The assessment of diabetic polyneuropathy in daily clinical practice: reproducibility and validity of Semmes Weinstein monofilaments examination and clinical neurological examination

PLANTAR SENSATION AND BALANCE IN PATIENTS WITH TYPE 2 DIABETES MELLITUS WITH AND WITHOUT PERIPHERAL NEUROPATHY

The aim of the study was to investigate the effect of diabetes on plantar sense and balance in patients with type 2 diabetes mellitus (T2DM). The study included 300 subjects divided into three groups: 100 T2DM patients with diabetic peripheral neuropathy (group 1); 100 T2DM patients without peripheral neuropathy (group 2); and 100 subjects without DM (group 3). Berg Balance Scale (BBS), Timed Up and Go test (TUG), single leg test with eyes open and closed, and plantar sensory tests were applied in the subjects. Study results showed significant differences in plantar sensory tests, BBS, TUG and single leg test among the three groups (p<0.05). In addition, duration of DM and medication were negatively correlated with single leg test both with eyes open and closed, but showed positive correlation with plantar sense and TUG test. Furthermore, the length of insulin therapy showed positive correlation with plantar sense and TUG test and negative correlation with BBS (p<0.05). In conclusion, DM has an effect on plantar sense and balance, and there is a relation between the duration of DM and balance problems. Balance problems are observed more often in patients with neuropathy.

Impairment of microvascular blood flow in patients with type 2 diabetes and cardiovascular autonomic neuropathy

BACKGROUND: Diabetic autonomic neuropathy is the reason for early morbidity and mortality on diabetic patients. The pathology not only cardiac innervation but microvascular is presented.

AIMS: We estimated the parameters of skin microvascular blood flow in accordance with cardiovascular autonomic neuropathy (CAN) staging in diabetic patients. We also assessed other risk factors of CAN in patients with diabetes.

MATERIALS AND METHODS: We included 76 patients with type 2 diabetes in the study (24 patients with resent-onset diabetes and/or diabetes without microvascular complications, 26 with diabetic sensorimotor neuropathy (SMN) and 26 with SMN and previous history of diabetic foot amputation). The SMN was diagnosed on the basis of patients complaints, anamnesis and data of clinical neurological examinations. CAN was detected using several cardiovascular autonomic reflex tests (CART) as a gold standard of diagnosis: the tilt-table test, a deepbreathing and Valsalva Maneuver, handgrip test, cold-stress vasoconstriction. According to the Toronto Diabetic Neuropathy Expert Group Recommendation all patients was separated on the groups: CAN 0 (all CARTs were normal), CAN 1 (possible/early CAN — one abnormal CART was presented), CAN 2 (definite/confirmed CAN –at least two abnormal CARTs were found), CAN 3 (severe/advanced CAN — in the cases of orthostatic hypotension in addition to CARTs abnormalities). Microvascular blood flow of skin at the nail roller of fingers skin was valuated at rest as well as in functional cold test by the method of High-frequency Ultrasonic Dopplerography using the “Minimax Doppler K” device (LLC JV “Minimax”, St. Petersburg, Russia).

RESULTS: CAN 1 was found in 8% diabetic patients without microvascular complications, 42 and 21% patients with SMN and diabetic foot amputations respectively. CAN 2 was diagnosed in 27% patients with SMN and 58% patients history of diabetic foot amputations. CAN 3 in 8% and 19% cases in patients with SMN and history of diabetic foot amputations respectively. The parameters of microvascular blood flow at rest were significantly decreased in patients with confirmed/severe CAN in comparison with early staging of CAN and patients without CAN (Vm=2.5±0.66 sm/sec vs. 4.4±0.54 sm/sec and 5.1±1.01 sm/sec respectively; p=0.0033). The abnormal result of cold test was detected in 94% patients with confirmed/ severe CAN and 26% patients with CAN 1.

CONCLUSIONS: This investigation has demonstrated in a cohort with type 2 diabetes patients with/without SMN and with/ without history of previously foot amputations that decrease the Vm (the variable of microvascular blood flow assessed by High-frequency Ultrasonic Dopplerography) lower than 2.4 sm/sec is associated with 6.4 times increased likelihood of confirmed/severe CAN as well as positive cold test result. That the patients with positive cold test results were 28.6 times more likely have confirmed/severe CAN.

Biopsychosocial Rehabilitation Treatment "Exposure In Vivo" for Patients with Painful Diabetic Neuropathy: Development of a Treatment Protocol

Objective

Painful diabetic neuropathy is associated with low quality of life, depression and anxiety. Patients are limited in their performance of activities of daily living due to fears related to their condition. Treatment modalities are needed to help patients cope with their pain and pain-related disability. Exposure in vivo is an effective treatment in other chronic pain syndromes, increasing patients’ functional ability and quality of life. This paper presents an Exposure in vivo treatment protocol for patients with painful diabetic neuropathy.

Protocol

An 8-week Exposure in vivo treatment protocol was specifically adapted to the needs and risks of patients with painful diabetic neuropathy. New screening tools were developed for patients with PDN; the Painful Diabetic Neuropathy Anxiety Rasch-Transformed Questionnaire (PART-Q30) identifies specific fears related to painful diabetic neuropathy (e.g. fear of hypoglycaemia); and a customized version of the Photograph-series Of Daily Activities (PHODA-PDN) detects fear-eliciting activities related to the condition in individual patients. During Exposure in vivo, catastrophic interpretations regarding painful stimuli are challenged and corrected, thereby diminishing pain-related fear and enabling the patient to re-engage in activities of daily living. An interdisciplinary team provides Exposure in vivo in 1-h sessions twice a week.

Discussion

To the best of our knowledge, this treatment protocol is the first intervention using Exposure in vivo specifically adapted to the needs and risks of patients with painful diabetic neuropathy.

Translation and Psychometric Properties of the Arabic Version of Michigan Neuropathy Screening Instrument in Type 2 Diabetes

OBJECTIVE

To translate the patient questionnaire section of the Michigan Neuropathy Screening Instrument (MNSI) into Arabic, examine the reliability of the translated version, and provide descriptive data on a sample of patients with type 2 diabetes.

METHODS

Researchers used the translation-back translation method to obtain MNSI Arabic. The test was then applied on 76 patients with type 2 diabetes. A subgroup of 25 patients answered MNSI Arabic twice to examine reliability.

RESULTS

The intraclass correlation coefficient was 0.87, revealing good reliability of MNSI Arabic. The most common symptoms patients complained of were numbness (62%), prickling feelings (57%), burning pain (47%), and pain with walking (46%).

CONCLUSION

Similar to the original MNSI version, our study demonstrates that the Arabic version of the MNSI questionnaire is a reliable tool for screening the symptomatic neuropathy status in patients with type 2 diabetes. Availability of this tool in Arabic will provide valuable and easy-to-obtain screening information regarding diabetic peripheral neuropathy that may help delay its complications by promoting early management.

The Effect of Shear Force on Skin Viability in Patients with Type 2 Diabetes

BACKGROUND

Shear is a major risk factor in the development of diabetic foot ulcers, but its effect on the skin of patients with type 2 diabetes mellitus (DM) remains to be elucidated. The aim was to determine skin responses to shear in DM patients with and without diabetic polyneuropathy (DNP).

METHODS

The forearm skin was loaded with 14.5 N shear (+2.4 kPa pressure) and with 3.5 kPa pressure for 30 minutes in 10 type 2 DM patients without DNP, 10 type 2 DM patients with DNP, and 10 healthy participants. A Sebutape collected IL-1α (measure of tissue damage). A laser Doppler flowmeter measured cutaneous blood cell flux (CBF) as a measure of the reactive hyperaemic skin response.

FINDINGS

Reactive hyperaemia and IL-1α release was significantly increased after shear loading in all three groups and was higher compared to the responses to pressure loading. The reactive hyperaemic response after shear loading was impaired in patients with type 2 DM compared to healthy participants but did not differ between patients with and without DNP. The reactive hyperaemic response was negatively correlated with the blood glucose level but did not correlate with the DNP severity score.

INTERPRETATION

Shear is important in the development of tissue damage, but the reparative responses to shear are impaired in patients with type 2 DM. DNP was not associated with altered skin responses, suggesting that the loss of protective sensation to sense shear to skin remains a key factor in the development of diabetic foot ulcers in patients with DNP.

Effects of a long-term lifestyle modification programme on peripheral neuropathy in overweight or obese adults with type 2 diabetes: the Look AHEAD study

AIMS/HYPOTHESIS

The aim of this study was to evaluate the effects on diabetic peripheral neuropathy (DPN) of a long-term intensive lifestyle intervention (ILI) programme designed to achieve and maintain weight loss.

METHODS

Beginning in 2001, a total of 5145 overweight or obese people with type 2 diabetes, aged 45-76 years, participating in the multicentre Look AHEAD (Action for Health in Diabetes) study were randomised to ILI (n = 2570) or to a diabetes support and education (DSE) control group (n = 2575) using a web-based management system at the study coordinating centre at Wake Forest School of Medicine (Winston-Salem, NC, USA). Randomisation was stratified by clinical centre and was not revealed to the clinical staff responsible for obtaining data on study outcomes. Because of the nature of the study, patients and the local centre interventionists were not blinded to the study group assignments. In addition, the coordinating centre staff members responsible for data management and statistical analyses were not blinded to the study group assignments. The interventions were terminated in September 2012, 9-11 years after randomisation, but both groups continued to be followed for both primary and secondary outcomes. Neuropathy evaluations included the Michigan Neuropathy Screening Instrument (MNSI) questionnaire completed at baseline in 5145 participants (ILI n = 2570, DSE n = 2575) and repeated annually thereafter and the MNSI physical examination and light touch sensation testing conducted in 3775 participants (ILI n = 1905, DSE n = 1870) 1-2.3 years after discontinuation of the intervention.

RESULTS

At baseline, the MNSI questionnaire scores were 1.9 ± 0.04 and 1.8 ± 0.04 in the ILI and DSE groups, respectively (difference not statistically significant). After 1 year, when weight loss was maximal in the ILI group (8.6 ± 6.9%) compared with DSE (0.7 ± 4.8%), the respective MNSI scores were 1.7 ± 0.04 and 2.0 ± 0.04 (p ≤ 0.001). Subsequently, the scores increased gradually in both groups, but remained significantly lower in the ILI group for the first 3 years and at the end of follow-up. In both groups, there was a significant association between changes in the MNSI scores and changes in body weight, HbA_1c and serum lipids. There were no significant between-group differences in the proportions of participants with MNSI physical examination scores ≥2.5, considered to be indicative of diabetic neuropathy. The light touch sensation measured separately in either the right or left big toes (halluces) did not differ between ILI and DSE, but when the data were combined for both toes, light touch was better preserved in the ILI group.

CONCLUSIONS/INTERPRETATION

ILI resulted in a significant decrease in questionnaire-based DPN, which was associated with the magnitude of weight loss. In both the ILI and DSE groups, changes in the MNSI score were also related to changes in HbA_1c and lipids. There were no significant effects of ILI on physical examination measures of DPN conducted 1-2.3 years after termination of the active intervention, except for light touch sensation, which was significantly better in the ILI group when measurements were combined for both toes. However, a potential limiting factor to the interpretation of the physical examination data is that no baseline studies are available for comparison.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00017953.

FUNDING

This work was funded by the National Institutes of Health through cooperative agreements with the National Institute of Diabetes and Digestive and Kidney Diseases.

Arterial stiffness, endothelial and cognitive function in subjects with type 2 diabetes in accordance with absence or presence of diabetic foot syndrome

Background

Endothelial dysfunction is an early marker of cardiovascular disease so endothelial and arterial stiffness indexes are good indicators of vascular health. We aimed to assess whether the presence of diabetic foot is associated with arterial stiffness and endothelial function impairment.

Methods

We studied 50 subjects with type 2 diabetes mellitus and diabetic foot syndrome (DFS) compared to 50 diabetic subjects without diabetic foot, and 53 patients without diabetes mellitus, by means of the mini mental state examination (MMSE) administered to evaluate cognitive performance. Carotid-femoral pulse wave velocity (PWV) and augmentation index (Aix) were also evaluated by Applanation tonometry (SphygmoCor version 7.1), and the RH-PAT data were digitally analyzed online by Endo-PAT2000 using reactive hyperemia index (RHI) values.

Results

In comparison to diabetic subjects without diabetic foot the subjects with diabetic foot had higher mean values of PWV, lower mean values of RHI, and lower mean MMSE. At multinomial logistic regression PWV and RHI were significantly associated with diabetic foot presence, whereas ROC curve analysis had good sensitivity and specificity in arterial PWV and RHI for diabetic foot presence.

Conclusions

Pulse wave velocity and augmentation index, mean RHI values, and mean MMSE were effective indicators of diabetic foot. Future research could address these issues by means of longitudinal studies to evaluate cardiovascular event incidence in relation to arterial stiffness, endothelial and cognitive markers.

Brachial Plexus Blockade Causes Subclinical Neuropathy: A Prospective Observational Study

Background: The objective of this study is to determine subclinical changes in hand sensation after brachial plexus blocks used for hand surgery procedures. We used Semmes-Weinstein monofilament testing to detect these changes. We hypothesized that patients undergoing brachial plexus nerve blocks would have postoperative subclinical neuropathy detected by monofilament testing when compared with controls. Methods: In total, 115 hand surgery adult patients were prospectively enrolled in this study. All patients undergoing nerve-related procedures were excluded as well as any patients with preoperative clinically apparent nerve deficits. Eighty-four patients underwent brachial plexus blockade preoperatively, and 31 patients underwent general anesthesia (GA). Semmes-Weinstein monofilament testing of the hand was performed preoperatively on both the operative and nonoperative extremities and postoperatively at a mean of 11 days on both hands. Preoperative and postoperative monofilament testing scores were compared between the block hand and the nonoperated hand of the same patient, as well as between the block hands and the GA-operated hands. Results: There were no recorded clinically relevant neurologic complications in the block group or GA group. A statistically significant decrease in sensation in postoperative testing in the operated block hand compared with the nonoperated hand was noted. When comparing the operated block hand with the operated GA hand, there was a decrease in postoperative sensation in the operated block hand that did not reach statistical significance. Conclusions: Brachial plexus blockade causes subtle subclinical decreases in sensibility at short-term follow-up, without any clinically relevant manifestations.

Diagnostic Accuracy of Monofilament Tests for Detecting Diabetic Peripheral Neuropathy: A Systematic Review and Meta-Analysis

OBJECTIVE

To systematically evaluate the diagnostic accuracy of monofilament tests for detecting diabetic peripheral neuropathy.

METHODS

We searched EMBASE (OvidSP), MEDLINE (OvidSP), the Cochrane Library, and Web of Science to identify diagnostic accuracy trials of monofilament tests for detecting diabetic peripheral neuropathy. We used a hierarchical summary receiver operating characteristics (HSROC) model to conduct the meta-analysis of diagnostic accuracy of monofilament tests for detecting diabetic peripheral neuropathy.

RESULTS

A total of 19 comparative trials met the inclusion criteria and were part of the qualitative synthesis. Eight trials using nerve conduction studies as the reference standard were selected for the meta-analysis. The pooled sensitivity and specificity of monofilament tests for detecting diabetic peripheral neuropathy were 0.53 (95% confidence interval (CI) 0.32 to 0.74) and 0.88 (95% CI 0.78 to 0.94), respectively. The pooled positive likelihood ratio and negative likelihood ratio were 4.56 (95% CI 2.93 to 7.10) and 0.53 (95% CI 0.35 to 0.81), respectively.

CONCLUSIONS

Our review indicated that monofilament tests had limited sensitivity for screening diabetic peripheral neuropathy. The clinical use of the monofilament test in the evaluation of diabetic peripheral neuropathy cannot be encouraged based on currently available evidence.

Assessment scales for the diagnosis of polyneuropathy

Epidemiological studies that investigate the occurrence and determinants of chronic length-dependent polyneuropathy are scarce. Population-based studies on polyneuropathy require a valid and reliable screening protocol with both good sensitivity and specificity. Several questionnaires and scoring scales have been developed for the detection of polyneuropathy, grading the severity of the disease, or evaluating the clinical course during follow-up. This review summarizes the aims and content of existing diagnostic polyneuropathy screening tools in order to help future studies decide which scale to use for screening in specific situations. We searched the PubMed database and identified 27 scales, 13 are based on symptoms alone, 8 on neurological signs alone, and 6 on a combination of symptoms and signs. Scales that combine questions concerning symptoms and a neurological examination with a focus on sensory alterations seem to have the best discriminatory power. However, all scoring scales were developed for and investigated in prespecified patient populations. Therefore, the generalizability of specific findings to the general population may be limited. We also discuss other limitations of existing scales. Future studies are required to determine which clinimetrically well-developed scales are preferred for use in population-based studies.

Interrater and intrarater reliability of the semmes-weinstein monofilament 4-2-1 stepping algorithm

INTRODUCTION

Semmes-Weinstein Monofilaments (SWM) are used to examine light touch sensation of the skin. Reliability of the 4-2-1 stepping algorithm approach for determining light touch detection thresholds has not been examined. The purpose of this study was to determine the interrater and intrarater reliability of the SWM 4-2-1 stepping algorithm on the plantar surface of the foot.

METHODS

Four raters with varying levels of SWM assessment experience tested light touch sensation over the plantar aspect of the first metatarsal head in 14 healthy adults. During the initial session, all raters performed the 4-2-1 stepping algorithm technique on each subject to determine interrater reliability. One week later, subjects were reassessed by 2 raters to determine intrarater reliability.

RESULTS

Interrater reliability ranged from moderate-to-good (ICC2,1  = 0.62-0.92). Intrarater reliability also ranged from moderate-to-good (ICC2,1  = 0.61-0.85).

CONCLUSIONS

The 4-2-1 stepping algorithm demonstrated acceptable interrater and intrarater reliability when measured in healthy adults. Muscle Nerve 53: 918-924, 2016.

Thresholds of cutaneous afferents related to perceptual threshold across the human foot sole

Perceptual thresholds are known to vary across the foot sole, despite a reported even distribution in cutaneous afferents. Skin mechanical properties have been proposed to account for these differences; however, a direct relationship between foot sole afferent firing, perceptual threshold, and skin mechanical properties has not been previously investigated. Using the technique of microneurography, we recorded the monofilament firing thresholds of cutaneous afferents and associated perceptual thresholds across the foot sole. In addition, receptive field hardness measurements were taken to investigate the influence of skin hardness on these threshold measures. Afferents were identified as fast adapting [FAI (n = 48) or FAII (n = 13)] or slowly adapting [SAI (n = 21) or SAII (n = 20)], and were grouped based on receptive field location (heel, arch, metatarsals, toes). Overall, perceptual thresholds were found to most closely align with firing thresholds of FA afferents. In contrast, SAI and SAII afferent firing thresholds were found to be significantly higher than perceptual thresholds and are not thought to mediate monofilament perceptual threshold across the foot sole. Perceptual thresholds and FAI afferent firing thresholds were significantly lower in the arch compared with other regions, and skin hardness was found to positively correlate with both FAI and FAII afferent firing and perceptual thresholds. These data support a perceptual influence of skin hardness, which is likely the result of elevated FA afferent firing threshold at harder foot sole sites. The close coupling between FA afferent firing and perceptual threshold across foot sole indicates that small changes in FA afferent firing can influence perceptual thresholds.

Balance and ankle muscle strength predict spatiotemporal gait parameters in individuals with diabetic peripheral neuropathy

AIMS

The aims of this study were to evaluate aspects of balance, ankle muscle strength and spatiotemporal gait parameters in individuals with diabetic peripheral neuropathy (DPN) and verify whether deficits in spatiotemporal gait parameters were associated with ankle muscle strength and balance performance.

MATERIALS AND METHODS

Thirty individuals with DPN and 30 control individuals have participated. Spatiotemporal gait parameters were evaluated by measuring the time to walk a set distance during self-selected and maximal walking speeds. Functional mobility and balance performance were assessed using the Functional Reach and the Time Up and Go tests. Ankle isometric muscle strength was assessed with a handheld digital dynamometer. Analyses of variance were employed to verify possible differences between groups and conditions. Multiple linear regression analysis was employed to uncover possible predictors of gait deficits.

RESULTS

Gait spatiotemporal, functional mobility, balance performance and ankle muscle strength were affected in individuals with DPN. The Time Up and Go test performance and ankle muscle isometric strength were associated to spatiotemporal gait changes, especially during maximal walking speed condition.

CONCLUSION

Functional mobility and balance performance are damaged in DPN and balance performance and ankle muscle strength can be used to predict spatiotemporal gait parameters in individuals with DPN.

Sensory-motor assessment in clinical research trials

The assessment of changes in sensory-motor function in clinical research presents a unique set of difficulties. Clinimetrics is the science of measurement as related to the identification of a clinical disorder, the tracing of the progression of the condition under study, and calculation of its impact. The selection of appropriate measures for clinical studies of sensory-motor function must consider validity, sensitivity, specificity, responsiveness, reliability, and feasibility. Reasonable measures of motor function in clinical research include manual examination of muscle strength, electrophysiology, functional scales, patient-reported outcomes (e.g., quality of life), and for severe conditions such as ALS, survival. The assessment of sensory function includes targeted electrophysiology and QOL, as well as more focused measures such as quantitative sensory testing and the scoring of positive symptoms. Each individual measure and each combination of endpoints has its strengths and limitations.

Foot care knowledge and practices and the prevalence of peripheral neuropathy among people with diabetes attending a secondary care rural hospital in southern India

Background:

Diabetes mellitus is a multifaceted disease and foot ulceration is one of its most common complications. Poor foot care knowledge and practices are important risk factors for foot problems among people with diabetes.

Aims:

To assess the knowledge and practices regarding foot care and to estimate the proportion of people with peripheral neuropathy among people with diabetes.

Settings and Design:

The cross-sectional study was conducted in 212 consecutive diabetes patients attending the out-patient department of a rural secondary care hospital.

Materials and Methods:

A questionnaire which included demographic details, knowledge questionnaire, and Nottingham assessment of functional foot care was administered. The Michigan Neuropathy Screening Instrument was used to identify peripheral neuropathy.

Statistical Analysis Used:

Descriptive analysis with frequency distribution for knowledge and practice scores, univariate analysis, and multiple logistic regressions to find significant variables associated with good knowledge and practice scores.

Results:

About 75% had good knowledge score and 67% had good foot care practice score. Male gender (OR 2.36, 95% CI 1.16–4.79), poor education status (OR 2.40, 95% CI 1.19–4.28), and lesser duration of diabetes (OR 2.24, 95% CI 1.15–4.41) were significantly associated with poor knowledge on foot care. Poor knowledge was associated with poor foot care practices (OR 3.43, 95% CI 1.75–6.72). The prevalence of neuropathy was 47% (95% CI 40.14–53.85) and it was associated with longer duration of the disease (OR 2.18, 95% CI 1.18–4.04).

Conclusion:

There exist deficiencies in knowledge and practices regarding foot care. Male gender, low education, and lesser duration of diabetes are associated with poor knowledge scores. The prevalence of diabetic peripheral neuropathy is high.

Multicenter trial of the proficiency of smart quantitative sensation tests

INTRODUCTION

We assessed proficiency (accuracy and intra- and intertest reproducibility) of smart quantitative sensation tests (smart QSTs) in subjects without and with diabetic sensorimotor polyneuropathy (DSPN).

METHODS

Technologists from 3 medical centers using different but identical QSTs independently assessed 6 modalities of sensation of the foot (or leg) twice in patients without (n = 6) and with (n = 6) DSPN using smart computer assisted QSTs.

RESULTS

Low rates of test abnormalities were observed in health and high rates in DSPN. Very high intraclass correlations were obtained between continuous measures of QSTs and neuropathy signs, symptoms, or nerve conductions (NCs). No significant intra- or intertest differences were observed.

CONCLUSIONS

These results provide proof of concept that smart QSTs provide accurate assessment of sensation loss without intra- or intertest differences useful for multicenter trials. Smart technology makes possible efficient testing of body surface area sensation loss in symmetric length-dependent sensorimotor polyneuropathies.

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

Background

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

Methods

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

Results

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

Conclusions

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

Trial registration

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

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

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

Increased forefoot loading is associated with an increased plantar flexion moment

The aim of this study was to identify the cascade of effects leading from alterations in force generation around the ankle joint to increased plantar pressures under the forefoot. Gait analysis including plantar pressure measurement was performed at an individually preferred and a standardized, imposed gait velocity in diabetic subjects with polyneuropathy (n=94), without polyneuropathy (n=39) and healthy elderly (n=19). The plantar flexion moment at 40% of the stance phase was negatively correlated with the displacement rate of center of pressure (r=-.749, p<.001 at the imposed, and r=-.693, p<.001 at the preferred gait velocity). Displacement rate of center of pressure was strongly correlated with forefoot loading (r=-.837, p<.001 at the imposed, and r=-.731, p<.001 at the preferred gait velocity). People with a relatively high plantar flexion moment at 40% of the stance phase, have a faster forward transfer of center of pressure and consequently higher loading of the forefoot. This indicates that interventions aimed at increasing the control of the roll-off of the foot may contribute to a better plantar pressure distribution.

Avaliação da função manual e da força de preensão palmar máxima em indivíduos com diabetes mellitus

O sucesso na realização de atividades manipulativas é crucial para um estilo independente. Como os diabéticos podem apresentar alterações sensoriais nas mãos, podem demonstrar alterações funcionais em tarefas manipulativas. Assim, o objetivo deste estudo foi comparar o desempenho de indivíduos diabéticos não neuropatas com o de não diabéticos em tarefas manipulativas e na capacidade de geração de força de preensão palmar máxima. Treze diabéticos sem diagnóstico de neuropatia (48,6±11,51 anos; 79,9±10,88 kg; 1,68 ±0,09 m) e 13 controles pareados por sexo e idade (48,5±10,09 anos; 76,44±11,79 kg; 1,69±0,1 m) participaram do estudo. A sensibilidade das mãos foi avaliada por meio do kit de monofilamentos Semmes-Weinstein e, em seguida, foram aplicados três testes comumente utilizados para avaliação da função manual na seguinte ordem: teste de função manual Jebsen Taylor (TFMJT), teste dos nove pinos nos buracos (9-PnB) e teste de força de preensão palmar máxima (FPmax). Os resultados do teste de sensibilidade cutânea indicaram que oito diabéticos apresentaram sensibilidade cutânea normal e cinco, alguma alteração sensorial detectável pelo monofilamento, a qual, no entanto, não os caracterizavam como neuropatas. Com relação aos testes funcionais, os resultados não indicaram qualquer diferença entre os grupos para os desempenhos nos três testes realizados (diabéticos e controles - TFMJT: 26,15±3,06 e 25,78±1,29 s; 9-PnB: 15,33±1,35 e 15,48±2,39 s; FPmax: 41,15±10,59 e 43,69±12,59 kgf). Assim, podemos concluir que indivíduos diabéticos sem neuropatia diabética periférica não apresentam qualquer alteração funcional nos membros superiores e na capacidade de gerar força de preensão palmar máxima.

Effective pharmacological treatment of painful diabetic neuropathy by nurse practitioners: results of an algorithm-based experience

OBJECTIVE

  To improve the care of patients with painful diabetic polyneuropathy (PDP) by a specialized outpatient clinic for individuals referred by general practitioners and to determine the effects on pain, quality of life, and patient satisfaction.

MATERIAL AND METHODS

  One hundred twenty-one patients were prospectively enrolled. At baseline and after 12 months at end of treatment, patients filled in a set of validated questionnaires on severity and interference of pain, quality of life, anxiety and depression, and patient satisfaction with the service offered.

SETTING

  The outpatient clinic is part of a regional chronic care management program, which includes both hospital-based endocrinologists and general practitioners.

RESULTS

  Twenty-eight patients (27%) did not need any further treatment after one visit to the outpatient clinic. As initial drug, pregabalin was the most commonly prescribed drug (65%); amitriptyline was prescribed in only 30% due to its contraindications. Improvements were found in all pain scores (P < 0.05). Pain interference was improved in sleep (P < 0.01), general activity, and mood (P < 0.05). More than half of the patients (65%) were satisfied with the treatment and wished no further medication changes; 52% had a treatment success defined as pain relief ≥ 30%. Medication was stopped due to inefficacy in 9% of patients and changed due to adverse effects in 20% of the patients.

CONCLUSIONS

  A specialized outpatient clinic for patients with PDP is an effective health care service. Using diagnostic instruments and a defined treatment algorithm, significant pain reduction was achieved in the majority of patients in a relative short period of time.

Sensitivity and specificity of von Frey's hairs for the diagnosis of peripheral neuropathy in patients with type 2 diabetes mellitus

OBJECTIVE

The aim was to evaluate von Frey's hairs as a diagnostic tool for peripheral neuropathy in type-2 diabetes patients with symptoms typical for diabetic neuropathy with respect to nerve conduction studies (NCSs) and a combination of clinical examination and NCS.

PATIENTS AND METHODS

65 patients with type-2 diabetes (33 men) with mean age 62.1 (SD 6.5) years, mean diabetes duration 17.5 (SD 9) years and mean symptom duration 5.2 (SD 4.3) years were examined with the set of von Frey's hairs. Diabetic neuropathy was diagnosed trough Neuropathy Disability Score (NDS). NCSs were performed on ulnar, peroneal, tibial and sural nerves.

RESULTS

Sensitivity of von Frey's hairs vs. NCS as the gold standard ranged from 37% to 79% and specificity from 65% to 87%. Sensitivity vs. combination of NDS and NCS ranged from 38% to 85% and specificity from 62% to 85%.

CONCLUSIONS

Von Frey's hairs have moderate sensitivity and specificity for diagnosis of neurophysiological and also clinical neuropathy. Being a fast and easy-to-perform procedure, they could be appropriate as a screening test in clinical practice.

Lower extremity muscle strength is reduced in people with type 2 diabetes, with and without polyneuropathy, and is associated with impaired mobility and reduced quality of life

AIM

The purpose of the present study was to distinguish the effects of both diabetes mellitus type 2 (DM2) and diabetic polyneuropathy (DPN) on mobility, muscle strength and health related quality of life (HR-QoL).

METHODS

DPN patients (n=98), DM2 patients without DPN (DC) (n=39) and healthy subjects (HC) (n=19) performed isometric and isokinetic lower limb muscle strength tests. Mobility was determined by a timed up and go test (TUGT), a 6 min walk test and the physical activity scale for the elderly questionnaire. HR-QoL was determined by the SF36 questionnaire.

RESULTS

DPN patients had moderate polyneuropathy. In both DPN and DC patients leg muscle strength was reduced by 30-50% compared to HC. Muscle strength was correlated with mobility tests, and reduced muscle strength as well as impaired mobility were associated with a loss of HR-Qol (all p<0.05). We did not observe major differences in muscle strength, mobility (except for the TUGT, p<0.01) and HR-QoL between diabetic patients with and without DPN.

CONCLUSION

DM2 patients, with and without DPN, have decreased maximal muscle strength in the lower limbs and impaired mobility. These abnormalities are associated with a loss of HR-QoL. The additional effect of moderate DPN was small in our patients.

Classification of the severity of diabetic neuropathy: a new approach taking uncertainties into account using fuzzy logic

OBJECTIVE

This study proposes a new approach that considers uncertainty in predicting and quantifying the presence and severity of diabetic peripheral neuropathy.

METHODS

A rule-based fuzzy expert system was designed by four experts in diabetic neuropathy. The model variables were used to classify neuropathy in diabetic patients, defining it as mild, moderate, or severe. System performance was evaluated by means of the Kappa agreement measure, comparing the results of the model with those generated by the experts in an assessment of 50 patients. Accuracy was evaluated by an ROC curve analysis obtained based on 50 other cases; the results of those clinical assessments were considered to be the gold standard.

RESULTS

According to the Kappa analysis, the model was in moderate agreement with expert opinions. The ROC analysis (evaluation of accuracy) determined an area under the curve equal to 0.91, demonstrating very good consistency in classifying patients with diabetic neuropathy.

CONCLUSION

The model efficiently classified diabetic patients with different degrees of neuropathy severity. In addition, the model provides a way to quantify diabetic neuropathy severity and allows a more accurate patient condition assessment.

Tactile assessment in children with cerebral palsy: a clinimetric review

This review evaluates the clinimetric properties of tactile assessments for children with cerebral palsy. Assessment of registration was reported using Semmes Weinstein Monofilaments (SWMs) or exteroception. Assessment of two-point discrimination was reported using the Disk-Criminator® or paperclip methods; Single point localization and double simultaneous were reported from the Neurosensory Motor Developmental Assessment (NSMDA); graphaesthesia was reported from the Sensory Integration and Praxis Test (SIPT); and stereognosis was assessed using Manual Form Perception from the SIPT and the Klingels method (Klingels, K. et al. (2010). Upper limb motor and sensory impairments in children with hemiplegic cerebral palsy. Can they be measured reliably? Disability and Rehabilitation, 32(5), 409-416) and the Cooper method (Cooper, J., Majnemer, A., Rosenblatt, B., & Birnbaum, R. (1995). The determination of sensory deficits in children with hemiplegic cerebral palsy. Journal of Child Neurology, 10, 300-309). The SIPT and NSMDA demonstrated stronger content validity. Inter-rater reliability was excellent for SIPT (ICC = 0.99) and exteroception (k = 0.88). Test-retest reliability was excellent for exteroception (k = 0.89) and stereognosis (ICC = 0.86; 100%), moderate for SIPT (r = 0.69-0.74) and poor for SWM (k = 0.22). Together these assessments measure tactile registration and spatial perception. Temporal and textural tests are to be developed for comprehensive tactile examination.

A Comparative study of examination scores and quantitative sensory testing in diagnosis of diabetic polyneuropathy

CONTEXT

Many advances have taken place in the detection of diabetic polyneuropathy with respect to examination scores, electrophysiological techniques and quantitative sensory testing.

AIM

This study aims to evaluate the discriminative power of the Diabetic Neuropathy Examination Score (DNE), 10-g Semmes-Weinstein Monofilament Examination (SWME) and Quantitative Sensory Testing by Vibration Perception Threshold (VPT) in the diagnosis of diabetic polyneuropathy and seek an optimal screening method in diabetic clinic.

MATERIALS AND METHODS

Hundred consecutive patients with Type 2 diabetes were subjected to Diabetic Neuropathy Symptom Score, DNE score, Semmes-Weinstein monofilament examination, Vibration Perception Threshold and Nerve Conduction Studies; mean +/- SD for the various characteristics were calculated. Sensitivity and specificity for the DNE, SWME and VPT were calculated, taking NCS as gold standard.

RESULTS

Seventy one of 100 subjects had evidence of neuropathy confirmed by Nerve Conduction Studies, while 29 did not have neuropathy. The DNE score gave a sensitivity of 83% and a specificity of 79%. The sensitivity of SWME was 98.5% and specificity was 55%. Vibration Perception Thresholds yielded a sensitivity of 86% and a specificity of 76%.

CONCLUSIONS

A simple neurological examination score is as good as Vibration Perception threshold in evaluation of polyneuropathy in a diabetic clinic. It may be a better screening tool for diagnosis of diabetic polyneuropathy in view of the cost effectiveness and ease of applicability.

A novel robotic monofilament test for diabetic neuropathy

OBJECTIVE

The use of the Semmes-Weinstein (SW) monofilament test is recommended as a screening method for diabetic neuropathy. It offers an important chance to prevent further complications of diabetic foot. We aimed to develop a prototype Robotic Monofilament Inspector that can be used as a standard machine for screening of diabetic neuropathy.

METHODS

Development was divided into three parts: computer software, control box, and Robotic Monofilament Inspector. The examiner conducted the SW test (by hand and by robotic inspector), vibration perception threshold, and Toronto Clinical Scoring System without knowledge of patient information. The unpaired t test or Wilcoxon rank-sum test was used to determine the differences between independent groups in terms of continuous outcomes, while the χ(2) test was used to determine categorical outcomes. Agreement between the various diabetic neuropathy tests was measured using the kappa statistic.

RESULTS

The SW test and vibration perception threshold were more valid tests for neuropathy than the Toronto test. The robotic test was in excellent agreement with the two former tests and appeared to be valid (kappa statistic, 0.35-0.81). Another indirect evidence for the validity of the robotic test was the finding that diabetic patients with foot ulcers had a higher prevalence of neuropathy (77%vs. 38%). This might indicate that the robotic test was more valid than the manual test.

CONCLUSION

The Robotic Monofilament Inspector could be used as a simple screening machine. This prototype may be developed further for routine clinical use.

Test-retest and interobserver reliability of quantitative sensory testing according to the protocol of the German Research Network on Neuropathic Pain (DFNS): a multi-centre study

Quantitative sensory testing (QST) is an instrument to assess positive and negative sensory signs, helping to identify mechanisms underlying pathologic pain conditions. In this study, we evaluated the test-retest reliability (TR-R) and the interobserver reliability (IO-R) of QST in patients with sensory disturbances of different etiologies. In 4 centres, 60 patients (37 male and 23 female, 56.4±1.9years) with lesions or diseases of the somatosensory system were included. QST comprised 13 parameters including detection and pain thresholds for thermal and mechanical stimuli. QST was performed in the clinically most affected test area and a less or unaffected control area in a morning and an afternoon session on 2 consecutive days by examiner pairs (4 QSTs/patient). For both, TR-R and IO-R, there were high correlations (r=0.80-0.93) at the affected test area, except for wind-up ratio (TR-R: r=0.67; IO-R: r=0.56) and paradoxical heat sensations (TR-R: r=0.35; IO-R: r=0.44). Mean IO-R (r=0.83, 31% unexplained variance) was slightly lower than TR-R (r=0.86, 26% unexplained variance, P<.05); the difference in variance amounted to 5%. There were no differences between study centres. In a subgroup with an unaffected control area (n=43), reliabilities were significantly better in the test area (TR-R: r=0.86; IO-R: r=0.83) than in the control area (TR-R: r=0.79; IO-R: r=0.71, each P<.01), suggesting that disease-related systematic variance enhances reliability of QST. We conclude that standardized QST performed by trained examiners is a valuable diagnostic instrument with good test-retest and interobserver reliability within 2days. With standardized training, observer bias is much lower than random variance. Quantitative sensory testing performed by trained examiners is a valuable diagnostic instrument with good interobserver and test-retest reliability for use in patients with sensory disturbances of different etiologies to help identify mechanisms of neuropathic and non-neuropathic pain.

An adaptive procedure for routine measurement of light-touch sensitivity threshold

Quantitative sensory testing with Semmes-Weinstein monofilaments suffers from several pitfalls. Our aims were to assess the reliability of these filaments for touch-pressure threshold detection, develop and validate a rapid and accurate procedure for measurements at the bedside, and establish normative data. After calibration of the monofilaments, an adaptive staircase algorithm was validated and used to establish normative data in healthy subjects. Calibration showed significant differences between manufacturer- and investigator-produced data. The relative humidity significantly affected the force exerted by the filaments. The adaptive procedure showed good accuracy and substantial time-saving. Touch-pressure thresholds showed significant gender differences (mean +/- 2 SD for females/males: 2.82-12.3/3.09-17.78 g/mm(2)). The influence of body site and age is small. Accurate use of Semmes-Weinstein monofilaments requires prior calibration, correction for humidity, and use of a validated procedure. In this study we provide normative data that can be used with our algorithm.

Reliability of superficial peroneal, sural, and medial plantar nerve conduction studies: analysis of statistical methods

The reliability of medial plantar, sural, and superficial peroneal nerve conduction studies (NCS) has not been widely studied. These nerves are usually involved in distal sensory neuropathies and their serial study is relevant in the clinical setting.

PURPOSE

To determine the inter- and intrarater reliability of superficial peroneal, sural, and medial plantar NCS in healthy participants.

METHODS

Two raters performed the bilateral NCS twice in 20 healthy participants (23.5 +/- 3.5 years). Reliability was analyzed by the Bland-Altman method and intraclass correlation coefficient (ICC). Variability was established by the coefficient of variation.

RESULTS

The Bland-Altman method showed a good level of intra- and interrater agreement for all nerves. The amplitude (rater 1) and latency of the medial plantar nerve and the amplitude of the sural nerve (rater 2) had an intrarater ICC of >or=0.75. Interrater analysis showed concordance levels between moderate and very low. The highest coefficients of variations were found for amplitude and the lowest for nerve conduction velocity.

CONCLUSIONS

Although the Bland-Altman method confirmed a good intra- and interrater reliability of the studied nerves, ICC analyses showed mixed results. These statistical approaches are complementary, and each one has advantages and disadvantages that must be considered in their application and interpretation.

Reliability of the Semmes Weinstein Monofilaments to measure coetaneous sensibility in the feet of healthy subjects

PURPOSE

To determine the intrarater-reliability, interrater-reliability and normal reference scores of the Semmes Weinstein Monofilament test (SWM) of the feet of healthy subjects. In addition, the stability of the SWM for prospective use was assessed by determining systematic changes in sensory thresholds.

METHODS

Interrater-reliability was assessed on five locations of the plantar side of both feet using monofilaments 1.65, 2.36, 2.44, 2.83, 3.22, 3.61, 3.84, 4.08, 4.31, 5.56, 6.65 in 60 healthy subjects by two or three investigators (test day 1). Intrarater-reliability and systematic changes in sensory thresholds were assessed 3 weeks later (test day 22) by one investigator.

RESULTS

Median interrater-reliability for the five test locations for both feet was poor to moderate. Median intrarater-reliability was good for the left foot and poor to moderate for the right foot. Significantly lower median sensory thresholds were found for the first SWM measurement at test day 22 compared to the first and second measurement of test day 1. Given the observed reliability of the SWM, a normal sensory score for the feet was situated between monofilament 3.22 and 4.08.

CONCLUSIONS

The SWM are reliable when measured by one researcher. Systematic changes in sensory thresholds were observed; therefore, the stability of the SWM for use in prospective studies could not be verified.

Repeatability of cold pain and heat pain thresholds: The application of sensory testing in migraine research

Normal heat pain threshold (HPT) and cold pain threshold (CPT) repeatability should be estimated in order to identify thermal allodynia in longitudinal studies, but such data are scarce in the literature. The aim of our study was to estimate normal HPT and CPT repeatability in the face, forehead, neck and hand. In addition, we reviewed briefly normative studies of thermal pain thresholds relevant for headache research. Thermal pain thresholds were measured on three different days in 31 healthy headache-free subjects. Coefficients of repeatability and normal limits were calculated. HPT and CPT were lowest in the face. Pooled across regions, the lower repeatability limit for the test/retest ratio was 63% for HPT and 55% for CPT. The upper normal CPT limit varied between 24.5°C and 29.7°C. Lower HPT limits ranged between 35.5°C and 40.8°C. Quantitative sensory methods provide useful information about headache and pain pathophysiology, and it is important to estimate the normal test/retest repeatability range in follow-up studies.

Accuracy of monofilament testing to diagnose peripheral neuropathy: a systematic review

PURPOSE

We wanted to summarize evidence about the diagnostic accuracy of the 5.07/10-g monofilament test in peripheral neuropathy.

METHODS

We conducted a systematic review of studies in which the accuracy of the 5.07/10-g monofilament was evaluated to detect peripheral neuropathy of any cause using nerve conduction as reference standard. Methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool.

RESULTS

We reviewed 173 titles and abstracts of articles to identify 54 potentially eligible studies, of which 3 were finally selected for data synthesis. All studies were limited to patients with diabetes mellitus and showed limitations according to the QUADAS tool. Sensitivity ranged from 41% to 93% and specificity ranged from 68% to 100%. Because of the heterogenous nature of the studies, a meta-analysis could not be accomplished.

CONCLUSIONS

Despite the frequent use of monofilament testing, little can be said about the test accuracy for detecting neuropathy in feet without visible ulcers. Optimal test application and defining a threshold should have priority in evaluating monofilament testing, as this test is advocated in many clinical guidelines. Accordingly, we do not recommend the sole use of monofilament testing to diagnose peripheral neuropathy.

The Semmes Weinstein monofilament examination as a screening tool for diabetic peripheral neuropathy

OBJECTIVE

The purpose of this systematic review is to evaluate current evidence in the literature on the efficacy of Semmes Weinstein monofilament examination (SWME) in diagnosing diabetic peripheral neuropathy (DPN).

METHODS

The PubMed database was searched through August 2008 for articles pertaining to DPN and SWME with no language or publication date restrictions. Studies with original data comparing the diagnostic value of SWME with that of one or more other modalities for DPN in patients with diabetes mellitus were analyzed. Data were extracted by two independent investigators. Diagnostic values were calculated after classifying data by reference test, SWME methodology, and diagnostic threshold.

RESULTS

Of the 764 studies identified, 30 articles were selected, involving 8365 patients. There was great variation in both the reference test and the methodology of SWME. However, current literature suggests that nerve conduction study (NCS) is the gold standard for diagnosing DPN. Four studies were identified which directly compared SWME with NCS and encompassed 1065 patients with, and 52 patients without diabetes mellitus. SWME had a sensitivity ranging from 57% (95% confidence interval [CI], 44% to 68%) to 93% (95% CI, 77% to 99%), specificity ranging from 75% (95% CI, 64% to 84%) to 100% (95% CI, 63% to 100%), positive predictive value (PPV) ranging from 84% (95% CI, 74% to 90%) to 100% (95% CI, 87% to 100%), and negative predictive value (NPV) ranging from 36% (95% CI, 29% to 43%) to 94% (95% CI, 91% to 96%).

CONCLUSIONS

There is great variation in the current literature regarding the diagnostic value of SWME as a result of different methodologies. To maximize the diagnostic value of SWME, a three site test involving the plantar aspects of the great toe, the third metatarsal, and the fifth metatarsals should be used. Screening is vital in identifying DPN early, enabling earlier intervention and management to reduce the risk of ulceration and lower extremity amputation.

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.

Diabetic polyneuropathy: an update

PURPOSE OF REVIEW

To examine current issues in the diagnosis and treatment of diabetic polyneuropathy.

RECENT FINDINGS

Diabetic neuropathies are common and rising in prevalence with the global burden of type 2 diabetes. Polyneuropathy is also emerging as a complication of impaired glucose tolerance, without frank diabetes. Ideas about the pathogenesis of diabetic polyneuropathy have evolved, and some new pathogenic mechanisms are being considered. These include roles for direct insulin signaling on neurons and axons that transduce growth signals, actions of the cleaved C-peptide product of the insulin prohormone, abnormal signaling by advanced glycation endproducts on neuronal and glial receptors and activation of poly (ADP-ribose) polymerase in microvessels and neurons. Manipulation of these pathways may offer new therapeutic approaches. Ideas about neuronal targets in the treatment of neuropathic pain have also advanced emphasizing abnormal sodium and calcium channel signaling.

SUMMARY

Consideration of diabetic polyneuropathy as a unique neurodegenerative condition has generated interest in new pathways involved in its development. A new round of clinical trials that address its pathogenesis may be welcome, as recent attempts have been largely disappointing. In the interim, several forms of therapy for neuropathic pain are available.

Sensory evaluation of the hands in patients with Charcot-Marie-Tooth disease using Semmes-Weinstein monofilaments

In this study, the intra- and interobserver reliability of the Semmes-Weinstein monofilaments (SWMFs) was determined in the hands of 15 patients with Charcot-Marie-Tooth disease. In addition, the amount and distribution of sensory loss in the hand, and the relation between sensory loss, intrinsic muscle strength, and hand dexterity was explored in 45 patients. SWMF testing had good intra- and interobserver reliability with intraclass correlation coefficients of 0.91 and 0.86, respectively. The SWMF testing revealed normal sensory function in 43% of all six locations. The average loss of the intrinsic hand muscle strength was 57%. Poor strength was found in patients with both poor and with good sensory function. The correlation between the measurements of intrinsic muscle strength and the Sollerman test for dexterity was 0.70.