The relationship between passive range of motion and range of motion during gait and plantar pressure measurements

Examination time-distance characteristics of gait and pelvic kinematics in individuals with Diabetic polyneuropathy: a case-control study

BACKGROUND

Diabetic Peripheral Neuropathy (DPN) disrupts body and movement biomechanics, increases mechanical stress during walking, and predisposes individuals to injuries owing to the repetitive effects of these stresses.

AIMS

This study aimed to assess and compare the impact of neuropathy on gait and pelvic kinematics in individuals with DPN.

METHODS

This case-control study included two groups: 23 individuals diagnosed with DPN aged between 35-70 and 23 healthy individuals aged-35-70. The BTS-G, a wireless motion sensor, was used to assess the time-distance characteristics of walking in all participants. The system analyzed data pertaining to walking speed, cadence, percentages of stance and swing phases, durations of walking cycles, double-step lengths, pelvic tilt, obliquity, and rotation symmetries.

RESULTS

There were no statistically significant differences between the groups in cadence, left and right stance phase percentages, or left and right swing phase percentages (p > 0.05). However, significant differences were observed between the groups in terms of speed, left and right walking cycle durations, and left and right double-step lengths (p < 0.05). Additionally, no statistically significant difference was found between the groups in pelvic tilt symmetry and left and right pelvic tilt range of motion values (p > 0.05). Nevertheless, significant differences were identified between the groups in pelvic obliquity symmetry, pelvic rotation symmetry, left and right pelvic obliquity range of motion, and left and right pelvic rotation range of motion values (p < 0.05).

CONCLUSIONS

The findings of this study suggest that individuals with DPN exhibit decreased walking speed, prolonged gait cycle duration, increased double step length, and reduced pelvic obliquity and rotation range of motion.

Immediate Effects of Weight-Bearing Calf Stretching on Ankle Dorsiflexion Range of Motion and Plantar Pressure During Gait in Patients with Diabetes Mellitus

High plantar pressure is a risk factor for diabetic foot ulcers, and it is known that restriction of ankle dorsiflexion range of motion (ROM) causes high plantar pressure. Stretching is a non-invasive and general means to improve ROM; however, the effect of stretching on the ROM and plantar pressure has not been clarified in patients with diabetes mellitus. We aimed to study the effects of intermittent weight-bearing stretching on ankle dorsiflexion ROM and plantar pressure during gait in patients with diabetes mellitus. Seven patients with diabetes mellitus participated, and their triceps surae was stretched using weight-bearing stretching with a stretch board. Five minutes of stretching was performed 4 times with a rest interval of 30 s. Ankle dorsiflexion ROM was measured with the knee flexed and extended. Peak pressure and pressure-time integral during gait were measured and calculated for the rearfoot, midfoot, forefoot, and total plantar surface before and after stretching. Ankle dorsiflexion ROM with the knee extended or bent increased significantly after stretching (P < .05). Peak pressure and the pressure-time integral decreased significantly, especially in the forefoot (P < .01), and these also decreased significantly in the total plantar surface (P < .05). The duration of foot-flat decreased after stretching (P < .05). Weight-bearing stretching improved ankle dorsiflexion ROM and reduced plantar pressure during gait. These results suggest that weight-bearing calf stretching may be an effective means to prevent and treat diabetic foot ulcers.

The pressure time integral: An underused, clinically significant parameter as a determinant of neuropathic ulceration in diabetes

BACKGROUND

The purpose of this study was to evaluate plantar pressure dynamics in the occurrence of active diabetic neuropathic ulceration (DNU) and any changes in loadings occurring in individuals with a history of diabetic neuropathic ulceration (DHNU). Since current gold standard offloading strategies are not producing desirable healing outcomes and optimum ulcer prevention, this study aimed to better understand the effect of diabetic peripheral neuropathy (DPN) and ulceration on mean peak plantar pressure (MPPP) and pressure-time integral (PTI) changes.

RESEARCH QUESTION

Is there a redistribution of plantar pressure during gait in the presence of active and history of diabetic neuropathic ulceration?

METHODS

A prospective, cross-sectional study was conducted, in which, eighty adult participants were divided into four groups, namely, the DM, DPN, DNU and DHNU groups. Participants were instructed to walk barefoot over a Tekscan HR Mat™ at self-selected speed. MPPP and PTI data were analysed under five forefoot anatomical landmarks and compared between individuals with and without active neuropathic ulceration.

RESULTS

Minimal MPPP significant changes were observed between ulcerated and non-ulcerated groups, however, PTI values were significantly increased in the ulcerated groups under all plantar ulceration regions. No significant plantar pressure differences were observed between the DNU and DHNU groups. Logistic regression tests demonstrated that as PTIs under the hallux increase, the likelihood of an individual living with DPN developing ulceration increases.

SIGNIFICANCE

A significant increase in PTI values in the presence of ulceration highlights the importance of evaluating the duration of loads under forefoot regions during gait rather than just focusing on the magnitude of pressures during ulcer management and prevention. Moreover, results show that PTI values remain high in the presence of a history of neuropathic ulceration, possibly demonstrating the value of PTI as a clinical tool over MPPP in the assessment of the high-risk diabetic foot.

Acute Effects of Combination Therapy by Triceps Surae Stretching and Electrical Stimulation to the Tibialis Anterior on Medial Forefoot Plantar Pressure During Gait in Patients With Diabetes Mellitus

High plantar flexor moment and limited ankle mobility are known to cause high plantar pressure under the forefoot. Stretching is an effective physical therapy for the limited ankle range of motion (ROM), and electrical stimulation is used to regulate the activity of antagonistic muscle via the action of reciprocal inhibition. Additionally, stretching paired with electrical stimulation has been reported to improve the limited ROM significantly. This study aims to investigate the influences of stretching on triceps surae (STR), electrical stimulation to tibialis anterior (ES), and the combination (ES+STR) on the ROM, kinematic parameters, and plantar pressure distribution during gait in patients with diabetes mellitus. Planter pressure and other parameters were measured before and after the intervention of ES, STR, ES+STR, or the rest sitting on the bed (CON) for 10 min. Pressure time integral under the medial forefoot decreased in the ES+STR compared to CON (P< .05). Interestingly, ES+STR increased passive and dynamic ROM on ankle dorsiflexion during gait and increased the lateral center of pressure excursion (P < .05). Furthermore, these changes were followed by decreased contact duration under the medial forefoot (P < .05). The combined therapy improves ankle mobility during gait and reduces the contact duration and the plantar pressure under the medial forefoot in patients with diabetes mellitus.

Alterations to plantar loading and ankle range of motion of the contralateral foot during assisted walking in patients with Type 2 Diabetes Mellitus

AIMS

Patients with diabetic foot ulcers are instructed to be non-weight bearing on the affected limb to promote healing. Therefore, the aim of this study was to investigate the effect of different assistive devices on whole foot plantar loading, peak forefoot force, ankle range of motion, and locomotion speed during gait in patients with Type 2 Diabetes Mellitus.

METHODS

Participants walked normally, with crutches, a walker, and a wheeled knee walker (WKW) in randomized order. Force sensitive insoles and 3D motion capture were used to record plantar normal force and ankle kinematics. Force sensitive pads were wrapped around handles of the crutches and walker to measure bodyweight offloaded onto the assistive device. An instrumented WKW was used to measure bodyweight offloaded onto the handlebars and knee cushion.

RESULTS

Locomotion with the WKW produced the lowest whole foot plantar loading and peak forefoot force in the propulsive limb, while also producing the greatest ankle range of motion and locomotion speed amongst assistive devices.

CONCLUSIONS

This pre-clinical study found that the WKW could be the preferred assistive device for total unilateral offloading of diabetic foot ulcers as it reduced propulsive limb whole foot and forefoot plantar loading while retaining ankle range of motion and locomotion speed.

Biomechanical modelling of diabetic foot ulcers: A computational study

Diabetic foot problems are widespread globally, resulting in substantial medical, economic, and social challenges for patients and their families. Among diabetic complications, foot ulceration is the most frequent outcome and is more probable to be of neuropathic origin. To date, a plethora of studies has focused on diabetic foot and ulcer prevention. However, limited studies have investigated the biomechanics of diabetic foot post ulceration. In this work, extensive biomechanical modelling of diabetic foot ulcers was attempted. A full-scale foot model was developed using measurements from a human subject, and ulcers of differing sizes and depths were modelled at different plantar sites numerically. Also, the foot model was computationally modified to study the effect of flat foot conditions on the same diabetic ulcers. Standing condition was simulated, and the induced stresses were investigated at the plantar region. The maximum stresses were observed to be similar for all ulcer sizes and depths at the lateral midfoot region of the normal foot. However, the maximum stresses were reported in the lateral heel region for the flat foot, which varied significantly with size and depth. Such results present important information on the foot condition post ulceration and may help identify possibilities of further ulceration in the diabetic foot. These novel findings are anticipated to be indispensable for the development of suitable interventions (e.g., custom orthotics) for diabetic foot ulcer management.

The effect of induced joint restriction on plantar pressure during gait - a pilot study

BACKGROUND

The aim of this study was to analyse the effect of induced lower limb joint restriction on plantar pressures during gait. Focusing on restricting a single joint, without the effect of other co-morbidities, would provide better understanding as to the resultant plantar loadings during gait, which would be especially beneficial in patients requiring offloading procedures.

RESEARCH QUESTION

Does induced lower limb joint restriction affect plantar pressure distribution during gait?

METHODS

A prospective, quasi-experimental study was conducted, recruiting ten healthy, adult participants who were instructed to walk barefoot over a Tekscan HR Mat™. This procedure was repeated after separately inducing restriction of the hip, knee and ankle joints. Mean peak plantar pressure (MPP) and pressure-time integral (PTI) data were analysed to compare between unrestricted and restricted data.

RESULTS

Significant plantar pressure changes were observed in the heel and first metatarsal regions. Rearfoot PTIs were increased with restriction of the contralateral hip (left p <0.001) (right p =0.02) and knee joints (left p =0.01) (right p =0.04). Both MPPs (left p =0.01; right p =0.01) and PTIs (left p =0.004; right p =0.03) were increased in the first metatarsal when restricting the hip joint of the same limb. MPP was decreased in the left first metatarsal with induced knee (left p =0.01; right p =0.04) and ankle (left and right p <0.001) joint restriction. Finally, MPP was decreased in the right first metatarsal with knee (left and right p =0.01) and ankle (left p =0.04; right p =0.01) joint restriction.

SIGNIFICANCE

Limited joint mobility may have a direct effect on plantar pressure, particularly with restriction in the hip and knee joints, hence careful attention should be given especially in patients with conditions involving plantar loadings. Results in this study also show that PTI changes during gait should be equally evaluated clinically along with peak plantar pressure analysis.

Using Manchester Scale classification of Hallux Valgus as a valuable tool in determining appropriate risk categorization during initial diabetic foot screening in primary health care settings

Limitations have been identified in the current state of primary care practises with regards to identifying and correctly categorizing foot deformity and its associated risk of developing foot ulcers in patients with diabetes. This study aims to bridge these gaps through the implementation of additional categorization tools to be made available for primary care professionals. This study thus analysed the relationship between foot pressure distribution and amount in patients with diabetes with Hallux Valgus foot deformity, and its different stages, in order to better understand the clinical applications of the Manchester Scale. Statistically significant data in pressure distribution (P < 0.05) was found in all three severity groups identified by the Manchester Scale (Mild, Moderate and Severe) when compared to a No deformity group. However, only the Severe Hallux Valgus group crossed the threshold over 500 kPa in the area of first metatarsal bone. Further research should aim to analyse pressure distribution and amount in patients with both diabetes and diabetic neuropathy of all stages of Hallux Valgus.

Effectiveness of customized insoles on maximum plantar pressure in diabetic foot syndrome: A systematic review

BACKGROUND AND AIMS

Diabetic foot syndrome is a severe complication of type 2 diabetes mellitus with diabetic peripheral neuropathy. Increased maximum plantar pressure is a strong predictor that may be detrimental and cause a plantar ulcer. This present systematic review aims to evaluate the effectiveness of customized insoles on reducing maximum plantar pressure in diabetic foot syndrome.

METHODS

We conducted a systematic review (PubMed, Cochrane Database of Systematic Reviews, CINAHL, Pedro, Scopus) to summarize the evidence on the customized insole on maximum plantar pressure in diabetic foot syndrome. Randomized and non-randomized studies were included in the review. The quality of the included studies was assessed independently by the two review authors with the Modified Downs and Black checklist for the assessment of the methodological quality of both randomized and non-randomized studies.

RESULTS

A total of 1512 studies screened. After the exclusion criteria, 5 studies were included in the study. The outcome measure that was considered is maximum plantar pressure and pressure-time integral.

CONCLUSIONS

We concluded that the practice of customized insoles could significantly reduce maximum plantar pressure. While developing an insole, parameters like contoured insoles with shape and pressure based, weight-bearing position, and duration with good adherence to footwear application can significantly reduce maximum plantar pressure.

Gait changes in persons with diabetes: Early risk marker for diabetic foot ulcer

Background Increasing prevalence of diabetic foot ulcer (DFU) and subsequent foot amputation in persons with type 2 diabetic neuropathy is a well known fact. The present study was aimed to identify the initial risk marker for DFU. Methods Dynamic plantar pressure analysis was done for persons with type 2 diabetes mellitus (T2DM) without neuropathy (D), patients with diabetic neuropathy (DN) with normal foot profile and healthy persons with normal foot profile (C). Results The data showed a significant difference in dynamic peak plantar pressure between C and DN (P = 0.035) and no significant difference between D and DN (P = 0.997). The dynamic segmental peak plantar pressure results showed significant difference only in the medial heel region (P = 0.009) among the three groups. Conclusions Gait variations and restrictions in subtalar and first metatarsophalangeal joint are found in persons with diabetic neuropathy even before the onset of foot deformity.

The Biomechanics of Diabetes Mellitus and Limb Preservation

Biomechanical changes to the lower extremity in patients with diabetes mellitus are typically greatest with peripheral neuropathy, although peripheral arterial disease also impacts limb function. Changes to anatomic structures can impact daily function. These static changes, coupled with kinetic and kinematic changes of gait, lead to increased vertical and shear ground reactive forces, resulting in ulcerations. Unsteadiness secondary to diminished postural stability and increased sway increase fall risk. These clinical challenges and exacerbation of foot position and dynamic changes associated with limb salvage procedures, amputations, and prostheses are necessary and can impact daily function, independence, quality of life, and mortality.

Range of motion of the ankle joint in male Japanese patients undergoing hemodialysis: influence of diabetes and hemodialysis

[Purpose] The purpose of this study was to analyze ankle range of motion in patients undergoing hemodialysis and those with diabetes. [Participants and Methods] Eight male kidney disease patients without diabetes undergoing hemodialysis and 10 male kidney disease patients with diabetes undergoing hemodialysis were enrolled in this study. For comparison, 27 patients with diabetes not undergoing hemodialysis and 10 healthy participants were included. All participants were divided into 4 groups: patients without diabetes undergoing hemodialysis, patients with diabetes undergoing hemodialysis, patients with diabetes not undergoing hemodialysis, and control group. The measured parameter was the passive range of motion of the ankle joint. [Results] Patients with diabetes not undergoing hemodialysis demonstrated the greatest joint restriction, followed by patients with diabetes undergoing hemodialysis. The main effect of diabetes was observed in ankle range of motion, rather than hemodialysis. There was a significant difference between both the diabetes undergoing hemodialysis and the diabetes not undergoing hemodialysis groups and the other groups. [Conclusion] Limited joint mobility of the ankle in patients undergoing hemodialysis may be affected by diabetes rather than hemodialysis.

Relationship between range of motion of foot joints and amount of physical activity in middle-aged male diabetic patients

[Purpose] This study aimed to verify the relationship between foot range of motion and the amount of physical activity in diabetic patients. [Participants and Methods] There were twenty-eight male patients with diabetes (age ranged from 50 to 69 years old) and 10 healthy, non-diabetic male individuals within the same age range in the diabetes group and control group, respectively. The passive ranges of motion of the following joints were measured in the right foot of each participant: the ankle joint, the first metatarsophalangeal joint, and the subtalar joint. The amount of daily physical activity was estimated using the short Japanese version of the International Physical Activity Questionnaire. [Results] The mean range of motion of the ankle joints in the diabetic and control groups was 55.4 ± 8.4° and 69.1 ± 9.2°, respectively, whereas the mean range of motion of the first metatarsophalangeal joints in the diabetic and control groups was 82.9 ± 9.6° and 96.3 ± 8.9°, respectively. The diabetic group showed a significantly higher restriction in joint range of motion than did the control group. The amount of physical activity was a contributing factor toward the ankle range of motion according to multiple regression analysis. [Conclusion] We determined that the range of motion in the ankle joints of diabetic patients was affected by their level of physical activity.

Plantar pressure distribution in diverse stages of diabetic neuropathy

Background

Diabetic Foot Ulceration in patients with diabetes could be associated with high plantar pressure caused by diabetes neuropathy. Therefore, it seems that one of the ways of identifying high-risk legs in diabetic patients with neuropathy would be characterization of elevated plantar pressure distributions.

Objective

Comparing the plantar pressure distribution in diabetic patients who suffered neuropathy with those without neuropathy.

Methods and materials

Plantar pressure distribution was recorded in the following categories: 38 diabetic patients without neuropathy, 30, 40 and 34 patients with mild neuropathy, moderate and severe neuropathy respectively.

Results

Patients suffered from severe neuropathy suggested higher maximum peak plantar pressure at midfoot, heel, and medial forefoot. The peak pressure of midfoot was significantly different in the following categories as well: patient without neuropathy (32.3 ± 17.9 kPa), mild neuropathic (24.0 ± 17.9 kPa), moderate neuropathic (21.5 ± 12.6 kPa), and severe neuropathic (22.9 ± 10.7 kPa) groups (p = 0.02).

Conclusion

The progression of diabetic neuropathy would have been increased followed by the peak plantar pressure.

History, Prevalence and Assessment of Limited Joint Mobility, from Stiff Hand Syndrome to Diabetic Foot Ulcer Prevention: A Narrative Review of the Literature

BACKGROUND

Limited Joint Mobility (LJM) is a dreaded complication of Diabetes Mellitus (DM). During the last half century, LJM has been studied in patients of different age because it has been considered useful for the monitoring of a patient's condition and for the prevention of vascular disease and diabetic foot.

OBJECTIVES

The main aims of this review are to describe the relationship between DM and joint mobility as well as its prevalence and assessment. We have also investigated the role of LJM in the development of diabetic foot ulcers.

METHODOLOGY

An in-depth literature search was conducted to identify studies that examined the prevalence and characteristics of LJM in patients with DM of different types, age, durations and chronic complications.

RESULTS

Many factors (therapy improvements, population characteristics and different evaluation methods) concur to hinder an exact assessment of the prevalence of LJM. However, it has been confirmed that LJM is widespread among patients with DM and may affect more than two-thirds of them in addition to being a major risk factor for foot ulcer. Its role in the monitoring of a patient's condition is also important for the definition of risk thresholds such as in patients with diabetic foot. The efficacy of exercise therapy for the treatment of LJM, also in patients at risk of foot ulcer, has not been discussed.

CONCLUSION

Difficulties encountered in the definition of the prevalence of LJM may hinder its study and the establishment of preventive interventions. However, LJM plays a key role in the monitoring of patients, especially those at risk for ulcer.

Diabetic Neuropathy and Gait: A Review

Diabetic peripheral neuropathy (DPN) is a major sequela of diabetes mellitus and may have a detrimental effect on the gait of people with this complication. DPN causes a disruption in the body's sensorimotor system and is believed to affect up to 50% of patients with diabetes mellitus, dependent on the duration of diabetes. It has a major effect on morbidity and mortality. The peripheral nervous system controls the complex series of events in gait through somatic and autonomic functions, careful balancing of eccentric and concentric muscle contractions and a reliance on the sensory information received from the plantar surface. In this literature review focussing on kinetics, kinematics and posture during gait in DPN patients, we have identified an intimate link between DPN and abnormalities in gait and demonstrated an increased risk in falls for older patients with diabetes. As such, we have identified a need for further research on the role of gait abnormalities in the development of diabetic foot ulceration and subsequent amputations.

Challenging the foundations of the clinical model of foot function: further evidence that the root model assessments fail to appropriately classify foot function

BACKGROUND

The Root model of normal and abnormal foot function remains the basis for clinical foot orthotic practice globally. Our aim was to investigate the relationship between foot deformities and kinematic compensations that are the foundations of the model.

METHODS

A convenience sample of 140 were screened and 100 symptom free participants aged 18-45 years were invited to participate. The static biomechanical assessment described by the Root model was used to identify five foot deformities. A 6 segment foot model was used to measure foot kinematics during gait. Statistical tests compared foot kinematics between feet with and without foot deformities and correlated the degree of deformity with any compensatory motions.

RESULTS

None of the deformities proposed by the Root model were associated with distinct differences in foot kinematics during gait when compared to those without deformities or each other. Static and dynamic parameters were not correlated.

CONCLUSIONS

Taken as part of a wider body of evidence, the results of this study have profound implications for clinical foot health practice. We believe that the assessment protocol advocated by the Root model is no longer a suitable basis for professional practice. We recommend that clinicians stop using sub-talar neutral position during clinical assessments and stop assessing the non-weight bearing range of ankle dorsiflexion, first ray position and forefoot alignments and movement as a means of defining the associated foot deformities. The results question the relevance of the Root assessments in the prescription of foot orthoses.

Novel dynamic peak and distribution plantar pressure measures on diabetic patients during walking

Diabetic peripheral neuropathy (DPN) is a common complication leading to foot ulceration and amputation. Several kinematic, kinetic and plantar pressure measures have been proposed for DPN detection, however findings have been inconsistent. In this work, we present new shape features that capture variations in the plantar pressure using shape and entropy measures to the study of patients with retinopathy, DPN and nephropathy, and a control diabetic group with no complications. The change in the peak plantar pressure (PPP) position with each step for both feet was represented as a convex polygon, asymmetry index, area of the convex polygon, 2nd wavelet moment (WM2) and sample entropy (SamEn). WM2 and the SamEn were more sensitive in capturing variations due to presence of complications than the area and asymmetry measures. WM2 of the left heel (median: 1st IQ, 3rd IQ): 8.27 (4.6,14.8) and left forefoot: 9.2 (2.4,16) were significantly lower for the DPN group compared to the control (CONT) group (heel 11.9 (5.0,16.4); forefoot: 10.3 (4.4,21.3), p < 0.05). SamEn for the DPN group was significantly lower in the right foot compared to the left foot (1.3 (1.26, 1.37) and 1.33 (1.26,1.4), p < 0.01) compared to CONT (right foot: 1.37 (1.24,1.45) and left foot: 1.34 (1.25,1.42), P < 0.05). These new shape and regularity features have shown promising results in detecting diabetic peripheral neuropathy and warrant further investigation.

The prevention of diabetic foot ulceration: how biomechanical research informs clinical practice

Background

Implementation of interprofessional clinical guidelines for the prevention of neuropathic diabetic foot ulceration has demonstrated positive effects regarding ulceration and amputation rates. Current foot care recommendations are primarily based on research regarding the prevention of ulcer recurrence and focused on reducing the magnitude of plantar stress (pressure overload). Yet, foot ulceration remains to be a prevalent and debilitating consequence of Diabetes Mellitus. There is limited evidence targeting the prevention of first-time ulceration, and there is a need to consider additional factors of plantar stress to supplement current guidelines.

Objectives

The first purpose of this article is to discuss the biomechanical theory underpinning diabetic foot ulcerations and illustrate how plantar tissue underloading may precede overloading and breakdown. The second purpose of this commentary is to discuss how advances in biomechanical foot modeling can inform clinical practice in the prevention of first-time ulceration.

Discussion

Research demonstrates that progressive weight-bearing activity programs to address the frequency of plantar stress and avoid underloading do not increase ulceration risk. Multi-segment foot modeling studies indicate that dynamic foot function of the midfoot and forefoot is compromised in people with diabetes. Emerging research demonstrates that implementation of foot-specific exercises may positively influence dynamic foot function and improve plantar stress in people with diabetes.

Conclusion

Continued work is needed to determine how to best design and integrate activity recommendations and foot-specific exercise programs into the current interprofessional paradigm for the prevention of first-time ulceration in people with Diabetes Mellitus.

Reliability of metatarsophalangeal and ankle joint torque measurements by an innovative device

The toe flexor muscles maintain body balance during standing and provide push-off force during walking, running, and jumping. Additionally, they are important contributing structures to maintain normal foot function. Thus, weakness of these muscles may cause poor balance, inefficient locomotion and foot deformities. The quantification of metatarsophalangeal joint (MPJ) stiffness is valuable as it is considered as a confounding factor in toe flexor muscles function. MPJ and ankle joint stiffness measurement is still largely depended on manual skills as current devices do not have good control on alignment, angular joint speed and displacement during measurement. Therefore, this study introduces an innovative dynamometer and protocol procedures for MPJ and ankle Joint torque measurement with precise and reliable foot alignment, angular joint speed and displacement control. Within-day and between-day test-retest experiments on MPJ and ankle joint torque measurement were conducted on ten and nine healthy male subjects respectively. The mean peak torques of MPJ and ankle joint of between-day and within-day measurement were 1.50±0.38Nm/deg and 1.19±0.34Nm/deg. The corresponding torques of the ankle joint were 8.24±2.20Nm/deg and 7.90±3.18Nm/deg respectively. Intraclass-correlation coefficients (ICC) of averaged peak torque of both joints of between-day and within-day test-retest experiments were ranging from 0.91 to 0.96, indicating the innovative device is systematic and reliable for the measurements and can be used for multiple scientific and clinical purposes.

Factors affecting the range of motion of the ankle and first metatarsophalangeal joints in patients undergoing hemodialysis who walk daily

[Purpose] Increased plantar pressure during walking is a risk factor for foot ulcers because of reduced range of motion at the ankle and first metatarsophalangeal joints. However, the range of motion in patients undergoing hemodialysis has not yet been determined. A cross-sectional study was performed to investigate the factors affecting the range of motion of the ankle and first metatarsophalangeal joints in patients undergoing hemodialysis who walk daily. [Subjects and Methods] Seventy feet of 35 patients receiving hemodialysis therapy were examined. Measurements included the passive range of motion of plantar flexion and dorsiflexion of the ankle joint, and flexion and extension of the first metatarsophalangeal joint. [Results] Hemodialysis duration was not associated with ankle and first metatarsophalangeal joint range of motion in patients undergoing hemodialysis. Diabetes duration was significantly associated with limited ankle joint mobility. Finally, blood hemoglobin levels, body mass index, and age were associated with first metatarsophalangeal joint range of motion. [Conclusion] The present study identified age, diabetes, and decreased physical activity, but not hemodialysis duration, to be risk factors for limited joint mobility of the ankle and first metatarsophalangeal joints in patients undergoing hemodialysis.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Predictors of barefoot plantar pressure during walking in patients with diabetes, peripheral neuropathy and a history of ulceration

Objective

Elevated dynamic plantar foot pressures significantly increase the risk of foot ulceration in diabetes mellitus. The aim was to determine which factors predict plantar pressures in a population of diabetic patients who are at high-risk of foot ulceration.

Methods

Patients with diabetes, peripheral neuropathy and a history of ulceration were eligible for inclusion in this cross sectional study. Demographic data, foot structure and function, and disease-related factors were recorded and used as potential predictor variables in the analyses. Barefoot peak pressures during walking were calculated for the heel, midfoot, forefoot, lesser toes, and hallux regions. Potential predictors were investigated using multivariate linear regression analyses. 167 participants with mean age of 63 years contributed 329 feet to the analyses.

Results

The regression models were able to predict between 6% (heel) and 41% (midfoot) of the variation in peak plantar pressures. The largest contributing factor in the heel model was glycosylated haemoglobin concentration, in the midfoot Charcot deformity, in the forefoot prominent metatarsal heads, in the lesser toes hammer toe deformity and in the hallux previous ulceration. Variables with local effects (e.g. foot deformity) were stronger predictors of plantar pressure than global features (e.g. body mass, age, gender, or diabetes duration).

Conclusion

The presence of local deformity was the largest contributing factor to barefoot dynamic plantar pressure in high-risk diabetic patients and should therefore be adequately managed to reduce plantar pressure and ulcer risk. However, a significant amount of variance is unexplained by the models, which advocates the quantitative measurement of plantar pressures in the clinical risk assessment of the patient.

Kinematics and kinetics of single-limb heel rise in diabetes related medial column foot deformity

BACKGROUND

Diabetes-related medial column foot deformities contribute to high plantar pressure, joint instability, ulceration and amputation. Impaired foot function may be an early indicator of foot structural incompetence and contribute to deformity progression. This study examines the ability of single-limb heel rise multi-segmental kinematics and kinetics to identify midfoot and hindfoot dysfunction in those with diabetes-related medial column foot deformity.

METHODS

Single-limb heel rise foot kinematics and kinetics were examined in adults with diabetes mellitus and peripheral neuropathy with and without medial column foot deformity and age-, weight-matched controls.

FINDINGS

Hindfoot relative to shank plantarflexion, peak and excursion, were reduced in both diabetes groups compared to controls (P<0.017). Controls' initial forefoot relative to hindfoot position was plantarflexed 31° and plantarflexed an additional 13° during heel rise. The initial forefoot relative to hindfoot position for the diabetes group without deformity was similarly plantarflexed as controls (34°) while the diabetes deformity group was less plantarflexed (lower arch position: 23°, P<0.017). During the heel rise task both diabetes groups demonstrated less ability to plantarflex the forefoot relative to the hindfoot compared to controls (2 and 5° respectively, P<0.017). Ankle plantarflexion power was reduced in the diabetes deformity group compared to controls (P<0.017).

INTERPRETATION

The single-limb heel rise task identified movement dysfunction in those with diabetes mellitus and peripheral neuropathy. Failure to plantarflex the forefoot relative to hindfoot may compromise midfoot joint stability and increase the risk of injury and arch collapse.

Radiographic-directed local coordinate systems critical in kinematic analysis of walking in diabetes-related medial column foot deformity

Diabetic foot deformity onset and progression maybe associated with abnormal foot and ankle motion. The modified Oxford multi-segmental foot model allows kinematic assessment of inter-segmental foot motion. However, there are insufficient anatomical landmarks to accurately representation the alignment of the hindfoot and forefoot segments during model construction. This is most notable for the sagittal plane which is referenced parallel to the floor, allowing comparison of inter-segmental excursion but not capturing important sagittal hind-to-forefoot deformity associated with diabetic foot disease and can potentially underestimate true kinematic differences. The purpose of the study was to compare walking kinematics using local coordinate systems derived from the modified Oxford model and the radiographic directed model which incorporated individual calcaneal and 1st metatarsal declination pitch angles for the hindfoot and forefoot. We studied twelve participants in each of the following groups: (1) diabetes mellitus, peripheral neuropathy and medial column foot deformity (DMPN+), (2) DMPN without medial column deformity (DMPN-) and (3) age- and weight-match controls. The modified Oxford model coordinate system did not identify differences between groups in the initial, peak, final, or excursion hindfoot relative to shank or forefoot relative to hindfoot dorsiflexion/plantarflexion during walking. The radiographic coordinate system identified the DMPN+ group to have an initial, peak and final position of the forefoot relative to hindfoot that was more dorsiflexed (lower arch phenotype) than the DMPN- group (p<.05). Use of radiographic alignment in kinematic modeling of those with foot deformity reveals segmental motion occurring upon alignment indicative of a lower arch.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Interventions for increasing ankle joint dorsiflexion: a systematic review and meta-analysis

BACKGROUND

Ankle joint equinus, or restricted dorsiflexion range of motion (ROM), has been linked to a range of pathologies of relevance to clinical practitioners. This systematic review and meta-analysis investigated the effects of conservative interventions on ankle joint ROM in healthy individuals and athletic populations.

METHODS

Keyword searches of Embase, Medline, Cochrane and CINAHL databases were performed with the final search being run in August 2013. Studies were eligible for inclusion if they assessed the effect of a non-surgical intervention on ankle joint dorsiflexion in healthy populations. Studies were quality rated using a standard quality assessment scale. Standardised mean differences (SMDs) and 95% confidence intervals (CIs) were calculated and results were pooled where study methods were homogenous.

RESULTS

Twenty-three studies met eligibility criteria, with a total of 734 study participants. Results suggest that there is some evidence to support the efficacy of static stretching alone (SMDs: range 0.70 to 1.69) and static stretching in combination with ultrasound (SMDs: range 0.91 to 0.95), diathermy (SMD 1.12), diathermy and ice (SMD 1.16), heel raise exercises (SMDs: range 0.70 to 0.77), superficial moist heat (SMDs: range 0.65 to 0.84) and warm up (SMD 0.87) in improving ankle joint dorsiflexion ROM.

CONCLUSIONS

Some evidence exists to support the efficacy of stretching alone and stretching in combination with other therapies in increasing ankle joint ROM in healthy individuals. There is a paucity of quality evidence to support the efficacy of other non-surgical interventions, thus further research in this area is warranted.

Biomechanical characteristics of peripheral diabetic neuropathy: A systematic review and meta-analysis of findings from the gait cycle, muscle activity and dynamic barefoot plantar pressure

BACKGROUND

Diabetic peripheral neuropathy is an important cause of foot ulceration and limb loss. This systematic review and meta-analysis investigated the effect of diabetic peripheral neuropathy on gait, dynamic electromyography and dynamic plantar pressures.

METHODS

Electronic databases were searched systematically for articles reporting the effect of diabetic peripheral neuropathy on gait, dynamic electromyography and plantar pressures. Searches were restricted to articles published between January 2000 and April 2012. Outcome measures assessed included spatiotemporal parameters, lower limb kinematics, kinetics, muscle activation and plantar pressure. Meta-analyses were carried out on all outcome measures reported by ≥3 studies.

FINDINGS

Sixteen studies were included consisting of 382 neuropathy participants, 216 diabetes controls without neuropathy and 207 healthy controls. Meta-analysis was performed on 11 gait variables. A high level of heterogeneity was noted between studies. Meta-analysis results suggested a longer stance time and moderately higher plantar pressures in diabetic peripheral neuropathy patients at the rearfoot, midfoot and forefoot compared to controls. Systematic review of studies suggested potential differences in the biomechanical characteristics (kinematics, kinetics, EMG) of diabetic neuropathy patients. However these findings were inconsistent and limited by small sample sizes.

INTERPRETATION

Current evidence suggests that patients with diabetic peripheral neuropathy have elevated plantar pressures and occupy a longer duration of time in the stance-phase during gait. Firm conclusions are hampered by the heterogeneity and small sample sizes of available studies.

Gait characteristics of people with diabetes-related peripheral neuropathy, with and without a history of ulceration

Biomechanical alterations in diabetes are believed to contribute to plantar neuropathic ulceration. This exploratory study documents clinical measures of flexibility and strength, alongside three-dimensional biomechanical gait data of the lower limb, in 10 patients with a history of neuropathic ulceration (DNU; n=10). Comparative data is presented from age and gender matched groups with; diabetes peripheral neuropathy and no ulcer history (DWN; n=10), diabetes and no peripheral neuropathy (DNN; n=10) and a non-diabetes reference group (NOND; n=10). Biomechanical data were collected at a comfortable walking speed with a Vicon motion analysis system. Clinical measures showed a non-significant trend toward decreased static range of motion at the ankle and first metatarsophalangeal joints, with worsening neuropathy status. Of the diabetes groups, knee and ankle strength was significantly lower in those with an ulcer history (p=0.01-0.03), with the exception of knee extension. In the DNU group, walking speed was on average 0.17 ms slower compared to NOND (p=0.04). The DNU group demonstrated a lower range of motion than NOND at the: hips (frontal plane, by 25%: p=0.03); hips and knees (transverse plane, 31%: p=0.01 and 32%: p<0.01); ankles (sagittal plane, 22%: p<0.01) and first metatarsophalangeal joints (sagittal plane, 32%: p=0.01), with less foot rotation (24%: p=0.04). Kinetic alterations in DNU included lower: ankle maximum power (21%: p=0.03) and vertical ground reaction force 2nd peak (6%: p<0.01). The study findings identified gait alterations in people with clinically severe peripheral neuropathy and related plantar foot ulcer history. Further research is needed to explore potential casual pathways.

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.

Association of limited joint mobility and increased plantar hardness in diabetic foot ulceration in north Asian Indian: a preliminary study

The aim of this article is to investigate the association of limited joint mobility and foot sole hardness in north Asian Indian type 2 diabetic patients. Limited joint mobility and hardness of the foot sole were measured for 39 subjects attending the AIIMS Endocrinology & Metabolism Clinic. The total subject divided into three groups: 13 control subjects (nondiabetic), 13 diabetic patients without neuropathy and 13 diabetic neuropathy patients. Neuropathy status was assessed using 10 gm Semen's Weinstein monofilament. Joint mobility parameters, such as ankle dorsiflexion/plantar flexion and metatarsophalangeal-1 dorsiflexion/plantar flexion, are measured using a goniometer. Foot sole hardness was measured using a durometer or shore meter. We found that diabetic patients with a neuropathic foot had significantly reduced joint mobility and increased foot sole hardness, placing them at risk for subsequent ulceration. Metatarsophalangeal-1 dorsiflexion/plantar flexion of both feet of diabetic patients had significant correlation (at p < 0.05, p < 0.001, p < 0.001 level) over age and body mass index. Also ankle plantar flexion/dorsiflexion and metatarsophalangeal-1 dorsiflexion/plantar flexion has a significant correlations (at p < 0.01, p < 0.05, p < 0.001, p < 0.001 level) with foot sole hardness in both feet of diabetic neuropathy subjects. Also linear regression analysis showed that duration of diabetes was significantly associated with the joint mobility parameters. In this study we conclude that joint mobility had reduced further if neuropathy and increased foot sole hardness coexisted owing to high plantar pressures. Hence, both limited joint mobility and increased foot sole hardness appears to be important determinants of foot sole ulceration in diabetic neuropathic subject.

The effect of foot structure on 1st metatarsophalangeal joint flexibility and hallucal loading

The purpose of our study was to examine 1st metatarsophalangeal (MTP) joint motion and flexibility and plantar loads in individuals with high, normal and low arch foot structures. Asymptomatic individuals (n=61), with high, normal and low arches participated in this study. Foot structure was quantified using malleolar valgus index (MVI) and arch height index (AHI). First MTP joint flexibility was measured using a specially constructed jig. Peak pressure under the hallux, 1st and 2nd metatarsals during walking was assessed using a pedobarograph. A one-way ANOVA with Bonferroni-adjusted post hoc comparisons was used to assess between-group differences in MVI, AHI, early and late 1st MTP joint flexibility in sitting and standing, peak dorsiflexion (DF), and peak pressure under the hallux, 1st and 2nd metatarsals. Stepwise linear regression was used to identify predictors of hallucal loading. Significant between-group differences were found in MVI (F(2,56)=15.4, p<0.01), 1st MTP late flexibility in sitting (F(2,57)=3.7, p=0.03), and standing (F(2,57)=3.7, p=0.03). Post hoc comparisons demonstrated that 1st MTP late flexibility in sitting was significantly higher in individuals with low arch compared to high arch structure, and that 1st MTP late flexibility in standing was significantly higher in individuals with low arch compared to normal arch structure. Stepwise regression analysis indicated that MVI and 1st MTP joint early flexibility in sitting explain about 20% of the variance in hallucal peak pressure. Our results provide objective evidence indicating that individuals with low arches show increased 1st MTP joint late flexibility compared to individuals with normal arch structure, and that hindfoot alignment and 1st MTP joint flexibility affect hallucal loading.

The effects of walking speed on forefoot, hindfoot and ankle joint motion

BACKGROUND

Foot and ankle joint kinematic differences have been identified between healthy subjects and subjects with various pathologies suffering from foot and ankle impairments. Changes in temporal factors such as walking speed and double stance time are also found in these pathological conditions. As such, in theory, these factors would also influence the kinematics and hence make it difficult to ascertain the effects of the disease on the kinematics. The aim of this study was to analyse foot and ankle kinematics from gait recordings of healthy subjects walking at comfortable and slower speeds.

METHODS

Gait patterns of 14 healthy subjects were recorded. The subjects were first asked to walk at a comfortable speed and then at predefined speeds of 75% and 50% of their comfortable walking speed respectively. Temporal variables were calculated. Foot and ankle joint kinematics were determined from marker-recordings.

FINDINGS

The subjects walked at mean velocities of 1.28 m/s, 0.97 m/s and 0.65 m/s. With decreasing walking speed the minimum tibio-talar plantar-flexion and maximum hallux dorsi-flexion at toe-off decreased significantly between 3 degrees and 9 degrees. The minimum medial arch at toe-off and minimum midfoot supination at mid-stance were significantly affected by the walking speed. The corresponding individual session differences were small (1 degrees -2 degrees), but the reliability was high and hence the differences were considered clinically relevant.

INTERPRETATION

Walking speed significantly affected foot and ankle kinematics. Studies aiming to improve the understanding of the effects of foot and ankle pathologies on foot and ankle kinematics should take the walking speed into account.

Diabetic foot biomechanics and gait dysfunction

BACKGROUND

Diabetic foot complications represent significant morbidity and precede most of the lower extremity amputations performed. Peripheral neuropathy is a frequent complication of diabetes shown to affect gait. Glycosylation of soft tissues can also affect gait. The purpose of this review article is to highlight the changes in gait for persons with diabetes and highlight the effects of glycosylation on soft tissues at the foot-ground interface.

METHODS

PubMed, the Cochrane Library, and EBSCOhost on-line databases were searched for articles pertaining to diabetes and gait. Bibliographies from relevant manuscripts were also searched.

FINDINGS

Patients with diabetes frequently exhibit a conservative gait strategy where there is slower walking speed, wider base of gait, and prolonged double support time. Glycosylation affects are observed in the lower extremities. Initially, skin thickness decreases and skin hardness increases; tendons thicken; muscles atrophy and exhibit activation delays; bones become less dense; joints have limited mobility; and fat pads are less thick, demonstrate fibrotic atrophy, migrate distally, and may be stiffer.

INTERPRETATION

In conclusion, there do appear to be gait changes in patients with diabetes. These changes, coupled with local soft tissue changes from advanced glycosylated end products, also alter a patient's gait, putting them at risk of foot ulceration. Better elucidation of these changes throughout the entire spectrum of diabetes disease can help design better treatments and potentially reduce the unnecessarily high prevalence of foot ulcers and amputation.

Plantar pressure distribution patterns during gait in diabetic neuropathy patients with a history of foot ulcers

OBJECTIVE

To investigate and compare the influence of a previous history of foot ulcers on plantar pressure variables during gait of patients with diabetic neuropathy.

INTRODUCTION

Foot ulcers may be an indicator of worsening diabetic neuropathy. However, the behavior of plantar pressure patterns over time and during the progression of neuropathy, especially in patients who have a clinical history of foot ulcers, is still unclear.

METHODS

Subjects were divided into the following groups: control group, 20 subjects; diabetic neuropathy patients without foot ulcers, 17 subjects; and diabetic neuropathy patients with at least one healed foot ulcer within the last year, 10 subjects. Plantar pressure distribution was recorded during barefoot gait using the Pedar-X system.

RESULTS

Neuropathic subjects from both the diabetic neuropathy and DNU groups showed higher plantar pressure than control subjects. At midfoot, the peak pressure was significantly different among all groups: control group (139.4+/-76.4 kPa), diabetic neuropathy (205.3+/-118.6 kPa) and DNU (290.7+/-151.5 kPa) (p=0.008). The pressure-time integral was significantly higher in the ulcerated neuropathic groups at midfoot (CG: 37.3+/-11.4 kPa.s; DN: 43.3+/-9.1 kPa.s; DNU: 68.7+/-36.5 kPa.s; p=0.002) and rearfoot (CG: 83.3+/-21.2 kPa.s; DN: 94.9+/-29.4 kPa.s; DNU: 102.5+/-37.9 kPa.s; p=0.048).

CONCLUSION

A history of foot ulcers in the clinical history of diabetic neuropathy subjects influenced plantar pressure distribution, resulting in an increased load under the midfoot and rearfoot and an increase in the variability of plantar pressure during barefoot gait. The progression of diabetic neuropathy was not found to influence plantar pressure distribution.

Role of ankle mobility in foot rollover during gait in individuals with diabetic neuropathy

BACKGROUND

The purpose of this study was to investigate the ankle range of motion during neuropathic gait and its influence on plantar pressure distribution in two phases during stance: at heel-strike and at push-off.

METHODS

Thirty-one adults participated in this study (control group, n=16; diabetic neuropathic group, n=15). Dynamic ankle range of motion (electrogoniometer) and plantar pressures (PEDAR-X system) were acquired synchronously during walking. Plantar pressures were evaluated at rearfoot, midfoot and forefoot during the two phases of stance. General linear model repeated measures analysis of variance was applied to investigate relationships between groups, areas and stance phases.

FINDINGS

Diabetic neuropathy patients walked using a smaller ankle range of motion in stance phase and smaller ankle flexion at heel-strike (P=0.0005). Peak pressure and pressure-time integral values were higher in the diabetic group in the midfoot at push-off phase when compared to heel-strike phase. On the other hand, the control group showed similar values of peak pressure in midfoot during both stance phases.

INTERPRETATION

The ankle mobility reduction observed could be associated to altered plantar pressure distribution observed in neuropathic subjects. Results demonstrated that midfoot and forefoot play a different role in subjects with neuropathy by receiving higher loads at push-off phase that are probably due to smaller ankle flexion at stance phase. This may explain the higher loads in anterior areas of the foot observed in diabetic neuropathy subjects and confirm an inadequate foot rollover associated to the smaller ankle range of motion at the heel-strike phase.

Effect of turf toe on foot contact pressures in professional American football players

BACKGROUND

The relationship between turf toe and plantar foot pressures has not been extensively studied. Two hypotheses were tested in a cohort of professional American football players: first, that a history of turf toe is associated with increased peak hallucal and first metatarsophalangeal (MTP) plantar pressures; second, that decreased range of motion (ROM) of the first MTP correlates with increased peak hallucal and first MTP plantar pressures.

MATERIALS AND METHODS

Forty-four athletes from one National Football League (NFL) team were screened for a history of turf toe during preseason training. Dorsal passive MTP ROM and dynamic plantar pressures were measured in both feet of each player. Anatomical masking was used to assess peak pressure at the first MTP and hallux.

RESULTS

First MTP dorsiflexion was significantly lower in halluces with a history of turf toe (40.6 +/- 15.1 degrees versus 48.4 +/- 12.8 degrees, p = 0.04). Peak hallucal pressures were higher in athletes with turf toe (535 +/- 288 kPa versus 414 +/- 202 kPa, p = 0.05) even after normalizing for athlete body mass index (p = 0.0003). Peak MTP pressure was not significantly different between the two groups tested. First MTP dorsiflexion did not correlate with peak hallucal or first MTP pressures.

CONCLUSION

This study showed that turf toe is associated with decreased MTP motion. In addition, increased peak hallucal pressures were found. Further study is warranted to determine whether these pressures correlate with the severity of symptoms or progression of turf toe to first MTP arthritis.

Plantar pressure distribution patterns during gait in diabetic neuropathy patients with a history of foot ulcers

OBJECTIVE

To investigate and compare the influence of a previous history of foot ulcers on plantar pressure variables during gait of patients with diabetic neuropathy.

INTRODUCTION

Foot ulcers may be an indicator of worsening diabetic neuropathy. However, the behavior of plantar pressure patterns over time and during the progression of neuropathy, especially in patients who have a clinical history of foot ulcers, is still unclear.

METHODS

Subjects were divided into the following groups: control group, 20 subjects; diabetic neuropathy patients without foot ulcers, 17 subjects; and diabetic neuropathy patients with at least one healed foot ulcer within the last year, 10 subjects. Plantar pressure distribution was recorded during barefoot gait using the Pedar-X system.

RESULTS

Neuropathic subjects from both the diabetic neuropathy and DNU groups showed higher plantar pressure than control subjects. At midfoot, the peak pressure was significantly different among all groups: control group (139.4+/-76.4 kPa), diabetic neuropathy (205.3+/-118.6 kPa) and DNU (290.7+/-151.5 kPa) (p=0.008). The pressure-time integral was significantly higher in the ulcerated neuropathic groups at midfoot (CG: 37.3+/-11.4 kPa.s; DN: 43.3+/-9.1 kPa.s; DNU: 68.7+/-36.5 kPa.s; p=0.002) and rearfoot (CG: 83.3+/-21.2 kPa.s; DN: 94.9+/-29.4 kPa.s; DNU: 102.5+/-37.9 kPa.s; p=0.048).

CONCLUSION

A history of foot ulcers in the clinical history of diabetic neuropathy subjects influenced plantar pressure distribution, resulting in an increased load under the midfoot and rearfoot and an increase in the variability of plantar pressure during barefoot gait. The progression of diabetic neuropathy was not found to influence plantar pressure distribution.

Prediction of peak pressure from clinical and radiological measurements in patients with diabetes

BACKGROUND

Various structural and functional factors of foot function have been associated with high local plantar pressures. The therapist focuses on these features which are thought to be responsible for plantar ulceration in patients with diabetes. Risk assessment of the diabetic foot would be made easier if locally elevated plantar pressure could be indicated with a minimum set of clinical measures.

METHODS

Ninety three patients were evaluated through vascular, orthopaedic, neurological and radiological assessment. A pressure platform was used to quantify the barefoot peak pressure for six forefoot regions: big toe (BT) and metatarsals one (MT-1) to five (MT-5). Stepwise regression modelling was performed to determine which set of the clinical and radiological measures explained most variability in local barefoot plantar peak pressure in each of the six forefoot regions. Comprehensive models were computed with independent variables from the clinical and radiological measurements. The difference between the actual plantar pressure and the predicted value was examined through Bland-Altman analysis.

RESULTS

Forefoot pressures were significant higher in patients with neuropathy, compared to patients without neuropathy for the whole forefoot, the MT-1 region and the MT-5 region (respectively 138 kPa, 173 kPa and 88 kPa higher: mean difference). The clinical models explained up to 39 percent of the variance in local peak pressures. Callus formation and toe deformity were identified as relevant clinical predictors for all forefoot regions. Regression models with radiological variables explained about 26 percent of the variance in local peak pressures. For most regions the combination of clinical and radiological variables resulted in a higher explained variance. The Bland and Altman analysis showed a major discrepancy between the predicted and the actual peak pressure values.

CONCLUSION

At best, clinical and radiological measurements could only explain about 34 percent of the variance in local barefoot peak pressure in this population of diabetic patients. The prediction models constructed with linear regression are not useful in clinical practice because of considerable underestimation of high plantar pressure values. Identification of elevated plantar pressure without equipment for quantification of plantar pressure is inadequate. The use of quantitative plantar pressure measurement for diabetic foot screening is therefore advocated.