irregular surface afforded by the interventions coincided with a decrease in step time variability. The subjects did not simultaneously demonstrate increased step time variability and step width range on the irregular surface.

INTERPRETATION

Among adults age 50 and older with neuropathy, increased step time variability is strongly associated with the need to shorten step length on an irregular surface. Therefore step time variability may be a marker for instability during single limb stance which necessitates rapidly placed, shortened recovery steps. Such steps may also offer the advantage of reducing extremes in lateral foot placement of the swing limb, and so assist in maintaining frontal plane stability.

Putting evidence into practice: evidence-based interventions for chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) continues to be a significant, debilitating symptom resulting from the administration of neurotoxic chemotherapy for the treatment of cancer. CIPN is an important consequence of cancer treatment because of its potential impact on physical functioning and quality of life. Oncology nurses play an important role in assessing, monitoring, and educating clients about CIPN. Despite investigations concerning pharmacologic and nonpharmacologic approaches to either preventing or minimizing the neurotoxicity resulting from certain chemotherapeutic agents, evidence to support the interventions is lacking. This article presents information concerning CIPN and summarizes the evidence for pharmacologic and nonpharmacologic approaches to the prevention and treatment of CIPN.

What causes a crossover step when walking on uneven ground? A study in healthy young women

We hypothesized that, during gait, the perturbation caused by stepping on a 1.2-cm high protuberance with the medial forefoot would not only alter stance foot kinematics and kinetics, but also alter subsequent step location and timing, even to the point of causing a crossover step. Twelve healthy young women performed at least three flat surface and three perturbation trials while walking along a level walkway. To obstruct visual monitoring of their upcoming foot placement they used both hands to carry a large tray in front of their abdomen. Kinematic data from optoelectronic markers and force plate data were recorded at 50 and 100Hz, respectively. The results showed that the medial forefoot perturbation significantly decreased the net ankle eversion moment (p<0.001) and increased the maximum inversional foot acceleration (p=0.007). Step width (SW) and time (ST) of the post-perturbation recovery step were significantly decreased compared with normal steps (p=0.002 and 0.049, respectively). The maximum inversional foot acceleration correlated negatively with SW and ST of the recovery step (both p=0.001). Finally, four of 36 (12%) recovery steps were crossover steps. We conclude that a medial forefoot perturbation results in an increased inversional acceleration of the stance foot followed by a decrease in recovery SW and ST. In some cases, a medial forefoot perturbation can result in a crossover step, an extreme form of a narrow recovery step.

Laboratory-free measurement of gait rhythmicity in the assessment of the degree of impairment and the effectiveness of rehabilitation in patients with vertigo resulting from vestibular hypofunction

A portable system for measurement of stride time rhythmicity was developed using the technique of Hausdorff et al (2001a Arch. Phys. Med. Rehabil. 82 1050-6). Measurement was performed for an extended period of walking of 256 steps for each foot outside of the laboratory on 18 normal individuals and 20 patients referred with symptomatic vestibular impairment. Ten of the patients were reassessed following vestibular therapy. Gait rhythmicity measured by standard deviation (SD) stride time was found to be significantly higher in patients with vestibular impairment than in normal volunteers (mean +/- SD 60.3 +/- 39.8 ms versus 21.9 +/- 4.9 ms respectively, P < 0.001, t-test). The ten patients who returned following a course of vestibular rehabilitation displayed significant improvement in SD stride time following therapy (mean +/- SD 57.3 +/- 44.6 ms prior to and 40.9 +/- 23 ms following therapy, P = 0.01, Wilcoxon signed rank test). Gait rhythmicity measurement, specifically measurement of stride time variability, appears to be a powerful assessment tool for objective measurement of extent of impairment and response to therapy in patients with vestibular hypofunction.

Falls and Gait Characteristics Among Older Persons with Peripheral Neuropathy

OBJECTIVE

To prospectively determine the frequency and circumstances of falls in older persons with peripheral neuropathy and to identify gait characteristics on smooth and irregular surfaces associated with falls in this same population.

DESIGN

This was a descriptive and observational study of a prospective group cohort. Spatial and temporal gait measures on smooth and irregular surfaces, as well as basic demographic and clinical data, were obtained in 20 older persons with peripheral neuropathy. Falls and fall-related injuries were then prospectively determined for 1 yr.

RESULTS

Thirteen of 20 (65%) subjects fell, and 6 of 20 (30%) subjects sustained a fall-related injury during the year of observation. Of the 76 reported falls, 69 (90.8%) were associated with a surface abnormality (irregular or slick). Gait measures on the smooth surface did not distinguish between fall groups. On the irregular surface, however, step-time variability tended to be higher for those subjects who fell than for those who did not (89 +/- 29 vs. 64 +/- 26 msecs, respectively; P = 0.077) and for those who were injured from a fall compared with those who were not injured (101 +/- 21 vs. 71 +/- 29 msecs, respectively; P = 0.038).

CONCLUSIONS

Older patients with peripheral neuropathy have a high rate of falls, and these falls are often associated with walking on irregular surfaces. Gait analysis on an irregular surface may be superior to that on a smooth surface for detecting fall risk in this patient population.

Automatic postural responses in individuals with peripheral neuropathy and ankle-foot orthoses

Eleven individuals with sensory neuropathy participated in static and dynamic balance tests with and without ankle-foot orthoses (AFOs). During the tests the subjects were required to stand on a fixed or moving computer-controlled platform with their eyes open or closed. Equilibrium scores, response latency, and strength scores were obtained. For all tests equilibrium scores were significantly larger in experiments with AFOs in comparison to conditions without AFOs (P<0.01). Decreased latency of responses with AFOs were recorded for medium and large magnitudes of movements of the platform in forward and backward directions. In addition, increased strength scores were observed when AFOs were used. The results indicate that AFOs could contribute significantly to postural control in individuals with peripheral neuropathy by providing auxiliary sensory cues to intact tissues of the lower extremities. These results have clinical implications that primarily aid in the understanding of how individuals with peripheral neuropathy benefit from the use of AFOs for postural stability.

A tactile stimulus applied to the leg improves postural stability in young, old and neuropathic subjects

The purpose of this study was to determine whether the application of passive tactile cues to the lower limb could improve postural stability in healthy young controls, older people and people with diabetic peripheral neuropathy. Antero-posterior sway was measured with eyes open and closed in 10 healthy young subjects (mean age 27 years, 5 male, 5 female), 10 older subjects without diabetic peripheral neuropathy (mean age 88 years, 2 male, 8 female) and 10 subjects with diabetic peripheral neuropathy (mean age 65 years, 6 male, 4 female) while a small piece of Velcro attached to a flexible mount was applied to three different sites on the leg (ankle, calf, and knee). Across all conditions, the mean sway of the neuropathic subjects was 93% greater than for the young subjects and 11% more than the older subjects. On average, subjects swayed 10% more with the eyes closed than with the eyes open. Each stimulus reduced sway, but the effect increased approximately in proportion to the height of the stimulus above the ankles (ankle 7.6%, calf 13.5%, knee 20.1% reduction compared to the no stimulus condition). This experiment demonstrates that a passive stimulus applied to the skin of the leg, which provides sensory information about body movement, significantly reduces body sway during standing. This applies to older subjects and subjects with peripheral neuropathy as well as healthy young subjects. These results have implications for novel approaches for improving stability in people with peripheral sensory loss.

Attention demanding tasks during treadmill walking reduce step width variability in young adults

Background

The variability of step time and step width is associated with falls by older adults. Further, step time is significantly influenced when performing attention demanding tasks while walking. Without exception, step time variability has been reported to increase in normal and pathologically aging older adults. Because of the role of step width in managing frontal plane dynamic stability, documenting the influence of attention-demanding tasks on step width variability may provide insight to events that can disturb dynamic stability during locomotion and increase fall risk. Preliminary evidence suggests performance of an attention demanding task significantly decreases step width variability of young adults walking on a treadmill. The purpose of the present study was to confirm or refute this finding by characterizing the extent and direction of the effects of a widely used attention demanding task (Stroop test) on the step width variability of young adults walking on a motorized treadmill.

Methods

Fifteen healthy young adults walked on a motorized treadmill at a self-selected velocity for 10 minutes under two conditions; without performing an attention demanding task and while performing the Stroop test. Step width of continuous and consecutive steps during the collection was derived from the data recorded using a motion capture system. Step width variability was computed as the standard deviation of all recorded steps.

Results

Step width decreased four percent during performance of the Stroop test but the effect was not significant (p = 0.10). In contrast, the 16 percent decrease in step width variability during the Stroop test condition was significant (p = 0.029).

Conclusion

The results support those of our previous work in which a different attention demanding task also decreased step width variability of young subjects while walking on a treadmill. The decreased step width variability observed while performing an attention demanding task during treadmill walking may reflect a voluntary gait adaptation toward a more conservative gait pattern emphasizing frontal plane control of the trunk. Extension of the experimental paradigm to older adults and mechanistic approaches to link step width variability to dynamic stability, and falls, in a cause-effect manner are necessary.

Effects of surface irregularity and lighting on step variability during gait: a study in healthy young and older women

Relatively few studies have examined how uneven surfaces affect human gait. To study this, along with the effects of advancing age and low light conditions, we measured step width and step time variability, as well as comfortable gait speed, in 12 healthy young women (YW) and 12 healthy older women (OW) as they walked at a comfortable speed along a 10-m walkway. Ten trials were completed for each cell of a 2 x 2 factorial design: (1) flat surface with regular lighting; (2) flat surface with low lighting; (3) irregular surface with regular lighting; and (4) irregular surface with low lighting. Effects of surface type, incident lighting, and age on gait parameters were tested via repeated measures ANOVA. Surface type significantly affected step width variability (P < 0.001) and step time variability (P < 0.001). Light level showed no significant effect on any of the gait parameters. One significant age group difference was found: step width variability was significantly greater in OW than YW (P = 0.010). We conclude that the irregular surface had a greater effect on the gait variability of healthy OW than on that of healthy YW.

Influence of an irregular surface and low light on the step variability of patients with peripheral neuropathy during level gait

Patients with peripheral neuropathy (PN) report greater difficulty walking on irregular surfaces with low light (IL) than on flat surfaces with regular lighting (FR). We tested the primary hypothesis that older PN patients would demonstrate greater step width and step width variability under IL conditions than under FR conditions. Forty-two subjects (22 male, 20 female: mean +/- S.D.: 64.7 +/- 9.8 years) with PN underwent history, physical examination, and electrodiagnostic testing. Subjects were asked to walk 10 m at a comfortable speed while kinematic and force data were measured at 100 Hz using optoelectronic markers and foot switches. Ten trials were conducted under both IL and FR conditions. Step width, time, length, and speed were calculated with a MATLAB algorithm, with the standard deviation serving as the measure of variability. The results showed that under IL, as compared to FR, conditions subjects demonstrated greater step width (197.1 +/- 40.8 mm versus 180.5 +/- 32.4 mm; P < 0.001) and step width variability (40.4 +/- 9.0 mm versus 34.5 +/- 8.4 mm; P < 0.001), step time and its variability (P < 0.001 and P = 0.003, respectively), and step length variability (P < 0.001). Average step length and gait speed decreased under IL conditions (P < 0.001 for both). Step width variability and step time variability correlated best under IL conditions with a clinical measure of PN severity and fall history, respectively. We conclude that IL conditions cause PN patients to increase the variability of their step width and other gait parameters.

Managing variability in the summary and comparison of gait data

Variability in quantitative gait data arises from many potential sources, including natural temporal dynamics of neuromotor control, pathologies of the neurological or musculoskeletal systems, the effects of aging, as well as variations in the external environment, assistive devices, instrumentation or data collection methodologies. In light of this variability, unidimensional, cycle-based gait variables such as stride period should be viewed as random variables and prototypical single-cycle kinematic or kinetic curves ought to be considered as random functions of time. Within this framework, we exemplify some practical solutions to a number of commonly encountered analytical challenges in dealing with gait variability. On the topic of univariate gait variables, robust estimation is proposed as a means of coping with contaminated gait data, and the summary of non-normally distributed gait data is demonstrated by way of empirical examples. On the summary of gait curves, we discuss methods to manage undesirable phase variation and non-robust spread estimates. To overcome the limitations of conventional comparisons among curve landmarks or parameters, we propose as a viable alternative, the combination of curve registration, robust estimation, and formal statistical testing of curves as coherent units. On the basis of these discussions, we provide heuristic guidelines for the summary of gait variables and the comparison of gait curves.

A Comparison of Gait Characteristics Between Older Women with and Without Peripheral Neuropathy in Standard and Challenging Environments

OBJECTIVES

To compare gait patterns in older women with and without peripheral neuropathy (PN) in standard (smooth surface, normal lighting) and challenging environments (CE) (irregular surface, low lighting).

DESIGN

Observational, controlled study of 24 subjects.

SETTING

Biomechanical research laboratory.

PARTICIPANTS

Twenty-four older women, 12 with PN and 12 without PN (mean age +/- standard deviation =67.1 +/- 7.9 and 70.2 +/- 4.3, respectively).

MEASUREMENTS

Gait parameters and, in the 12 PN subjects, neuropathy severity.

RESULTS

The CE was associated with increases in step width, step-width variability, step-width range, step width-to-step length ratio, step time and step-time variability, and decreases in step length and speed. The PN subjects demonstrated a greater step width-to-step length ratio and step time and shorter step length and slower speed than the control subjects. In adapting to the CE, the PN subjects demonstrated greater increases in step width-to-step length ratio and step-time variability and a greater decrease in step length than did the control subjects. In the standard environment, only one gait parameter correlated with PN severity, whereas in the CE, four gait parameters did so.

CONCLUSION

The subjects demonstrated a gait that was slower, less efficient, and more variable temporally and in the frontal plane in the CE. Control and PN subjects demonstrated similar variability in medial-lateral step placement in the CE but at the cost of speed and efficiency for the PN subjects. Because the CE magnified gait differences between the two groups of subjects and caused gait changes in the PN subjects that correlated with PN severity, the CE may offer improved resolution for detecting gait abnormalities.