Diabetic foot ulcer: an evidence-based treatment update

Effects of different treatment measures on the efficacy of diabetic foot ulcers: a network meta-analysis

Introduction

Through a network meta-analysis, we compared different treatment measures for patients with diabetic foot ulcers (DFU), assessing their impact on the healing of DFU and ranking them accordingly.

Methods

We searched the PubMed, the China National Knowledge Infrastructure (CNKI), Embase, the WanFang and the WeiPu database. The retrieval time was from database establishment to January 2024, and retrieval entailed subject and free words. Randomized controlled trials (RCTs) with different treatment measures for DFU were included. Data extraction and evaluation were based on the PRISMA guidelines. Meta-analyses using pairwise and network methods were employed to compare and rank the effectiveness of different treatments for DFU.

Results

Ultimately, we included 57 RCTs involving a total of 4,826 patients with DFU. When it comes to ulcer healing rates, compared to standard of care(SOC),platelet-rich plasma(PRP), hyperbaric oxygen therapy(HBOT), topical oxygen therapy(TOT), acellular dermal matrix(ADM), and stem cells(SCs) in both direct meta-analysis(DMA) and network meta-analysis(NMA) can effectively increase the complete healing rate. For Scs+PRP, a statistically significant improvement was only observed in the NMA. Moreover, when compared to the negative pressure wound therapy(NPWT) group, the PRP+NPWT group was more effective in promoting the complete healing of ulcers. In terms of promoting the reduction of ulcer area, no statistical differences were observed among various treatment measures. When it comes to ulcer healing time, both PRP and NPWT can effectively shorten the healing time compared to SOC. Furthermore, when compared to the NPWT group, the combined treatment of PRP and ultrasonic debridement(UD) with NPWT is more effective in reducing healing time. In terms of amputation rates and adverse reactions, the PRP group effectively reduced the amputation rate and adverse reactions for patients with DFU. Additionally, compared to the NPWT group, the combined treatment of PRP and UD with NPWT reduced the incidence of adverse reactions. However, no significant differences were observed among other treatment measures in terms of amputation rates and adverse reactions. The ranking results showed that the efficacy of PRP+NPWT and UD+NPWT in promoting ulcer healing, reducing ulcer area, shortening healing time, decreasing amputation rates and adverse reactions is superior to that of the alone PRP group, NPWT group, and UD group. Conversely, the SOC group demonstrates the least effective performance in all aspects.

Conclusion

Due to the particularity of the wound of DFU, the standard of care is not effective, but the new treatment scheme has a remarkable effect in many aspects. And the treatment of DFU is not a single choice, combined with a variety of methods often achieve better efficacy, and will not bring more adverse reactions.

Lifestyle Medicine Approach to Wound Management

Chronic wounds impact 4.5% of the US population, necessitating a comprehensive understanding of their types and underlying mechanisms. Diabetic foot ulcers (DFUs), prevalent in 25% of individuals with diabetes, contribute significantly to lower limb amputations. The pathophysiology involves neuropathy, peripheral arterial disease, impaired immunity, glycemic control, and mechanical stress. Lifestyle medicine emerges as a pivotal aspect of care, offering both prevention and treatment by integrating plant-predominant nutrition, physical activity, stress management, avoidance of harmful substances, restful sleep, and social connectedness. These interventions impact gene interactions, immune function, and tissue regeneration, playing a crucial role in chronic wound management. The standard of care involves a multidisciplinary approach, emphasizing infection and vascular management, pressure offloading, conducive wound healing environments, and lifestyle adjustments. As diabetes prevalence rises, a proactive integration of lifestyle interventions is crucial, offering a promising avenue to alleviate the growing healthcare burden associated with chronic wounds.

Nickel-Based Metal-Organic Frameworks Promote Diabetic Wound Healing via Scavenging Reactive Oxygen Species and Enhancing Angiogenesis

Chronic diabetic wounds remain a worldwide challenge for both the clinic and research. Given the vicious circle of oxidative stress and inflammatory response as well as the impaired angiogenesis of the diabetic wound tissues, the wound healing process is disturbed and poorly responds to the current treatments. In this work, a nickel-based metal-organic framework (MOF, Ni-HHTP) with excellent antioxidant activity and proangiogenic function is developed to accelerate the healing process of chronic diabetic wounds. The Ni-HHTP can mimic the enzymatic catalytic activities of antioxidant enzymes to eliminate multi-types of reactive species through electron transfer reactions, which protects cells from oxidative stress-related damage. Moreover, this Ni-based MOF can promote cell migration and angiogenesis by activating transforming growth factor-β1 (TGF-β1) in vitro and reprogram macrophages to the anti-inflammatory phenotype. Importantly, Ni-HHTP effectively promotes the healing process of diabetic wounds by suppressing the inflammatory response and enhancing angiogenesis in vivo. This study reports a versatile and promising MOF-based nanozyme for diabetic wound healing, which may be extended in combination with other wound dressings to enhance the management of diabetic or non-healing wounds.

Concomitants of Diabetic Foot Ulcer - A Review

BACKGROUND

Diabetes mellitus leading to foot ulcer is a serious complication, and it is considered a global epidemic. Neuropathyand high blood glucose levels are the primary causes of foot ulcers. Fifteen percent of people with diabetes develop foot ulcers, and these foot disorders are the main cause of lower extremity amputation among such patients.

INTRODUCTION

Complications of diabetic foot, affecting the lower extremities are common and quite complex and life-threatening. This review focuses on the life-threatening factors associated with diabetic foot ulcers and also the diagnosing and preventive measures. Neuropathy assessment and the range of foot ulcers were accurately examined.

CONCLUSION

Novel therapies focusing on the vascularity of the lower limbs, infection control, and ischemic control are being developed to mainly treat nonhealing ulcers.

Electromechanical therapy in diabetic foot ulcers patients: A systematic review and meta-analysis

Purpose

Diabetic foot ulcer (DFU) is one of the most devastating and troublesome consequences of diabetes. The current therapies are not always effective because of the complicated aetiology and interactions of local and systemic components in DFU. However, adjunctive therapy (electromechanical therapy) has become the latest modality in recent years, although there is a lack of significant research to support its utilization as a treatment standard. The purpose of this systematic research was to review the literature on the application of electromechanical therapies in the healing of DFUs.

Methods

For this systematic review, we searched PubMed, Medline, EmBase, the Cochrane library, and Google Scholar for the most current research (1990-2022) on electromechanical therapies for DFUs. We used the PICO method (where P is population, I is intervention, C is comparator/control, and O is outcome for our study) to establish research question with the terms [Electromechanical therapy OR Laser therapy OR photo therapy OR Ultrasound therapy OR Shockwave therapy] AND [diabetic foot ulcers OR diabetes] were used as search criteria. Searches were restricted to English language articles only. Whereas, Cochrane handbook of "Systematic Reviews of Interventions" with critical appraisal for medical and health sciences checklist for systematic review was used for risk of bias assessment. There were 39 publications in this study that were deemed to be acceptable. All the suitably selected studies include 1779 patients.

Results

The meta-analysis of 15 included research articles showed the overall effect was significant (P = 0.0002) thus supporting experimental groups have improvement in the DFUs healing in comparison to the control group.

Conclusion

This systematic review and meta-analysis revealed electromechanical treatments are significantly viable options for patients with DFUs. Electromechanical therapy can considerably reduce treatment ineffectiveness, accelerate healing, and minimize the time it takes for complete ulcer healing.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01240-2.

Acellular Dermal Matrix for Treatment of Diabetic Foot Ulcer: An Overview of Systematic Reviews

Aims: To evaluate the reliability of the methodological quality and outcome measures of systematic reviews (SRs)/metaanalyses (MAs) of the acellular dermal matrix (ADM) for diabetic foot ulcer (DFU). Methods: We searched and retrieved SRs and MAs on the application of ADM for DFU from PubMed, Web of Science, The Cochrane Library, EMBASE, CNKI, CBM, WanFang, and VIP databases. We employed AMSTAR 2 to assess methodological quality, Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system to grade, and the strength of evidence of included SRs/MAs. We excluded the overlapping randomized controlled trials (RCTs) and conducted a re-MA of the primary RCTs. Results: A total of 7 SRs/MAs were included. Results from the AMSTAR 2 evaluation revealed a low overall quality; the GRADE system showed that the evidence was of moderate to very low quality. Our re-MA showed that ADM was superior to standard of care (SOC), with regards to complete wound healing rate at 12 weeks (RR = 1.74, 95% CI:1.34-2.25, P < .0001), complete wound healing rate at 16 weeks (RR = 1.50, 95% CI: 1.26-1.77, P ＜ .00001); healing time (MD = -2.06, 95% CI: -2.57 to -1.54, P < .00001) and adverse events (RR = 0.62, 95% CI: 0.49-0.80, P = .0002). However, a consensus has not yet been reached between ADM and SOC groups with regard to outcome indicators of the reduction of ulcer area and quality of life; and subgroup analyses showed no statistically significant differences between the xenograft ADM and SOC groups (RR = 1.36, 95% CI: 0.95-1.93, P = .09) at 12 weeks. Conclusion: Current evidence suggests that ADM is more effective than the standard of care in the treatment of DFU, particularly for full-thickness, noninfected, and nonischemic foot ulcers, but with low evidence quality. Therefore, the results of this overview should be interpreted dialectically and prudently, and the role of ADM in DFU needs further exploration.

Physical therapy in diabetic foot ulcer: Research progress and clinical application

Diabetes foot ulcer (DFU) is one of the most intractable complications of diabetes and is related to a number of risk factors. DFU therapy is difficult and involves long-term interdisciplinary collaboration, causing patients physical and emotional pain and increasing medical costs. With a rising number of diabetes patients, it is vital to figure out the causes and treatment techniques of DFU in a precise and complete manner, which will assist alleviate patients' suffering and decrease excessive medical expenditure. Here, we summarised the characteristics and progress of the physical therapy methods for the DFU, emphasised the important role of appropriate exercise and nutritional supplementation in the treatment of DFU, and discussed the application prospects of non-traditional physical therapy such as electrical stimulation (ES), and photobiomodulation therapy (PBMT) in the treatment of DFU based on clinical experimental records in ClinicalTrials.gov.

Human beta defensin-2 loaded PLGA nanoparticles impregnated in collagen-chitosan composite scaffold for the management of diabetic wounds

Diabetic wound (DW) is the most devastating complication resulting in significant mortality and morbidity in diabetic patients. The standard treatment of DW care fails to address the prerequisites of treating DW owing to its multifactorial pathophysiology. Henceforth, developing a single treatment strategy to handle all the loopholes may effectively manage DW. The objective of the current study was to formulate Human beta defensin-2 (HBD-2) loaded Poly (lactic-co-glycolic acid) (PLGA) nanoparticle impregnated in collagen/chitosan (COL-CS) composite scaffolds for the accelerated healing of DW. Upon investigation, the developed biodegradable crosslinked scaffold possesses low matrix degradation, optimum porosity, and sustained drug release than the non-crosslinked scaffold. In vitro studies revealed that the HBD-2 COL-CS scaffold was biocompatible and accelerated cell migration and angiogenesis. The HBD-2 COL-CS scaffold showed significant antimicrobial activity in S. aureus, E. coli, and P. aeruginosa. The in vivo studies revealed that the HBD-2 COL-CS treated group accelerated healing compared to those in COL-CS and control groups. The ELISA results indicated a significant decrease in MMP-9, TNF-α, MPO, NAG, and NO with an increase in IL-10 in HBD-2 COL-CS treated group. The accelerated healing in HBD-2 COL-CS treated group might be due to the synergistic effects of PLGA (collagen synthesis and deposition and positive angiogenic effect), HBD-2 (anti-inflammatory, antibacterial, positive angiogenic effect, cell proliferation, and migration), COL (established wound healer and stabilizer) and CS (antibacterial, controlled drug release).

Lipoic Acid Conjugated Boron Hybrids Enhance Wound Healing and Antimicrobial Processes

Complications of chronic non-healing wounds led to the emergence of nanotechnology-based therapies to enhance healing, facilitate tissue repair, and prevent wound-related complications like infections. Here, we design alpha lipoic acid (ALA) conjugated hexagonal boron nitride (hBN) and boron carbide (B₄C) nanoparticles (NPs) to enhance wound healing in human dermal fibroblast (HDFa) cell culture and characterize its antimicrobial properties against Staphylococcus aureus (S. aureus, gram positive) and Escherichia coli (E. coli, gram negative) bacterial strains. ALA molecules are integrated onto hBN and C₄B NPs through esterification procedure, and molecular characterizations are performed by using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-vis spectroscopy. Wound healing and antimicrobial properties are investigated via the use of cell viability assays, scratch test, oxidative stress, and antimicrobial activity assays. Based on our analysis, we observe that ALA-conjugated hBN NPs have the highest wound-healing feature and antimicrobial activity compared to ALA-B₄C. On the other hand, hBN, ALA-B₄C, and ALA compounds showed promising regenerative and antimicrobial properties. Also, we find that ALA conjugation enhances wound healing and antimicrobial potency of hBN and B₄C NPs. We conclude that the ALA-hBN conjugate is a potential candidate to stimulate regeneration process for injuries.

Debridement of Diabetic Foot Ulcers

Diabetic foot ulcerations have devastating complications, including amputations, poor quality of life, and life-threatening infections. Diabetic wounds can be protracted, take significant time to heal, and can recur after healing. They are costly consuming health care resources. These consequences have serious public health and clinical implications. Debridement is often used as a standard of care. Debridement consists of both nonmechanical (autolytic, enzymatic) and mechanical methods (sharp/surgical, wet to dry debridement, aqueous high-pressure lavage, ultrasound, and biosurgery/maggot debridement therapy). It is used to remove nonviable tissue, to facilitate wound healing, and help prevent these serious outcomes. What are the various forms and rationale behind debridement? This article comprehensively reviews cutting-edge methods and the science behind debridement and diabetic foot ulcers.

Histological and Molecular Evidence of the Positive Performance of Glycerol-Plasticized Chitosan-Alginate Membranes on Skin Lesions of Hyperglycemic Mice

The purpose of this study was to investigate tissue repair of excisional wounds in hyperglycemic animals treated with chitosan-alginate membranes (CAM) produced in the presence of glycerol. 8-week C57B1 male mice were divided into normoglycemic animals with a 0.9% saline solution topical treatment (CTSF); hyperglycemic animals with 0.9% saline solution topical treatment (DMSF) and hyperglycemic animals with glycerol-plasticized chitosan-alginate membrane topical treatment (DMCAM). On post-wound day three, the DMCAM group presented a lower number of leukocytes, mature mastocytes, a higher number of vessels (p < 0.05), and active mastocytes (p < 0.05) when compared to the CTSF and DMSF groups. There were no differences regarding the distribution, deposition, organization, and thickness of collagen fibers. On day 7 there were no differences in the analysis of fibroblasts, mastocytes, and TGF−β1 and VEGF expressions among the groups. Regarding collagen fibers, the DMCAM group presented slight red-orange birefringence when compared to the CTSF and DMSF groups. On day 14 there was a slight concentration of thinner elastic fibers for the DMCAM group, with a greater reorganization of papillary skin and improved red-orange birefringence collagen fibers, as well as net-shaped orientation, similar to intact skin. In addition, improved elastic fiber organization distributed in the entire neo-dermis and a larger presence of elaunin fibers were observed, in a similar pattern found in the intact skin. The use of CAM in cutaneous lesions boosted tissue repair since there was a smaller number of inflammatory cells and mastocytes, and an improvement in collagen deposition and collagen fibers. These results demonstrate the high potential of plasticized chitosan-alginate membrane for skin wound dressing of hyperglycemic patients.

Huangbai liniment and berberine promoted wound healing in high-fat diet/Streptozotocin-induced diabetic rats

Diabetic ulcer is a challenging complication of diabetes mellitus but current treatments cannot achieve satisfactory results. In this study, the effect of Huangbai liniment (HB) and berberine on the wound healing in high fat diet/streptozotocin injection induced diabetic rats was investigated by RNA-seq technology. HB topical treatment promoted wound healing in the diabetic patients and diabetic rats, and it affected multiple processes, of which IL-17 signalling pathway was of importance. Inhibiting IL-17a by its inhibitor or antibody remarkably facilitated wound healing and HB significantly repressed the high IL-17 expression and its downstream targets, including Cxcl1, Ccl2, Mmp3, Mmp9, G-CSF, IL1B and IL6, in diabetic wounds, promoted T-AOC, SOD activity and GSH levels; decreased the levels of nitrotyrosine and 8-OHdG; enhanced angiogenesis-related CD31, PDGF-BB and ANG1 expression; inhibited cleaved caspase-3 levels and promoted TIMP1 and TGFB1. Moreover, berberine (a major component in HB) repressed the IL-17 signalling pathway, and promoted wound healing in diabetes mellitus. This study highlights the strategy of targeting IL-17a in diabetic wounds, deepens the understanding of wound healing in diabetes mellitus in a dynamic way and reveals the characteristics of HB and berberine in promoting wound healing of type 2 diabetes mellitus.

Dichotomous role of miR193b-3p in diabetic foot ulcers maintains inhibition of healing and suppression of tumor formation

Despite the hyperproliferative environment marked by activation of β-catenin and overexpression of c-myc, the epidermis surrounding chronic diabetic foot ulcers (DFUs) is clinically hypertrophic and nonmigratory yet does not undergo malignant transformation. We identified miR193b-3p as a master regulator that contributes to this unique cellular phenotype. We determined that induction of tumor suppressor miR193b-3p is a unique feature of DFUs that is not found in venous leg ulcers, acute wounds, or cutaneous squamous cell carcinoma (SCC). Genomic analyses of DFUs identified suppression of the miR193b-3p target gene network that orchestrates cell motility. Inhibition of migration and wound closure was further confirmed by overexpression of miR193b-3p in human organotypic and murine in vivo wound models, whereas miR193b-3p knockdown accelerated wound reepithelialization in human ex vivo and diabetic murine wounds in vivo. The dominant negative effect of miR193b-3p on keratinocyte migration was maintained in the presence of promigratory miR31-5p and miR15b-5p, which were also overexpressed in DFUs. miR193b-3p mediated antimigratory activity by disrupting stress fiber formation and by decreasing activity of GTPase RhoA. Conversely, miR193b-3p targets that typically participate in malignant transformation were found to be differentially regulated between DFUs and SCC, including the proto-oncogenes KRAS (Kirsten rat sarcoma viral proto-oncogene) and KIT (KIT proto-oncogene). Although miR193b-3p acts as a tumor suppressor contributing to low tumor incidence in DFUs, it also acts as a master inhibitor of cellular migration and epithelialization in DFUs. Thus, miR193b-3p may represent a target for wound healing induction, cancer therapeutics, and diagnostics.

Offloading devices for neuropathic foot ulcers in adult persons with type 1 or type 2 diabetes: a rapid review with meta-analysis and trial sequential analysis of randomized controlled trials

INTRODUCTION

Healing time for neuropathic planter foot ulcers (NPFUs) in persons with diabetes may be reduced through use of non-removable fiberglass total contact casting (F-TCC) compared with removable cast walkers (RCWs), although the evidence base is still growing.

RESEARCH DESIGN AND METHODS

We conducted a rapid review and systematically searched for, and critically assessed, randomized controlled trials (RCTs) that compared the efficacy of F-TCC versus RCW, focusing on the time to ulcer healing in adult persons (18+ years) with NPFUs and type 1 or type 2 diabetes. We meta-analysed the mean differences and associated 95% CIs using an inverse variance, random-effects model. We also conducted a trial sequential analysis (TSA) to assess if the available evidence is up to the required information size for a robust conclusion. We assessed and quantified statistical heterogeneity between the included studies using the I² statistic.

RESULTS

Out of 102 retrieved citations, five RCTs met the eligibility criteria. Participants' inclusion in relation to stage of ulcer was highly variable as was peripheral neuropathy complicating comparisons. F-TCC appeared to present a shorter ulcer healing time (-5.42 days, 95% CI -9.66 days to -1.17 days; I² 9.9%; 5 RCTs; 169 participants) compared with RCW. This finding was supported by the TSA.

CONCLUSIONS

There is limited evidence from RCTs to suggest that F-TCC has a shorter ulcer healing time compared with RCW among adults with diabetic NPFUs. Properly designed and conducted RCTs are still required for a stronger evidence base.

Clinical Study on the Efficacy of Silver Ion Dressing Combined with Prontosan Gel Dressing in the Treatment of Diabetic Foot Ulcers and the Effect on Serum Inflammatory Factors

Diabetic foot ulcers (DFUs) have a high disability rate and have a great impact on patients and society, and the search for effective and economical treatment options is a major clinical concern. In this study, 112 patients with DFU admitted to two hospitals from October 2018 to November 2020 were randomly divided into 56 cases each in the single group treated with Prontosan gel dressing and the joint group treated on silver ion dressing combined with Prontosan gel dressing. Both groups of patients were evaluated for efficacy after 30 days of treatment. The number of days for debridement, granulation tissue growth time, epithelial tissue formation time, and wound healing time were observed and recorded in both groups. The trauma area, visual analogue score (VAS), and levels of inflammatory factors such as vascular endothelial adhesion molecule-1 (VCAM-1), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP) were recorded before and after treatment in both groups. The occurrence of adverse reactions such as edema, fever, infection, and rash during treatment was recorded in both groups for safety assessment. Comparison of the abovementioned data showed that the clinical efficacy of the joint group was significantly higher than that of the single group. The number of days to clear wounds, granulation tissue growth time, epithelial tissue formation time, and wound healing time were significantly lower in the joint group than in the single group. The trauma area, VAS score, VCAM-1, IL-6, TNF-α, and CRP levels decreased in both groups after treatment compared with the pretreatment levels, with the joint group being lower than the single group. The results also showed that the difference in the overall incidence of adverse reactions between the two groups was not statistically significant, and the incidence was low and transient. In addition to the usual treatment regimen of blood glucose control and improvement of microcirculation for patients with DFU, combined treatment with silver ionomer dressings and Prontosan gel dressings can promote ulcer healing and improve foot wound regression. It has a stronger antibacterial effect and can more effectively reduce the inflammatory response of the ulcerated surface with fewer adverse effects, making it an effective and safe method for the treatment of DFU, and has implications for promotion.

Consensus on the application of negative pressure wound therapy of diabetic foot wounds

Because China is becoming an aging society, the incidence of diabetes and diabetic foot have been increasing. Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates. Negative pressure wound therapy (NPWT) is one of the most effective techniques for the treatment of diabetic foot wounds and great progress, both in terms of research and its clinical application, has been made in the last 20 years of its development. However, due to the complex pathogenesis and management of diabetic foot, irregular application of NPWT often leads to complications, such as infection, bleeding and necrosis, that seriously affect its treatment outcomes. In 2020, under the leadership of Burns, Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association, the writing group for ‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’ was established with the participation of scholars from the specialized areas of burns, endocrinology, vascular surgery, orthopedics and wound repair. Drawing on evidence-based practice suggested by the latest clinical research, this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot. The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.

A small molecule HIF-1α stabilizer that accelerates diabetic wound healing

Impaired wound healing and ulcer complications are a leading cause of death in diabetic patients. In this study, we report the design and synthesis of a cyclometalated iridium(III) metal complex 1a as a stabilizer of hypoxia-inducible factor-1α (HIF-1α). In vitro biophysical and cellular analyses demonstrate that this compound binds to Von Hippel-Lindau (VHL) and inhibits the VHL-HIF-1α interaction. Furthermore, the compound accumulates HIF-1α levels in cellulo and activates HIF-1α mediated gene expression, including VEGF, GLUT1, and EPO. In in vivo mouse models, the compound significantly accelerates wound closure in both normal and diabetic mice, with a greater effect being observed in the diabetic group. We also demonstrate that HIF-1α driven genes related to wound healing (i.e. HSP-90, VEGFR-1, SDF-1, SCF, and Tie-2) are increased in the wound tissue of 1a-treated diabetic mice (including, db/db, HFD/STZ and STZ models). Our study demonstrates a small molecule stabilizer of HIF-1α as a promising therapeutic agent for wound healing, and, more importantly, validates the feasibility of treating diabetic wounds by blocking the VHL and HIF-1α interaction.

Photobiomodulation in diabetic wound healing: A review of red and near-infrared wavelength applications

The development of a painless, non-invasive, and faster way to diabetic wound healing is at the forefront of research. The complexity associated with diabetic wounds makes it a cause for concern amongst diabetic patients and the world at large. Irradiation of cells generates a photobiomodulatory response on cells and tissues, directly causing alteration of cellular processes and inducing diabetic wound repair. Photobiomodulation therapy (PBMT) using red and near-infrared (NIR) wavelengths is being considered as a promising technique for speeding up the rate of diabetic wound healing, eradication of pain and reduction of inflammation through the alteration of diverse cellular and molecular processes. This review presents the extent to which the potential of red and NIR wavelengths have been harnessed in PBMT for diabetic wound healing. Important research challenges and gaps are identified and discussed, and future directions mapped out. This review thus provides useful insights and strategies into improvement of PBMT, including its acceptance within the global medical research community.

A Meta-Analysis of the Outcomes of Metatarsal Head Resection for the Treatment of Neuropathic Diabetic Foot Ulcers

Significance: Diabetic foot ulcers (DFUs) are associated with high morbidity, mortality, and health costs. Standard care (SC) associated with nonsurgical offloading is the mainstay treatment for DFUs, but it has high recurrence and infection rates. Metatarsal head resection (MHR) has been proposed as an effective surgical offloading technique for the treatment of plantar neuropathic DFUs, but with no evidence synthesis yet. Recent Advances: Based on PRISMA guidelines, a meta-analysis was conducted to assess the efficacy of MHR. Four electronic databases were searched for. Eleven studies met the inclusion criteria with a total of 477 patients (494 feet and 593 neuropathic forefoot ulcers). The studies included three retrospective comparative studies and eight case series. Critical Issues: Meta-analytical results of comparative studies on recent noninfected DFUs showed MHR having significantly better rates of healing, time to healing, ulcer recurrence, and infection than SC. Failure to heal, recurrence, and infection rates were 4 times higher in the SC group than in the MHR group, and the amputation rate was two times higher in the SC group than in the MHR group. The outcomes of the meta-analysis of case series on chronic and recalcitrant ulcers treated with MHR were similar. Future Directions: Considering the natural history of DFUs treated conservatively and the satisfactory outcomes with a significantly low complication rate of MHR, physicians should consider the use of MHR more often and include this technique in the early management of DFUs. Scope and Significance: DFU impose great public health burden around the globe. Standard of care using in-office debridement and topical agents is the usual mainstay of treatment. However, such conservative care is known to result in high rates of ulcer recurrence and complications. In this systematic review, we quantitatively investigate the outcomes of a surgical off-loading technique, the MHR in the treatment of chronic plantar neuropathic wounds. Translational Relevance: Many biochemical factors are implicated in the complex process of wound healing. In the case of diabetic neuropathic ulcers of the forefoot, additional mechanical factors induced by the presence of diabetic neuropathy lead to high pressure loads of the metatarsal heads on the plantar skin. With time, such chronic loads could favor ulcer formation. Removal of the causal mechanical factor could alleviate the pressure and allow wound healing. Clinical Relevance: Neuropathic plantar ulcers are difficult-to-heal wounds and chronicity is associated to frequent hospitalizations, higher rates of amputation, and mortality. Early removal of the indirect causal agent, the resection of the metatarsal head, after failure of a well-conducted conservative standard of care could be a needed solution for wound healing and consequently a potential for reducing complications and costs.

Improving Chronic Diabetic Wound Healing through an Injectable and Self-Healing Hydrogel with Platelet-Rich Plasma Release

Diabetic skin ulcer is one of the severe complications of diabetes mellitus, which has a high incidence and may cause death or disability. Platelet-rich plasma (PRP) is widely used in the treatment of diabetic wounds due to the effect of growth factors (GFs) derived from it. However, the relatively short half-life of GFs limits their applications in clinics. In addition, the presence of a large amount of proteases in the diabetic wound microenvironment results in the degradation of GFs, which further impedes angiogenesis and diabetic wound healing. In our study, we fabricated a self-healing and injectable hydrogel with a composite of chitosan, silk fibroin, and PRP (CBPGCTS-SF@PRP) for promoting diabetic wound healing. CBPGCTS-SF@PRP could protect PRP from enzymatic hydrolysis, release PRP sustainably, and enhance the chemotaxis of mesenchymal stem cells. The results showed that it could promote the proliferation of repair cells in vitro. Moreover, it could enhance wound healing by expediting collagen deposition, angiogenesis, and nerve repair in a type 2 diabetic rat model and a rat skin defect model. We hope that this study will offer a new treatment for diabetic nonhealing wounds in clinics.

Nonpharmacological Management of Diabetic Foot Ulcers: An Update

Diabetic foot ulcers (DFUs) are a common and serious complication of diabetes mellitus that is associated with increased morbidity and mortality, as well as substantial economic burden for the health care system. The standard of care for DFUs includes pressure off-loading, sharp debridement, and wound moisture balance, along with infection control and management of peripheral arterial disease. A variety of advanced modalities that target distinct pathophysiological aspects of impaired wound healing in diabetes are being studied as possible adjunct therapies for difficult to heal ulcers. These modalities include growth factors, stem cells, cultured fibroblasts and keratinocytes, bioengineered skin substitutes, acellular bioproducts, human amniotic membranes, oxygen therapy, negative pressure wound therapy, and energy therapies. Additionally, the use of advanced biomaterials and gene delivery systems is being investigated as a method of effective delivery of substances to the wound bed. In the present narrative review, we outline the latest advances in the nonpharmacological management of DFUs and summarize the efficacy of various standard and advanced treatment modalities.

What Makes Wounds Chronic

Chronic wounds present a unique therapeutic challenge to heal. Chronic wounds are colonized with bacteria and the presence of a biofilm that further inhibits the normal wound healing processes, and are locked into a very damaging proinflammatory response. The treatment of chronic wounds requires a coordinated approach, including debridement of devitalized tissue, minimizing bacteria and biofilm, control of inflammation, and the use of specialized dressings to address the specific aspects of the particular nonhealing ulcer.

Electrospun cellulose acetate/gelatin nanofibrous wound dressing containing berberine for diabetic foot ulcer healing: in vitro and in vivo studies

Functional wound dressing with tailored physicochemical and biological properties is vital for diabetic foot ulcer (DFU) treatment. Our main objective in the current study was to fabricate Cellulose Acetate/Gelatin (CA/Gel) electrospun mat loaded with berberine (Beri) as the DFU-specific wound dressing. The wound healing efficacy of the fabricated dressings was evaluated in streptozotocin-induced diabetic rats. The results demonstrated an average nanofiber diameter of 502 ± 150 nm, and the tensile strength, contact angle, porosity, water vapor permeability and water uptake ratio of CA/Gel nanofibers were around 2.83 ± 0.08 MPa, 58.07 ± 2.35°, 78.17 ± 1.04%, 11.23 ± 1.05 mg/cm2/hr, and 12.78 ± 0.32%, respectively, while these values for CA/Gel/Beri nanofibers were 2.69 ± 0.05 MPa, 56.93 ± 1°, 76.17 ± 0.76%, 10.17 ± 0.21 mg/cm2/hr, and 14.37 ± 0.42%, respectively. The antibacterial evaluations demonstrated that the dressings exhibited potent antibacterial activity. The collagen density of 88.8 ± 6.7% and the angiogenesis score of 19.8 ± 3.8 obtained in the animal studies indicate a proper wound healing. These findings implied that the incorporation of berberine did not compromise the physical properties of dressing, while improving the biological activities. In conclusion, our results indicated that the prepared mat is a proper wound dressing for DFU management and treatment.

Mevastatin promotes healing by targeting caveolin-1 to restore EGFR signaling

Diabetic foot ulcers (DFUs) are a life-threatening disease that often results in lower limb amputations and a shortened life span. Current treatment options are limited and often not efficacious, raising the need for new therapies. To investigate the therapeutic potential of topical statins to restore healing in patients with DFUs, we performed next-generation sequencing on mevastatin-treated primary human keratinocytes. We found that mevastatin activated and modulated the EGF signaling to trigger an antiproliferative and promigratory phenotype, suggesting that statins may shift DFUs from a hyperproliferative phenotype to a promigratory phenotype in order to stimulate healing. Furthermore, mevastatin induced a migratory phenotype in primary human keratinocytes through EGF-mediated activation of Rac1, resulting in actin cytoskeletal reorganization and lamellipodia formation. Interestingly, the EGF receptor is downregulated in tissue biopsies from patients with DFUs. Mevastatin restored EGF signaling in DFUs through disruption of caveolae to promote keratinocyte migration, which was confirmed by caveolin-1 (Cav1) overexpression studies. We conclude that topical statins may have considerable therapeutic potential as a treatment option for patients with DFUs and offer an effective treatment for chronic wounds that can be rapidly translated to clinical use.

An MMP/TIMP ratio scoring system as a potential predictive marker of diabetic foot ulcer healing

OBJECTIVES

The mechanism of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in diabetic foot ulcers (DFUs) is unclear. The purpose of this study was to describe changes in MMP-1, MMP-9, and TIMP-1 levels during DFU healing, and to search for any correlation in the changes in MMP levels with wound healing, in order to find possible predictors of healing.

METHODS

Patients with a DFU were recruited and placed into two groups, according to the degree of wound healing: 'good healers' and 'poor healers'. Levels of MMP-1, MMP-9, and TIMP-1 were analysed by ELISA (enzyme-linked immunosorbent assay).

RESULTS

A total of 22 patients participated in the study. The MMP-1 level was significantly higher at weeks zero (W0) and 12 (W12) in 'good healers' than in 'poor healers' (p=0.045 and 0.008, respectively). In contrast, the MMP-9 level was significantly lower in 'good healers' than in 'poor healers' at W0, W4, and W12 (p=0.001, 0.001 and 0.028, respectively). Receiver operator curve (ROC) analysis of the MMP-9 level, MMP-1/TIMP-1 ratio, and MMP-9/TIMP-1 ratio at W0 provided cut-off levels of 0.38, 0.056, and 9.06, respectively, which were best predictive of a reduction in wound area at W4 ('good healers' versus 'poor healers'; thereby predicting wound healing condition at W12) with a sensitivity of 81.8%, 81.8%, and 90.9%, and a specificity of 64.6%, 55%, and 64.6%, respectively.

CONCLUSION

A 'poor healing scoring system' is therefore proposed that could be determined on patient admission, which has the potential to be used clinically as a predictor of healing, thus allowing an appropriate treatment plan to be developed.

Bioinorganics and Wound Healing

Wound dressings and the healing enhancement (increasing healing speed and quality) are two components of wound care that lead to a proper healing. Wound care today consists mostly of providing an optimal environment by removing waste and necrotic tissues from a wound, preventing infections, and keeping the wounds adequately moist. This is however often not enough to re-establish the healing process in chronic wounds; with the local disruption of vascularization, the local environment is lacking oxygen, nutrients, and has a modified ionic and molecular concentration which limits the healing process. This disruption may affect cellular ionic pumps, energy production, chemotaxis, etc., and will affect the healing process. Biomaterials for wound healing range from simple absorbents to sophisticated bioactive delivery vehicles. Often placing a material in or on a wound can change multiple parameters such as pH, ionic concentration, and osmolarity, and it can be challenging to pinpoint key mechanism of action. This article reviews the literature of several inorganic ions and molecules and their potential effects on the different wound healing phases and their use in new wound dressings.

Bioadhesive functional hydrogels: Controlled release of catechol species with antioxidant and antiinflammatory behavior

Chronic wounds are particularly difficult to heal and constitute an important global health care problem. Some key factors that make chronic wounds challenging to heal are attributed to the incessant release of free radicals, which activate the inflammatory system and impair the repair of the wound. Intrinsic characteristics of hydrogels are beneficial for wound healing, but the effective control of free radical levels in the wound and subsequent inflammation is still a challenge. Catechol, the key molecule responsible for the mechanism of adhesion of mussels, has been proven to be an excellent radical scavenger and anti-inflammatory agent. Our approach in this work lies in the preparation of a hybrid system combining the beneficial properties of hydrogels and catechol for its application as a bioactive wound dressing to assist in the treatment of chronic wounds. The hydrogel backbone is obtained through a self-covalent crosslinking between chitosan (Ch) and oxidized hyaluronic acid (HAox) in the presence of a synthetic catechol terpolymer, which is subsequently coordinated to Fe to obtain an interpenetrated polymer network (IPN). The structural analysis, catechol release profiles, in vitro biological behavior and in vivo performance of the IPN are analyzed and compared with the semi-IPN (without Fe) and the Ch/HAox crosslinked hydrogels as controls. Catechol-containing hydrogels present high tissue adhesion strength under wet conditions, support growth, migration and proliferation of hBMSCs, protect cells against oxidative stress damage induce by ROS, and promote down-regulation of the pro-inflammatory cytokine IL-1β. Furthermore, in vivo experiments reveal their biocompatibility and stability, and histological studies indicate normal inflammatory responses and faster vascularization, highlighting the performance of the IPN system. The novel IPN design also allows for the in situ controlled and sustained delivery of catechol. Therefore, the developed IPN is a suitable ECM-mimic platform with high cell affinity and bioactive functionalities that, together with the controlled catechol release, will enhance the tissue regeneration process and has a great potential for its application as wound dressing.

NPWT: a gate of hope for patients with diabetic foot ulcers

Non-healing diabetic foot ulcers are a common and costly complication of type 2 diabetes and can result in lower extremity amputation. This case study concerns a 51-year-old man with a 17-year history of uncontrolled type 2 diabetes. He had developed a deep ulcer to the calcaneus of his left foot, which was 12x7 cm in size and infected with multi-drug-resistant Staphylococcus aureus. He was admitted to hospital for the non-healing diabetic foot ulcer and uncontrollable fever and was a candidate for amputation. He was treated with wound irrigation and debridement as well as negative-pressure wound therapy and antibiotic treatment. This strategy was effective and the wound size reduced progressively. The patient recovered well. Medical and wound care teams who deal with non-healing diabetic foot ulcers can benefit from a strategy of combination therapy.

Management of infected diabetic wound: a scoping review of guidelines

Background: Various international guidelines and recommendations are available for management of diabetic foot infections. We present a review of the guidelines and recommendations for management of these infections.

Methods: A systematic literature search was conducted through MEDLINE, CENTRAL, EMBASE, LILACS, DARE, and national health bodies. Based on the review of fifteen documents, we present details on the importance of suspecting and diagnosing skin, superficial infections, and bone infections in diabetics.

Results: The guidelines recommend classifying the infections based on severity to guide the treatment. While antibiotics have shown the best results, other treatments like hyperbaric oxygen therapy and negative wound pressure have been debated. It is suggested that a team of specialists should be in-charge of managing the infected wounds. Infectious Diseases Society of America (IDSA) 2012 guidelines are widely followed world-over. All guidelines and reviews have consistent suggestions on the assessment of the severity of infection, diagnosis, start, selection, and duration of antibiotic therapy.

Conclusions: It is reasonable to conclude that the IDSA 2012 guidelines are commonly followed across the world. There is a consensus among the Australian guidelines, Canadian guidelines, IDSA 2012, National Institute for Health and Care Excellence (NICE) 2015, and International Working Group on the Diabetic Foot (IWGDF) 2016 guidelines on the management of infected wounds for patients with diabetes mellitus.

Advancing pharmacotherapy for diabetic foot ulcers

INTRODUCTION

Standard treatment for diabetic foot ulcers (DFUs) includes off-loading, debridement, moisture balance, management of infection and peripheral arterial disease (PAD) as well as adequate glycemic control. The outcomes so far are unsatisfactory.

AREAS COVERED

Herein, the authors provide an outline of newer pharmacological agents for the management of DFUs and give their expert perspectives on future treatment strategies.

EXPERT OPINION

Evidence-based healthcare calls for high quality evidence from large RCTs before the implementation of new guidelines for the management of DFUs. Empagliflozin and liraglutide can be recommended for glucose control in patients with DFUs and PAD, while intensive lipid lowering therapy with evolocumab when primary cholesterol goals are not met could be offered to patients with DFUs. Further clinical studies are warranted to develop a structured algorithm for the treatment of DFUs that fail to heal after four weeks of current standard of care. Sucrose octasulfate dressings, becaplermin gel, and platelet-rich plasma (PRP) could also be considered as advanced treatment options for the management of hard to heal DFUs.

Effect of negative-pressure wound therapy on the circulating number of peripheral endothelial progenitor cells in diabetic patients with mild to moderate degrees of ischaemic foot ulcer

Objective

To investigate the effect of negative-pressure wound therapy (NPWT) on the circulating number of endothelial progenitor cells (EPCs) in diabetic patients with mild to moderate degrees of ischemic foot ulcer.

Methods

We selected 84 diabetic patients who had a foot ulcer with a duration of at least four weeks and who had an ankle-brachial index of 0.5–0.9. Patients were assigned to one two groups according to 2:1 randomization: NPWT group ( n = 56) and non-NPWT (patients who did not receive NPWT) group ( n = 28). The control group (NC group) was composed of 18 patients who had normal glucose tolerance and lower extremity ulcer without arteriovenous disease. NPWT was performed on the ulcer after debridement for one week for patients in both the NPWT group and the NC group, and the patients in the non-NPWT group received conventional treatment process. The circulating number of EPCs was measured before and after various treatments, and the factors influencing their changes were analysed.

Results

After NPWT, the circulating number of EPCs significantly increased in both the NPWT group and the NC group ((85.3 ± 18.1) vs. (34.1 ± 12.5)/106 cells; (119.9 ± 14.4) vs. (66.1 ± 10.6)/106 cells, both P < 0.05). In contrast, the circulating number of EPCs had no significant change in the non-NPWT group ((45.2 ± 19.4) vs. (34.7 ± 16.8)/106 cells, P > 0.05). In addition, the circulating levels of vascular endothelial growth factor (VEGF) and the protein expressions of VEGF and stromal cell-derived factor-1α (SDF-1α) in the granulation tissue significantly increased after NPWT in both the NPWT and the NC group, but there was no significant change in the non-NPWT group. Compared with the non-NPWT group, the changes in VEGF and SDF-1α levels in the sera and granulation tissue were all significantly higher in both the NPWT and NC groups ( P < 0.05, P < 0.01, respectively). There was no significant difference in changes in the circulating number of EPCs in the peripheral blood and levels of VEGF and SDF-1α in the sera and granulation tissue between the NPWT and NC groups. Correlation analysis showed that the change in the circulating number of EPCs was correlated with the changes of VEGF and SDF-1α levels in the sera and granulation of the NPWT and NC groups ( P < 0.05).

Conclusion

NPWT may increase the circulating number of EPCs in diabetic patients with mild to moderate ischaemic foot ulcer as in non-diabetic controls, which may be attributed to the upregulation of systemic and local VEGF and SDF-1α levels.

Prospective Randomized Controlled Study of Hemostatic Efficacy with Kaolin-Impregnated Dressings in Diabetic Foot Ulcers Taking Anticoagulants Undergoing Debridement in an Outpatient Clinic

BACKGROUND

The effective hemostasis after minor debridement in an outpatient clinic is important and essential. This study is aimed at evaluating the hemostatic efficacy and safety of the kaolin-impregnated dressing for diabetic foot ulcer patient who take an anticoagulant.

METHODS

A prospective, randomized, clinical trial study was performed in twenty-six patients with diabetic foot ulcers who take an anticoagulant requiring minor debridement in an outpatient clinic. Minor debridement and removal of break down skin were performed by one orthopedic surgeon. Hemostasis on wound bed was achieved using kaolin-impregnated gauze (study group) and standard sterilized dry gauze (control group). Two randomized groups were compared for hemostatic efficacy and side effect.

RESULTS

For the purpose of this study, the presence or absence of hemostasis was assessed at 5 and 10 minutes after the application of dressing material. Treatment was evaluated as successful if bleeding was ceased adequately, and no extra hemostatic measures were required within 10 minutes. At 5 minutes, 80% of patients using the kaolin-impregnated gauze successfully achieved complete hemostasis versus 40% in the control group that controlled bleeding partially. With kaolin-impregnated gauze, 100% of patients show complete hemostasis at 10 minutes versus 58.3% in the standard gauze (P < .001). An adverse effect was not noted in all patients.

CONCLUSIONS

The use of kaolin-impregnated gauze appears to be a safe and feasible option in managing bleeding after debridement of diabetic foot ulcers, and merits to patient who had a bleeding tendency is high. This trial is registered with CRIS registration number KCT0003894.

Advancements in improving health-related quality of life in patients living with diabetic foot ulcers

INTRODUCTION

Diabetic foot ulcer (DFU) constitutes a burden to patients with diabetes deteriorating their quality of life. Health related quality of life (HRQoL) can now be quantified with the use of specific tools; some of them provide a holistic approach to patients' well-being, while others are disease specific or even region specific. Many of these tools are applicable to patients with DFU. This review will present current data about the impact different interventions in the management of DFU on quality of life related parameters.

AREAS COVERED

We performed a search of literature using keywords 'diabetes mellitus', 'diabetic foot ulcer', 'diabetic foot', 'health related quality of life', 'quality of life' and 'SF-36' to identify studies that contained data about the relationship between different interventions and quality of life of patients with diabetic foot ulcers.

EXPERT COMMENTARY

Available data are not sufficient to conclude on the impact of interventions aimed to heal DFU on HRQoL. There is need for more, better designed studies and meta-analysis to estimate the effect of treatments on HRQoL in patients with DFUs. The development of new, diabetic foot specific tools will help to improve our knowledge in this field.

Current concepts for the evaluation and management of diabetic foot ulcers

The lifetime risk for diabetic patients to develop a diabetic foot ulcer (DFU) is 25%. In these patients, the risk of amputation is increased and the outcome deteriorates.More than 50% of non-traumatic lower-extremity amputations are related to DFU infections and 85% of all lower-extremity amputations in patients with diabetes are preceded by an ulcer; up to 70% of diabetic patients with a DFU-related amputation die within five years of their amputation.Optimal management of patients with DFUs must include clinical awareness, adequate blood glucose control, periodic foot inspection, custom therapeutic footwear, off-loading in high-risk patients, local wound care, diagnosis and control of osteomyelitis and ischaemia. Cite this article: EFORT Open Rev 2018;3:513-525. DOI: 10.1302/2058-5241.3.180010.

Bioactive and Bioadhesive Catechol Conjugated Polymers for Tissue Regeneration

The effective treatment of chronic wounds constitutes one of the most common worldwide healthcare problem due to the presence of high levels of proteases, free radicals and exudates in the wound, which constantly activate the inflammatory system, avoiding tissue regeneration. In this study, we describe a multifunctional bioactive and resorbable membrane with in-built antioxidant agent catechol for the continuous quenching of free radicals as well as to control inflammatory response, helping to promote the wound-healing process. This natural polyphenol (catechol) is the key molecule responsible for the mechanism of adhesion of mussels providing also the functionalized polymer with bioadhesion in the moist environment of the human body. To reach that goal, synthesized statistical copolymers of N-vinylcaprolactam (V) and 2-hydroxyethyl methacrylate (H) have been conjugated with catechol bearing hydrocaffeic acid (HCA) molecules with high yields. The system has demonstrated good biocompatibility, a sustained antioxidant response, an anti-inflammatory effect, an ultraviolet (UV) screen, and bioadhesion to porcine skin, all of these been key features in the wound-healing process. Therefore, these novel mussel-inspired materials have an enormous potential for application and can act very positively, favoring and promoting the healing effect in chronic wounds.

Platelet rich plasma and growth factors cocktails for diabetic foot ulcers treatment: State of art developments and future prospects

Current advances in diabetic foot ulcers (DFU) treatment are discussed. Normal and pathological wound healing process are observed and the role of growth factors (GFs) is elucidated. Current techniques involving GFs and platelet rich plasma (PRP) are compared. Up-to-date research suggests that treatment with single growth factor (GF) could be insufficient and not encompassing all pathological changes in DFU bed. Efficiency of PRP is rather controversial and lacks evidence. Thus the use of cocktail of particular GFs is suggested. Pro et contra of each approach are discussed.

Comparison of Metatarsal Head Resection Versus Conservative Care in Treatment of Neuropathic Diabetic Foot Ulcers

Complications from diabetic foot ulcers often lead to increased patient morbidity. Much debate still ensues concerning surgical versus conservative management of neuropathic diabetic foot ulcerations. The present study assessed and compared the efficacy of metatarsal head resection and medical approach in the treatment of neuropathic diabetic foot ulcers located at the plantar surface of metatarsal heads. In a retrospective cohort study, 24 consecutive neuropathic diabetic foot ulcers in the lower area of the metatarsal heads that had undergone metatarsal head resection were included as the operative group. For the control group, we included 25 similar ulcers that were scheduled for medical therapy. With respect to postoperative complications, wound healing occurred earlier in the operative group, and the recurrence rate was inversely greater in the medical treatment group. Also, the hospitalization rate was significantly greater in the medical treatment group. Overall, the long-term complication rate was lower in the operative than in the medical treatment group. Also, the infection rate was greater in the medical treatment group than in the operative group. Comparing early and late clinical outcomes of metatarsal head resection surgery and medical treatment showed complete superiority for the surgical approach, and metatarsal head resection is more completely cost beneficial than the medical approach.

Dysfunctional Wound Healing in Diabetic Foot Ulcers: New Crossroads

PURPOSE OF REVIEW

Diabetic foot ulcerations (DFU) affect 25% of patients with diabetes mellitus during their lifetime and constitute a major health problem as they are often recalcitrant to healing due to a constellation of both intrinsic and extrinsic factors. The purpose of this review is to (1) detail the current mechanistic understanding of DFU formation and (2) highlight future therapeutic targets.

RECENT FINDINGS

From a molecular perspective, DFUs exhibit a chronic inflammatory predisposition. In addition, increased local hypoxic conditions and impaired cellular responses to hypoxia are pathogenic factors that contribute to delayed wound healing. Finally, recent evidence suggests a role for epigenetic alterations, including microRNAs, in delayed DFU healing due to the complex interplay between genes and the environment. In this regard, notable progress has been made in the molecular and genetic understanding of DFU formation. However, further studies are needed to translate preclinical investigations into clinical therapies.

Efficacy of combined treatment with vacuum sealing drainage and recombinant human epidermal growth factor for refractory wounds in the extremities and its effect on serum levels of IL-6, TNF-α and IL-2

The objective of this study was to investigate the efficacy of combined treatment with vacuum sealing drainage (VSD) and recombinant human epidermal growth factor (rhEGF) for refractory wounds in the extremities, and its effect on serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and IL-2. Ninety-eight patients with refractory wounds in the extremities were recruited and randomly divided into the combined treatment group (underwent VSD and rhEGF treatment) and control group (underwent VSD only) with 49 cases each. Formation of granulation tissue on the wound surface was assessed and scored. The wound healing rate was calculated after 1 week of treatment, and the time of complete healing was recorded. Serum levels of IL-6, IL-2, and TNF-α were measured using enzyme-linked immunosorbent assay. After 1 week of treatment, granulation tissue formation on wound surfaces was significantly improved (p<0.05) compared with that before treatment in both groups. Moreover, granulation tissue formation on wound surfaces was superior in the combined treatment group than in the control group (p<0.05). The wound healing rate was 63.50±4.75% in the combined treatment group and 31.79±3.52% in the control group, and the difference was statistically significant (p<0.05). The time of complete healing was 15.11±2.24 days in the combined treatment group and 19.63±2.76 days in the control group, and the difference was statistically significant (p<0.05). The serum levels of IL-6, IL-2, and TNF-α, in the two groups were significantly lower than those before treatment (p<0.05). Moreover, the levels in the combined treatment group were significantly lower than those in the control group (p<0.05). In conclusion, combined treatment with VSD and rhEGF reduced inflammation and shortened the time of complete healing of refractory wounds in the extremities. Measurement of the levels of related inflammatory factors provided a reference for the prognosis of refractory wounds.

How common are foot problems among individuals with diabetes? Diabetic foot ulcers in the Dutch population

AIMS/HYPOTHESIS

Contemporary data on diabetic foot ulcer prevalence are scarce. Most studies were conducted in the 1990s, reporting incidence rates of 1.9-2.6%. Since then the prevalence of diabetes has doubled and the organisation of diabetes care has undergone major changes. Up-to-date data that quantify the occurrence of diabetic foot ulcers are required and could serve as baseline measures for future studies.

METHODS

Individuals with diabetes (n = 81,793) were identified from the NIVEL (Netherlands institute for health services research) Primary Care Database, which contains data for standardised routine care and is representative of the Dutch population. The annual incidence rates of ulcers and other foot abnormalities were calculated using data collected between 2010 and 2013. To account for inaccuracies, incidence rates were calculated using: (1) only individuals with a documented foot examination; (2) all individuals; and (3) individuals with explicit documentation of present/absent foot ulceration.

RESULTS

There were 412 individuals with documented ulceration during the registration period (0.50%). The annual incidence rate of foot ulcers was 0.34% (range 0.22-1.08%). Of those individuals with a documented foot examination, 14.6% had absent pedal pulsations, 17.3% had neuropathy and 10.1% had callus/pressure marks.

CONCLUSIONS/INTERPRETATION

The annual incidence rate of foot ulcers in the current study was lower than previously reported. This observation could reflect the efficacy of screening practices and an increased awareness among professionals and patients. Nevertheless, approximately one in every five diabetic individuals had at least one identifiable risk factor on foot examination. This signifies the importance of preventive screening.

Efficacy and safety of acellular dermal matrix in diabetic foot ulcer treatment: A systematic review and meta-analysis

BACKGROUND

Diabetic foot ulcer(DFU) is a chronic, refractory disease in need of multidisciplinary endeavour, miscellaneous strategies have been adopted to address this annoying issue, including acellular dermal matrix(ADM)/negative pressure wound therapy/standard of care (SOC) etc. However, consensus has not been reached. As a promising procedure, the efficacy and safety of ADM remains controversial. We therefore performed a meta-analysis of randomized controlled trials (RCTs) to compare the efficacy and safety of acellular dermal matrix to standard of care in DFU.

METHODS

Databases, including Pubmed, Medline, Embase and Cochrane library were searched to identify RCTs comparing ADM to SOC in DFU patients. The outcomes mainly included complete wound healing, mean time to heal and adverse events.

RESULTS

A total of 632 DFU patients from 6 RCTs were subjected to meta-analysis. The results showed that compared with the merely SOC, the complete healing rate in ADM group was higher both at 12 weeks [risk ratio (RR) 2.31, 95% confidence interval (CI) 1.42 to 3.76] and 16 weeks [RR 1.57, 95% CI 1.28 to 1.93]. The mean time to complete wound healing was shorter in ADM group [MD = -2.98, 95% CI: -5.15 to -0.82]. The occurrence of adverse event in both groups showed no significant difference [RR 0.98, 95%CI 0.58 to 1.67].

CONCLUSION

Compared with standard of care, acellular dermal matrix may accelerate the healing velocity of uninfected, non-ischemic, full-thickness diabetic foot ulcer. Acellular dermal matrix showed superiority compared with standard of care alone, while generating no more complications.

Partial calcanectomy and Ilizarov external fixation may reduce amputation need in severe diabetic calcaneal ulcers

Objective: The treatment of diabetic hindfoot ulcers is a challenging problem. In addition to serial surgical debridements, hyperbaric oxygen therapy and local wound care play important roles in the surgeon’s armamentarium, for both superficial infection and gangrene of the soft tissue, often complicated by osteomyelitis of the calcaneus. The purpose of this study was to evaluate the results of an aggressive approach from diagnosis to treatment of calcaneal osteomyelitis in foot-threatening diabetic calcaneal ulcers.

Methods: The study included 23 patients with diabetic hindfoot ulcers who were treated with radical excision of the necrotic tissue and application of circular external fixation. The treatment protocol was a combination of magnetic resonance imaging (MRI)-guided debridement of the necrotic tissues and application of an Ilizarov external fixator in plantarflexion to decrease the soft-tissue defect. Primary outcome measures were total cure of infection and obvious healing of the osteomyelitis at 12 weeks determined by MRI, and clinical cure through objective assessment of the appearance of the wound.

Results: The wounds healed in 18 of the 23 patients (78%), partial recovery occurred and subsequent flap operation was performed in three patients (13%), and below-the-knee amputation was performed in two patients (9%).

Conclusions: This surgical protocol is effective in ameliorating diabetic hindfoot ulcers with concomitant calcaneal osteomyelitis, and satisfactorily reduces the need for amputation.

Efficacy of a collagen-based dressing in an animal model of delayed wound healing

OBJECTIVE

The aim of this study was to evaluate in vitro and in vivo the efficacy of GBT013, a collagen-based dressing, for the treatment of chronic wounds, in a db/db mouse model of diabetes.

METHOD

Macroscopic and histologic analyses of db/db mice wound healing with GBT013 or saline gauze were assessed. The mRNA expression and the proliferation of dermal fibroblast were investigated. Matrix metalloproteinases (MMP)-2 and MMP-9 activities were quantified.

RESULTS

In db/db mice, GBT013 improves wound epithelialisation when compared with saline gauze. Histological analysis of scar tissue also shows an enhancement of remodelling associated with no sign of acute inflammation. In addition, GBT013 significantly decreases interleukin (IL)-6 and IL-8, significantly increases tissue inhibitors of metalloproteinases (TIMP)-1 and TIMP-2 fibroblast mRNA expression and significantly reduces in vitro MMP-2 and MMP-9 enzymatic activities. Moreover, GBT013 allows cell growth inside the matrix and stimulates proliferation of human dermal fibroblast.

CONCLUSION

By contributing to restore MMPs/TIMPs balance, GBT013 may function in all key stages of wound healing, such as inflammation, proliferation and tissue remodelling, and ultimately may provide a favourable environment for skin repair.

DECLARATION OF INTEREST

This work was supported by Genbiotech, the R&D subsidiary of Laboratoires Genévrier, a pharmaceutical company.

Clinical effectiveness of hemoglobin spray (Granulox®) as adjunctive therapy in the treatment of chronic diabetic foot ulcers

INTRODUCTION

Hemoglobin spray (Granulox®) comprises purified hemoglobin and is a novel approach for increasing oxygen availability in the wound bed in diabetic foot ulcer patients. Its mode of action is to bind oxygen from the atmosphere and diffuse it into the wound bed to accelerate wound healing in slow-healing wounds.

PATIENTS AND METHODS

Wound healing outcomes, that is, wound size, pain, percentage of slough, and exudate levels, were compared retrospectively to a similar cohort of patients treated over the same period the previous year. The same inclusion and exclusion criteria applied to both groups.

RESULTS

All 20 (100%) hemoglobin spray-treated patients and 15 (75%) control patients experienced some wound healing by week 4, with 5 (25%) and 1 (5%), respectively, achieving complete wound closure. At week 4, mean wound size reduction was 63% in the hemoglobin spray group versus 26% for controls, increasing to 95% reduction at week 28 in the hemoglobin spray group versus 63% for controls (p<0.05 at all timepoints). Hemoglobin spray was associated with substantially lower pain scores using a 10-cm visual analogue scale, with 19/19 patients (100%) being pain-free from week 12 onwards, compared to 6/18 patients (33%) in the control group. At week 28, 2/18 patients (11%) in the control group still had pain. Both groups had similar baseline slough levels, but hemoglobin spray-treated wounds had slough completely eliminated after 4 weeks versus 10% mean reduction in the control group (p<0.001). Hemoglobin spray was associated with markedly reduced exudate levels; within 4 weeks, no patients had high exudate levels in the hemoglobin spray group versus 5 in the control group.

CONCLUSION

Standard wound care plus hemoglobin spray results in improvements in wound closure, wound size reduction, pain, slough, and exudate levels compared to control patients for chronic diabetic foot ulcer treatment.

Evaluation of wound healing in diabetic foot ulcer using platelet-rich plasma gel: A single-arm clinical trial

The aim of the present study was to evaluate the effectiveness of using autologous platelet-rich plasma (PRP) gel for treatment of diabetic foot ulcer (DFU) during the first 4 weeks of the treatment. In this longitudinal and single-arm trial, 100 patients were randomly selected after meeting certain inclusion and exclusion criteria; of these 100 patients, 70 (70%) were enrolled in the trial. After the primary care actions such as wound debridement, the area of each wound was calculated and recorded. The PRP therapy (2mL/cm² of ulcers) was performed weekly until the healing time for each patient. We used one sample T-test for healing wounds and Bootstrap resampling approach for reporting confidence interval with 1000 Bootstrap samples. The p-value<0.05 were considered statistically significant. The mean (SD) of DFU duration was 19.71 weeks (4.94) for units sampling. The ratio of subjects who withdrew from the study was calculated to be 2 (2.8%). Average area of 71 ulcers in the mentioned number of cases was calculated to be 6.11cm² (SD: 4.37). Also, the mean, median (SD) of healing time was 8.7, 8 weeks (SD: 3.93) except for 2 mentioned cases. According to one sample T-test, wound area (cm²), on average, significantly decreased to 51.9% (CI: 46.7-57.1) through the first four weeks of therapy. Furthermore, significant correlation (0.22) was not found between area of ulcers and healing duration (p-value>0.5). According to the results, PRP could be considered as a candidate treatment for non-healing DFUs as it may prevent future complications such as amputation or death in this pathological phenomenon.

Development of a Novel Collagen Wound Model To Simulate the Activity and Distribution of Antimicrobials in Soft Tissue during Diabetic Foot Infection

Diabetes has major implications for public health, with diabetic foot ulcers (DFUs) being responsible for significant morbidity and mortality. A key factor in the development of nonhealing ulcers is infection, which often leads to the development of biofilm, gangrene, and amputation. A novel approach to treating DFUs is the local release of antibiotics from calcium sulfate beads. We have developed a novel model system to study and compare the release and efficacy of antibiotics released locally, using collagen as a substrate for biofilm growth and incorporating serum to mimic the biochemical complexity of the wound environment. We found that our soft-tissue model supports the growth of a robust Pseudomonas aeruginosa biofilm, and that this was completely eradicated by the introduction of calcium sulfate beads loaded with tobramycin or gentamicin. The model also enabled us to measure the concentration of these antibiotics at different distances from the beads and in simulated wound fluid bathing the collagen matrix. We additionally found that a multidrug-resistant Staphylococcus aureus biofilm, nonsusceptible to antibiotics, nonetheless showed an almost 1-log drop in viable counts when exposed to calcium sulfate beads combined with antibiotics. Together, these data suggest that locally applied antibiotics combined with calcium sulfate provide surprising efficacy in diabetic foot infections and offer an effective alternative approach to infection management. Our study additionally establishes our new system as a biochemically and histologically relevant model that may be used to study the effectiveness of a range of therapies locally or systemically for infected DFUs.