Traditional Methods versus Quantitative Sensory Testing of the Feet at Risk

New Horizons in Diabetic Neuropathies: An Updated Review on their Pathology, Diagnosis, Mechanism, Screening Techniques, Pharmacological, and Future Approaches

BACKGROUND

One of the largest problems for global public health is diabetes mellitus (DM) and its micro and macrovascular consequences. Although prevention, diagnosis, and treatment have generally improved, its incidence is predicted to keep rising over the coming years. Due to the intricacy of the molecular mechanisms, which include inflammation, oxidative stress, and angiogenesis, among others, discovering treatments to stop or slow the course of diabetic complications is still a current unmet need.

METHODS

The pathogenesis and development of diabetic neuropathies may be explained by a wide variety of molecular pathways, hexosamine pathways, such as MAPK pathway, PARP pathway, oxidative stress pathway polyol (sorbitol) pathway, cyclooxygenase pathway, and lipoxygenase pathway. Although diabetic neuropathies can be treated symptomatically, there are limited options for treating the underlying cause.

RESULT

Various pathways and screening models involved in diabetic neuropathies are discussed, along with their possible outcomes. Moreover, both medicinal and non-medical approaches to therapy are also explored.

CONCLUSION

This study highlights the probable involvement of several processes and pathways in the establishment of diabetic neuropathies and presents in-depth knowledge of new therapeutic approaches intended to stop, delay, or reverse different types of diabetic complications.

Does Lower Extremity Nerve Decompression Surgery Improve Quality of Life?

BACKGROUND

Entrapment neuropathies are more prevalent in patients with diabetes than in healthy patients. The aim of this study was to assess the effects of lower extremity nerve decompression surgery on quality of life and clarify predictors of this surgical outcome and the incidence of surgical site problems.

METHODS

Patients who underwent lower extremity nerve decompression surgery between September of 2017 and March of 2019 were followed prospectively at the outpatient clinic of University Medical Center Utrecht. The common, superficial, and deep peroneal nerve and tibial nerve at the tarsal tunnel and soleal sling were decompressed if an entrapment was diagnosed. The primary study outcome was quality of life as measured by the Norfolk Quality of Life-Diabetic Neuropathy questionnaire. Secondary outcomes of interest were change in Michigan Neuropathy Screening Instrument score, predictors of the Norfolk score at follow-up, and the occurrence of complications.

RESULTS

Sixty patients underwent surgery (45 unilateral, 15 bilateral), with a median postoperative follow-up of 13.0 months (interquartile range, 7.3 to 18.0 months). Quality of life improved significantly in this period of observation [baseline median, 46.0 (34.0 to 62.0) versus follow-up median, 37.0 (20.0 to 60.0); p = 0.011], as did Michigan Neuropathy Screening Instrument scores [7.0 (5.0 to 9.0) versus 3.0 (0.0 to 6.5); p < 0.01]. Predictors of quality of life were a higher baseline quality of life score [β, 0.59 ( p = 0.001)], longer follow-up time [β, 2.34 ( p < 0.001)], and hypertension [β, 16.38 ( p = 0.03)]. A total of 26.7 percent of patients had surgical site problems, including wound infections (18.3 percent).

CONCLUSIONS

Lower extremity nerve decompression surgery significantly improves quality of life by reducing neuropathy symptoms in patients with lower extremity nerve compressions. Attention should be given to lowering the risk of wound complications.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

An overview of common peroneal nerve dysfunction and systematic assessment of its relation to falls

PURPOSE

Compression of the peroneal nerve is recognized as a common cause of falls. The superficial course of the peroneal nerve exposes it to trauma and pressure from common activities such as crossing of legs. The nerve can be exposed also to distress due to metabolic problems such as diabetes. The purpose of our manuscript is to review common peroneal nerve dysfunction symptoms and treatment as well as provide a systematic assessment of its relation to falls.

METHODS

We pooled the existing literature from PubMed and included studies (n = 342) assessing peroneal nerve damage that is related in any way to falls. We excluded any studies reporting non-original data, case reports and non-English studies.

RESULTS

The final systematic assessment included 4 articles. Each population studied had a non-negligible incidence of peroneal neuropathy. Peroneal pathology was found to be consistently associated with falls.

CONCLUSION

The peroneal nerve is an important nerve whose dysfunction can result in falls. This article reviews the anatomy and care of the peroneal nerve. The literature review highlights the strong association of this nerve's pathology with falls.

Cost-Effectiveness of Lower Extremity Nerve Decompression Surgery in the Prevention of Ulcers and Amputations: A Markov Analysis

BACKGROUND

The costs and health effects associated with lower extremity complications in diabetes mellitus are an increasing burden to society. In selected patients, lower extremity nerve decompression is able to reduce symptoms of neuropathy and the concomitant risks of diabetic foot ulcers and amputations. To estimate the health and economic effects of this type of surgery, the cost-effectiveness of this intervention compared to current nonsurgical care was studied.

METHODS

To estimate the incremental cost-effectiveness of lower extremity nerve decompression over a 10-year period, a Markov model was developed to simulate the onset and progression of diabetic foot disease in patients with diabetes and neuropathy who underwent lower extremity nerve decompression surgery, compared to a group undergoing current nonsurgical care. Mean survival time, health-related quality of life, presence or risk of lower extremity complications, and in-hospital costs were the outcome measures assessed. Data from the Rotterdam Diabetic Foot Study were used as current care, complemented with information from international studies on the epidemiology of diabetic foot disease, resource use, and costs, to feed the model.

RESULTS

Lower extremity nerve decompression surgery resulted in improved life expectancy (88,369.5 life-years versus 86,513.6 life-years), gain of quality-adjusted life-years (67,652.5 versus 64,082.3), and reduced incidence of foot complications compared to current care (490 versus 1087). The incremental cost-effectiveness analysis was -€59,279.6 per quality-adjusted life-year gained, which is below the Dutch critical threshold of less than €80,000 per quality-adjusted life-year.

CONCLUSIONS

Decompression surgery of lower extremity nerves improves survival, reduces diabetic foot complications, and is cost saving and cost-effective compared with current care, suggesting considerable socioeconomic benefit for society.

Health-related quality of life among rural adults with type 2 diabetes mellitus: a cross-sectional study

BACKGROUND

Previous reports about health-related quality of life (HRQoL) of type 2 diabetes mellitus (T2DM) concentrated on general patients rather than patients in rural areas with poor infrastructure and limited resources. Thus, the aims of this study were to evaluate the HRQoL of diabetics in the countryside and explore its influencing factors.

METHODS

A total of 23 053 participants aged from 18 to 79 years were drawn from the Henan Rural Cohort Study for this cross-sectional study. The HRQoL of participants were assessed by utility index and VAS-score of European Quality of Life Five Dimension Five Level Scale (EQ-5D-5L) instrument. Binary logistic regression, generalized linear and tobit regression models were used to estimate the potential influencing factors on HRQoL.

RESULTS

This study (23 053 participants) included 2231 T2DM patients with a crude prevalence of 9.68%. The utility index and VAS-score in health group were 0.96 ± 0.10 and 78.85 ± 14.53, while in T2DM group were 0.93 ± 0.15 and 74.09 ± 16.09, respectively. In total, most diabetics reported problem about pain/discomfort dimension. Being old, poverty, low physical activity, and with comorbidities was negatively related to HRQoL of diabetics, while high educational level was positively related to HRQoL.

CONCLUSION

HRQoL of rural T2DM patients depended on several sociodemographic factors. More attention should be paid to diabetics with poor socioeconomic status in rural areas.

CLINICAL TRIAL REGISTRATION

The Henan Rural Cohort Study has been registered at Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699) http://www.chictr.org.cn/showproj.aspx?proj=11375.

Ultrathin free flaps for foot reconstruction: impact on ambulation, functional recovery, and patient satisfaction

BACKGROUND

Plantar reconstruction is a complex procedure due to the paucity of tissue around the foot. Tissues used for reconstruction should provide similar properties, which can be accomplished by using ultra-thin flaps. Validated functional scales may provide essential information regarding patients' evolution.

METHODS

Information concerning a series of 12 cases of plantar reconstruction using ultra-thin free flaps was gathered retrospectively by the authors. Data from preoperative functional scores in Lower Extremity Functional Scale and American Orthopaedic Foot and Ankle Society scale were obtained from clinical records; these were compared to postoperative scores assigned prospectively during follow-up. Differences were determined using Student's t-test for paired samples. Objective measurements concerning evolution (ulceration, footwear usage, sensation), as well as patient satisfaction, were also explored.

RESULTS

The mean follow-up duration was 16.5 (range 12 to 24) months. The Lower Extremity Functional Scale scores mean modified from 39.1 to 60.2, p = 0.004; the American Orthopaedic Foot and Ankle Society scale mean modified from 42.2 to 53.4, p = 0.012. No patient showed plantar ulceration. Protective sensation was achieved in 75% of the patients, and 10 out of 12 could use regular footwear. All patients reported satisfaction with the surgical procedure.

CONCLUSIONS

Ultra-thin flaps for foot reconstruction are related to improvement in functional scales, high rates of patient satisfaction, and use of regular footwear as well as a limited range of complications.

Non-Targeted Metabolomic Analysis Reveals Serum Phospholipid Alterations in Patients with Early Stages of Diabetic Foot Ulcer

Diabetic foot ulcer (DFU) is a common complication of type 2 diabetes mellitus (T2DM) characterized by ulcer formation, which can lead to the amputation of lower extremities. However, the metabolic alterations related to this complication are not completely elucidated. Therefore, we carried out a metabolomic analysis of serum samples obtained from T2DM adult patients diagnosed with diabetic foot ulcer in a cross-sectional, observational, and comparative study. Eighty-four volunteers were classified into the following groups: without T2DM (control group, n = 30) and with T2DM and different stages of diabetic foot ulcer according to Wagner-Meggitt classification system: DFU G0 (n = 11), DFU G1 (n = 14), DFU G2 (n = 16), and DFU G3 (n = 13). The non-target metabolomic profile followed by chemometric analysis revealed that lysophosphatidylethanolamine (16:1) could be proposed as key metabolite related to the onset of diabetic foot ulcer; however, this phospholipid was not affected by diabetic foot ulcer progression. Therefore, further studies are necessary to validate these phospholipids as biomarker candidates for the early diagnosis of diabetic foot ulcer in T2DM patients.

Item reduction of the 39-item Rotterdam Diabetic Foot Study Test Battery using decision tree modelling

AIMS

Pedal sensory loss due to diabetes-related neuropathy can be graded by testing static two-point discrimination (S2PD), moving two-point discrimination (M2PD), static one-point discrimination (S1PD; eg, 10-g monofilament), and vibration sense and is included in the Rotterdam Diabetic Foot (RDF) Study Test Battery. The aim of this study is to investigate if decision tree modelling is able to reduce the number of tests needed in estimating pedal sensation.

METHODS

The 39-item RDF Study Test Battery (RDF-39) scores were collected from the prospective RDF study and included baseline (n = 416), first follow-up (n = 364), and second follow-up (n = 135) measurements, supplemented with cross-sectional control data from a previous study (n = 196). Decision tree analysis was used to predict total RDF-39 scores using individual test item data. The tree was developed using baseline RDF study data and validated in follow-up and control data. Spearman correlation coefficients assessed the reliability between the decision tree and original RDF-39.

RESULTS

The tree reduced the number of items from 39 to 3 in estimating the RDF-39 sum score. M2PD (hallux), S2PD (first dorsal web, fifth toe), vibration sense (interphalangeal joint), and S1PD (first dorsal web, fifth toe) measurements proved to be predictive. The correlation coefficients to original scores were high (0.76 to 0.91).

CONCLUSIONS

The decision tree was successful at reducing the number of RDF Test Battery items to only 3, with high correlation coefficients to the scores of the full test battery. The findings of this study aids medical decision making by time efficiently estimating pedal sensory status with fewer tests needed.

Balance, risk of falls, risk factors and fall-related costs in individuals with diabetes

AIMS

Sensory loss and impaired balance are considered risk factors of incident falls. The aim of this study was to assess the relationship between degree of foot sensation and balance, risk of falls, incidence of fall-related injuries and costs in a cohort of patients with diabetes.

METHODS

(Non)-neuropathic subjects participating in the Rotterdam Diabetic Foot Study were followed prospectively. Subjects underwent sensory testing of the feet (39 item Rotterdam Diabetic Foot Study Test Battery (RDF-39)); balance was assessed at the second follow-up (Brief-BESTest) as were data on incident falls. Medical records and financial data were abstracted to estimate fall-related morbidity and in-hospital costs.

RESULTS

A higher RDF-39 score, cerebral artery disease, type 2 diabetes, height and age were predictors of the Brief-BESTest total score. 41/296 patients (13.9%) reported two or more falls during follow-up. Predictors for recurrent falls were a higher RDF-39 score (aOR: 1.124, p < 0.0005), male gender (aOR: 0.319, p = 0.016), age (aOR: 0.938, p = 0.003) and type 2 diabetes (aOR: 3.157, p = 0.100). Thirty-one patients used medical resources (median US$ 440.45 (IQR: 179-1162).

CONCLUSIONS

Degree of sensory loss correlates significantly with an increased imbalance and risk of falls. The RDF-39 may be used as stratification tool in medical decision-making and patient information.

Development of grading scales of pedal sensory loss using Mokken scale analysis on the Rotterdam Diabetic Foot Study Test Battery data

INTRODUCTION

Loss of sensation due to diabetes-related neuropathy often leads to diabetic foot ulceration. Several test instruments are used to assess sensation, such as static and moving 2-point discrimination (S2PD, M2PD), monofilaments, and tuning forks.

METHODS

Mokken scale analysis was applied to the Rotterdam Diabetic Foot Study data to select hierarchies of tests to construct measurement scales.

RESULTS

We developed 39-item and 31-item scales to measure loss of sensation for research purposes and a 13-item scale for clinical practice. All instruments were strongly scalable and reliable. The 39 items can be classified into 5 hierarchically ordered core clusters: S2PD, M2PD, vibration sense, monofilaments, and prior ulcer or amputation.

DISCUSSION

Guided by the presented scales, clinicians may better classify the grade of sensory loss in diabetic patients' feet. Thus, a more personalized approach concerning individual recommendations, intervention strategies, and patient information may be applied.

Predicting ulcer-free survival using the discriminative value of screening test locations

BACKGROUND

Current guidelines recommend screening the feet of diabetic subjects with a 10-g monofilament or tuning fork. We investigated which tests and locations on the feet have the best predictive value regarding 1-year ulcer-free survival in diabetic subjects participating in the prospective Rotterdam Diabetic Foot Study.

METHODS

Decision tree analysis was used to predict ulcer-free survival based on responses from individual test locations (monofilaments on 10 sites, vibration sense was tested on both halluces and medial malleoli). Separate trees for patients with and without a history of diabetic foot ulcer (DFU) were developed.

RESULTS

Four hundred sixteen subjects (mean [SD] age, 61.8 years [12.4]; range, 21.6-90.2) were measured, of whom 24 developed new DFUs. Three tests exhibited discriminative and predictive properties: testing vibration sense on the medial malleolus and monofilament testing on heel and hallux. The decision tree to predict ulcer-free survival in patients with a history of DFU yielded a sensitivity of 87.0%, which was 99.6% for the tree of patients without a history of DFU.

CONCLUSION

The findings of this study aids medical decision making by discriminating between high- and low-risk patients of developing DFU using selective testing on sites with predictive properties.

Grading the loss of sensation in diabetic patients: A psychometric evaluation of the rotterdam diabetic foot study test battery

Introduction: Static‐ and moving 2‐point discrimination (S2PD, M2PD), 10‐g monofilaments‐ and tuning fork are validated outcome measures of clinical manifestations of diabetes‐related neuropathy. No modern statistical techniques have been used to investigate how well these instruments combine to measure sensory loss. Methods: To grade sensory loss at the feet, we fitted parametric forms of Item Response Theory models to the data of these instruments. Results: The fit statistics indicate that the loss of sensation is gradable, with readily available instruments. S2PD and M2PD are lost first, followed by vibration sense, the 10‐g monofilament and the ability to feel a cold stimulus. Conclusions: This test battery appears to provide sound measurement properties in a group of diabetic patients with diverse amounts of sensory loss. This approach may be used in clinical practice to grade sensory loss reliably and quickly, with instruments that are easy to use. Muscle Nerve58: 559–565, 2018

Optimization of Surgical Outcome in Lower Extremity Nerve Decompression Surgery

BACKGROUND

There is still debate regarding whether the surgical release of entrapped lower extremity nerves reduces complaints of associated neuropathy and results in gain of sensory function. The aim of this study was to investigate which factors are associated with a favorable surgical outcome, by follow-up of patients previously participating in a randomized controlled trial.

METHODS

The authors evaluated the 5-year follow-up of diabetic patients previously participating in the Lower Extremity Nerve Entrapment Study (LENS). Visual analogue pain scores, satisfaction, complaints, quality of life (i.e., 36-Question Short-Form Health Survey and EuroQol 5 Dimensions instrument), sensory function, and incident ulceration and amputation were assessed. Differences between patients who underwent unilateral versus bilateral decompressions were investigated.

RESULTS

Thirty-one of the original 42 LENS participants were measured, of which eight patients underwent additional decompression of the contralateral leg, after 12-month LENS follow-up. At 5 years, bilateral surgical patients (n = 8) had significantly lower pain scores and higher quality of life compared with unilateral surgical patients (n = 23), were younger, had a lower age when diagnosed with diabetes, and had a lower body mass index at baseline. Pain scores of the additional decompressed leg decreased in a manner similar to that of the initial decompressed leg during follow-up. Patients with severe preoperative sensory loss did worse; 41.2 percent of the LENS Follow-Up Study subjects underwent or considered undergoing contralateral surgery.

CONCLUSION

The authors' results suggest that the beneficial effects of lower extremity nerve decompression surgery are reserved for a select group of patients, of which preoperative nerve damage, age, duration of diabetes, and body mass index are important effect modifiers.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

The relationship between health related quality of life and sensory deficits among patients with diabetes mellitus

PURPOSE

(1) To profile sensory deficits examined in the ability to process sensory information from daily environment and discriminate between tactile stimuli among patients with controlled and un-controlled diabetes mellitus. (2) Examine the relationship between the sensory deficits and patients' health-related quality of life.

METHODS

This study included 115 participants aged 33-55 with uncontrolled (n = 22) or controlled (n = 24) glycemic levels together with healthy subjects (n = 69). All participants completed the brief World Health Organization Quality of Life Questionnaire, the Adolescent/Adult Sensory Profile and performed the tactile discrimination test.

RESULTS

Sensory deficits were more emphasized among patients with uncontrolled glycemic levels as expressed in difficulties to register sensory input, lower sensation seeking in daily environments and difficulties to discriminate between tactile stimuli. They also reported the lowest physical and social quality of life as compared to the other two groups. Better sensory seeking and registration predicted better quality of life. Disease control and duration contributed to these predictions.

CONCLUSIONS

Difficulties in processing sensory information from their daily environments are particularly prevalent among patients with uncontrolled glycemic levels, and significantly impacted their quality of life. Clinicians should screen for sensory processing difficulties among patients with diabetes mellitus and understand their impacts on patients' quality of life. Implications for Rehabilitation Patients with diabetes mellitus, and particularly those with uncontrolled glycemic levels, may have difficulties in processing sensory information from daily environment. A multidisciplinary intervention approach is recommended: clinicians should screen for sensory processing deficits among patients with diabetes mellitus and understand their impacts on patients' daily life. By providing the patients with environmental adaptations and coping strategies, clinicians may assist in optimizing sensory experiences in real life context and elevate patients' quality of life. Relating to quality of life and emphasizing a multidisciplinary approach is of major importance in broadening our understanding of health conditions and providing holistic treatment for patients.