Diabetic neuropathy: review of a surgical approach to restore sensation, relieve pain, and prevent ulceration and amputation

Pilot Study: Innovative Minimally Invasive Tarsal Tunnel Release for Diabetic Foot Ulcer Patients Minimizing Drawbacks

Background

Diabetic foot ulcers are challenging to manage due to the multifactorial nature of the disease, with diabetic neuropathy being a primary contributing factor. Tarsal tunnel release has shown promise in restoring sensation, reducing ulcer recurrence through improved sensation, and enhancing microcirculation to promote ulcer healing. However, existing open and endoscopic techniques have notable limitations. This study introduces a novel minimally invasive tarsal tunnel release technique designed to address these shortcomings.

Methods

A retrospective cohort study was conducted at Sengkang General Hospital, a tertiary care center. The control group comprised 22 consecutive patients who underwent open tarsal tunnel release, whereas the treatment group included 34 consecutive patients treated with the novel minimally invasive approach. All patients were followed up for a minimum of 3 months.

Results

Both groups demonstrated comparable efficacy in improving sensation (100% versus 95.5%) and 2-point discrimination (88.2% versus 86.4%; P = 0.19, P = 0.83, respectively). However, the treatment group exhibited significantly shorter wound lengths (2.3 ± 0.26 versus 5.8 ± 0.72 cm; P < 0.0001) and a faster wound healing duration (15 ± 5 versus 24 ± 17 d; P = 0.0052). Additionally, the treatment group experienced no major wound complications compared with a 13.6% complication rate in the control group (P = 0.029).

Conclusions

This minimally invasive novel technique demonstrates similar efficacy in improving sensation while addressing the limitations of existing open and endoscopic methods. It offers significant advantages in terms of reduced wound size, faster healing, and lower complication rates.

Dellon decompression of the tarsal tunnel: An effective approach to improving blood flow, promoting ulcer healing and recovery of sensibility in diabetic patients

We hypothesized that tibial nerve decompression would improve sympathetic nerve function, leading to increased blood flow, enhanced plantar sensitivity, and reduced healing time for diabetic neuropathic ulcers. This prospective study involved 20 patients with non-healing diabetic neuropathic ulcers averaging 17.1 months in duration. Patients had good glycemic control and positive Tinel sign at the tarsal tunnel, with average ulcer size of 10.49 cm². Preoperatively, sensory symptoms were assessed using the Michigan Neuropathy Screening Instrument (MNSI) and two-point discrimination test, ulcer characteristics using DMIST scale, and blood flow via Doppler ultrasonography of the posterior tibial artery. "Dellon Decompression" of the 4 medial ankle tunnels was performed. At the 9-month follow-up, MNSI scores decreased significantly from a mean of 11.85 to 5.15 (p < 0.001). Positivity of the Tinel sign, quantified using the visual analog scale, dropped from a mean of 7 to 2 (p < 0.0001). Significant improvements in sensory function of the medial, lateral plantar, and calcaneal nerves were observed (p < 0.001). Doppler ultrasonography showed blood flow in the posterior tibial artery increased from 1.72 to 2.48 cm³/s at 6 months, with further improvement at 9 months (p < 0.0001). At 9 months, 55% of patients had completely healed ulcers, with 45% showing an 83.25% reduction in ulcer size (p < 0.0001). No infections or new ulcers occurred postoperatively. In conclusion, Dellon decompression of the 4 medial ankle tunnels can enhance blood flow in diabetic neuropathy, improves wound healing in the foot's plantar area, and emphasizes the crucial role of enhanced blood flow and sensitivity in promoting foot ulcer healing in diabetic patients.

From Morphology to Therapeutic Strategies: Exploring New Applications of Ultrasound for Diabetic Peripheral Neuropathy Diagnosis and Management

Diabetic peripheral neuropathy (DPN) is a common complication of diabetes that can result in severe lower limb pain and amputation. Early detection and treatment of DPN are vital, but this condition is often missed due to a lack of symptoms and the insensitivity of testing methods. This article reviews various ultrasound imaging modalities in the direct and indirect evaluation of peripheral neuropathy. Moreover, how ultrasound-related therapeutic strategies are playing a role in clinical treatment is discussed. Finally, the application of innovative methodologies in the diagnosis of DPN, including ultrasound attenuation, photoacoustic imaging, and artificial intelligence, is described.

Nerve decompression for diabetic peripheral neuropathy with nerve entrapment: a narrative review

Diabetic peripheral neuropathy (DPN) is one of the most common complications of diabetes which primarily affects the sensory nervous system. Pain is the most common complaint that prompts patients to seek medical advice. With various presentations and intricate pathological mechanisms, diabetic peripheral neuropathic pain is currently the most crucial and challenging aspect of managing diabetic complications. As a heterogeneous disorder, there is no medication or treatment modality that is effective for all types of DPN and its associated neuropathic pain. Peripheral nerve decompression provides a new option for treating patients with diabetic peripheral neuropathic pain in the lower extremities. However, the clinical applicability of nerve decompression has been debated since it was first proposed. This review discusses the theoretical basis of nerve decompression, the clinical indications, and the progress of basic research based on the pathological mechanisms and nerve impairment patterns of diabetic peripheral neuropathic pain. The heterogeneity of DPN patients is summarized in terms of three aspects: complex pathophysiological mechanisms, multilevel nervous system involvement, and various nerve impairment properties. Identifying the presence of nerve entrapment among complex pathophysiological mechanisms is the key to successful outcomes. Tinel signs, focal pain, mechanical allodynia, and two-point discrimination were reported to be prognostic factors for good surgical outcomes, and their predictive ability might stem from their association with the early stage of entrapment neuropathy.

Improving Effects of Peripheral Nerve Decompression Microsurgery of Lower Limbs in Patients with Diabetic Peripheral Neuropathy

Background: Peripheral nerve decompression microsurgery can relieve nerve entrapment and improve the symptoms of DPN. However, postoperative tissue adhesion will produce new pressure on the nerves, affecting the surgical efficacy. In this study, a nerve conduit was used in the peripheral nerve decompression microsurgery to prevent postoperative adhesions, and the role of the nerve conduit in surgical nerve decompression was explored. Methods: A total of 69 patients with DPN were recruited and randomly divided into three groups: the nerve conduit group, conventional surgery group, and control group. Two weeks before surgery and 6 months after surgery, patients in each group were clinically tested using the visual analog scale (VAS) score, neurophysiological test, Toronto clinical scoring system (TCSS) score, and two-point discrimination (2-PD) test. Results: The patients’ symptoms in the nerve conduit group were relieved to varying degrees, and the relief rate reached 90.9%; the treatment efficacy was higher than that in the other groups. The postoperative nerve conduction velocity (NCV) in the two surgical groups was significantly higher than that before the surgery, and the difference between the nerve conduit group and the conventional surgery group was statistically significant (p < 0.05). For the 2-PD test, there was a statistically significant difference between the two surgical groups (p < 0.05). The TCSS score in the two surgical groups was significantly higher than that in the control group (p < 0.01). There was a significant difference in the TCSS scores between the nerve conduit group and the conventional surgery group (p < 0.05). Conclusions: The nerve conduit could further improve the efficacy of peripheral nerve decompression microsurgery in the treatment of DPN.

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.

Advances in Interventional Therapies for Painful Diabetic Neuropathy: A Systematic Review

BACKGROUND

Painful diabetic neuropathy (PDN) is one of the major complications of diabetes mellitus. It is often debilitating and refractory to pharmaceutical therapies. Our goal was to systematically review and evaluate the strength of evidence of interventional management options for PDN and make evidence-based recommendations for clinical practice.

METHODS

We searched PubMed, Scopus, Google Scholar, and Cochrane Llibrary and systematically reviewed all types of clinical studies on interventional management modalities for PDN.

RESULTS

We identified and analyzed 10 relevant randomized clinical trials (RCTs), 8 systematic reviews/meta-analyses, and 5 observational studies of interventional modalities for PDN using pain as primary outcome. We assessed the risk of bias in grading of evidence and found that there is moderate to strong evidence to support the use of dorsal column spinal cord stimulation (SCS) in treating PDN in the lower extremities (evidence level: 1B+), while studies investigating its efficacy in the upper extremities are lacking. Evidence exists that acupuncture and injection of botulinum toxin-A provide relief in pain or muscle cramps due to PDN with minimal side effects (2B+/1B+). Similar level of evidence supports surgical decompression of lower limb peripheral nerves in patients with intractable PDN and superimposed nerve compression (2B±/1B+). Evidence for sympathetic blocks or neurolysis and dorsal root ganglion (DRG) stimulation is limited to case series (2C+).

CONCLUSIONS

Moderate to strong evidence exists to support the use of SCS in managing lower extremity pain in patients who have failed conventional medical management for PDN. Acupuncture or injection of botulinum toxin-A can be considered as an adjunctive therapy for PDN. Surgical decompression of peripheral nerves may be considered in patients with PDN superimposed with nerve compression. High-quality studies are warranted to further evaluate the safety, efficacy, and cost-effectiveness of interventional therapies for PDN.

Negative pressure wound therapy, artificial skin and autogenous skin implantation in diabetic foot ulcers

OBJECTIVE

Diabetic foot ulcers (DFUs) are one of the most serious diabetic consequences, leading to amputations. Various therapies have been used to treat DFUs; however, a combination of negative pressure suction, artificial skin and autogenous skin implantation have never been investigated. This study aimed to evaluate the effectiveness of a novel three-step therapy protocol using negative pressure wound therapy (NPWT), artificial skin and autogenous skin implantation in patients with DFUs.

METHOD

At a single tertiary university hospital between 2015 and 2018, the three-step therapy protocol was applied to patients with DFUs and its safety and efficacy was investigated.

RESULTS

A total of 21 patients took part in the study. The majority of the patients were female (62%), with a mean age of 65 years and a mean body mass index of 21kg/m². A third (n=7) of operative sites experienced minor complications, with two requiring re-operation. At a median follow up of 24 months, the average time of complete wound healing was 46 days, and the wound healing rate was 71%. The first-stage wound healing rate was 90%. All patients had achieved remission without any further recurrence of disease.

CONCLUSION

This comprehensive surgical technique for managing DFUs achieved a high local cure rate, minimal functional morbidity, and acceptable wound complication rates. The three-step therapy protocol has the potential to promote the healing process of DFUs, which is expected to serve as a new method for the treatment and cure of DFUs.

Alteration of Sciatic Nerve Histology and Electrical Function After Compression and After Neurolysis in a Diabetic Rat Model

BACKGROUND

Diabetic rats are more sensitive to nerve entrapment. This study was conducted to evaluate nerve function and histological changes in diabetic rats after nerve compression and subsequent decompression.

METHODS

A total of 35 Wistar rats were included. The experimental group was divided into diabetic sciatic nerve compression group (DSNC, n = 5) and diabetic sciatic nerve decompression group (DSND, n = 20). The DSNC model was created by wrapping a silicone tube circumferentially around the nerve for 4 weeks, and then the DSND group accepted nerve decompression and was followed up to 12 weeks. The DSND group was equally divided into DSND 3 weeks (DSND3), 6 weeks (DSND6), 9 weeks (DSND9), and 12 weeks (DSND12) groups. Five rats were taken as normoglycemic control group (CR, n = 5), and another 5 rats as diabetic control group (DM, n = 5). The mechanical hyperalgesia of rats was detected by Semmes-Weinstein nylon monofilaments (SWMs) and by motor nerve conduction velocity (MNCV). These 2 physiological indicators and histology of sciatic nerves were compared among different groups.

RESULTS

The SWM measurements improved toward normal values after decompression. The SWM value was significantly lower (more normal) in the DSNC groups than in the DSND group (P < 0.05). The MNCV was 53.7 ± 0.8 m/s in the CR group, whereas it was 28.4 ± 1.0 m/s in the DSNC group (P < 0.001). Six weeks after decompression, the MNCV was significantly faster than that in the DSNC group (P < 0.001). Histological examination demonstrated chronic nerve compression, which responded toward normal after decompression, but with degree of myelination never recovering to normal.

CONCLUSIONS

Chronic compression of the diabetic sciatic nerve has measureable negative effects on sciatic nerve motor nerve function, associated with a decline of touch/pressure threshold and degeneration of myelin sheath and axon. Nerve decompression surgery can reverse these effects and partially restore nerve function.

Clinical spectra of neuromuscular manifestations in patients with lipodystrophy: A multicenter study

Lipodystrophy is a heterogeneous group of disorders characterized by loss of adipose tissue. Here, we report on clinical spectra of neuromuscular manifestations of Turkish patients with lipodystrophy. Seventy-four patients with lipodystrophy and 20 healthy controls were included. Peripheral sensorimotor neuropathy was a common finding (67.4%) in lipodystrophic patients with diabetes. Neuropathic foot ulcers were observed in 4 patients. Drop foot developed in 1 patient with congenital generalized lipodystrophy type 1. Muscle symptoms and hypertrophy were consistent findings in congenital generalized lipodystrophy (21/21) and familial partial lipodystrophy (25/34); on the other hand, overt myopathy with elevated creatine kinase activity was a distinctive characteristic of congenital generalized lipodystrophy type 4. Muscle biopsies revealed myopathic changes at different levels. Accumulation of triglycerides was observed which contributes to insulin resistance. All patients with congenital generalized lipodystrophy suffered from tight Achilles tendons at various levels. Scoliosis was observed in congenital generalized lipodystrophy type 4 (2/2) and familial partial lipodystrophy type 2 (2/17). Atlantoaxial instability was unique to congenital generalized lipodystrophy type 4 (2/2). Bone cysts were detected in congenital generalized lipodystrophy type 1 (7/10) and congenital generalized lipodystrophy type 2 (2/8). Our study suggests that lipodystrophies are associated with a wide spectrum of neuromuscular abnormalities.

Treatment of Peripheral Neuropathy in Leprosy: The Case for Nerve Decompression

Supplemental Digital Content is available in the text.

Plastic surgery has a tradition of caring for patients with facial deformity and hand deformity related to leprosy. The approach, however, to the progressive deformity and disability related to chronic nerve compression is underappreciated in the world today. A cohort of patients with leprous neuropathy from an indigenous area of leprosy in Ecuador was evaluated for the presence of chronic peripheral nerve compression, and 12 patients were chosen for simultaneous upper and lower extremity, unilateral, nerve decompression at multiple levels along the course of each nerve. The results at 1 year of follow-up show that 6 patients improved into the excellent category and 4 patients improved into the good category for improved function. Based on the early results in this small cohort of patients with leprous neuropathy, an approach to peripheral nerve decompression, encompassing the concept of multiple crush at multiple levels of each nerve, seems to offer optimism to improve upper and lower extremity limb function. Long-term studies with quality-of-life outcomes would be welcome.

The Tinel sign has no diagnostic value for nerve entrapment or neuropathy in the legs

INTRODUCTION

The presence of a Tinel sign in leg nerves has been proposed as a criterion for decompressive surgery in polyneuropathy. We investigated the diagnostic yield of the Tinel sign for nerve entrapment and for distal symmetrical peripheral neuropathy (DSPN).

METHODS

We prospectively tested for the Tinel sign at 3 sites of possible nerve entrapment per leg in 91 patients. Entrapment was defined using nerve conduction data. We also investigated whether the number of sites at which the Tinel sign was present identified patients with DSPN.

RESULTS

Sensitivity of the Tinel sign for nerve entrapment was low (29%, 44%, and 17%) for the 3 sites, and specificity was moderate (86%, 75%, and 81%). In the subgroup with DSPN, sensitivity was extremely low (0%, 20%, and 8%), and specificity was moderate (91%, 79%, and 73%). The number of sites with a Tinel sign did not identify patients with DSPN.

CONCLUSION

The Tinel sign does not reliably indicate nerve entrapment or DSPN. Muscle Nerve 54: 25-30, 2016.

Selecting a prospective test for early detection of diabetic polyneuropathy

Microneurolysis of entrapped peripheral nerve has the best chance of success when compression has not created significant axonal loss. The purpose of this study is to learn the best way to identify potential surgical candidates at the earliest time for intervention, by examining patients in a clinical setting using objective, electrodiagnostic nerve conduction studies (NCS), and subjective touch threshold studies, Semmes-Weinstein monofilaments (SWM) and Pressure-Specified Sensory Device™ (PSSD). Fifty-five patients with diabetic polyneuropathy over the age of 30 years were included. Neuropathy symptom score was the gold standard for statistical calculation, with a prevalence of 70%. In the symptomatic population, prevalence was 64% for NCS (n = 25), 59% for SWM (n = 43), and 88% for PSSD (n = 51). In the asymptomatic population, prevalence was 70% for NCS, 27% for SWM, and 92% for PSSD. It is concluded that the PSSD is the most sensitive device of those tested for identifying peripheral neuropathy in an at risk population of patients.

Low long-term risk of foot ulcer recurrence after nerve decompression in a diabetes neuropathy cohort

BACKGROUND

Use of nerve decompression in diabetic sensorimotor polyneuropathy is a controversial treatment characterized as being of unknown scientific effectiveness owing to lack of level I scientific studies.

METHODS

Herein, long-term follow-up data have been assembled on 65 diabetic patients with 75 legs having previous neuropathic foot ulcer and subsequent operative decompression of the common peroneal and tibial nerve branches in the anatomical fibro-osseous tunnels.

RESULTS

The cohort's previously reported low recurrence risk of less than 5% annually at a mean of 2.49 years of follow-up has persisted for an additional 3 years, and cumulative risk is now 2.6% per patient-year. Nine of 75 operated legs (12%) have developed an ulcer in 4,218 months (351 patient-years) of follow-up. Of the 53 contralateral legs without decompression, 16 (30%) have ulcerated, of which three have undergone an amputation. Fifty-nine percent of patients are known to be alive with intact feet a mean of 60 months after decompression.

CONCLUSIONS

The prospective, objective, statistically significant finding of a large, long-term diminution of diabetic foot ulcer recurrence risk after operative nerve decompression compares very favorably with the historical literature and the contralateral legs of this cohort, which had no decompression. This finding invites prospective randomized controlled studies for validation testing and reconsideration of the frequency and contribution of unrecognized nerve entrapments in diabetic sensorimotor polyneuropathy and diabetic foot complications.

The effect of perineurotomy on nerve regeneration in diabetic rats

BACKGROUND

One of the main causes of diabetic neuropathy is endoneurial edema, which increases the internal pressure of the perineurium, which has a tight structure. The treatment used to reduce internal pressure is perineurotomy, in which a surgical incision is made into the perineurium.

METHODS

Forty male Sprague-Dawley rats were used in the study. They were classified into four groups. Streptozotocin-induced diabetes was created in groups III and IV. The sciatic nerve was transected and repaired epineurally in all groups. Perineurotomy was performed additionally in group II and IV to the sciatic, peroneal, tibial, and sural nerves from the most proximal side to their most distal ends. The sciatic function indices were calculated for functional assessment. Light and electron microscopic evaluations were performed for morphometric assessment. In addition, the myelinated and degenerated fibers were counted in all groups.

RESULTS

The sciatic function indices of the diabetic perineurotomy group were found to be significantly higher than those of the other groups (p < 0.05). Based on the myelinated fiber counts, there was insignificant difference between group I and group II, whereas the difference was significant (p < 0.05) between group III and group IV. Presence of peripheric nerves in light microscopic evaluation revealed normal characteristics of myelinated fibers in group I and group II. The myelinated axon profile in group IV was similar to that of groups I and II in electron microscopic evaluation.

CONCLUSION

It is concluded that perineurotomy may be established as a useful adjunctive procedure for nerve repair in diabetic patients.

The Characteristics and Clinical Significance of Plantar Pressure Distribution in Patients with Diabetic Toe Deformity: A Dynamic Plantar Pressure Analysis

This study evaluated plantar pressure distribution and its clinical significance in patients with diabetic foot toe deformities. Patients with diabetic claw or hammer toe deformities (patient group; n = 30) and healthy subjects without toe deformities (control group; n = 30) were recruited into the study. Plantar pressures in different regions of the foot were measured using the F-scan® in-shoe plantar pressure dynamic analysis system. Peak pressures in the hallux and first to fifth metatarsal heads were significantly higher in the patient group compared with the control group. In the midfoot there was no significant difference between the two groups. Hindfoot peak plantar pressures were significantly lower in the patient group compared with the control group. The results indicated that toe deformities in patients with diabetes increased forefoot plantar pressures to abnormally high levels. If plantar pressure is regularly monitored in patients with diabetic foot, toe deformities might be detected earlier and ulceration prevented.

Persistent median artery: cadaveric study and review of the literature

The persistent median artery (PMA) may compress the median nerve (MN) and may be a significant supply of blood to the hand. Two cases of unilateral PMA (4%) were detected during the dissection of 50 upper limbs. The first case was a 75-year-old, right-handed male who suffered from chronic pain in both upper limbs, especially the left side. A dissection of his left upper limb revealed a PMA piercing both the MN and the medial branch of the anterior interosseous nerve. This artery coursed distally, deep to the transverse carpal ligament (TCL), forming a median-ulnar pattern for the superficial palmar arch (SPA). The PMA was superficial to two nerves at the distal edge of the TCL; the extraligamentous recurrent thenar (RT) branch of the MN and the third common digital nerve (TCDN). The second case was from the left side of an 80-year-old female found to have a high origin of the radial artery with trifurcation of the latter into PMA, common interosseous, and ulnar arteries. The PMA passed deep to the TCL forming a radial-median-ulnar pattern of SPA. Both the transligamentous RT branch of the MN and the TCDN passed deep to the PMA inside the carpal tunnel, before the abnormal crossing of the latter nerve ventral to the SPA on its way to the digits. The relationships of the PMA to various MN branches may have important implications regarding the diagnosis and treatment of MN compressive neuropathies.

Estudo comparativo da sensibilidade nos pés de diabéticos com e sem úlceras utilizando o PSSD™

INTRODUÇÃO: Determinar e comparar limiares de sensibilidade cutânea nos pés de pacientes diabéticos com úlcera em apenas um dos membros inferiores. MATERIAIS E MÉTODOS: 20 pacientes foram estudados, a média de idade e de conhecimento do diabetes foi 61,6 e 12,4 anos, respectivamente. Todos os pacientes foram previamente testados com o monofilamento de Semmes-Weinstein nº 5,07. A sensibilidade foi avaliada usando o teste de discriminação entre dois pontos e o PSSD™ (Pressure-Specified Sensory Device) para avaliar os limiares de sensibilidade de maneira quantitativa, em g/mm². Testadas três áreas da pele: polpa do hálux, dorso do pé e parte medial do calcâneo, incluindo-se quatro testes, um ponto estático, um ponto dinâmico, dois pontos estáticos e dois pontos dinâmicos. RESULTADOS: A distância média de discriminação de dois pontos em mm foi superior nos pés com úlceras, mas a diferença entre os membros inferiores teve significância estatística apenas para o hálux. Com o PSSD™, todos os pacientes tiveram limiares de pressão superior nos pés com úlcera, em comparação com os pés sem úlcera, em todos os testes e com significância estatística. CONCLUSÃO: O PSSD™ foi capaz de diferenciar níveis de sensibilidade entre membros com e sem úlcera em pacientes diabéticos, com significância estatística.

N-acetylcysteine inhibits hyperglycemia-induced oxidative stress and apoptosis markers in diabetic neuropathy

Several studies have indicated the involvement of oxidative stress in the development of diabetic neuropathy. In the present study, we have targeted oxidative stress mediated nerve damage in diabetic neuropathy using N-acetyl-l-cysteine (NAC), a potent antioxidant. After 8 weeks, streptozotocin-induced diabetic rats developed neuropathy which was evident from decreased tail-flick latency (thermal hyperalgesia). This was accompanied by decreased motor coordination as assessed by performance on rota-rod treadmill. Na(+) K(+) ATPase, a biochemical marker of development of diabetic neuropathy, was significantly inhibited in sciatic nerve of diabetic animals. NAC treatment at a daily dose between 1.4 and 1.5 g/kg body weight to diabetic animals for 7 weeks in drinking water ameliorated hyperalgesia, improved motor coordination and reversed reduction in Na(+) K(+) ATPase activity. There was an increase in lipid peroxidation in sciatic nerve of diabetic animals along with decrease in phospholipid levels, while NAC treatment attenuated lipid peroxidation and restored phospholipids to control levels. This was associated with decrease in glutathione and protein thiols. The activities of antioxidant enzymes; superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and glutathione-S-transferase were reduced in sciatic nerve of diabetic animals. Cytochrome c release and active caspase 3 were markedly increased in nerve from diabetic animals suggesting activation of apoptotic pathway. NAC treatment significantly ameliorated decrease in antioxidant defense and prevented cytochrome c release and caspase 3 activation. Electron microscopy revealed demyelination, Wallerian degeneration and onion-bulb formation in sciatic nerve of diabetic rats. NAC on the other hand was able to reverse structural deficits observed in sciatic nerve of diabetic rats. Our results clearly demonstrate protective effect of NAC is mediated through attenuation of oxidative stress and apoptosis, and suggest therapeutic potential of NAC in attenuation of diabetic neuropathy.

Revisional peripheral nerve surgery

Peripheral nerve disorders are difficult to manage. In the surgical treatment of patients with peripheral nerve pathology, there are a multitude of factors that may alter the outcome of the patient's recovery and lead to incomplete recovery or possibly worsening of symptoms. The anatomy and function of the peripheral nerve is unique and the evaluation and management of these disorders must be approached in a manner different from musculoskeletal disorders. Many anatomic areas can tolerate scar tissue and adhesions, but in peripheral nerves, loss of the gliding functional and adherence to surrounding soft tissue structures is a common complication from over-zealous dissection and repeat peripheral nerve surgery without modification of technique. The approach to each patient must be thorough and individualized to treat their specific condition, and the surgeon must be aware that at times, the most appropriate treatment for the patient may not be medical but surgical management of the chronic pain condition.

Painful diabetic neuropathy

The podiatric physician often encounters complex painful neuropathies in daily practice. Diabetic neuropathy is one form of chronic neuropathic pain dealt with on a regular basis. The goal of this article is to review the pathophysiology, diagnosis, and treatment options of this complaint. Medical and surgical interventions are discussed, with a clinical emphasis on patient selection and prevention.

Reversal of toe clawing in the patient with neuropathy by neurolysis of the distal tibial nerve

The distinction between hammer toes and clawed toes is poorly emphasized. The neural origin of clawing in the foot is related to the lateral plantar nerve, and suggests that surgical treatment directed at decompression or neurolysis of the lateral plantar nerve may either reverse or prevent progression of intrinsic motor paralysis. The purpose of this report is to provide criteria to distinguish between the musculoskeletal imbalances that creates hammer versus clawing of the toes, and to demonstrate examples of improvement in clawing that resulted from neurolysis of the tibial nerve and the lateral plantar nerve.

Clinical Outcome of Peripheral Nerve Decompression in Diabetic and Nondiabetic Peripheral Neuropathy

Surgical decompression of peripheral nerves in patients with diabetes was reported to restore sensation and improve function. In this study, a retrospective review of 12 diabetic and 20 nondiabetic patients with lower-extremity peripheral neuropathy who underwent surgical decompression was performed. Clinical evaluation by Tinel test, muscle power examination, and 2-point discrimination were performed preoperatively, at 6 months, and between 9 and 15 months postdecompression. Clinical outcomes were classified into excellent, good, or fair based on improvement in symptoms and return of function. Thirty-two patients underwent 36 surgeries, in which 99 lower-extremity nerves were decompressed. There was a statistically significant improvement in muscle function (P < 0.001) and 2-point discrimination for the small toe (P = 0.008) and big toe (P = 0.038). At a mean of 7.7 months, 90% of patients showed significant improvement in pain and function. It is concluded that surgical decompression was associated with significant improvement in clinical outcome in patients with diabetic and idiopathic neuropathy with evidence of superimposed compression.

Recent clinical advances in diabetic polyneuropathy

PURPOSE OF REVIEW

Recent dramatic increases in the incidence and prevalence of diabetes make an understanding of chronic symmetric sensorimotor diabetic polyneuropathy, the most common and problematic of chronic diabetic complications, essential for a wide range of medical practitioners.

RECENT FINDINGS

The demonstration of neuropathic dysfunction in patients with prediabetes or impaired glucose tolerance emphasizes the susceptibility of peripheral nerve fibers, especially small A delta fibers and C fibers, to relatively mild, short-duration hyperglycemia. New testing can reveal peripheral nerve dysfunction prior to clinical neuropathic symptoms and signs. In the absence of effective medications to halt or reverse nerve damage or promote nerve regeneration, early diagnosis of diabetic polyneuropathy, followed by tight glycemic control with diet and exercise, offers the best opportunity to prevent progressive symptoms of sensory loss, pain, autonomic dysfunction, ulcerations, and amputations. Some patients with impaired glucose tolerance have a reversal of neuropathic features with tight glycemic control. Nonpharmacologic therapies for neuropathic pain in diabetic polyneuropathy appear promising.

SUMMARY

Tight glycemic control, especially early in diabetes, is the best approach to minimizing the prevalence and severity of diabetic polyneuropathy and makes research into the deleterious effects of even mild hyperglycemia imperative.

Relationship between peripheral nerve decompression and gain of pedal sensibility and balance in patients with peripheral neuropathy

This was an initial exploratory study to determine if decompression of the 4 medial ankle tunnels (neurolysis of the tibial, medial and lateral plantar, and calcaneal nerves) could lead to improved foot sensibility, increased proprioception and balance, and decreased falls in a population of patients with impaired lower extremity sensation. Fourteen patients with peripheral neuropathy were included in this study. Seventy-one percent of patients were females. Average age was 67 years. All patients were evaluated preoperatively and postoperatively to assess their lower extremity sensibility, as well as their ability to stand still, maintaining their balance with their eyes open and then closed, which is defined as "sway." Lower extremity sensibility was measured with the Pressure-Specified Sensory Device (PSSD), which evaluates 1- and 2-point discrimination for the pulp of the big toe and medial heel. The MatScan Measurement System measured each patient's sway. Neuropathy was the result of diabetes in 72% of patients, a combination of diabetes and hypothyroidism in 7%, chemotherapy in 7%, and idiopathic in 14%. Eight patients underwent peripheral nerve decompression on 1 lower extremity, whereas 6 patients underwent bilateral lower extremity peripheral nerve decompression. Mean toe and heel sensibility improved 9% and 7%, respectively, in the unilateral group, whereas the bilateral group experienced an improvement in mean toe and heel sensibility of 42% (P = 0.02) and 32%, respectively. Preoperative and postoperative sway comparison in the unilateral group revealed a reduction in sway with eyes open and eyes closed by 5% and 31%, respectively. Comparison of preoperative and postoperative sway in the bilateral group showed a reduction with eyes open and eyes closed by 23% and 145% (P = 0.05), respectively. This initial study suggests that there may be benefit from bilateral lower extremity peripheral nerve decompression in helping improve pedal sensibility and balance within the peripheral neuropathy patient population, although further investigation with a larger sample size is warranted to further evaluate these preliminary findings.

Conservative treatment of peripheral neuropathy and neuropathic pain

There are many types of peripheral nerve disorders that lead to peripheral neuropathy. Symptoms associated with peripheral neuropathy lack consistent, easy to treat qualities, and provide a constant challenge for physicians who encounter the sequelae of neuropathy. This review discusses medications, nutritional supplements, and topical and physical modalities that are effective in treating neuropathy associated with diabetes.

Improved foot sensitivity and pain reduction in patients with peripheral neuropathy after treatment with monochromatic infrared photo energy--MIRE

The medical records of 2239 patients (mean age=73 years) with established peripheral neuropathy (PN) were examined to determine whether treatment with MIRE was, in fact, associated with increased foot sensitivity to the Semmes Weinstein monofilament (SWM) 5.07 and a reduction in neuropathic pain. The PN in 1395 of these patients (62%) was due to diabetes. Prior to treatment with MIRE, of the 10 tested sites (5 on each foot), 7.1+/-2.9 were insensitive to the SWM 5.07, and 2078 patients (93%) exhibited loss of protective sensation defined by Medicare as a loss of sensation at two or more sites on either foot. After treatment, the number of insensate sites on both feet decreased to 2.4+/-2.6, an improvement of 66%. Of the 2078 (93%) patients initially presenting with loss of protective sensation, 1106 (53%) no longer had loss of protective sensation after treatment (P<.0001); 1563 patients (70%) also exhibited neuropathic pain in addition to sensory impairment. Prior to treatment with MIRE, pain measured on the 11-point visual analogue scale (VAS) was 7.2+/-2.2 points, despite the use of a variety of pain-relieving therapeutic agents. After treatment with MIRE, pain was reduced by 4.8+/-2.4 points, a 67% reduction. Therefore, MIRE appears to be associated with significant clinical improvement in foot sensation and, simultaneously, a reduction in neuropathic pain in a large cohort of primarily Medicare aged, community-dwelling patients, initially diagnosed with PN. The quality of life associated with these two outcomes cannot be underappreciated.

Reversal of diabetic peripheral neuropathy with phototherapy (MIRE) decreases falls and the fear of falling and improves activities of daily living in seniors

OBJECTIVE

to determine whether restoration of sensation, impaired due to diabetic peripheral neuropathy (DPN), would reduce the number of falls and the fear of falling and improve activities of daily living (ADL) in a Medicare-aged population.

DESIGN

retrospective cohort study of patients with documented, monochromatic near-infrared phototherapy (MIRE)-mediated, symptomatic reversal of DPN.

SETTING

responses to a health status questionnaire following symptomatic reversal of DPN.

PATIENTS

252 patients (mean age 76 years) provided health information following symptomatic reversal of diabetic neuropathy (mean duration 8.6 months).

MAIN RESULTS

incidence of falls and fear of falling decreased within 1 month after reversal of peripheral neuropathy and remained low after 1 year. Likewise, improved ADL were evident soon after reversal of peripheral neuropathy and showed further improvement after 1 year. Overall, reversal of peripheral neuropathy in a clinician's office and subsequent use of MIRE at home was associated with a 78% reduction in falls, a 79% decrease in balance-related fear of falling and a 72% increase in ADL (P < 0.0002 for all results).

CONCLUSIONS

reversal of peripheral neuropathy is associated with an immediate reduction in the absolute number of falls, a reduced fear of falling and improved ADL. These results suggest that symptomatic reversal of diabetic neuropathy will have a substantial favourable, long-term socioeconomic impact on patients with DPN and the Medicare system, and improve the quality of life for elderly patients with diabetes and peripheral neuropathy.

Postarthroplasty ???Palsy??? and Systemic Neuropathy

Postarthroplasty palsy, occurrence of dysfunction of the sciatic or peroneal nerve after total joint replacement of the hip or knee, is a complication that remains poorly understood. Characteristics of a series of 24 patients with postarthroplasty palsy are reviewed, with the finding that, overall, 58.4% of the patients had an underlying peripheral neuropathy. The role of this neuropathy predisposing the arthroplasty patient to stretch/traction injury is discussed and should be emphasized as a risk factor prior to surgery and should influence the surgeon's intraoperative use of force during the arthroplasty procedure. This clinical problem is addressed from the perspective of peripheral nerve surgery, with an algorithm suggested for its management. The algorithm suggests that if a peroneal palsy is still present at 3 months after an arthroplasty and neurosensory testing fails to demonstrate a sensory reinnervation pattern in the territories of the deep or superficial peroneal nerve, then surgical neurolysis of the common peroneal nerve is indicated.