Diabetic Neuropathic Subjects Research Articles

The insole materials influence the plantar pressure distributions in diabetic foot with neuropathy during different walking activities

BackgroundAbnormal peak plantar pressure in neuropathic diabetic foot during walking activities is well managed through the use of appropriate design and material selection for the fabrication of custom made insoles (CMI). The redistribution of plantar pressure is possible by selecting an appropriate material for the fabrication of CMI. The walking activities may alter the plantar pressure distribution; which may differ while using CMI with different materials. ObjectiveThe objective of the study was to evaluate the effectiveness of CMI’s materials on plantar pressure distribution during different walking activities, in diabetic feet with neuropathy. MethodsThe study was conducted on sixteen diabetic neuropathic subjects. The subjects were provided with two types of CMI; CMI-A (Plastazote® and microcellular rubber) and CMI-B (Multifoam, Plastazote® and microcellular rubber). Maximum peak plantar pressure and plantar pressure distribution were determined by Pedar-X® sensor insole during level walking, ramp walking and stair walking. ResultsThe CMI-B lessened the maximum peak plantar pressure from the forefoot throughout the walking activities compared to CMI-A. The contact area was observed as lower using CMI-A compared to CMI-B, while performing walking activities. ConclusionCMI-B, with multifoam as an additional top layer, provided more effective peak plantar pressure reduction at forefoot and it had better plantar pressure distribution compared to CMI-A during level walking and ramp ascending in diabetic foot with neuropathy.

Validation of plantar pressure simulations using finite and discrete element modelling in healthy and diabetic subjects

Plantar pressure simulation driven by integrated 3D motion capture data, using both a finite element and a discrete element model, is compared for ten healthy and ten diabetic neuropathic subjects. The simulated peak pressure deviated on average between 16.7 and 34.2% from the measured peak pressure. The error in the position of the peak pressure was on average smaller than 4.2 cm. No method was more accurate than the other although statistical differences were found between them. Both techniques are thus complementary and useful tools to better understand the alteration of diabetic foot biomechanics during gait.

The role of muscle forces on foot internal stresses and plantar pressure distribution: differences between healthy and diabetic neuropathic subjects

Tobacco/nicotine dependence has a significant heritable component. Genome-wide association studies have associated the single nucleotide polymorphisms (SNPs) rs578776, rs16969968, rs6474412, rs3733829 and rs4105144 with nicotine dependence in Western European populations. We examined whether these SNPs influence nicotine dependence and successful treatment of tobacco dependence in the Czech middle-European population.Variants were analysed by PCR-RFLP or by TaqMan assay in 807 adult heavy tobacco-dependent smokers – patients of the Centre for Treatment of Tobacco Dependence (Prague) as well as 1,362 self-reported non-smokers.Except for rs3733829, association with tobacco dependence was confirmed for all other genetic variants. In agreement with previous studies, the strongest determinant of tobacco dependence was rs16969968 with OR (95%CI) 1.32 (1.08–1.62) for A allele carriers vs. GG comparison (P = 0.003). In contrast, none of the analysed variants reached significance with respect to a 1-year course of successful tobacco dependence treatment (all P over 0.18) in a subset of 525 patients.We confirmed the association between variants within genes that code nicotinic-acetylcholine receptors (-A3, -A5 and -B3), CYP2A6/B6 and tobacco dependence development in the Czech population. The success of the tobacco dependence treatment was not influenced by the analysed SNPs.

GAIT ANALYSIS DRIVEN 2D FINITE ELEMENT MODEL OF THE NEUROPATHIC HINDFOOT

The diabetic foot is one of the most serious complications of diabetes mellitus and it can lead to foot ulcerations and amputations. Finite element analysis quantifies the loads developed in the different anatomical structures and describes how these affect foot tissue during foot–floor interaction. This approach for the diabetic subjects’ foot could provide valuable information in the process of plantar orthosis fabrication and fit. The purpose of this study was to develop two finite element models of the hindfoot, of healthy and diabetic neuropathic subjects. These models accounts for in vivo kinematics, kinetics, plantar pressure (PP) data and magnetic resonance images. These were acquired during gait analysis on 10 diabetic neuropathics and 10 healthy subjects. Validity of the models has been assessed through comparison between the peak PPs of simulated and experimental data: root mean square error (RMSE) in percentage of the experimental peak value was evaluated. Two different finite elements analysis were performed: subject-specific simulations in terms of both geometry and gait analysis, and by adopting the complete gait analysis dataset as boundary conditions. Model predicted plantar pressures were in good agreement with those experimentally measured. Best agreement was obtained in the subject-specific case (RMSE of 13%).

Influência da neuropatia diabética no comportamento de respostas biomecânicas e sensorials no andar em esteira rolante

Biomechanical investigation of the human movement has been bringing important discussions about the musculoskeletal system functions and the control of movement. The human walking is one of the most studied motor behaviors and its mechanical aspects contribute to characterize, identify, and intervene in pathological conditions. Dynamic, kinematic, and electromyographic analyses of pathological gait can significantly help the comprehension of the control mechanism of gait and its compensatory alterations. These analyses can also contribute to therapeutic and preventive interventions in patients whose walking behavior is altered due to some disease that accomplish the neuromotor system. In the present study, we described and interpreted self-cadence walking in a treadmill of neuropathic diabetic subjects under biomechanical considerations, such as dynamic, temporal, spatial, and electromyographic analysis during stance phase. We also studied sensorial and motor aspects in order to characterize the neuropathic and control subjects. The somatossensorial responses and pain tolerance threshold in the neuropathic subjects were significantly higher and considered away from the normal patterns. The self-cadence and the treadmill velocity were significantly lower in neuropathic gait. Single and double stance time, stride and step length were significantly higher during neuropathic gait. The neuropathic subjects showed lower vertical force peaks and lower deflections of vertical force and those findings were secondary consequences of the conservative strategy of lowering the gait velocity adopted by the neuropathic in order to reach a more stable locomotor pattern. The electromyographic responses of the thigh and leg muscles in neuropathic subjects showed lower magnitudes and were delayed paring to the normal recruitment pattern, specially the anteriortibialis muscle right and left. These findings lead us to conclude that probably central and/or peripheral control mechanisms of the gait of neuropathic diabetic patients are altered due to somatossensorial and motor deficits. The mechanism of load reduction during walking was considered inefficient because of the activation delay of the lateral vastus and anterior tibialis muscles. We conclude that the peripheral diabetic neuropathy damages not only somatossensorial and motor sources but also intrinsic mechanisms of motor control leading to alterations in the ankle efficiency in gait. This resulting distal inefficiency compromises some of the principal requirements to gait, which are progression and balance.

Muscle activation patterns related to diabetic neuropathy in elderly subjects: A Functional Reach Test study

BackgroundThis study was designed to assess, in healthy elderly, non-neuropathic and neuropathic diabetic subjects, the activation patterns of the main muscles involved in the Functional Reach Test, a well-recognized method to identify elderly subjects at risk of balance impairments. MethodsSurface electromyographic analysis of Sternocleidomastoideus, Rectus Abdominis, Erectores Spinae at L4 level, Rectus Femoris, Hamstrings, Tibialis Anterior and Soleus was performed in 10 healthy, 10 diabetic non-neuropathic and 10 diabetic neuropathic subjects. FindingsResults showed that in every group the first motor is Tibialis Anterior, that is recruited before the start of the test. An earlier activation of Tibialis Anterior (P<0.05) was detected in diabetic neuropathic (ON at −24% of the test period), compared with healthy (−11%) and diabetic non-neuropathic (−13%) groups. A significant earlier activation of Sternocleidomastoideus and Rectus Abdominis was found in diabetic neuropathic group, only with respect to healthy subjects. No significant difference was found in Rectus Femoris, Soleus, Hamstrings an Erectores Spinae onset among the three groups. InterpretationResults suggest a trend of diabetic neuropathic patients in earlier anticipation of the activation of the anterior body-muscles. In particular, the earlier onset of Tibialis Anterior is likely to be performed to adjust the movement timing and to compensate for the delay in the recruitment of the motor units. This anticipation might be involved in the altered postural control with increased balance impairment detected in diabetic neuropathic patients, and thereby it might also be proposed as an index of neuropathy, evidenced in a simple and non-invasive manner.

Prevalence of standing plantar pressure distribution variation in north Asian Indian patients with diabetes mellitus: A study to understand ulcer formation

Diabetes Mellitus is a disorder of metabolism. Foot problems are common in diabetes and altered plantar pressures distribution may lead to ulceration in people with Diabetes Mellitus. Therefore the aim of this study was to investigate standing plantar pressure distribution variations in north Asian Indian diabetes mellitus subjects and its association with duration of diabetes. Thirty three subjects with age range from 40 to 75 years are recruited from AIIMS Endocrinology & metabolism lab Delhi, India and divided into three groups: 11 control subjects (non-diabetic), 11 diabetic subjects without neuropathy (DNN) and II diabetic subjects with neuropathy (DN). Neuropathy status was assessed by measuring loss of protective sensation to 10 gm Semen's Weinstein monofilament. Plantar pressure distributions parameter-Power ratio (PR) was measured during barefoot standing using portable PedoPowerGraph and results are analyzed using one way analysis of variance to detect significant difference between the groups. We found significant (p < 0.05; p < 0.01) difference in PR value between DN and CG groups in fore foot and hind foot but no significant (p > 0.05) difference in PR value was found between DNN and CG groups in the foot. As compared to DNN, DN group have maximum PR variations in the fore foot. Plantar pressure distribution parameter-PR was higher with longer duration of diabetes among type 2 diabetes subjects. In this study we conclude that plantar pressure distribution parameter-PR was able to distinguish the DN groups from the CG group in hind and fore foot during standing. Increased forefoot PR value is prevalent in the diabetic neuropathic subjects and may be responsible for the occurrence of foot sole ulcers but additional prospective studies are needed. In the future we will investigate the plantar pressure distribution parameter-PR variations in diabetes with obese and osteoarthritis subject.

Effect of usual versus therapeutic shoes in the decrease of plantar pressure in diabetic neuropathic subjects

High plantar pressures have been cited as one of the main causes of ulcers in diabetic feet ( Veves et al., 1992 Veves et al. Diabetologia. 1992; 35: 660-663 Crossref PubMed Scopus (558) Google Scholar ). Also, shod condition reduces peak plantar pressure relative to barefoot condition ( Burnfield et al., 2004 Burnfield et al. Clinical Biomechanics. 2004; 19: 78-84 Abstract Full Text Full Text PDF PubMed Scopus (234) Google Scholar ). Furthermore, therapeutic footwear has been recommended to diabetic patients as an attempt to prevent ulceration. However, the question regarding their effectiveness still remains, since Reiber et al., 2002 Reiber et al. JAMA. 2002; 287: 2552-2558 Crossref PubMed Scopus (178) Google Scholar found no difference between usual and therapeutic footwear in patients with foot ulcer history. Therefore, the aim of this study was to evaluate the effect of therapeutic footwear in the decrease of the peak plantar pressure in diabetic neuropathic feet during gait. We hypothesized that subjects who wear therapeutic footwear present lower plantar pressure than subjects who wear usual shoes.

Lower longitudinal plantar arch in diabetic neuropathy: Effects in plantar pressure during gait

Diabetic neuropathy may promote higher peak pressures during gait probably due to bone prominences, joint deformities and alterations in the architecture of the longitudinal plantar arch. The arch index (Cavanagh and Rodgers, 1987) is a potential predictor of plantar peak pressure in midfoot (Morag et al., 1999; Menz et al., 2005). Therefore, we aimed at investigating if flat feet in neuropathic diabetic subjects influences plantar pressure distribution.

SARCOPENIA

Purpose/Hypothesis: Sarcopenia is an age-related decline in skeletal muscle mass and strength and a major cause of decreased physical function contributing to frailty in the elderly. Sarcopenia is a prominent impairment in a variety of chronic diseases seen by physical therapists. The purpose of this study was to determine the impact of lower extremity (LE) muscle strength (sarcopenia) and its relationship to physical frailty in diabetic neuropathic (DN), elderly obese (EO), and elderly non-obese (EN) individuals. Subjects: Fifty-three DN subjects (37 men, 16 women; age 54±10 years, mean BMI= 32 ± 6; duration of DM 16±11years); 29 EO subjects (12 men, 17 women, age 70±4 years, BMI = 38±5); and 95 EN subjects (25 men, 70 women, age 80±7 years, BMI = 25±6) were studied. Materials/Methods: All impairment measurements were collected during a single session. The 9-item physical performance test (PPT) was used as an objective assessment of physical frailty. Peak torque of the quadriceps, hamstrings, plantar flexors, and dorsiflexors was assessed at 3 speeds with an isokinetic dynamometer to determine muscle strength and severity of sarcopenia. Mean ± sd were calculated for each cohort and compared using oneway ANOVA. Univariate and multivariate (age, BMI, and peak torque of the quadriceps, hamstring, dorsiflexors, and plantarflexors) regression analyses were performed for the entire sample (pooled) and in each cohort separately to determine the best predictors of physical frailty (total PPT score). Results: The mean PPT score was 26±7 in the DN group, 27±3 in the EO group and 22±6 in the EN group. (F=15.3, p<0.00). Regression analyses demonstrated age, BMI, quadriceps and dorsiflexor strength best predict PPT in DN group (r2=0.501, p<0.03), while quadriceps, dorsiflexor and plantar flexor strength best predict PPT in EN group (r2=0.304, p<0.04). In the EO group, BMI best predicts PPT (r2=0.146, p<0.05), while strength of LE muscle groups did not predict total PPT score. Conclusions: Sarcopenia is a common pathogen that occurs with aging and predicts physical frailty accompanying several chronic diseases including diabetes mellitus with peripheral neuropathy and to a lesser extent obesity. The results of this study demonstrate that BMI and excess body fatness (obesity) may contribute to physical frailty in EO participants more than LE muscle strength. Our results also suggest that strength assessment of several muscle groups of the LEs predict physical frailty to a larger extent than a single muscle group for individuals with generalized sarcopenia. Clinical Relevance: Our study suggests there are likely many contributors to physical frailty among individuals seen routinely by physical therapists. A more comprehensive and thorough understanding of the role of sarcopenia in physical frailty may help determine optimal rehabilitation strategies in the amelioration of sarcopenic skeletal muscles. Supported by the NIH T32 HD 007434, RO1 DK 59224, RO1 AG 025501.

Elevated plantar pressures in neuropathic diabetic patients with claw/hammer toe deformity

Elevated plantar foot pressures during gait in diabetic patients with neuropathy have been suggested to result, among other factors, from the distal displacement of sub-metatarsal head (MTH) fat-pad cushions caused by to claw/hammer toe deformity. The purpose of this study was to quantitatively assess these associations. Thirteen neuropathic diabetic subjects with claw/hammer toe deformity, and 13 age- and gender-matched neuropathic diabetic controls without deformity, were examined. Dynamic barefoot plantar pressures were measured with an EMED pressure platform. Peak pressure and force–time integral for each of 11 foot regions were calculated. Degree of toe deformity and the ratio of sub-MTH to sub-phalangeal fat-pad thickness (indicating fat-pad displacement) were measured from sagittal plane magnetic resonance images of the foot. Peak pressures at the MTHs were significantly higher in the patients with toe deformity (mean 626 (SD 260) kPa) when compared with controls (mean 363 (SD 115) kPa, P<0.005). MTH peak pressure was significantly correlated with degree of toe deformity ( r=−0.74) and with fat-pad displacement ( r=−0.71) ( P<0.001). The ratio of force–time integral in the toes and the MTHs (toe-loading index) was significantly lower in the group with deformity. These results show that claw/hammer toe deformity is associated with a distal-to-proximal transfer of load in the forefoot and elevated plantar pressures at the MTHs in neuropathic diabetic patients. Distal displacement of the plantar fat pad is suggested to be the underlying mechanism in this association. These conditions increase the risk for plantar ulceration in these patients.

Pressure relief and load redistribution by custom-made insoles in diabetic patients with neuropathy and foot deformity

Objective. To study the effects of custom-made insoles on plantar pressures and load redistribution in neuropathic diabetic patients with foot deformity. Design. Cross-sectional. Background. Although custom-made insoles are commonly prescribed to diabetic patients, little quantitative data on their mechanical action exists. Methods. Regional in-shoe peak pressures and force-time integrals were measured during walking in the feet of 20 neuropathic diabetic subjects with foot deformity who wore flat or custom-made insoles. Twenty-one feet with elevated risk for ulceration at the first metatarsal head were analysed. Load redistribution resulting from custom-made insoles was assessed using a new load-transfer algorithm. Results. Custom-made insoles significantly reduced peak pressures and force-time integrals in the heel and first metatarsal head regions; pressures and integrals were significantly increased in the medial midfoot region compared with flat insoles. Custom-made insoles successfully reduced pressures in and integrals at the first metatarsal head in 7/21 feet, were moderately successful in another seven, but failed in the remaining seven. Load transfer was greatest from the lateral heel to the medial midfoot regions. Conclusions. Custom-made insoles were more effective than flat insoles in off-loading the first metatarsal head region, but with considerable variability between individuals. Most off-loading occurred in the heel (not a region typically at risk). The load transfer algorithm effectively analyses custom-made-insole action. Relevance Because similar insole modifications apparently exert different effects in different patients, a comprehensive evaluation of custom designs using in-shoe pressure measurement should ideally be conducted before dispensing insoles to diabetic patients with neuropathy and foot deformity.

Three-dimensional stress analysis for the mechanics of plantar ulcers in diabetic neuropathy.

In diabetic neuropathic subjects, the hardness of foot sole soft tissue increases, and its thickness reduces, in different foot sole areas. Finite element analysis (FEA) of a three-dimensional two-arch model of the foot was performed to evaluate the effect of foot sole stresses on plantar ulcer development. Three sets of foot sole soft-tissue properties, i.e. isotropic (with control hardness value), diabetic isotropic (with higher hardness value) and anisotropic diabetic conditions, were simulated in the push-off phase, with decreasing foot sole soft-tissue thicknesses in the forefoot region, and the corresponding stresses were calculated. The results of the stress analyses for diabetic subject (anisotropic) foot models showed that, with non-uniformly increased hardness and decreased foot sole soft-tissue thickness, the normal and shear stresses at the foot sole increased (compared with control values) by 52.6% and 53.4%, respectively. Stress analyses also showed high ratios of gradients of normal and shear stresses of the order of 6.6 and 3.3 times the control values on the surface of the foot sole, and high relative values of stress gradients for normal and shear stresses of 6.25 and 4.35 times control values, respectively, between the foot sole surface and the adjacent inner layer of the foot sole, around a particular region of the foot sole with anisotropic properties. These ratios of high gradients and relative gradients of stresses due to changes in soft-tissue properties may be responsible for the development of plantar ulcers in diabetic neuropathic feet.

Standing foot pressure image analysis for variations in foot sole soft tissue properties and levels of diabetic neuropathy

This paper presents the results of the study undertaken on diabetic neuropathic subjects to find the relationship between the standing foot pressure parameter, power ratio (PR, ratio of high frequency power to the total power in the power spectrum of standing foot pressure image distribution obtained by optical pedobarograph), the foot sole hardness, and foot sole thicknesses at different levels of sensation loss. Spatial frequency distributions in the standing foot pressure images are analyzed to calculate the PR in each foot sole area for different levels of foot sole sensation loss and mechanical properties of foot sole hardness and thicknesses. The results show that the increase in PR in the upper foot sole hardness or Shore levels (30–40) is 1.4–3.7 times the corresponding increase in lower Shore levels (20–30), implying a higher possibility of development of plantar ulcers when the plantar surface becomes hard, combined with increase in sensation loss. It is observed that plantar ulcers are found to develop (i) for foot sole hardness or Shore values of 30 at sensation level of 4.5 gm and (ii) for Shore values of 40 and above at sensation levels of 10 and >10 gm, PR being high (29, 48 and 58, respectively) and the foot sole thicknesses are also greater than the corresponding normal values. Thus, different degrees of increase of all the three factors, namely, hardness, thickness and foot pressure distribution parameters in different levels of loss of foot sole sensation (or degrees of neuropathy) contribute to formation of foot sole ulcers in diabetic subjects.

Influence of the diabetic neuropathy on the behavior of electromyographic and sensorial responses in treadmill gait

Objective. We describe and interpret self-cadence treadmill walking by neuropathic diabetic subjects under biomechanical and somatosensorial considerations. Design. EMG variables during stance phase of neuropathic diabetic subjects were acquired and analyzed. We also evaluated sensorial and motor aspects of the feet and legs. Methods. The experimental procedures are divided as follows: (a) determination of the sensitive cronaxie and pain tolerance in selected plantar areas, (b) determination and description of temporal aspects of EMG patterns of the vastus lateralis, tibialis anterior and lateral gastrocnemius of both sides during treadmill walking. We analyze and compare the results of the sensitive cronaxie, pain tolerance and the EMG parameters obtained by two experimental groups: diabetic neuropathic ( n=20) and non-diabetic control subjects ( n=20). Results. The somatosensorial responses and pain tolerance threshold in the diabetic neuropathic group were significantly higher and considered far from the normal patterns. The EMG responses of the thigh and leg muscles in the diabetic neuropathic group were delayed if compared to the normal recruitment pattern, especially the tibialis anterior and vastus lateralis. Conclusions. These findings lead us to conclude that probably central and/or peripheral control mechanisms of the gait of neuropathic diabetic patients are altered due to somatosensorial and motor deficits. The mechanism of load reduction during walking was considered inefficient because of the activation delay of the vastus lateralis and tibialis anterior. We have concluded that the peripheral diabetic neuropathy damages not only somatosensorial and motor sources but also intrinsic mechanisms of motor control leading to alterations in the ankle efficiency in gait. This resulting distal inefficiency compromises some of the principal requirements for gait, such as progression and balance. Relevance This investigation is based on an innovating thematic approach involving the diabetic peripheral neuropathy. This innovation concerns the use of EMG and an instrumented treadmill in a clinical application to study and interpret the motor control during gait in neuropathic diabetic patients.

Parameters for analysis of walking foot pressures at different levels of diabetic neuropathy and detection of plantar ulcers at early stages

In this paper, studies are performed on a large number of diabetic patients belonging to different levels of planar sensation loss, using foot pressure parameters, i.e., normalized peak pressure (NPP), pressure contact ratio (PCR) and their gradients, which include effects of the weight of the subject, velocity of walking and duration of high pressures in all the foot sole areas. The foot areas of the diabetic subjects are scanned in ten specified areas using Semmes-Weinstein nylon monofilaments to quantify the different levels of sensation loss in diabetic neuropathy. A statistical study of the mean maximum values of these parameters, in different plantar areas of the feet of diabetic neuropathic subjects (in different levels of sensation loss), indicateds distinguishing trends. Good correlations are found between the quantified levels of sensation loss and foot pressure parameters in the areas where there is high incidence of plantar ulcers. The study shows that plantar ulcers could at an early stage (level) of sensation loss and also confirms that specially designed footwear helps in reducing foot pressure parameters of diabetic neuropathic feet and thereby could prevent plantar ulcer. The NPP and PCR transforms calculated on-line (using specially developed software) help the clinician to quickly determine the heavily-loaded foot areas that could be the sites of ulceration in the early level of plantar sensation loss and to take necessary action to prevent further damage to the foot sole.

Vibration perception threshold testing in patients with diabetic neuropathy: ceiling effects and reliability.

To test the reliability of a new vibrometer (Maxivibrometer) which was constructed so that vibration perception threshold (VPT) could be determined without the disadvantage of the off-scale measurements frequently experienced with the Biothesiometer. The two devices were compared and tested on a group of diabetic neuropathic subjects and a group of healthy, matched control subjects. VPT was tested on the plantar surface of the feet. The Maxivibrometer gave an actual measurement in all cases even if subjects were severely neuropathic. The replication-to-replication and day-to-day intraclass correlation coefficients for the Maxivibrometer VPT were, except in one case, above 0.94, indicating excellent reliability. The Biothesiometer VPT could also be measured with excellent reliability but only within a limited range of mild to moderate neuropathy, so it appears to be an appropriate screening tool. The replication-to-replication intraclass correlation coefficient was 0.93. Because VPT could be measured over a wide range with the Maxivibrometer, it was demonstrated that loss of sensation in diabetic neuropathy can progress far beyond the maximum VPT value of the Biothesiometer. The wide measurement range and the excellent reliability make the Maxivibrometer a valuable research tool to quantify loss of sensation, particularly in the presence of severe neuropathy and to record changes over time. Diabet. Med. 18, 469-475 (2001)

Structural and functional aspects of the diabetic foot

INTRODUCTION:: It has been well documented that, on average, patients with diabetes mellitus (DM) have higher plantar pressures than persons without DM, and there are several hypotheses why this may be -- many focused on the role of peripheral neuropathy. The purposes of this study were: (A) To identify and quantify structural differences between age-matched diabetic and non diabetic subjects, and (B) to develop predictive equations for peak pressure in these same patients. METHODS:: Standardized lateral and dorsi-plantar weight bearing plain radiographs of the right foot and ankle of 50 symptom free (NDM), 32 diabetic with no signs of neuropathy (NNP), and 73 diabetic neuropathic (NP) subjects were taken by a single radiographer. Twenty six angular and linear measurements were then made from the films. Plantar pressure distribution from three first step walking trials were collected and peak pressures at 10 discrete sites were determined for each step, and averaged. A one-way ANOVA with Tukey post hoc tests was conducted to test for differences between the means of each of the 26 radiographic measurements at the 0.01 significant level. Regression analysis was also used to predict the ln(pressure) under the heel, midfoot, mth1, mth2, and mth5 regions from the radiographic measurements, range of motion at the talocrural and first metatarsophalangeal joints and weight, for each of the 3 groups independently. RESULTS:: Significant differences were found among the three groups in 5 of the 26 radiographic measurements (Table 1). These included the thickness of the first, second and third metatarsals from the AP view (MT1, MT2 and MT3 -- generally > in NP), and the sesamoid height (NP > others) and fifth metatarsal head height (NDM < others). In addition, non significant trends were found in 4 other radiographic measurements. Regression analysis identified groups of up to five[Table: see text] predictors which accounted for between 27% and 62% of the variance in peak plantar pressure in different subject groups and foot regions. DISCUSSION AND CONCLUSIONS:: We conclude that objective differences in foot structure are present in diabetic neuropathic subjects, and that DM per se is apparently not a factor in these differences. We also concluded that static foot structure accounts for anywhere between approximately 30% to 60% of the variance in regional peak pressure, depending on the region investigated. In most cases predictions were higher in the midfoot and forefoot.