Incidence of lower-limb amputation in the diabetic and nondiabetic general population: a 10-year population-based cohort study of initial unilateral and contralateral amputations and reamputations

Amputation Risk in Type II Diabetes Mellitus Patients Treated with SGLT-2 Inhibitors: A Systematic Literature Review of Randomized Clinical Trials

BACKGROUND

SGLT-2 inhibitors, prescribed for type 2 diabetes, have a heightened risk of amputation. The FDA issued a warning in May 2017, leading to the inclusion of a cautionary label. Vigilance is essential for patients and healthcare providers to promptly identify and address potential limb complications associated with the use of SGLT-2 inhibitors.

METHOD

A comprehensive search of electronic databases was conducted, covering the period from inception to May 2024. This systematic literature review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The quality of the included studies was assessed using the Cochrane risk of bias (ROB) tool. Inclusion and exclusion criteria were predefined, and data extraction was performed to summarize the findings.

RESULT

A total of 12 randomized control trial (RCT) studies were included in the present systematic review. 37,657 (54.89%) participants were randomly assigned to receive the different interventions of SGLT-2 inhibitor, whereas 30,959 (45.11%) received a placebo. Overall, 618 events were reported in the treatment group, whereas 396 events were reported in the placebo group.

CONCLUSION

In conclusion, patients treated with SGLT-2 inhibitors did not have any significant difference in amputation occurrences compared to placebo across various studies. However, canagliflozin usage has led to higher amputation events in certain trials.

The Physiatrist's Approach to Limb Loss: Pre-amputation Through Lifelong Care

Limb-loss is a significant medical event with lifelong consequences, impacting various aspects of a patient's well-being. Care for these often-complex patients involves providers from many different specialties working toward a set of patient-centered goals. This article aims to highlight the important role of physiatrists in directing the interdisciplinary care for these patients. Through evidence-based concepts, the authors aim to lay a roadmap for comprehensive, longitudinal management of these patients from pre-amputation assessment through lifelong care.

Perioperative Risk Factors for Early Major Amputation Following First-Time Diabetic Forefoot Amputation

BACKGROUND

Despite a meticulous multidisciplinary team approach, limb salvage remains uncertain even after the initial forefoot amputation in patients with end-stage diabetes. Which of many factors strongly influence the early failure of the limb salvage strategy remains unknown. This study aimed to analyze perioperative independent risk factors for major amputation within 1 year following first-time diabetic forefoot amputation.

METHODS

Perioperative variables of 808 diabetic forefoot amputations performed in a tertiary referral center specialized for organ transplantation and end-stage diabetes were analyzed. Major amputations were performed in 104 patients (12.9%) throughout follow-up, and 77 (74%) of 104 patients had their major amputation within 1 year. Cox proportional hazards were examined to assess the risk factors for major amputation performed within 1 year.

RESULTS

In univariate analysis, 18 possible risk factors significantly differed between patients with and without early major amputation. In stepwise multivariable analysis, chronic renal failure (CRF), peritoneal dialysis, and bilateral initial amputation were strong risk factors for early major amputation, with hazard ratios of 2.973 (95% CI 1.805-4.896, P < .0001), 2.558 (95% CI 1.113-5.881, P = .027), and 2.515 (95% CI 1.318-4.798, P = .005), respectively.

CONCLUSION

Regardless of kidney transplantation (KT) status, CRF strongly predicts >20% chance of major amputation within 1 year after the first diabetic forefoot amputation.

Above-ankle Reamputation and Mortality following Transmetatarsal Amputation in Diabetic and Nondiabetic Peripheral Artery Disease

The risk of above-ankle reamputation following a transmetatarsal amputation is around 30%. Patient selection may be crucial to achieve good outcomes, and to avoid futile operations and suffering. We are aware of no previous comparison between the two largest patient groups that undergo lower extremity amputations: patients with diabetes, and patients with non-diabetic peripheral artery disease. Patients with diabetes or nondiabetic peripheral artery disease who had undergone a transmetatarsal amputation from 2004 to 2018 at our institution were included. Patient characteristics and perioperative details were analyzed retrospectively. Subjects with diabetes were compared with subjects with nondiabetic peripheral artery disease regarding above-ankle reamputation, reamputation level, and mortality. Five-hundred-and-sixty transmetatarsal amputations in 513 subjects were included. The majority of transmetatarsal amputations (86%) occurred in diabetic subjects. Subjects with non-diabetic PAD had a higher risk of above-ankle reamputation (p = .008), and death (p < .001). At the time of data collection, only multiple-ray amputation (vs. single-ray) was an independent risk factor for above-ankle reamputation. Only age, medical comorbidity in general, and chronic heart failure were independent risk factors of death. To our knowledge, this study is the first to report marked differences in above-ankle reamputation rates and mortality following transmetatarsal amputation, comparing diabetics with non-diabetic patients with peripheral artery disease. However, the differences may be attributed to non-diabetics being older, having more medical comorbidities, and having more advanced foot ulcers at the time of transmetatarsal amputation. In patients exhibiting several of these risk factors, transmetatarsal amputation may be futile.

Exploring potential risk factors for lower limb amputation in people with diabetes-A national observational cohort study in Sweden

AIMS

Risk factors for lower limb amputation (LLA) in individuals with diabetes have been under-studied. We examined how 1/demographic and socioeconomic, 2/medical, and 3/lifestyle risk factors may be associated with LLA in people with newly diagnosed diabetes.

METHODS

Using the Swedish national diabetes register from 2007 to 2016, we identified all individuals ≥18 years with an incident diabetes diagnosis and no previous amputation. These individuals were followed from the date of diabetes diagnosis to amputation, emigration, death, or the end of the study in 2017 using data from the In-Patient Register and the Total Population Register. The cohort consisted of 66,569 individuals. Information about demographic, socioeconomic, medical, and lifestyle risk factors was ascertained around the time of the first recorded diabetes diagnosis, derived from the above-mentioned registers. Cox proportional hazard models were used to obtain hazard ratios (HR) with 95% confidence intervals (CI).

RESULTS

During the median follow-up time of 4 years, there were 133 individuals with LLA. The model adjusting for all variables showed a higher risk for LLA with higher age, HR 1.08 (95% CI 1.05-1.10), male sex, HR 1.57 (1.06-2.34), being divorced, HR 1.67 (1.07-2.60), smokers HR 1.99 (1.28-3.09), insulin treated persons HR 2.03 (1.10-3.74), people with low physical activity (PA) HR 2.05 (1.10-3.74), and people with an increased foot risk at baseline HR > 4.12. People with obesity had lower risk, HR 0.46 (0.29-0.75).

CONCLUSIONS

This study found a higher risk for LLA among people with higher age, male sex, who were divorced, had a higher foot risk group, were on insulin treatment, had lower PA levels, and were smokers. No significant association was found between risk for LLA and education level, country of origin, type of diabetes, blood glucose level, hypertension, hyperlipidemia, creatinine level, or glomerular filtration rate. Obesity was associated with lower risk for LLA. Identified variables may have important roles in LLA risk among people with diabetes.

Prediction model for lower limb amputation in hospitalized diabetic foot patients using classification and regression trees

BACKGROUND

The decision to perform amputation of a limb in a patient with diabetic foot ulcer (DFU) is not an easy task. Prediction models aim to help the surgeon in decision making scenarios. Currently there are no prediction model to determine lower limb amputation during the first 30 days of hospitalization for patients with DFU.

METHODS

Classification And Regression Tree analysis was applied on data from a retrospective cohort of patients hospitalized for the management of diabetic foot ulcer, using an existing database from two Orthopaedics and Traumatology departments. The secondary analysis identified independent variables that can predict lower limb amputation (mayor or minor) during the first 30 days of hospitalization.

RESULTS

Of the 573 patients in the database, 290 feet underwent a lower limb amputation during the first 30 days of hospitalization. Six different models were developed using a loss matrix to evaluate the error of not detecting false negatives. The selected tree produced 13 terminal nodes and after the pruning process, only one division remained in the optimal tree (Sensitivity: 69%, Specificity: 75%, Area Under the Curve: 0.76, Complexity Parameter: 0.01, Error: 0.85). Among the studied variables, the Wagner classification with a cut-off grade of 3 exceeded others in its predicting capacity.

CONCLUSIONS

Wagner classification was the variable with the best capacity for predicting amputation within 30 days. Infectious state and vascular occlusion described indirectly by this classification reflects the importance of taking quick decisions in those patients with a higher compromise of these two conditions. Finally, an external validation of the model is still required.

LEVEL OF EVIDENCE

III.

Risk factors for 30-day hospital readmission in patients with diabetic foot

INTRODUCTION

Diabetic foot (DF) is part of the natural history of diabetes mellitus, ulceration being a severe complication with a prevalence of approximately 6.3 %, which confers a significant economic burden. Hospital readmission in the first thirty (30) days is considered a measure of quality of healthcare and it's been identified that the most preventable causes are the ones that occur in this period. This study seeks to identify the risk factors associated with readmission of patients with DF.

METHODS

A case-control study was done by performing a secondary analysis of a database. Descriptive statistics were used for all variables of interest, bivariate analysis to identify statistically significant variables, and a logistic regression model for multivariate analysis.

RESULTS

575 cases were analyzed (113 cases, 462 controls). A 20 % incidence rate of 30-day readmission was identified. Statistically significant differences were found in relation to the institution of attention (Hospital Universitario de la Samaritana: OR 1.9, p value < 0.01, 95 % CI 1.2-3.0; Hospital Universitario San Ignacio: OR 0.5, p value < 0.01, 95 % CI 0.3-0.8) and the reasons for readmission before 30 days, especially due to surgical site infection (SSI) (OR 7.1, p value < 0.01, 95 % CI 4.1-12.4), sepsis (OR 8.4, p value 0.02, 95 % CI 1.2-94.0), dehiscence in amputation stump (OR 16.4, p value < 0.01, 95 % CI 4.2-93.1) and decompensation of other pathologies (OR 3.5, p value < 0.01, 95 % CI 2.1-5.7).

CONCLUSION

The hospital readmission rate before 30 days for our population compares to current literature. Our results were consistent with exacerbation of chronic pathologies, but other relevant variables not mentioned in other studies were the hospital in which patients were taken care of, the presence of SSI, sepsis, and dehiscence of the amputation stump. We consider thoughtful and close screening of patients at risk in an outpatient setting might identify possible readmissions.

Retention of Improved Plantar Sensation in Patients with Type II Diabetes Mellitus and Sensory Peripheral Neuropathy after One Month of Vibrating Insole Therapy: A Pilot Study

Sensory peripheral neuropathy is a common complication of diabetes mellitus and the biggest risk factor for diabetic foot ulcers. There is currently no available treatment that can reverse sensory loss in the diabetic population. The application of mechanical noise has been shown to improve vibration perception threshold or plantar sensation (through stochastic resonance) in the short term, but the therapeutic use, and longer-term effects have not been explored. In this study, vibrating insoles were therapeutically used by 22 participants, for 30 min per day, on a daily basis, for a month by persons with diabetic sensory peripheral neuropathy. The therapeutic application of vibrating insoles in this cohort significantly improved VPT by an average of 8.5 V (p = 0.001) post-intervention and 8.2 V (p < 0.001) post-washout. This statistically and clinically relevant improvement can play a role in protection against diabetic foot ulcers and the delay of subsequent lower-extremity amputation.

Comorbidity and risk factors of subsequent lower extremity amputation in patients diagnosed with diabetes in Saskatchewan, Canada

OBJECTIVE

Subsequent limb amputation (SLA) may be necessary due to disease progression, infection, or to aid prosthesis fit. SLA in Saskatchewan has increased 3.2% from 2006 to 2019 with minor SLA increasing 9.6% during that period. Diabetes affects a large proportion of patients who require SLA; however, the impact of additional comorbidities is not clear.

METHODS

First-episode subsequent lower extremity limb amputation (SLEA) cases with the presence/absence of diabetes, other comorbidities, and demographic characteristics from 2006-2019 were retrieved from Saskatchewan's Discharge Abstract Database. Logistic regression was performed to examine the magnitude of the odds of SLEA.

RESULTS

Among the 956 first-episode SLEA patients investigated, 78.8% were diagnosed with diabetes. Of these, 76.1% were male and 83.0% were aged 50 + years. Three comorbidities: renal failure (AOR = 1.9, 95% Cl 1.1 - 3.0), hypertension (AOR = 3.0, 95% Cl 2.0 - 4.5), and congestive heart failure (AOR = 2.0, 95% CI 1.2 - 3.2), conferred the highest odds of SLEA. The odds of SLEA is greatest for those aged 50-69 years, males, Registered Indians, and associated with a prolonged hospital stay.

DISCUSSION

These data are important as they may help medical providers identify patients at the highest risk of SLEA and target interventions to optimize outcomes.

Delivery of multipotent adult progenitor cells via a functionalized plasma polymerized surface accelerates healing of murine diabetic wounds

Introduction: Stem cell therapies have been investigated as potential treatment modalities for chronic wounds however there has been limited success to date. Multipotent Adult Progenitor Cells (MAPCs©) have been identified as having potential as an allogenic stem cell product due to their high population doubling number and their characteristic dampening of T-cell proliferation. This helps to prevent autoimmunity and graft/cell rejection. Methods: We have developed a dressing, consisting of medical grade silicone coated with a heptylamine plasma polymer, which supports the growth and transfer of MAPCs to skin. To determine if the dressing can deliver functional stem cells into diabetic wounds, they were loaded with MAPCs and then placed over excisional wounds in both normal and diabetic mice. Results and discussion: Accelerated healing was observed in both the normal and diabetic wounds with wound gape being significantly smaller at day 3 when compared to controls. Wound analysis showed that treatment with the MAPC dressings dampened the inflammatory response with reduced numbers of neutrophils and macrophages observed. Additionally, an increase in pro-angiogenic VEGF and CD31 positive endothelial cells was observed indicating improved new blood vessel formation. The MAPC dressings had no effect on fibrosis with collagen I and III being equally affected in both control and treated wounds. Overall, the functionalized MAPC dressings improve healing responses particularly in diabetic mice with impaired healing responses and therefore, show potential for development as an advanced therapeutic approach for the treatment of chronic diabetic wounds.

The Influence of Diabetes Mellitus on Mortality of Patients After Lower Extremity Amputation: A Systematic Review and Meta-analysis

OBJECTIVE

The influence of diabetes mellitus (DM) on mortality following lower extremity amputation (LEA) remains controversial. This systematic review and meta-analysis aimed to determine the influence of DM on long-term mortality (LTM) and short-term mortality (STM) after amputation.

MATERIALS AND METHODS

The Medline, the Cochrane library, and Embase databases were searched. The primary and secondary outcomes were LTM and STM following amputation. One-year and 30-day all-cause mortality after amputation were considered as LTM and STM, respectively. A random-effects model was utilized to pool results. To evaluate the stability of results, subgroup analyses and sensitivity analyses were conducted.

RESULTS

Twenty-three cohort studies with a total of 58,219 patients were included, among which 31,750 (54.5%) patients had DM. The mean score of included studies evaluated by Newcastle-Ottawa Scale was 7.65, indicating moderate to high quality. The pooled results showed no significant difference in 1-year LTM (risk ratio [RR], 0.96; 95% CI 0.86-1.07) after amputation. However, 3-year (RR, 1.22; 95% CI 1.01-1.47) and 5-year (RR, 1.18; 95% CI 1.07-1.31) LTMs of DM patients were obviously higher than that of NDM (non-diabetes mellitus) patients. The STM of the DM group was significantly lower than the NDM group (RR, 0.80; 95% CI 0.64-0.98).

CONCLUSIONS

The current study revealed that DM patients had an obvious lower STM following LEA, but the risk of DM on LTM after amputation was gradually increased with time. More attention should be paid to the long-term survival of DM patients after LEA.

Risk factors for reamputation in patients with diabetic foot: A case-control study

BACKGROUND

Reamputation as a complication of diabetic foot ulcers presents a high economic burden and represents a therapeutic failure. It is paramount to identify as early as possible patients in whom a minor amputation may not be the best option. The purpose of this investigation was to do a case-controlled study to determine risk factors associated with re-amputation in patients with DFU (diabetic foot ulcers) at two University Hospitals.

METHODS

Multicentric, observational, retrospective, case-control study from clinical records of 2 university hospitals. Our study included 420 patients, with 171 cases (re-amputations), and 249 controls. We performed a multivariate logistic regression analysis and time-to-event survival analysis to identify re-amputation risk factors.

RESULTS

Statistically significant risk factors were artery history of tobacco use (p = 0.001); male sex (p = 0.048); arterial occlusion in Doppler ultrasound (p = 0.001); percentage of stenosis in arterial ultrasound >50 % (p = 0.053); requirement of vascular intervention (p = 0.01); and microvascular involvement in photoplethysmography (p = 0.033). The most parsimonious regression model suggests that history of tobacco use, male sex, arterial occlusion in ultrasound, and percentage of stenosis in arterial ultrasound >50 % remained statistically significant. The survival analysis identified earlier amputations in patients with larger occlusion in arterial ultrasound, high leukocyte count, and elevated ESR.

CONCLUSION

Direct and surrogate outcomes in patients with diabetic foot ulcers identify vascular involvement as an important risk factor for reamputation.

LEVEL OF EVIDENCE

III.

High-normal serum bilirubin decreased the risk of lower limb atherosclerosis in type 2 diabetes: a real-world study

BACKGROUND

Bilirubin has been found to protect against overt atherosclerotic diseases, but to date, few studies have investigated the effects of bilirubin especially within the normal range on lower limb atherosclerosis. Therefore, we aimed to assess the associations of bilirubin within normal limits including total bilirubin (TB), conjugated bilirubin (CB) and unconjugated bilirubin (UCB) with lower limb atherosclerosis in Chinese patients with type 2 diabetes mellitus (T2DM).

METHODS

7284 T2DM patients with normal levels of serum bilirubin were included in this cross-sectional, real-world study. Patients were divided into quintiles by TB levels (< 8.7, 8.7-10.19, 10.20-11.99, 12-13.99, > 13.99 µmol/L). Lower limb ultrasonography was conducted to detect lower limb plaque and stenosis. The association between serum bilirubin and lower limb atherosclerosis was explored by multiple logistic regression.

RESULTS

A remarkable decrease in the prevalence of lower limb plaque (77.5, 75.3, 70.7, 71.7 and 67.9%) and stenosis (21.1, 17.2, 13.3, 13.0 and 12.0%) was observed across the TB quintiles. Multivariable regression analysis showed that serum TB levels were negatively correlated with higher risks of lower limb plaque and stenosis, both as a continuous variable [OR (95%CI): 0.870 (0.784-0.964), p = 0.008 for plaque; and 0.835 (0.737-0.946), p = 0.005 for stenosis] and as categorized in quintiles (p = 0.015 and 0.016 for plaque and stenosis). Interestingly, serum CB levels were only negatively correlated with lower limb stenosis [OR (95%CI): 0.767 (0.685-0.858), p < 0.001], whereas serum UCB levels were only negatively associated with lower limb plaque [ OR (95%CI): 0.864 (0.784-0.952), p = 0.003] after a fully-adjusted analysis. Furthermore, serum CRP was significantly decreased across the TB quintiles and negatively associated with serum TB (r = -0.107, p < 0.001), CB (r = -0.054, p < 0.001), and UCB (r = -0.103, p < 0.001).

CONCLUSIONS

High-normal serum bilirubin levels were independently and significantly related to reduced risks of lower limb atherosclerosis in T2DM patients. Furthermore, serum bilirubin levels including TB, CB and UCB were inversely correlated with CRP. These results suggested that higher-normal serum bilirubin may exhibit an anti-inflammatory and protective effect against lower limb atherosclerotic progression in T2DM subjects.

Epidemiology and Outcome of Nontraumatic Lower Limb Amputations

Background

In order to create a solid evidence base for the development of improved management methods, this study was performed to describe the epidemiology and outcome of nontraumatic lower limb amputations (LLAs).

Methods

This descriptive case series was conducted over a period of 4 years. It included all patients of both sexes and all ages who underwent LLAs for nontraumatic indications.

Results

There were a total of 217 patients with 136 (62.67%) men and 81(37.32%) women. The age range was 7 to 71 years, with a mean of 54.25 ± 11.49 years. The most common indication for amputation (41.47%) was diabetic foot gangrene. The most common level of amputation (48.29%) was below knee amputation.

Conclusion

Patients with diabetic foot gangrene, malignant tumors, and chronic neuropathic ulcers with osteomyelitis constituted the bulk of the amputees. Diabetes mellitus, obesity, and hypertension were the commonest comorbidities identified among them. Public awareness and education would ensure prompt and early health seeking at the appropriate time and help to prevent the need for major amputations in many instances. The amputees' improved reintegration into society and ability to become contributing members of society would be ensured by the provision of vigorous rehabilitation.

Vascular Endothelial Growth Factor Single Nucleotide Polymorphism +405 G/C (rs2010963) is associated with Levels, Infection Severity, and Amputation among South Indian Diabetic Foot Ulcer Patients

Background

The regulation of vascular endothelial growth factor (VEGF) by genetic factors in T2DM and DFU still requires thorough investigation. Hence, the present study aimed to investigate the association of VEGF +405 G/C in DFU subjects and correlate it with its circulatory levels, infection severity, and amputation rate.

Materials and Methods

This study registered a total of 754 participants of which group I: healthy controls (n = 297), group II: T2DM subjects (n = 242), and group III: DFU subjects (n = 215). Genotyping and levels of rs2010963 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and ELISA, respectively.

Results

Results of the current study showed a clear decline in circulatory VEGF-A levels in DFU subjects. VEGF-A was decreased in DFU subjects with the mutant "CC" genotype. The mutant "CC" of VEGF +405G/C was also found to be more susceptible to ulcer grade (III and IV) and major amputations.

Conclusion

VEGF +405G/C SNP is associated with levels, infection severity, and amputation amongst South Indian DFU patients.

Effects of Implementing a Self-Care Program for Adults With Lower Limb Prostheses

An artificial replacement for a lost limb or portion of a limb, known as a prosthesis, is a tool that can assist a person to regain their independence. The aim of this project was to evaluate the effect of a self-care program for adults with lower limb prostheses. We used a quasi-experimental research design. We conducted our study at the Physical Medicine and Rehabilitation and Rheumatology Center affiliated with the Armed Forces, located in the Al-Geza Governorate of Egypt using a purposeful sample of 81 adults with lower limb prostheses. We used two tools for data collection: a structured interviewing questionnaire and the Trinity Amputation and Prosthesis Experience Scales (TAPES). The mean age of adults with lower limb prosthesis in our study was 38.91 years (10.53). A total of 64.2% of the study participants (n = 51) were men. We found that before the self-care program, 22.2% of the participants (n = 18) had a satisfactory level of knowledge about self-care, which increased to 88.9% (n = 72) after the program. Before the self-care program, the number of participants with adequate practice levels was 13.6% (n = 11), which increased to 100.0% (n = 81) after the program. We concluded that implementing the self-care program provided a significant improvement in the attendee's total satisfactory knowledge (χ2[79,81] = 72.90, p < .000) and adequate practice levels (p < .001).

Trends in the incidence rates of lower limb amputation due to nondiabetic peripheral artery disease in a large industrial city in Western Siberia, Russia: A review from 1996 to 2019

BACKGROUND

lower limb amputation (LLA) is a growing problem in the population with and without diabetes mellitus. Monitoring the incidence rates of LLA is important for health care planning and has implications for the future problems of medical and social care.

OBJECTIVE

This study aimed to determine the trends in incidence rates of LLA due to nondiabetic peripheral artery disease in Novokuznetsk, Western Siberia, Russia.

STUDY DESIGN

An observational study.

METHODS

Data on all transtibial and transfemoral amputations performed in inpatient facilities in Novokuznetsk from 1996 to 2019 were derived from the regional Register of patients with limb amputations. The rates were calculated per 100,000 population.

RESULTS

A total of 2448 persons with amputations due to nondiabetic peripheral artery disease were included in this study (3191 amputations). The overall incidence rate of LLA in Novokuznetsk increased from 14.6 in 1996 to 30.4 in 2019. The proportion of persons older than 60 years increased from 15.5% in 1996 to 20.3% in 2019.

CONCLUSION

The expected aging of the population and increasing incidence of LLA are relevant issues in Russia. These findings can contribute to improving healthcare services and the development of prevention programs to reverse the alarming trend.

New Horizons of Macrophage Immunomodulation in the Healing of Diabetic Foot Ulcers

Diabetic foot ulcers (DFUs) are one of the most costly and troublesome complications of diabetes mellitus. The wound chronicity of DFUs remains the main challenge in the current and future treatment of this condition. Persistent inflammation results in chronic wounds characterized by dysregulation of immune cells, such as M1 macrophages, and impairs the polarization of M2 macrophages and the subsequent healing process of DFUs. The interactive regulation of M1 and M2 macrophages during DFU healing is critical and seems manageable. This review details how cytokines and signalling pathways are co-ordinately regulated to control the functions of M1 and M2 macrophages in normal wound repair. DFUs are defective in the M1-to-M2 transition, which halts the whole wound-healing machinery. Many pre-clinical and clinical innovative approaches, including the application of topical insulin, CCL chemokines, micro RNAs, stem cells, stem-cell-derived exosomes, skin substitutes, antioxidants, and the most recent Phase III-approved ON101 topical cream, have been shown to modulate the activity of M1 and M2 macrophages in DFUs. ON101, the newest clinically approved product in this setting, is designed specifically to down-regulate M1 macrophages and further modulate the wound microenvironment to favour M2 emergence and expansion. Finally, the recent evolution of macrophage modulation therapies and techniques will improve the effectiveness of the treatment of diverse DFUs.

Impact of photobiomodulation on macrophages and their polarization during diabetic wound healing: a systematic review

This review aims to providing essential information and the current knowledge about the potential role of macrophages, especially their M2 subtypes in different diabetic wounds both in clinical and pre-clinical models under the influence of photobiomodulation (PBM). The long-term goal is to advance the macrophage-based therapies to accelerate healing of diabetic foot ulcers. We reviewed all databases provided by PubMed, Google Scholar, Scopus, Web of Science, and Cochrane precisely from their dates of inception to 25/10/2021. The keywords of Diabetes mellitus diseases, wound healing, macrophage, and photobiomodulation or low-level laser therapy were used in this systematic review.A total of 438 articles were initially identified in pubmed.ncbi.nlm.nih.gov (15 articles), Google scholar (398 articles), Scopus (18 articles), and Web of Science (7 articles). Four hundred sixteen articles that remained after duplicate studies (22 articles) were excluded. After screening abstracts and full texts, 14 articles were included in our analysis. Among them, 4 articles were about the effect of PBM on macrophages in type 2 diabetes and also found 10 articles about the impact of PBM on macrophages in type 1 diabetes. The obtained data from most of the reviewed studies affirmed that the PBM alone or combined with other agents (e.g., stem cells) could moderate the inflammatory response and accelerate the wound healing process in pre-clinical diabetic wound models. However, only very few studies conducted the detailed functions of polarized macrophages and M2 subtypes in wound healing of diabetic models under the influence of PBM. Further pre-clinical and clinical investigations are still needed to investigate the role of M2 macrophages, especially its M2c subtype, in the healing processes of diabetic foot ulcers in clinical and preclinical settings.

Combination stem cell therapy using dental pulp stem cells and human umbilical vein endothelial cells for critical hindlimb ischemia

Narrowing of arteries supplying blood to the limbs provokes critical hindlimb ischemia (CLI). Although CLI results in irreversible sequelae, such as amputation, few therapeutic options induce the formation of new functional blood vessels. Based on the proangiogenic potentials of stem cells, in this study, it was examined whether a combination of dental pulp stem cells (DPSCs) and human umbilical vein endothelial cells (HUVECs) could result in enhanced therapeutic effects of stem cells for CLI compared with those of DPSCs or HUVECs alone. The DPSCs+ HUVECs combination therapy resulted in significantly higher blood flow and lower ischemia damage than DPSCs or HUVECs alone. The improved therapeutic effects in the DPSCs+ HUVECs group were accompanied by a significantly higher number of microvessels in the ischemic tissue than in the other groups. In vitro proliferation and tube formation assay showed that VEGF in the conditioned media of DPSCs induced proliferation and vessel-like tube formation of HUVECs. Altogether, our results demonstrated that the combination of DPSCs and HUVECs had significantly better therapeutic effects on CLI via VEGF-mediated crosstalk. This combinational strategy could be used to develop novel clinical protocols for CLI proangiogenic regenerative treatments.

Predicting Amputation in Patients With Diabetic Foot Ulcers: A Systematic Review

Foot ulcers are a leading cause of morbidity in diabetics. One of the known complications of diabetic foot ulcers is lower limb amputation which makes it a major socioeconomic problem. Currently, there's a lack of knowledge on the predictors of amputations in diabetics with foot ulcers. We performed a systematic review of studies that identified risk factors of amputation in patients with diabetic foot ulcers. This systematic review aims to identify the predictors of amputation in order to optimize the management strategy and care plan. Medline database was searched and inclusion criteria were implemented for the selection of studies. The risk factors extracted were part of four categories: (i) history and physical examination, (ii) ulcer characteristics, (iii) lab results, and (iv) co-morbidities. The data extracted were in the form of odds ratios, 95% confidence intervals, and predictive values. The mean values with standard deviations of the included risk factors were recorded, and the incidence of risk factors among the amputation groups was identified or calculated when the data were sufficient. Seven articles were selected reporting on 3481 patients. This review identified peripheral arterial disease, neuropathy, high Wagner's grade, osteomyelitis, postprandial glucose level, white cell count, c-reactive protein, erythrocyte sedimentation rate, low hemoglobin, and albumin as the most significant predictors of amputation.

Combination stem cell therapy using dental pulp stem cells and human umbilical vein endothelial cells for critical hindlimb ischemia

Narrowing of arteries supplying blood to the limbs provokes critical hindlimb ischemia (CLI). Although CLI results in irreversible sequelae, such as amputation, few therapeutic options induce the formation of new functional blood vessels. Based on the proangiogenic potentials of stem cells, in this study, it was examined whether a combination of dental pulp stem cells (DPSCs) and human umbilical vein endothelial cells (HUVECs) could result in enhanced therapeutic effects of stem cells for CLI compared with those of DPSCs or HUVECs alone. The DPSCs+ HUVECs combination therapy resulted in significantly higher blood flow and lower ischemia damage than DPSCs or HUVECs alone. The improved therapeutic effects in the DPSCs+ HUVECs group were accompanied by a significantly higher number of microvessels in the ischemic tissue than in the other groups. In vitro proliferation and tube formation assay showed that VEGF in the conditioned media of DPSCs induced proliferation and vessel-like tube formation of HUVECs. Altogether, our results demonstrated that the combination of DPSCs and HUVECs had significantly better therapeutic effects on CLI via VEGF-mediated crosstalk. This combinational strategy could be used to develop novel clinical protocols for CLI proangiogenic regenerative treatments. [BMB Reports 2022; 55(7): 336-341].

Air microfluidics-enabled soft robotic transtibial prosthesis socket liner toward dynamic management of residual limb contact pressure and volume fluctuation

Residual limb volume fluctuation and the resulting contact pressures are some of the key factors leading to skin ulcerations, suboptimal prosthetic functioning, pain, and diminishing quality of life of transtibial amputees. Self-management of socket fit is complicated by peripheral neuropathy, reducing the perception of pressure and pain in the residual limb. We introduce a novel proof-of-concept for a transtibial prosthetic socket liner with the potential to dynamically adjust the fit between the limb and socket. The core of the technology is a small air microfluidic chip (10 cm3 and 10 g) with 10 on-chip valves that enable sequential pressurizing of 10 actuators in custom sizes to match the pressures required by the residual limb's unique anatomy. The microfluidic chip largely reduced the number of electromechanical solenoid valves needed for sequential control of 10 actuators (2 instead of 10 valves), resulting in the reduction of the required power, size, mass, and cost of the control box toward an affordable and wearable prosthetic socket. Proof-of-concept testing demonstrated that the applied pressures can be varied in the desired sequence and to redistribute pressure. Future work will focus on integrating the system with biofidelic prosthetic sockets and residual limb models to investigate the ability to redistribute pressure away from pressure-sensitive regions (e.g., fibular head) to pressure tolerant areas. Overall, the dynamic prosthesis socket liner is very encouraging for creating a dynamic socket fit system that can be seamlessly integrated with existing socket fabrication methods for managing residual limb volume fluctuations and contact pressure.

The incidence and trend of geriatric amputations in Taiwan from 1996 to 2013

BACKGROUND

There has been a reported reduction in the incidence of amputation, but it is unclear whether the number of amputations has decreased in the elderly, a cohort that typically has the largest proportion of amputees.

OBJECTIVES

To investigate the incidence proportion and time trends of amputation in patients aged ≥ 65 years in Taiwan.

STUDY DESIGN

A retrospective cohort study from a large national database.

METHODS

The records of patients who underwent an amputation were collected from a nationally representative sample of 1,000,000 enrollees of Taiwan's National Health Insurance program during 1996-2013. The patients were divided into four age groups: ≤64, 65-74, 75-84, and ≥85 years. Joinpoint regression was performed with adjustment for age and sex to identify changes in incidence proportion by year.

RESULTS

During the 18 years, the incidence of upper and lower limb amputation decreased significantly in the total population, with the average annual percentage change (AAPC) of -6.1 and -1.8, respectively. However, in the elderly population over 65 years, the incidence did not decrease significantly for upper minor amputation, lower minor amputation, and major amputation with the AAPC of -1.1, -0.1, and -0.4, respectively. Although not significant, the incidence of major and minor lower limb amputation in the population over 85 years old showed an increasing trend, with the AAPC of 1.2 and 3.2, respectively.

CONCLUSION

During the study period, although the incidence of amputation of the overall population decreased in Taiwan, this trend was not simultaneously observed in the elderly and hence, it should not be ignored.

Balance control deficits in individuals with a transtibial amputation with and without visual input

BACKGROUND

Many individuals with a transtibial amputation (TTA) exhibit balance deficits after limb loss. However, limited evidence exists on balance deficits of individuals with a TTA using hip, knee, and ankle kinematics and center of mass outcomes.

OBJECTIVES

To identify balance control deficits in individuals with a TTA and determine to what extent they are accentuated without visual inputs.

STUDY DESIGN

Cross-sectional.

METHODS

Ten individuals with TTA and 10 healthy controls undertook a biomechanical assessment during a 30-s quiet standing task with eyes open (EO) and eyes closed (EC). The mean trunk, hip, knee, and ankle angles and center of pressure (COP) and center of mass excursions were calculated.

RESULTS

More ankle dorsiflexion was observed for amputated limbs compared with intact lower limbs (mean difference: 5.8-degree, P = 0.031). Less anteroposterior (mean difference: 26.5 mm, P < 0.001) and mediolateral (ML) (mean difference: 4.2 mm, P = 0.042) COP excursions were found for amputated limbs compared with intact lower limbs and for control limbs compared with intact limbs (mean difference: 18.8 mm, P = 0.019). Greater ML COP excursion was found during EC than during EO condition (mean difference: 1.1 mm, P = 0.037).

CONCLUSIONS

Individuals with a TTA presented a greater reliance on the intact lower limb, as highlighted by the greater ankle plantarflexion and anteroposterior and ML COP excursions for intact limbs compared with amputated limbs during quiet standing tasks. During EC condition, both groups exhibited greater ML COP excursions compared with EO condition, suggesting less postural stability. These differences may place them at greater risk of falling.

Using Case-Based Reasoning in a Learning System: A Prototype of a Pedagogical Nurse Tool for Evidence-Based Diabetic Foot Ulcer Care

BACKGROUND

Currently, evidence-based learning systems to increase knowledge and evidence level of wound care are unavailable to wound care nurses in Denmark, which means that they need to learn about diabetic foot ulcers from experience and peer-to-peer training, or by asking experienced colleagues. Interactive evidence-based learning systems built on case-based reasoning (CBR) have the potential to increase wound care nurses' diabetic foot ulcer knowledge and evidence levels.

METHOD

A prototype of a CBR-interactive, evidence-based algorithm-operated learning system calculates a dissimilarity score (DS) that gives a quantitative measure of similarity between a new case and cases stored in a case base in relation to six variables: necrosis, wound size, granulation, fibrin, dry skin, and age. Based on the DS, cases are selected by matching the six variables with the best predictive power and by weighing the impact of each variable according to its contribution to the prediction. The cases are ranked, and the six cases with the lowest DS are visualized in the system.

RESULTS

Conventional education, that is, evidence-based learning material such as books and lectures, may be less motivating and pedagogical than peer-to-peer training, which is, however, often less evidence-based. The CBR interactive learning systems presented in this study may bridge the two approaches. Showing wound care nurses how individual variables affect outcomes may help them achieve greater insights into pathophysiological processes.

CONCLUSION

A prototype of a CBR-interactive, evidence-based learning system that is centered on diabetic foot ulcers and related treatments bridges the gap between traditional evidence-based learning and more motivating and interactive learning approaches.

The Role of Early Revascularization and Biomarkers in the Management of Diabetic Foot Ulcers: A Single Center Experience

Diabetic neuropathy and Peripheral Arterial Disease (PAD) are the main etiological factors in foot ulceration. Herein, we report our experience of diabetic foot ulceration (DFU) management, with an analysis of the relationship between the rate of lower extremity amputation, in persons with infected DFU, after revascularization procedures performed to prevent major amputation. This study highlights the role of different biomarkers, showing their usefulness and potentiality in diabetic foot ulcer management, especially for the early diagnosis and therapy effectiveness monitoring. A retrospective analysis, from September 2016 to January 2021, of diabetic patients presenting diabetic foot with DFU, was performed. All patients were treated with at least one vascular procedure (endovascular, open, hybrid procedures) targeting PAD lesions. Outcomes measured were perioperative mortality and morbidity. Freedom from occlusion, primary and secondary patency, and amputation rate were registered. A total of 267 patients, with a mean age of 72.5 years, were included in the study. The major amputation rate was 6.2%, minor amputation rate was 17%. In our experience, extreme revascularization to obtain direct flow reduced the rate of amputations, with an increase in ulcer healing.

VEGF alleviates lower limb ischemia in diabetic mice by altering muscle fiber types

Lower limb ischemia caused by diabetic foot (DF) is one of the most serious complications of diabetes. The therapeutic role of VEGF in DF is well documented. However, the mechanism for action of VEGF is still not clear. The present study aimed to explore the effects of VEGF-mediated skeletal muscle fiber type switch in angiogenesis and the treatment of DF. C57BL/6 mice housed in cages equipped with a voluntary running wheel were used to access VEGF protein level and citrate synthase activity (by ELISA) as well as muscle fiber type changes (by immunofluorescence) in the gastrocnemius muscle. C57BL/6 mice were fed on a high-fat diet for 6 weeks and then injected with streptozocin to induce diabetic lower limb ischemia model. Control adenovirus (Ad-GFP) or Ad-VEGF-GFP were then injected into the left gastrocnemius of the ischemic diabetic mice. Blood flow perfusion was examined by laser Doppler imaging at 1, 3, 7 and 14 days after adenovirus transduction. On day 14, all mice were anesthetized and sacrificed. VEGF expression levels, citrate synthase activity and muscle fiber type changes in the gastrocnemius muscle were assayed by ELISA and immunofluorescence analysis of myosin heavy chain IIa (MHCIIa) expression, respectively. Transwell assays were performed to determine whether VEGF-treated C2C12 myotubes played a role on tubule formation and migration of HUVECs. It was found that VEGF levels and citrate synthase activity were upregulated after voluntary exercise, along with the increased frequency of oxidized muscle fibers. Notably, adenovirus-mediated VEGF overexpression in the muscle also increased the frequency of oxidized (MHCIIa-positive) muscle fibers, enhanced citrate synthase activity and ameliorated lower limb ischemia in diabetic mice. VEGF treatment enhanced the phosphorylation of PI3K, Akt and AMPK (assayed by western blotting), as well as glucose consumption and metabolism (assayed by western blotting and glucose uptake assay), in the C2C12 myotubes. Interestingly, VEGF-treated C2C12 myotubes promoted the migration and tubule formation of HUVEC cells. The present findings suggest that skeletal muscle fiber conversion might be a potential approach for VEGF-mediated angiogenesis and disease treatment, which may provide new options for the prevention and treatment of DF.

Incidence of interventions for diabetic retinopathy and serious lower-limb complications and its related factors in patients with type 2 diabetes using a real-world large claims database

Aims

To examine the incidence of interventions for diabetic retinopathy and serious limb complications and to elucidate the patient attributes related to the incidence of each intervention based on real-world claims data from Japan.

Materials and methods

A retrospective longitudinal study design involving a 9 year (2009-2018) claims database obtained from the JMDC Inc. Patients with type 2 diabetes aged 20-74 years taking antidiabetic medications were divided into two groups: "patients with newly initiated antidiabetic medication" (Group 1, n = 47,201) and "patients with continuing antidiabetic medication" (Group 2, n = 82,332). The incidence rate for each intervention was analyzed. We also divided Group 1 into the former and latter periods and investigated temporal changes.

Results

The incidences of the first retinopathy intervention (laser photocoagulation, vitrectomy, or intraocular injection), vitrectomy, and lower-limb amputations in Group 1 were 7.46, 2.37, and 0.31 /1000 person-years, respectively. Those in Group 2 were about 1.2-1.5 times higher. Older age, insulin use, and being dependents rather than insured persons were associated with a higher incidence in both groups after adjustment. While the incidence of the interventions for retinopathy hardly changed during the observation period, that of lower-limb amputations decreased by 40%, with less statistical significance (p = 0.11).

Conclusions

We showed the incidences of the first retinopathy interventions and lower-limb amputations and their secular trends in patients with diabetes, stratified by whether the antidiabetic medication was newly initiated or not. Older age, insulin use, and being dependents were risk factors of these interventions for diabetic complications.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-021-00566-7.

Role of Vascular Smooth Muscle Cell Phenotype Switching in Arteriogenesis

Arteriogenesis is one of the primary physiological means by which the circulatory collateral system restores blood flow after significant arterial occlusion in peripheral arterial disease patients. Vascular smooth muscle cells (VSMCs) are the predominant cell type in collateral arteries and respond to altered blood flow and inflammatory conditions after an arterial occlusion by switching their phenotype between quiescent contractile and proliferative synthetic states. Maintaining the contractile state of VSMC is required for collateral vascular function to regulate blood vessel tone and blood flow during arteriogenesis, whereas synthetic SMCs are crucial in the growth and remodeling of the collateral media layer to establish more stable conduit arteries. Timely VSMC phenotype switching requires a set of coordinated actions of molecular and cellular mediators to result in an expansive remodeling of collaterals that restores the blood flow effectively into downstream ischemic tissues. This review overviews the role of VSMC phenotypic switching in the physiological arteriogenesis process and how the VSMC phenotype is affected by the primary triggers of arteriogenesis such as blood flow hemodynamic forces and inflammation. Better understanding the role of VSMC phenotype switching during arteriogenesis can identify novel therapeutic strategies to enhance revascularization in peripheral arterial disease.

Health-related quality of life outcomes and Hospitalization length of stay after micro-fragmented autologous adipose tissue injection in minor amputations for diabetic foot ulceration (MiFrAADiF trial): results from a randomized controlled single-center clinical trial

BACKGROUND

The diabetic foot ulcer (DFU) is a high prevalence complication that significantly impairs the health-related quality of life (HRQoL) and is characterized by prolonged hospital length of stay (LOS). The impact of the micro-fragmented autologous adipose tissue injection at the minor amputation wound in the case of DFU (MiFrAADiF) on HRQoL and LOS compared to the standard care has not been determined yet.

METHODS

This was a two-arm, 6-month, individually randomized controlled single-center clinical trial. A 1:1 randomization to local injection of autologous micro-fragmented adipose tissue (treatment group; n=57) or standard clinical care (control group; n=57) was performed. The primary objective was the HRQoL. The secondary endpoint was the LOS. HRQoL was assessed with the Medical Outcomes Study 36-item Short-Form Health Survey which provides 2 scores focused on physical (PCS) and mental functioning (MCS). The trial was registered in ClinicalTrials.gov (NCT03276312).

RESULTS

The type of treatment (p=0.009) and the time elapsed since surgery (p= 0.0000) demonstrated a significant improvement on PCS. The MCS improvements resulted in a non-significant association with treatment (p= 0.21). The time elapsed since surgery showed a significant influence on the MCS (p= 0.0000). The mean LOS was 16.2 days and 24.4 days for the treatment and the control group respectively (p= 0.025).

CONCLUSIONS

The MiFrAADiF trial demonstrated a significant improvement in terms of physical HRQoL and a significant reduction of the hospital length of stay after injection of micro-fragmented autologous adipose tissue in diabetic patients' minor amputations wound.

Assessment of Simple Bedside Wound Characteristics for a Prediction Model for Diabetic Foot Ulcer Outcomes

BACKGROUND

Evidence-based learning systems built on prediction models can support wound care community nurses (WCCNs) during diabetic foot ulcer care sessions. Several prediction models in the area of diabetic foot ulcer healing have been developed, most built on cardiovascular measurement data. Two other data types are patient information (i.e. sex and hemoglobin A1c) and wound characteristics (i.e. wound area and wound duration); these data relate to the status of the diabetic foot ulcer and are easily accessible for WCCNs. The aim of the study was to assess simple bedside wound characteristics for a prediction model for diabetic foot ulcer outcomes.

METHOD

Twenty predictor variables were tested. A pattern prediction model was used to forecast whether a given diabetic foot ulcer would (i) increase in size (or not) or (ii) decrease in size. Sensitivity, specificity, and area under the curve (AUC) in a receiver-operating characteristics curve were calculated.

RESULTS

A total of 162 diabetic foot ulcers were included. In combination, the predictor variables necrosis, wound size, granulation, fibrin, dry skin, and age were most informative, in total an AUC of 0.77.

CONCLUSIONS

Wound characteristics have potential to predict wound outcome. Future research should investigate implementation of the prediction model in an evidence-based learning system.

Progression to unscheduled hospital admissions in people with diabetes: a qualitative interview study

BACKGROUND

People with diabetes often have difficulty maintaining optimal blood glucose levels, risking progressive complications that can lead to unscheduled care. Unscheduled care can include attending emergency departments, ambulance callouts, out-of-hours care, and non-elective hospital admissions. A large proportion of non-elective hospital admissions involve people with diabetes, with significant health and economic burden.

AIM

To identify precipitating factors influencing diabetes-related unscheduled hospital admissions, exploring potential preventive strategies to reduce admissions.

DESIGN & SETTING

Thirty-six people with type 1 (n = 11) or type 2 (n = 25) diabetes were interviewed. They were admitted to hospital for unscheduled diabetes-related care across three hospitals in Scotland, Northern Ireland, and the Republic of Ireland. Participants were admitted for peripheral limb complications (n = 17), hypoglycaemia (n = 5), hyperglycaemia (n = 6), or for comorbidities presenting with erratic blood glucose levels (n = 8).

METHOD

Factors precipitating admissions were examined using framework analysis.

RESULTS

Three aspects of care influenced unscheduled admissions: perceived inadequate knowledge of diabetes complications; restricted provision of care; and complexities in engagement with self-care and help-seeking. Limited specialist professional knowledge of diabetes by staff in primary and community care, alongside inadequate patient self-management knowledge, led to inappropriate treatment and significant delays. This was compounded by restricted provision of care, characterised by poor access to services - in time and proximity - and poor continuity of care. Complexities in patient engagement, help-seeking, and illness beliefs further complicated the progression to unscheduled admissions.

CONCLUSION

Dedicated investment in primary care is needed to enhance provision of and access to services. There should be increased promotion and earlier diabetes specialist team involvement, alongside training and use of technology and telemedicine, to enhance existing care.

Biofilms in Diabetic Foot Ulcers: Impact, Risk Factors and Control Strategies

Diabetic foot ulcers (DFUs) are a serious complication from diabetes mellitus, with a huge economic, social and psychological impact on the patients' life. One of the main reasons why DFUs are so difficult to heal is related to the presence of biofilms. Biofilms promote wound inflammation and a remarkable lack of response to host defences/treatment options, which can lead to disease progression and chronicity. In fact, appropriate treatment for the elimination of these microbial communities can prevent the disease evolution and, in some cases, even avoid more serious outcomes, such as amputation or death. However, the detection of biofilm-associated DFUs is difficult due to the lack of methods for diagnostics in clinical settings. In this review, the current knowledge on the involvement of biofilms in DFUs is discussed, as well as how the surrounding environment influences biofilm formation and regulation, along with its clinical implications. A special focus is also given to biofilm-associated DFU diagnosis and therapeutic strategies. An overview on promising alternative therapeutics is provided and an algorithm considering biofilm detection and treatment is proposed.

Healing below the ankle is possible in patients with diabetes mellitus and a forefoot gangrene

Background

Forefoot gangrene in patients with diabetes is a severe form of foot ulcers with risk of progress and major amputation. No large cohort studies have examined clinical characteristics and outcome of forefoot gangrene in patients with diabetes. The aim was to examine clinical characteristics and outcome of forefoot gangrene in patients with diabetes admitted to a diabetic foot centre.

Methods

Patients with diabetes and foot ulcer consecutively presenting were included if they had forefoot gangrene (Wagner grade 4) at initial visit or developed forefoot gangrene during follow-up at diabetic foot centre. Patients were prospectively followed up until final outcome, either healing or death. The median follow-up period until healing was 41 (3-234) weeks.

Results

Four hundred and seventy-six patients were included. The median age was 73 (35-95) years and 63% were males. Of the patients, 82% had cardiovascular disease and 16% had diabetic nephropathy. Vascular intervention was performed in 64%. Fifty-one patients (17% of surviving patients) healed after auto-amputation, 150 after minor amputation (48% of surviving patients), 103 had major amputation (33% of surviving patients) and 162 patients deceased unhealed. Ten patients were lost at follow-up. The median time to healing for all surviving patients was 41 (3-234) weeks; for auto-amputated, 48 (10-228) weeks; for minor amputated, 48 (6-234) weeks; and for major amputation, 32 (3-116) weeks.

Conclusion

Healing without major amputation is possible in a large proportion of patients with diabetes and forefoot gangrene, despite these patients being elderly and with extensive co-morbidity.

Clinical Outcome of Transfemoral Direct Socket Interface (Part 2)

BACKGROUND

Amputation at the transfemoral (TF) level reduces the rate of successful prosthetic fitting, functional outcome, and quality of life (QoL) compared with transtibial amputation. The TF socket interface is considered the most critical part of the prosthesis, but socket discomfort is still the most common user complaint. Direct Socket for transfemoral prosthesis users is a novel interface fabrication process where the socket is shaped and laminated directly on the residual limb and delivered in a single visit.

OBJECTIVES

The aim of this study was to investigate if prosthetic users' quality of life (QoL), comfort, and mobility with a Direct Socket TF interface were comparable to their experience with their previous prostheses.

METHODOLOGY

The pre/post design prospective cohort study included 47 subjects. From this cohort, 36 subjects completed the 6-months follow-up (mean age 58 years, 27 males). Outcomes at baseline included EQ-5D-5L®, PLUS-M™, CLASS, ABC, AMPPRO, and TUG. At 6-weeks and 6-months, subjects repeated all measures. Seven Certified Prosthetist (CP) investigators performed observations and data collection at six different sites (from July 2018 to April 2020).

FINDINGS

Results showed significant improvement in all outcome measures for the 36 subjects that completed both 6-weeks and 6-months follow-ups. CLASS sub-scales showed significantly improved stability, suspension, comfort, and socket appearance. Improvement in K-Level and less use of assistive devices were observed with the AMPPRO instrument, indicating improved user mobility and performance. QoL was also increased, as measured in Quality-Adjusted-Life-Years (QALY) from the EQ-5D-5L.

CONCLUSIONS

Evidence from the findings demonstrate that the Direct Socket TF system and procedure can be a good alternative to the traditional method of prosthetic interface delivery.

Lower extremity reamputation in people with diabetes: a systematic review and meta-analysis

In this study, we determined the reamputation-free survival to both limbs and to the contralateral limb only following an index amputation of any-level and assessed whether reamputation rates have changed over time. We completed a systematic search using PubMed and screened a total of 205 articles for data on reamputation rates. We reported qualitative characteristics of 56 studies that included data on reamputation rates and completed a meta-analysis on 22 of the studies which enrolled exclusively participants with diabetes. The random-effects meta-analysis fit a parametric survival distribution to the data for reamputations to both limbs and to the contralateral limb only. We assessed whether there was a temporal trend in the reamputation rate using the Mann-Kendall test. Incidence rates were high for reamputation to both limbs and to the contralateral limb only. At 1 year, the reamputation rate for all contralateral and ipsilateral reamputations was found to be 19% (IQR=5.1%-31.6%), and at 5 years, it was found to be 37.1% (IQR=27.0%-47.2%). The contralateral reamputation rate at 5 years was found to be 20.5% (IQR=13.3%-27.2%). We found no evidence of a trend in the reamputation rates over more than two decades of literature analyzed. The incidence of lower extremity reamputation is high among patients with diabetes who have undergone initial amputations secondary to diabetes, and rates of reamputation have not changed over at least two decades.

Geographical socioeconomic disadvantage is associated with adverse outcomes following major amputation in diabetic patients

OBJECTIVE

Socioeconomic disadvantage is a known predictor of adverse outcomes and amputation in patients with diabetes. However, its association with outcomes after major amputation has not been described. Here, we aimed to determine the association of geographic socioeconomic disadvantage with 30-day readmission and 1-year reamputation rates among patients with diabetes undergoing major amputation.

METHODS

Patients from the Maryland Health Services Cost Review Commission Database who underwent major lower extremity amputation with a concurrent diagnosis of diabetes mellitus between 2015 and 2017 were stratified by socioeconomic disadvantage as determined by the area deprivation index (ADI) (ADI1 [least deprived] to ADI4 [most deprived]). The primary outcomes were rates of 30-day readmission and 1-year reamputation, evaluated using multivariable logistic regression models and Kaplan-Meier survival analyses.

RESULTS

A total of 910 patients were evaluated (66.0% male, 49.2% Black), including 30.9% ADI1 (least deprived), 28.6% ADI2, 19.1% ADI3, and 21.2% ADI4 (most deprived). After adjusting for differences in baseline demographic and clinical factors, the odds of 30-day readmission was similar among ADI groups (P > .05 for all). Independent predictors of 30-day readmission included female sex (odds ratio [OR], 1.45), Medicare insurance (vs private insurance; OR, 1.76), and peripheral artery disease (OR, 1.49) (P < .05 for all). The odds of 1-year reamputation was significantly greater among ADI4 (vs ADI1; OR, 1.74), those with a readmission for stump complication or infection/sepsis (OR, 2.65), and those with CHF (OR, 1.53) or PAD (OR, 1.59) (P < .05 for all).

CONCLUSIONS

Geographic socioeconomic disadvantage is independently associated with 1-year reamputation, but not 30-day readmission, among Maryland patients undergoing a major amputation for diabetes. A directed approach at improving postoperative management of chronic disease progression in socioeconomically deprived patients may be beneficial to reducing long-term morbidity in this high-risk group.

A walking bout reveals altered foot thermodynamics associated with unilateral transtibial amputation among individuals with type 2 diabetes

BACKGROUND

Increased foot temperature among individuals with type 2 diabetes can be predictive of diabetic foot ulcer development. A combination of physiological and mechanical deficiencies may contribute to elevations in intact foot temperature during gait for individuals with type 2 diabetes and transtibial amputation.

OBJECTIVE

This study evaluated plantar foot temperature differences between individuals with type 2 diabetes with and without transtibial amputation. We hypothesized that individuals with transtibial amputation maintain increased foot temperature compared to those without amputation.

STUDY DESIGN

Cross-sectional, case control.

METHODS

A sample of 16 participants with type 2 diabetes and transtibial amputation, and 16 age- and sex-matched participants with type 2 diabetes without amputation were recruited. Foot temperatures were measured during resting, walking, and cooldown periods. Peak temperature, mean temperature, and rate of temperature change were analyzed for each period, and compared between cohorts.

RESULTS

Participants with amputation exhibited increased mean foot temperature while at rest and during walking. Participants without amputation exhibited increased rate of change of foot temperature during walking. No differences in peak temperature or rate of temperature change were observed during the baseline or cooldown periods.

CONCLUSION

The current findings of altered foot temperature for individuals with transtibial amputation and type 2 diabetes suggest a possible reason for the high rates of contralateral limb ulceration and amputation among this population.

Monitored Anesthesia Care Versus General Anesthesia as the Primary Anesthetic for Ankle Amputations

OBJECTIVES

The authors hypothesized that monitored anesthesia care (MAC)-either by local sedation or regional anesthesia (RA)-compared with general anesthesia (GA), would be associated with lower odds of significant 30-day postoperative complications and mortality in patients undergoing an ankle amputation.

DESIGN

Retrospective cohort study.

SETTING

Inpatient.

PARTICIPANTS

The authors used data from patients who underwent ankle amputation from the American College of Surgeons National Surgical Quality Improvement Program registry.

INTERVENTION

RA as primary anesthetic.

MEASUREMENTS AND MAIN RESULTS

A multivariate logistic regression was used to evaluate the association of primary anesthesia type with the outcomes. The regression analysis included all covariates to test the association of the primary exposure variable (anesthesia type) with each outcome of interest. The odds ratio (OR), with associated 95% confidence interval (CI), was reported for each covariate. There were a total of 3,368 patients undergoing guillotine amputation through the tibia/fibula (n = 2,935) or ankle disarticulation (n = 433). Among these patients, 15.5% (n = 491) received MAC as their primary anesthetic. Among all patients, 11.4% (n = 363) experienced a significant postoperative complication. On multivariate logistic regression, MAC was found to decrease odds of postoperative complications (OR 0.57, 95% CI 0.40-0.82, p = 0.002), but not mortality (OR 1.26, 95% CI 0.87-1.84, p = 0.22).

CONCLUSION

This study showed that MAC was associated with improved outcomes, as opposed to GA, as the primary anesthetic in ankle amputations.

History of lower-limb complications and risk of cancer death in people with type 2 diabetes

BACKGROUND

Individuals with diabetes and lower-limb complications are at high risk for cardiovascular and all-cause mortality, but uncertainties remain in terms of cancer-related death in this population. We investigated this relationship in a large cohort of people with type 2 diabetes.

METHODS

We used data from the Action in Diabetes and Vascular Disease: PreterAx and DiamicroN Modified-Release Controlled Evaluation (ADVANCE) study. The primary outcome was adjudicated cancer death; secondary outcomes were overall and site-specific incident cancers, determined according to the International Classification of Diseases Code (ICD-10). We compared outcomes in individuals with (versus without) a baseline history of lower-limb complications (peripheral artery disease (PAD) or sensory peripheral neuropathy) using Cox regression models.

RESULTS

Among 11,140 participants (women 42%, mean age 66 years), lower-limb complications were reported at baseline in 4293 (38%) individuals: 2439 (22%) with PAD and 2973 (27%) with peripheral neuropathy. Cancer death occurred in 316 (2.8%) participants during a median of 5.0 (25th-75th percentile, 4.7-5.1) years of follow-up corresponding to 53,550 person-years and an incidence rate of 5.9 (95% CI 5.3-6.6) per 1000 person-years. The risk of cancer death was higher in individuals with (versus without) lower-limb complication [hazard ratio 1.53 (95% CI, 1.21-1.94), p = 0.0004], PAD [1.32 (1.02-1.70), p = 0.03] or neuropathy (1.41 (1.11-1.79), p = 0.004], adjusting for potential confounders and study allocations. PAD, but not neuropathy, was associated with excess risk of incident cancers.

CONCLUSIONS

PAD and peripheral neuropathy were independently associated with increased 5-year risk of cancer death in individuals with type 2 diabetes. PAD was also associated with increased risk of incident cancers. Our findings provide new evidence on the non-cardiovascular prognostic burden of lower-limb complications in people with type 2 diabetes.

Patient profiles of below knee-amputation following road traffic accidents - An observational study from a level 1 trauma centre in India

BACKGROUND

Primary amputation below the level of the knee joint is the most frequently performed amputation following trauma; however, data about incidence, patient profiling, and causative factors are seldom available in India.

OBJECTIVE

To evaluate the profile and incidence of trauma-related amputations below the level of the knee joint at a level 1 trauma center.

METHODS

An observational study over six months was conducted at a level 1 trauma center of north India. Epidemiological data such as age, sex, occupation, socioeconomic status, mechanism of injury, time of surgery, single or staged procedure, and complications were recorded from the admission files.

OBSERVATIONS

125/3047 (4.1%) trauma patients underwent amputation, of which 32.8% (41 of 125) had amputation below the level of the knee joint. Unilateral transtibial amputation was the most common (85.3%) involving 40/41 males with a mean age of 37.2 years of low socioeconomic status. Road traffic accidents were the most common cause (85.36% of cases). 39 of 41 cases presented within 24 h of injury and underwent surgery within 24 h of presentation. Secondary surgery was needed in 24.4% of the patients and revision amputation was done in only 2.4% (n = 1/41). No patient developed medical complications, and the average hospital stay was 8.7 days with a range from 2 to 14 days.

CONCLUSION

We have documented a significant amputation rate in trauma cases (4.1%) reflecting on the seriousness of patients seen at our center. Most patients are young males at the peak of their productive lives, and from low socioeconomic status. Road Safety is essential, and specialized services for the amputees may be the need of the hour.

Transfemoral Socket Fabrication Method Using Direct Casting: Outcomes Regarding Patient Satisfaction with Device and Services

BACKGROUND

Direct Socket for transfemoral (DS-TF) prosthetic user is a novel method of fabricating a laminated interface on to the residual limb but requires different training, production method and service model than what most prosthetists are familiar with. This method and model may improve patient satisfaction by enabling interface fabrication and delivery in one visit.

OBJECTIVES

Document patient satisfaction regarding DS-TF interface versus the prosthetic users' previous socket in terms of interface function and the clinic service model.

METHODOLOGY

In this longitudinal study (from July 2018 to April 2020), the DS-TF was implemented in six prosthetic clinics across the United States. Certified prosthetists (CP) and assistants were trained using a standard protocol. 47 prosthetic users participated, both those in need of a new socket and those without need. Two modules from the Orthotics and Prosthetics Users' Survey (OPUS), involving questions related to satisfaction with the Device and Services, was used to evaluate each DS-TF user outcome vs. baseline. The only part of the prosthesis that was replaced was the interface, except in 2 cases.

FINDINGS

Each DS-TF interface was fabricated, fit and delivered in a single clinic visit. At 6-months follow-up, 38 users reported an average of 29.8% increase in satisfaction with their new interface compared with original, and a 14.8% increase in satisfaction with the services they received from the clinic in providing of the new prosthesis vs. their original prosthesis. The main outcome increases were between baseline (initial fitting) and 6-week follow-up and remained consistent after 6 months. This improvement was consistent irrespective if the user needed a new socket for clinical reasons or not.

CONCLUSIONS

This study shows that after a standardized training and implementation, the DS-TF fabrication process including a new interface, improves the user's satisfaction with their prosthetic device and services.

Age- and sex-specific incidence of non-traumatic lower limb amputation in patients with type 2 diabetes mellitus in a U.S. claims database

AIM

To estimate age- and sex-specific incidence rates (IRs) of non-traumatic lower limb amputations (LLA) in patients with type 2 diabetes mellitus (T2DM) using a claims database from the United States (US).

METHODS

Patients with T2DM 18 years and older were identified using the Truven Health MarketScan database from January 1, 2007 to September 30, 2018. The overall and age- and sex-specific IRs of all non-traumatic LLA, minor LLA (amputation at or below the ankle), and major LLA (amputation above ankle) were calculated.

RESULTS

Among the 6,117,981 patients with T2DM, 14,627 LLA events occurred (minor LLA; 72.8%; major LLA: 27.2%). The IRs (95% CI) of all LLA, minor LLA, and major LLA per 1000 person-years or PY were 0.86 (0.85, 0.88), 0.63 (0.62, 0.64), and 0.23 (0.23, 0.24), respectively. The IR (95% CI) of all LLA per 1000 PY in males was higher compared to females [1.24 (1.22, 1.26) vs. 0.46 (0.45, 0.48)]. The incidence of all LLA increased with an increasing age (highest IR in age-group of ≥80 years).

CONCLUSIONS

This study identified males and older patients with T2DM at higher risk of developing LLA in the US, warranting further exploration of risk factors of LLA in these subgroups.

Incidence and associated risk factors for limb amputation among sepsis survivors in South Korea

Purpose

Peripheral gangrene (PG) is a known complication requiring limb amputation among sepsis survivors; however, its incidence and associated risk factors remain controversial. We aimed to examine the incidence of limb amputation among sepsis survivors, and to investigate factors independently associated with limb amputation.

Methods

In this population-based cohort study, data obtained from the South Korean national health insurance service database between 2015 and 2016 were analyzed. A sepsis survivor was defined as someone having survived > 90 days after initiation of treatment for sepsis.

Results

Of 19,906 sepsis survivors, 163 (0.8%) had undergone surgical limb amputation. In a multivariable model, male sex (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.26–2.40; P = 0.001), dopamine infusion (OR 1.78, 95% CI 1.22–2.60; P = 0.003), epinephrine infusion (OR 2.04, 95% CI 1.30–3.20; P = 0.002), continuous renal replacement therapy (OR 3.34, 95% CI 2.01–3.20; P < 0.001), diabetes mellitus (DM) without chronic complication (OR 1.73, 95% CI 1.19–2.51; P = 0.004), DM with chronic complication (OR 3.49, 95% CI 2.32–5.26; P < 0.001), and peripheral arterial disease (OR 6.79, 95% CO 3.70–12.46; P < 0.001) were associated with a higher incidence of limb amputation among sepsis survivors.

Conclusions

In South Korea, 0.8% of sepsis survivors underwent limb amputation for the treatment of PG. Furthermore, the incidence of limb amputation was higher among the sepsis survivors having some underlying diseases (DM and peripheral arterial diseases) or receiving certain vasopressor treatments (epinephrine and dopamine).

Electronic supplementary material

The online version of this article (10.1007/s00540-020-02858-9) contains supplementary material, which is available to authorized users.

Using Perforated Liners to Combat the Detrimental Effects of Excessive Sweating in Lower Limb Prosthesis Users

BACKGROUND

Excessive sweating of the residual limb has a substantial effect on the daily activities of people with lower limb amputation. Prosthetic liners offer protection and comfort to sensitive areas but often exacerbate perspiration. They act as insulators, trapping sweat on the skin's surface to the detriment of skin health. Recently, liners with perforations have been developed, allowing the moisture to escape. The goal of this study was to assess the impact of such liners.

METHODS

A sample group of 13 patients with unilateral transtibial amputation, who wore a perforated liner (PL) as part of their current prescription, was compared to 20 control patients who wore non-perforated liners (NPL). During their routine appointments, they completed a survey of scientifically validated outcome measures relating to their limb health, pain and the impact on daily life over a 12-month period.

RESULTS

Patients using the PL had healthier residual limbs, reporting higher scores on questions relating to limb health, experiencing fewer skin issues (p<0.001) and estimating a 61.8% lower rating in perceived sweat (p=0.004). Perhaps consequentially, there was a lower incidence of residual (p=0.012) and phantom (p=0.001) limb pain when compared to the control group. The prevalence of individual issues affecting the residual limbs of PL users was also lower. Of the issues that remained, only 23% were attributed to sweating in PL users, compared to 49% for the NPL group (p=0.066). PL users missed fewer days of work in the year (2.4 vs 11.6, p=0.267) and were also limited on fewer days (1.4 vs 75.4, p=0.009).

CONCLUSION

The use of perforated liners shows much promise within prosthetic care, significantly improving the health of the residual limb. The observed effects on perceived sweat reduction, residual skin health, pain levels and patient limitation suggest that perforated liners are highly beneficial to patients.

Cortical and medullary morphology of the tibia

Bone resorption caused by stress shielding and insufficient bone-implant contact continues to be problematic for orthopedic endoprostheses that utilize osseointegration (OI) for skeletal fixation. Morphologic analyses have helped combat this issue by defining anatomic parameters to optimize endoprosthesis loading by maximizing bone-implant contact. These studies have not typically included diaphyseal medullary morphology, as this region is not pertinent to total joint replacement. To the contrary, percutaneous OI endoprostheses for prosthetic limb attachment are placed in the diaphysis of the long bone. This study examined the cortical and medullary morphology of 116 fresh-frozen human cadaveric tibia using computed tomography. Anatomic landmarks were selected and custom MATLAB scripts were used to analyze the cross-sectional cortical and medullary morphology normalized to biomechanical length (BML). BML measured the distance between the tibial plateau and the tibial plafond. Properties such as cortical thickness, medullary diameter, and circularity of the medullary canal were quantified. We tested the influence of sex and laterality on morphology, and examined variations along the length of the bone. Results showed that while both sex and laterality impacted the location of anatomic landmarks, only sex influenced cross-sectional morphology. Overall, morphology significantly affected shape along the length of the bone for all examined properties except medullary circularity. This analysis found that distal to 35% BML, the canal is conducive to a circular implant, with medullary diameter ranging from 13 to 32 mm between 20 and 80% BML. A large size range is necessary for sufficient implant contact in order to accommodate residual limb length after amputation.