Improving Physical, Physiological, and Psychological Health Outcomes in Patients with Diabetic Foot Ulcers - State of the Art

Diabetic foot disease is a complex and challenging complication of diabetes mellitus, which imposes a significant burden of disease on patients, their carers, and the wider health systems. Recurrence rates are high, and current evidence indicates a high mortality associated with it. While management algorithms have primarily focused on the physical aspects of healing, there is increasing recognition of the critical role played by psychological and biomechanical factors in the development and resolution of diabetic foot disease. Therefore, in this paper, we aim to explore how diabetic foot outcomes can be improved by addressing not only the physical but also the psychological and biomechanical aspects that are integral to the development of this condition and its optimal resolution. We explore new technologies that allow for non-invasive objective assessment of the diabetic foot at risk, and we also explore the role of understanding biomechanics, which is essential to determining risk of foot disease, but also the potential for recurrence. In addition, we discuss the evidence linking depression and cognitive impairment to diabetic foot disease and offer our insight on the research direction required before implementing novel information into front-line clinics.

Effects of foot-ankle exercises on foot-ankle kinematics, plantar pressure, and gait kinetics in people with diabetic neuropathy: Secondary outcomes from a randomized controlled trial

BACKGROUND

Follow-up report of secondary outcomes of a randomized, single-blinded, parallel controlled trial that investigated the benefits of a foot-ankle therapeutic exercise program on foot-ankle kinematics, plantar pressure, and lower limb kinetics during gait in individuals with diabetic neuropathy (DPN).

METHODS

Sixty-six participants with DPN were randomly allocated into a control group (CG; n = 31), which received usual care, and an intervention group (IG; n = 35), which received usual care plus a 12-week group-based foot-ankle exercise program. Outcomes were assessed at baseline and 12 weeks by an assessor blinded to group allocation.

RESULTS

The generalized linear mixed model and intention-to-treat analysis revealed a greater hip extensor moment at push-off and greater hallux contact area in the IG than CG after 12 weeks. A within-group analysis revealed a larger arch height during stance and higher peak pressure and pressure-time integral at the central forefoot region in the IG after 12 weeks compared to baseline. There were no other significant group difference or changes over time in foot-ankle kinematics or in any other joint moment related to overall lower limb biomechanics.

CONCLUSION

The increases in hip moment at push-off and hallux surface contact area suggest an improvement in the propulsion phase with greater participation of the toes in foot rollover after 12 weeks of a group-based foot-ankle exercises program for people with DPN. Individual face-to-face, longer-term, and more intensive interventions may be needed to positively influence foot-ankle biomechanics and pressure parameters in other plantar areas.

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.

Gait Parameters and Peripheral Neuropathy in Patients With Diabetes: A Meta-Analysis

OBJECTIVE

To investigate the relationship between diabetic peripheral neuropathy (DPN) and gait abnormality in diabetic patients.

METHODS

Related research concerning the gait of diabetic patients with and without DPN was collected and analyzed by searching PubMed, Embase, and Web of Science. Statistical analysis was performed by using RevMan 5.3 software.

RESULTS

Twenty-one studies were included in this meta-analysis, consisting of 499 diabetic neuropathy patients and 467 diabetes controls without neuropathy. Meta-analysis results showed lower gait velocity, shorter stride length, longer stride time, longer stance time, and higher maximum knee extension moment in the DPN group, compared with their counterparts.

CONCLUSION

Among diabetic patients, those complicated with DPN possess lower gait velocity, shorter stride length, longer stride time, longer stance time, and higher maximum knee extension moment.

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.

Effect of an educational booklet for prevention and treatment of foot musculoskeletal dysfunctions in people with diabetic neuropathy: the FOotCAre (FOCA) trial II, a study protocol of a randomized controlled trial

Background

This study is a part of a series of two clinical trials. We consider diabetic polyneuropathy (DPN), a common chronic and progressive complication of diabetes mellitus that has several impacts on individuals’ foot health and quality of life. Based on the current trends of self-monitoring and self-care, providing a tool with foot-related exercises and educational care may help patients to avoid or reduce the musculoskeletal complications resulting from DPN, improving autonomous performance in daily living tasks. The aim of this trial is to evaluate the effects of an educational booklet for foot care and foot muscle strengthening on DPN symptoms and severity, clinical outcomes, and gait biomechanics in patients with DPN.

Methods/design

The FOotCAre (FOCA) trial II study has been designed as a single-blind, two-parallel-arm randomized controlled trial. It will include 48 patients with DPN who will be randomly allocated to a control (recommended foot care by international consensus with no foot exercises) group or an intervention (foot-related exercises using an educational booklet three times/week at home for 8 weeks) group. Participants from both groups will be assessed at baseline, after 8 weeks, and at 16 weeks for follow-up. The primary outcomes are the DPN symptoms and severity, and the secondary outcomes are foot–ankle kinematics, gait kinetics, plantar pressure distribution during gait, tactile and vibratory sensitivities, foot strength, functional balance, and foot health and functionality.

Discussion

The booklet is a management tool that allows users to be autonomous in their treatment by choosing how and where to perform the exercises. This allows the patients to perform the exercises regularly as a continuous habit for foot care and health, which is an important element in the management of the diabetic foot. As the booklet focuses on specific foot–ankle exercises, we expect that it will improve the clinical aspects of DPN and produce beneficial biomechanical changes during gait, becoming a powerful self-management tool that can be easily implemented to improve the performance of daily living tasks.

Trial registration

ClinicalTrials.gov, NCT04008745. Registered on 2 July 2019.

Study protocol for a randomized controlled trial on the effect of the Diabetic Foot Guidance System (SOPeD) for the prevention and treatment of foot musculoskeletal dysfunctions in people with diabetic neuropathy: the FOotCAre (FOCA) trial I

BACKGROUND

This study is part of a series of two clinical trials. Taking into account the various musculoskeletal alterations of the foot and ankle in people with diabetic peripheral neuropathy (DPN) and the need for self-care to avoid more serious dysfunctions and complications, a self-manageable exercise protocol that focuses on strengthening the foot muscles is presented as a potentially effective preventive method for foot and gait complications. The aim of this trial is to investigate the effect of a customized rehabilitation technology, the Diabetic Foot Guidance System (SOPeD), on DPN status, functional outcomes and gait biomechanics in people with DPN.

METHODS/DESIGN

Footcare (FOCA) trial I is a randomized, controlled and parallel two-arm trial with blind assessment. A total of 62 patients with DPN will be allocated into either a control group (recommended foot care by international consensus with no foot exercises) or an intervention group (who will perform exercises through SOPeD at home three times a week for 12 weeks). The exercise program will be customized throughout its course by a perceived effort scale reported by the participant after completion of each exercise. The participants will be assessed at three different times (baseline, completion at 12 weeks, and follow-up at 24 weeks) for all outcomes. The primary outcomes will be DPN symptoms and severity classification. The secondary outcomes will be foot-ankle kinematics and kinetic and plantar pressure distribution during gait, tactile and vibration sensitivities, foot health and functionality, foot strength, and functional balance.

DISCUSSION

As there is no evidence about the efficacy of rehabilitation technology in reducing DPN symptoms and severity or improving biomechanical, clinical, and functional outcomes for people with DPN, this research can contribute substantially to clarifying the therapeutic merits of software interventions. We hope that the use of our application for people with DPN complications will reduce or attenuate the deficits caused by DPN. This rehabilitation technology is freely available, and we intend to introduce it into the public health system in Brazil after demonstrating its effectiveness.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04011267. Registered on 8 July 2019.

SIGNIFICANCE OF ELECTROMYOGRAPHY IN THE ASSESSMENT OF DIABETIC NEUROPATHY

Diabetic neuropathy is one of the physical complications of diabetes mellitus (DM) patients with a long history of diabetes. An electromyography (EMG)-based assessment may be very useful for the management of diabetic neuropathy. In the present study, we aimed to summarize all of the findings and recommendations obtained from previous studies that investigated the application of EMG to the assessment of diabetic neuropathy. An extensive search of the prominent electronic databases PubMed, Google Scholar and Scopus was performed to evaluate the following areas: (i) what are the muscles to be evaluated by EMG for neuropathy assessment, (ii) what type of EMG methodologies have been used and (iii) what recommendation can be made for neuropathy detection. The major findings are summarized as follows: (i) very few studies have analyzed the correlation of the EMG signals acquired from peripheral muscles affected in neuropathy with those obtained with non-neuropathic complications, such as ankle sprain; (ii) EMG has been applied for the detection of diabetic neuropathy more than diabetes treatment; and (iii) neuropathy detection using an EMG-based assessment were mainly performed for type 2 DM patients aged at least 50 years.

Effects of diabetic peripheral neuropathy on gait in vascular trans-tibial amputees

BACKGROUND

Patients with diabetes often develop diabetic peripheral neuropathy, which is a distal symmetric polyneuropathy, so foot function on the non-amputated side is expected to affect gait in vascular trans-tibial amputees. However, there is little information on the kinematics and kinetics of gait or the effects of diabetic peripheral neuropathy in vascular trans-tibial amputees. This study aimed to clarify these effects, including the biomechanics of the ankle on the non-amputated side.

METHODS

Participants were 10 vascular trans-tibial amputees with diabetic peripheral neuropathy (group V) and 8 traumatic trans-tibial amputees (group T). Each subject's gait was analyzed at a self-selected speed using a three-dimensional motion analyzer and force plates.

FINDINGS

Ankle plantarflexion angle, heel elevation angle, and peak and impulse of anterior ground reaction force were smaller on the non-amputated side during pre-swing in group V than in group T. Center of gravity during pre-swing on the non-amputated side was lower in group V than in group T. Hip extension torque during loading response on the prosthetic side was greater in group V than in group T.

INTERPRETATION

These findings suggest that the biomechanical function of the ankle on the non-amputated side during pre-swing is poorer in vascular trans-tibial amputees with DPN than in traumatic trans-tibial amputees; the height of the center of gravity could not be maintained during this phase in vascular trans-tibial amputees with diabetic peripheral neuropathy. The hip joint on the prosthetic side compensated for this diminished function at the ankle during loading response.

Muscle force distribution of the lower limbs during walking in diabetic individuals with and without polyneuropathy

BACKGROUND

Muscle force estimation could advance the comprehension of the neuromuscular strategies that diabetic patients adopt to preserve walking ability, which guarantees their independence as they deal with their neural and muscular impairments due to diabetes and neuropathy. In this study, the lower limb's muscle force distribution during gait was estimated and compared in diabetic patients with and without polyneuropathy.

METHODS

Thirty individuals were evaluated in a cross-sectional study, equally divided among controls (CG) and diabetic patients with (DNG) and without (DG) polyneuropathy. The acquired ground reaction forces and kinematic data were used as input variables for a scaled musculoskeletal model in the OpenSim software. The maximum isometric force of the ankle extensors and flexors was reduced in the model of DNG by 30% and 20%, respectively. The muscle force was calculated using static optimization, and peak forces were compared among groups (flexors and extensors of hip, knee, and ankle; ankle evertors; and hip abductors) using MANOVAs, followed by univariate ANOVAs and Newman-Keuls post-hoc tests (p < 0.05).

RESULTS

From the middle to late stance phase, DG showed a lower soleus muscle peak force compared to the CG (p=0.024) and the DNG showed lower forces in the gastrocnemius medialis compared to the DG (p=0.037). At the terminal swing phase, the semitendinosus and semimembranosus peak forces showed lower values in the DG compared to the CG and DNG. At the late stance, the DNG showed a higher peak force in the biceps short head, semimembranosus, and semitendinosus compared to the CG and DG.

CONCLUSION

Peak forces of ankle (flexors, extensors, and evertors), knee (flexors and extensors), and hip abductors distinguished DNG from DG, and both of those from CG. Both diabetic groups showed alterations in the force production of the ankle extensors with reductions in the forces of soleus (DG) and gastrocnemius medialis (DNG) seen in both diabetic groups, but only DNG showed an increase in the hamstrings (knee flexor) at push-off. A therapeutic approach focused on preserving the functionality of the knee muscles is a promising strategy, even if the ankle dorsiflexors and plantarflexors are included in the resistance training.

Altered leverage around the ankle in people with diabetes: A natural strategy to modify the muscular contribution during walking?

Diabetes patients display gait alterations compared to controls including a higher metabolic cost of walking. This study aimed to investigate whether differences in external moment arm (ExtMA) and effective mechanical advantage (EMA) at the ankle in diabetes patients could partly explain the increased cost of walking compared to controls. Thirty one non-diabetic controls (Ctrl); 22 diabetes patients without peripheral neuropathy (DM) and 14 patients with moderate/severe diabetic peripheral neuropathy (DPN) underwent gait analysis using a motion analysis system and force plates. The internal Achilles tendon moment arm length was determined using magnetic resonance imaging during weight-bearing and ExtMA was calculated using gait analysis. A greater value (P<0.01) for the EMA at the ankle was found in the DPN (0.488) and DM (0.46) groups compared to Ctrl (0.448). The increased EMA was mainly caused by a smaller ExtMA in the DPN (9.63cm; P<0.01) and DM (10.31cm) groups compared to Ctrl (10.42cm) These findings indicate that the ankle plantarflexor muscles would need to generate lower forces to overcome the external resistance during walking compared to controls. Our findings do not explain the previously observedhigher metabolic cost of walking in the DM and DPN groups, but uncover a new mechanism through which patients with diabetes and particularly those with DPN reduce the joint moment at the ankle during walking: by applying the ground reaction force more proximally on the foot, or at an angle directed more towards the ankle, thereby increasing the EMA and reducing the ankle joint moment.

Kinetics and kinematics of diabetic foot in type 2 diabetes mellitus with and without peripheral neuropathy: a systematic review and meta-analysis

Background

Diabetes mellitus patients are at increased risk of developing diabetic foot with peripheral neuropathy, vascular and musculoskeletal complications. Therefore they are prone to develop frequent and often foot problems with a relative high risk of infection, gangrene and amputation. In addition, altered plantar pressure distribution is an important etiopathogenic risk factor for the development of foot ulcers. Thus the review on study of foot kinematic and kinetic in type 2 diabetes mellitus to understand the biomechanical changes is important.

Methodology

Scientific articles were obtained using electronic databases including Science Direct, CINAHL, Springer Link, Medline, Web of Science, and Pubmed. The selection was completed after reading the full texts. Studies using experimental design with focus on biomechanics of diabetic foot were selected.

Results

The meta-analysis report on gait velocity (neuropathy = 128 and non-diabetes = 131) showed that there was a significantly lower gait velocity in neuropathy participants compared to non-diabetes age matched participants at a high effect level (−0.09, 95 % CI −0.13 to 0.05; p < 0.0001). Regarding knee joint flexion range there was a significant difference between neuropathy and non-diabetes group (4.75, 95 % CI, −7.53 to 1.97, p = 0.0008).

Conclusions

The systematic review with meta-analysis reported significant difference in kinematic and kinetic variables among diabetic with neuropathy, diabetic without neuropathy and non-diabetes individuals. The review also found that the sample size in some studies were not statistically significant to perform the meta-analysis and report a strong conclusion. Therefore a study with higher sample size should be done.

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

AIM

Diabetes Mellitus progressively leads to impairments in stability and joint motion and might affect coordination patterns, mainly due to neuropathy. This study aims to describe changes in intralimb joint coordination in healthy individuals and patients with absent, mild and, severe stages of neuropathy.

METHODS

Forty-seven diabetic patients were classified into three groups of neuropathic severity by a fuzzy model: 18 without neuropathy (DIAB), 7 with mild neuropathy (MILD), and 22 with moderate to severe neuropathy (SVRE). Thirteen healthy subjects were included as controls (CTRL). Continuous relative phase (CRP) was calculated at each instant of the gait cycle for each pair of lower limb joints. Analysis of Variance compared each frame of the CRP time series and its standard deviation among groups (α = 5%).

RESULTS

For the ankle-hip CRP, the SVRE group presented increased variability at the propulsion phase and a distinct pattern at the propulsion and initial swing phases compared to the DIAB and CTRL groups. For the ankle-knee CRP, the 3 diabetic groups presented more anti-phase ratios than the CTRL group at the midstance, propulsion, and terminal swing phases, with decreased variability at the early stance phase. For the knee-hip CRP, the MILD group showed more in-phase ratio at the early stance and terminal swing phases and lower variability compared to all other groups. All diabetic groups were more in-phase at early the midstance phase (with lower variability) than the control group.

CONCLUSION

The low variability and coordination differences of the MILD group showed that gait coordination might be altered not only when frank evidence of neuropathy is present, but also when neuropathy is still incipient. The ankle-knee CRP at the initial swing phase showed distinct patterns for groups from all degrees of neuropathic severity and CTRLs. The ankle-hip CRP pattern distinguished the SVRE patients from other diabetic groups, particularly in the transitional phase from stance to swing.

Is the metabolic cost of walking higher in people with diabetes?

People with diabetes walk slower and display biomechanical gait alterations compared with controls, but it remains unknown whether the metabolic cost of walking (CoW) is elevated. The aim of this study was to investigate the CoW and the lower limb concentric joint work as a major determinant of the CoW, in patients with diabetes and diabetic peripheral neuropathy (DPN). Thirty-one nondiabetic controls (Ctrl), 22 diabetic patients without peripheral neuropathy (DM), and 14 patients with moderate/severe DPN underwent gait analysis using a motion analysis system and force plates and treadmill walking using a gas analyzer to measure oxygen uptake. The CoW was significantly higher particularly in the DPN group compared with controls and also in the DM group (at selected speeds only) compared with controls, across a range of matched walking speeds. Despite the higher CoW in patients with diabetes, concentric lower limb joint work was significantly lower in DM and DPN groups compared with controls. The higher CoW is likely due to energetic inefficiencies associated with diabetes and DPN reflecting physiological and biomechanical characteristics. The lower concentric joint work in patients with diabetes might be a consequence of kinematic gait alterations and may represent a natural strategy aimed at minimizing the CoW.

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

BACKGROUND

Changes in gait patterns in individuals with diabetes and neuropathy are still inconclusive. Our aim was to identify differences in the net intralimb moments distribution and lower limb kinematics during gait in different stage of diabetes.

SUBJECTS AND METHODS

This was an observational cross-sectional study that assessed 38 adults: a control group (n=12), a group with diabetes (n=12), and a group with diabetic neuropathy (n=14). The flexor and extensor joint moment peaks and kinematics of ankle, knee, and hip angles were compared among groups (by analysis of variance).

RESULTS

At initial contact, both diabetes groups present more hip flexion and smaller hip extensor moment. During late midstance, hip extension decreases, and flexion moment increases in both diabetes groups. For the same diabetes groups, during push off, the hip is more flexed, and the hip extensor moment decreases. Only for the diabetes group without neuropathy is the knee markedly more flexed, and the extensor moment is higher than in the other groups. At push off, the ankle is less extended in both diabetes groups, but the ankle extensor moment is significantly smaller only in neuropathic subjects.

CONCLUSIONS

The biomechanical modifications on the gait appeared to be a continuous process that was already revealed in patients without neuropathy. The use of the hip joint as a mechanism of forward progression of the body, instead of using the ankle, was more evident and consistent for the patients with diabetic neuropathy. The knee seems to have a major role in those with diabetes without neuropathy who presented higher extensor moments to support the body during early stance.

What has finite element analysis taught us about diabetic foot disease and its management? A systematic review

Background

Over the past two decades finite element (FE) analysis has become a popular tool for researchers seeking to simulate the biomechanics of the healthy and diabetic foot. The primary aims of these simulations have been to improve our understanding of the foot’s complicated mechanical loading in health and disease and to inform interventions designed to prevent plantar ulceration, a major complication of diabetes. This article provides a systematic review and summary of the findings from FE analysis-based computational simulations of the diabetic foot.

Methods

A systematic literature search was carried out and 31 relevant articles were identified covering three primary themes: methodological aspects relevant to modelling the diabetic foot; investigations of the pathomechanics of the diabetic foot; and simulation-based design of interventions to reduce ulceration risk.

Results

Methodological studies illustrated appropriate use of FE analysis for simulation of foot mechanics, incorporating nonlinear tissue mechanics, contact and rigid body movements. FE studies of pathomechanics have provided estimates of internal soft tissue stresses, and suggest that such stresses may often be considerably larger than those measured at the plantar surface and are proportionally greater in the diabetic foot compared to controls. FE analysis allowed evaluation of insole performance and development of new insole designs, footwear and corrective surgery to effectively provide intervention strategies. The technique also presents the opportunity to simulate the effect of changes associated with the diabetic foot on non-mechanical factors such as blood supply to local tissues.

Discussion

While significant advancement in diabetic foot research has been made possible by the use of FE analysis, translational utility of this powerful tool for routine clinical care at the patient level requires adoption of cost-effective (both in terms of labour and computation) and reliable approaches with clear clinical validity for decision making.

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.

Comparison of foot segmental mobility and coupling during gait between patients with diabetes mellitus with and without neuropathy and adults without diabetes

BACKGROUND

Reduction in foot mobility has been identified as a key factor of altered foot biomechanics in individuals with diabetes mellitus. This study aimed at comparing in vivo segmental foot kinematics and coupling in patients with diabetes with and without neuropathy to control adults.

METHODS

Foot mobility of 13 diabetic patients with neuropathy, 13 diabetic patients without neuropathy and 13 non-diabetic persons was measured using an integrated measurement set-up including a plantar pressure platform and 3D motion analysis system. In this age-, sex- and walking speed matched comparative study; differences in range of motion quantified with the Rizzoli multisegment foot model throughout different phases of the gait cycle were analysed using one-way repeated measures analysis of variance (ANOVA). Coupling was assessed with cross-correlation techniques.

FINDINGS

Both cohorts with diabetes showed significantly lower motion values as compared to the control group. Transverse and sagittal plane motion was predominantly affected with often lower range of motion values found in the group with neuropathy compared to the diabetes group without neuropathy. Most significant changes were observed during propulsion (both diabetic groups) and swing phase (predominantly diabetic neuropathic group). A trend of lower cross-correlations between segments was observed in the cohorts with diabetes.

INTERPRETATION

Our findings suggest an alteration in segmental kinematics and coupling during walking in diabetic patients with and without neuropathy. Future studies should integrate other biomechanical measurements as it is believed to provide additional insight into neural and mechanical deficits associated to the foot in diabetes.

Integrated kinematics-kinetics-plantar pressure data analysis: a useful tool for characterizing diabetic foot biomechanics

The fundamental cause of lower-extremity complications in diabetes is chronic hyperglycemia leading to diabetic foot ulcer pathology. While the relationship between abnormal plantar pressure distribution and plantar ulcers has been widely investigated, little is known about the role of shear stress. Moreover, the mutual relationship among plantar pressure, shear stress, and abnormal kinematics in the etiology of diabetic foot has not been established. This lack of knowledge is determined by the lack of commercially available instruments which allow such a complex analysis. This study aims to develop a method for the simultaneous assessment of kinematics, kinetics, and plantar pressure on foot subareas of diabetic subjects by means of combining three commercial systems. Data were collected during gait on 24 patients (12 controls and 12 diabetic neuropathics) with a motion capture system synchronized with two force plates and two baropodometric systems. A four segment three-dimensional foot kinematics model was adopted for the subsegment angles estimation together with a three segment model for the plantar sub-area definition during gait. The neuropathic group exhibited significantly excessive plantar pressure, ground reaction forces on each direction, and a reduced loading surface on the midfoot subsegment (p<0.04). Furthermore the same subsegment displayed excessive dorsiflexion, external rotation, and eversion (p<0.05). Initial results showed that this methodology may enable a more appropriate characterization of patients at risk of foot ulcerations, and help planning prevention programs.

Effects of a combined strengthening, stretching and functional training program versus usual-care on gait biomechanics and foot function for diabetic neuropathy: a randomized controlled trial

Background

Polyneuropathy is a complication of diabetes mellitus that has been very challenging for clinicians. It results in high public health costs and has a huge impact on patients' quality of life. Preventive interventions are still the most important approach to avoid plantar ulceration and amputation, which is the most devastating endpoint of the disease. Some therapeutic interventions improve gait quality, confidence, and quality of life; however, there is no evidence yet of an effective physical therapy treatment for recovering musculoskeletal function and foot rollover during gait that could potentially redistribute plantar pressure and reduce the risk of ulcer formation.

Methods/Design

A randomised, controlled trial, with blind assessment, was designed to study the effect of a physiotherapy intervention on foot rollover during gait, range of motion, muscle strength and function of the foot and ankle, and balance confidence. The main outcome is plantar pressure during foot rollover, and the secondary outcomes are kinetic and kinematic parameters of gait, neuropathy signs and symptoms, foot and ankle range of motion and function, muscle strength, and balance confidence. The intervention is carried out for 12 weeks, twice a week, for 40-60 min each session. The follow-up period is 24 weeks from the baseline condition.

Discussion

Herein, we present a more comprehensive and specific physiotherapy approach for foot and ankle function, by choosing simple tasks, focusing on recovering range of motion, strength, and functionality of the joints most impaired by diabetic polyneuropathy. In addition, this intervention aims to transfer these peripheral gains to the functional and more complex task of foot rollover during gait, in order to reduce risk of ulceration. If it shows any benefit, this protocol can be used in clinical practice and can be indicated as complementary treatment for this disease.

Trial Registration

ClinicalTrials.gov Identifier: NCT01207284

Effect of simulated leg length discrepancy on plantar pressure distribution in diabetic patients with neuropathic foot ulceration

OBJECTIVE

To study the effect of a minor degree of artificially induced leg length discrepancy (LLD) on plantar pressure distribution in diabetic patients with neuropathic foot ulceration.

METHOD

In-shoe plantar pressure distributions were measured on the ulcerated foot during walking using F-scan (Tekscan Inc.). To simulate minor LLD, the contralateral leg length was changed by asking patients to walk under three different conditions: wearing shoe of the same sole thickness (NLLD), walking with a bare foot (20mm long leg) and wearing a 40mm-high platform-sole shoe (20mm short leg). These three different walking conditions were compared in a randomised, single-blinded crossover design.

RESULTS

The study included 28 diabetic patients with neuropathic foot ulcers (53.7 ± 6.8 years; 16 males, 12 female). Notably, the peak pressure and pressure time integral (PTI) were the most affected parameters. PTI significantly increased beneath total foot, mid-foot, 2nd, 3rd, 4th and 5th metatarsal heads (MTHs), and 3rd toe, when the 20mm short leg was simulated (79.4 ± 21.1; 61.5 ± 32.3; 59.9 ± 36.5; 69 ± 42.1; 70.6 ± 42.3; 63.9 ± 33.7; 40.± 33.2 kPa·s, respectively), compared with NLLD (73.7 ± 19.9; 55.524; 51.8 ± 30.1; 58.4 ± 37.6; 60.3 ± 39.5; 57.2 ± 32.3; 36.9 ± 33.3 kPa·s, respectively).

CONCLUSION

The short leg of diabetic patients with neuropathic foot ulcers will be subjected to greater pressure load, primarily beneath the total foot, mid-foot and 2nd, 3rd, 4th and 5th metatarsal heads. As such, care should be taken to avoid minor LLD, as it could inadvertently develop on using offloading devices.

DECLARATION OF INTEREST

The authors have nothing to declare.

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.

Gastrocnemius recession as an alternative to tendoAchillis lengthening for relief of forefoot pressure in a patient with peripheral neuropathy: a case report and description of a technical modification

The gastrocnemius recession is a popular surgical procedure for the treatment of equinus contracture. Lengthening the gastrocnemius tendon has been show to be an effective means of reducing pressure to the plantar forefoot by weakening the triceps surae complex. The more traditional method of weakening the triceps surae is a modification of Hoke's triple hemisection through the tendoAchillis. This technique unfortunately carries a serious risk of the development of a calcaneal gait. The purpose of this case report is to demonstrate that the gastrocnemius recession is an effective and safe alternative to the traditional tendoAchillis lengthening. The authors also describe a minimally invasive technique that uses a pediatric speculum for a self-retrained retractor and portal for instrumentation and visualization.

A comparison of lower limb EMG and ground reaction forces between barefoot and shod gait in participants with diabetic neuropathic and healthy controls

Background

It is known that when barefoot, gait biomechanics of diabetic neuropathic patients differ from non-diabetic individuals. However, it is still unknown whether these biomechanical changes are also present during shod gait which is clinically advised for these patients. This study investigated the effect of the participants own shoes on gait biomechanics in diabetic neuropathic individuals compared to barefoot gait patterns and healthy controls.

Methods

Ground reaction forces and lower limb EMG activities were analyzed in 21 non-diabetic adults (50.9 ± 7.3 yr, 24.3 ± 2.6 kg/m²) and 24 diabetic neuropathic participants (55.2 ± 7.9 yr, 27.0 ± 4.4 kg/m²). EMG patterns of vastus lateralis, lateral gastrocnemius and tibialis anterior, along with the vertical and antero-posterior ground reaction forces were studied during shod and barefoot gait.

Results

Regardless of the disease, walking with shoes promoted an increase in the first peak vertical force and the peak horizontal propulsive force. Diabetic individuals had a delay in the lateral gastrocnemius EMG activity with no delay in the vastus lateralis. They also demonstrated a higher peak horizontal braking force walking with shoes compared to barefoot. Diabetic participants also had a smaller second peak vertical force in shod gait and a delay in the vastus lateralis EMG activity in barefoot gait compared to controls.

Conclusions

The change in plantar sensory information that occurs when wearing shoes revealed a different motor strategy in diabetic individuals. Walking with shoes did not attenuate vertical forces in either group. Though changes in motor strategy were apparent, the biomechanical did not support the argument that the use of shoes contributes to altered motor responses during gait.

Effect of reduced cutaneous cues on motion perception and postural control

To investigate whether the sensory perception could be a more direct assessment of sensory deficit as oppose to the postural performance, we examined the effect of reduced cutaneous cues on motion perception and motion control. The subject was translated in a mediolateral direction with a single sinusoidal acceleration at a stimulus frequency of 0.25 Hz with a peak acceleration magnitude ranging from 0.25 to 8 mG in the dark. Two different plantar cutaneous conditions were provided: the control condition (barefoot) and the reduced cutaneous condition (foot on a spongy surface). For each foot-sole sensory condition, the subject completed six sets of 33 randomly ordered translation stimuli. After each translational stimulus, the subject reported their perceived direction of motion by pressing a hand-held button. The center of pressure (COP) and joint kinematics of the quiet stance were also measured. The results showed a significant increase in perception threshold as well as COP variation in the anteroposterior direction in the reduced cutaneous cue trials. However, a non-significant increase in COP in the mediolateral direction was shown. Multivariate covariance analysis of joint kinematics showed changes in postural coordination, such as increased reliance on hip strategy under reduced cutaneous cues condition, that have not been differentiated by univariate measures. The observed discrepancy in the significance of the contribution of plantar cutaneous cues to the detection threshold and the COP variation implies that the 'perception' could provide more direct and sensitive assessment of the sensory degradation than the 'action'.

Faster walking speeds increase local instability among people with peripheral neuropathy

Individuals with peripheral neuropathy (PN) may compensate for decreased somatosensation by reducing walking speed. Predisposition to falls may therefore arise from an inability to adapt to challenging walking speeds. The purpose of this study was to examine the effects of PN on the magnitude of variability and local instability on walking at different speeds. Twelve individuals with PN and 12 controls completed a 6-min walk test to determine fast walking speed (FWS). Sagittal plane hip, knee, and ankle joint angles were then calculated during 3 min of treadmill walking at 100%, 80%, and 60% FWS. The magnitudes of stride duration variability (SDvar), joint angle variability (JTvar), and both short- and long-term Lyapunov exponents (used to estimate local instability) were calculated. The PN group walked slower than the control group (p<.001). With groups combined, walking faster led to increased local instability and increased variability (p<.001). The PN group exhibited increased variability (SDvar, p=.02; JTvar, p=.01) over all speeds, and exaggerated local instability (p<.05) when walking at the fastest speed. PN leads to increased walking variability and local instability, particularly when walking at challenging speeds. These results are important to consider in future patient education and rehabilitation programs.