David G. Armstrong

Keck School of Medicine of USC · Surgery

Objectives: This study aims to examine the association between state Medicaid coverage of podiatry services and the outcomes of beneficiaries with new diabetic foot ulcers (DFUs). Methods: Medicaid beneficiaries who developed a DFU between 2010 and 2015 were identified using the PearlDiver claims database. The states were categorized into covered s...

Diabetic foot ulcers (DFUs) represent a serious complication of diabetes with high incidence, requiring intensive treatment, prolonged hospitalization, and high costs. It poses a severe threat to the patient's life, resulting in substantial burdens on patient and healthcare system. However, the therapy of DFUs remains challenging. Therefore, explor...

Purpose The recent SENZA-PDN study showed that high-frequency (10kHz) spinal cord stimulation (SCS) provided significant, durable pain relief for individuals with painful diabetic neuropathy (PDN), along with secondary benefits, including improved sleep quality and HRQoL. Given that metabolic factors and chronic neuropathic pain are related, we eva...

Diabetic foot complications that lead to lower extremity amputations pose a significant challenge to the entire global health system. In this multicentre clinical trial, 26 patients with chronic Wagner one diabetic foot ulcers (DFUs) were treated with a unique human keratin matrix graft applied either weekly or bi‐weekly, in addition to standard of...

OBJECTIVE Diabetes affects 537 million people globally, with 34% expected to develop foot ulceration in their lifetime. Diabetes-related foot ulceration causes strain on health care systems worldwide, necessitating provision of high-quality evidence to guide their management. Given heterogeneity of reported outcomes, a core outcome set (COS) was de...

Aims Incorrectly fitting footwear (IFF) poses a risk of trauma to at‐risk feet with diabetes. The aim of this systematic review was to summarise and assess the evidence that IFF is a statistically significant cause of ulceration. Methods We searched PubMed, Scopus, Web of Science and Google Scholar for English‐language peer‐reviewed studies report...

Objective: Hard-to-heal diabetic foot ulcers (DFUs) are associated with higher mortality rates and an increased medical burden for patients. ON101, a new topical cream, exhibited better healing efficacy than the control dressing in a Phase III trial. In this post-hoc analysis, we further identify whether ON101 can improve the healing of ulcers wit...

Diabetic foot ulcers (DFUs) significantly affect the lives of patients and increase the risk of hospital stays and amputation. We suggest a remote monitoring platform for better DFU care. This system uses digital health metrics (scaled from 0 to 10, where higher scores indicate a greater risk of slow healing) to provide a comprehensive overview thr...

Hand infection is a rare complication in patients with diabetes. Its clinical outcomes depend on the severity of hand infection caused by bacteria, but the difference in bacterial species in the regional disparity is unknown. The purpose of this study was to explore the influence of tropical and nontropical regions on bacterial species and clinical...

Significance: The Wound Healing Foundation recognized the need for consensus-based unbiased recommendations for the treatment of wounds. As a first step, a consensus on the treatment of chronic wounds was developed and published in 2022.(1) The current publication on acute wounds represents the second step in this process. Acute wounds may result...

Diabetic foot ulcers (DFUs) significantly affect the lives of patients and increase the risk of hospital stay and amputation. We suggest a remote-monitoring platform for better DFU care. This system uses digital health metrics (scaled from 0 to 10, where higher scores indicate a greater risk of slow healing) to provide a comprehensive overview thro...

Background This study examined the efficacy of an interdisciplinary limb preservation service (LPS) in improving surgical outcomes for diabetic foot ulcer (DFU) patients compared to traditional care. Methods Data from January 1, 2017 to September 30, 2020 were retrospectively reviewed. An interdisciplinary LPS clinic began on August 1, 2018, coexi...

Objective To predict the risk of hospital-acquired pressure injury using machine learning compared with standard care. Design We obtained electronic health records (EHRs) to structure a multilevel cohort of hospitalised patients at risk for pressure injury and then calibrate a machine learning model to predict future pressure injury risk. Optimisa...

As the incidence of diabetic foot ulcers (DFU) increases, better treatments that improve healing should reduce complications of these ulcers including infections and amputations. We conducted a randomized controlled trial comparing outcomes between a novel purified reconstituted bilayer membrane (PRBM) to the standard of care (SOC) in the treatment...

Objective: To compare the effectiveness of cellular tissue products (CTP) versus standard care in U.S. Medicare beneficiaries with diabetic lower extremity ulcers (DLEUs) or venous leg ulcers (VLUs). Approach: We performed a retrospective cohort study using real-world evidence from U.S. Medicare claims for DLEUs or VLUs between 2016 and 2020. There...

Background: The purpose of this study was to determine the association of preulcerative foot care and outcomes of diabetic foot ulcerations (DFUs). Methods: This retrospective cohort study using the Mariner all-payers claims data set included participants with a new DFU from 2010 to 2019. Patients were stratified into two cohorts (foot care and con...

Background Chronic wound management in low-resource settings deserves special attention. Rural or under-resourced settings (ie, those with limited basic needs/healthcare supplies and inconsistent availability of interprofessional team members) may not be able to apply or duplicate best practices from urban or abundantly resourced settings. Objecti...

Background Painful diabetic neuropathy (PDN) can result in the loss of protective sensation, in which people are at twice the likelihood of foot ulceration and three times the risk of lower extremity amputation. Here, we evaluated the long-term effects of high-frequency (10 kHz) paresthesia-independent spinal cord stimulation (SCS) on protective se...

Purpose: Hand infection is a rare complication in patients with diabetes. Its clinical outcomes depend on the severity of hand infection caused by bacteria, but the difference in bacterial species in the regional disparity is unknown. The purpose of this study was to explore the influence of tropical and nontropical regions on bacterial species and...

Pre- and post-debridement spatial tissue oxygenation of diabetic foot ulcers were acquired using a smartphone-based NIRS device. Upon removing unviable tissue around the wounds, the tissue oxygenation increased, as objectively observed in this study.

Tissue oxygenation and thermal maps together were used to monitor the healing status in diabetic foot ulcers (DFUs) using smartphone-based NIRS and thermal imaging devices. These combined physiological measurements differentiate healing and non-healing DFUs.

Newly revised to reflect the latest Standards of Care in Diabetes, this fourth edition of Clinical Care of the Diabetic Foot is an essential guide for all clinicians, healthcare providers, and educators who help people with diabetes avoid and manage this challenging complication. This new edition addresses the full scope of treatment, including: Pa...

Newly revised to reflect the latest Standards of Care in Diabetes, this fourth edition of Clinical Care of the Diabetic Foot is an essential guide for all clinicians, healthcare providers, and educators who help people with diabetes avoid and manage this challenging complication. This new edition addresses the full scope of treatment, including: Pa...

Newly revised to reflect the latest Standards of Care in Diabetes, this fourth edition of Clinical Care of the Diabetic Foot is an essential guide for all clinicians, healthcare providers, and educators who help people with diabetes avoid and manage this challenging complication. This new edition addresses the full scope of treatment, including: Pa...

Despite the known higher risk of cardiovascular disease in individuals with type 2 diabetes, the pathophysiology and optimal management of diabetic foot ulcers (DFUs), a leading complication associated with diabetes, is complex and continues to evolve. Complications of type 2 diabetes, such as DFUs, are a major cause of morbidity and mortality and...

Background: Over half of the 100,000 lower extremity amputations in the United States every year are related to complications of diabetes mellitus, yet mental health and/or depression are not routinely addressed as an underlying contributor. To prevent amputations, the Veterans Health Administration (VHA) utilizes the PAVE program which classifies...

The inaugural expert consensus and guidance for Nutrition Interventions in Adults with Diabetic Foot Ulcers (DFU) have been welcomed by clinicians internationally. This short report aimed to determine how the macronutrient and micronutrient status of individuals living with DFU compared to the American Limb Preservation Society Nutrition Interventi...

Background Diabetic foot ulcers (DFUs) pose a significant clinical challenge for providers and patients, and often precede devastating complications such as infection, hospitalization, and amputation. Therefore, advanced treatment options are needed to facilitate the healing of chronic DFUs and improve outcomes in this high-risk population. Cryopre...

Disclosure: I.K. Bolakale-Rufai: None. S. French: None. J.C. Arias: None. K. Concha-Moore: None. T. Tan: None. D.G. Armstrong: None. A. Mazhar: Employee; Self; Modulim. C.C. Weinkauf: None. Background: Microvascular disease (MVD) describes systemic changes in the small vessels (∼100 υm diameter) that impair tissue oxygenation and perfusion. Emergin...

Introduction We evaluated the outcomes associated with initial antibiotic management strategies for infected diabetic foot ulcers (DFU) diagnosed in an outpatient multidisciplinary center. Methods and Materials Consecutive outpatient individuals with infected DFU, stratified according to Infectious Diseases Society of America infection severity, w...

Background Proper identification of the polymicrobial microorganisms in patients with limb-threatening diabetic foot ulcers (LTDFUs) using conventional culture is insufficient. This prospective study evaluates the potential value of adjuvant molecular testing assisting in identify fastidious micro-organisms in LTDFUs compared to standard treatment...

Diabetic foot ulcers (DFUs) affect one in every three people with diabetes. Imaging plays a vital role in objectively complementing the gold-standard visual yet subjective clinical assessments of DFUs during the wound treatment process. Herein, an overview of the various imaging techniques used to image DFUs is summarized. Conventional imaging moda...

Diabetes-related foot infection (DFI) can devastate patient’s mobility and quality of life, with many patients fearing lower limb amputation more than death. This disease disproportionately affects marginalized communities and social barriers frequently complicate treatment. Multidisciplinary DFI teams can reduce major (above-ankle) amputations, ye...

Introduction Indigenous peoples in Canada face a disproportionate burden of diabetes-related foot complications (DRFC), such as foot ulcers, lower extremity amputations (LEA), and peripheral arterial disease. This scoping review aimed to provide a comprehensive understanding of DRFC among First Nations, Métis, and Inuit peoples in Canada, incorpora...

Most conventional therapies have limitations in the repair of complex wounds caused by chronic inflammation in patients with diabetic foot ulcers (DFUs). In response to the demand for more biotechnology strategies, bioprinting has been explored in the regeneration field in recent years. However, challenges remain regarding the structure of complex...

People with a history of diabetic foot ulcers (DFUs) experience diminished health-related quality of life and are at a 40% annual risk of DFU recurrence. Due to a fear of DFU recurrence, people in DFU remission participate less in physical activity and moderate-intensity exercise when compared to people with diabetes who have not had wounds. There...

A novel autologous heterogeneous skin construct (AHSC) was previously shown to be effective versus standard of care (SOC) treatment in facilitating complete wound healing of Wagner 1 diabetic foot ulcers in an interim analysis of 50 patients previously published. We now report the final analysis of 100 patients (50 per group), which further support...

Importance: Approximately 18.6 million people worldwide are affected by a diabetic foot ulcer each year, including 1.6 million people in the United States. These ulcers precede 80% of lower extremity amputations among people diagnosed with diabetes and are associated with an increased risk of death. Observations: Neurological, vascular, and biom...

Objective: Up to 9 million Americans have painful diabetic neuropathy (PDN), which can be debilitating. For PDN patients, 10 kHz SCS has been shown to provide mean pain relief of 77% at 24 months (24M), and here we report secondary, novel potential benefits for A1C and body weight. Methods: Subjects received a 10 kHz SCS implant plus medical manage...

Diabetic foot ulcers (DFUs) are serious complication of diabetes. Offloading devices treat DFUs by distributing force and reducing pressure across the wound. Adhering to appropriate use of offloading devices is a key strategy to promote DFU healing. However, some people who are highly adherent to offloading device use still do not heal. Factors suc...

Background: Proper debridement of the wound base is critical to facilitate wound granulation and closure in non-healing diabetic foot ulcers(DFUs). A unique micro water jet device has been developed and recently granted breakthrough designation for treatment of DFUs by the Foot and Drug Administration(FDA) that precisely cleans acute and chronic wo...

Aims: Offloading mechanical tissue stress is arguably the most important of multiple interventions needed to heal diabetes-related foot ulcers. This is the 2023 International Working Group on the Diabetic Foot (IWGDF) evidence-based guideline on offloading interventions to promote healing of foot ulcers in persons with diabetes. It serves as an up...

Background Sphingosine-1-phosphate (S1P), a key regulator of vascular homeostasis and angiogenesis, is enriched in exosomes derived from platelet-rich plasma (PRP-Exos). However, the potential role of PRP-Exos-S1P in diabetic wound healing remains unclear. In this study, we investigated the underlying mechanism of PRP-Exos-S1P in diabetic angiogene...

Background: More than 86,000 Americans with type 2 diabetes mellitus (T2DM) undergo nontraumatic lower-extremity amputations annually. The opioid-prescribing practice of podiatric surgeons remains understudied. We hypothesized that patients with T2DM who undergo any forefoot amputation while using antidepressant medication will have reduced odds of...

Adherence to using offloading treatment is crucial to healing diabetes-related foot ulcers (DFUs). Offloading adherence is recommended to be measured using objective monitors. However, self-reported adherence is commonly used and has unknown validity and reliability. This study aimed to assess the validity and reliability of self-reported adherence...

Background: Peripheral artery disease (PAD) is linked with an increased risk of lower extremity amputation and multiple socioeconomic factors attenuate this risk. Prior studies have demonstrated increased rates of amputation in PAD patients with suboptimal or no insurance coverage. However, the impact of insurance loss in PAD patients with pre-exi...

There are currently over 80 biomaterials derived from autologous, allogeneic, synthetic and xenogeneic sources, or a combination of any or all these types of materials, available for soft-tissue coverage to effect wound closure. Often generically referred to as cellular and/or tissue-based products (CTPs), they are manufactured under various trade...

Background: Experiencing a hyperglycaemic crisis is associated with a short- and long-term increased risk of mortality. We aimed to develop an explainable machine learning model for predicting 3-year mortality and providing individualized risk factor assessment of patients with hyperglycaemic crisis after admission. Methods: Based on five repres...

People with diabetic foot ulcers (DFUs) are commonly prescribed offloading walkers, but inadequate adherence to prescribed use can be a barrier to ulcer healing. This study examined user perspectives of offloading walkers to provide insight on ways to help promote adherence. Participants were randomized to wear: (1) irremovable, (2) removable, or (...

This manuscript constitutes a commentary on: "Retrospective cohort study of long-term outcomes and prognostic factors for survival after lower extremity amputation in patients with diabetes" by Vuorlaakso et al. (2023). We aim to contribute to the reflection of their findings to support the comprehensive management of vulnerable individuals with mu...

Background: Pressure injuries (PIs) impose a substantial burden on patients, caregivers, and healthcare systems, affecting an estimated 3 million Americans and costing nearly $18 billion annually. Accurate pressure injury staging remains clinically challenging. Over the last decade, object detection and semantic segmentation have evolved quickly w...

Objective: Evaluate the inter- and intra-rater reliability of a wound assessment tool in iPhone 12 and 13 mini modalities against a validated iPad mini/Structure Sensor configuration. Approach: We assessed a wound measurement application (eKare inSight) for result consistency in patients presenting with wounds. Assessments were analyzed using a...

Elevated levels of bacteria, including biofilm, increase the risk of chronic wound infection and inhibit healing. Addressing asymptomatic high bacterial loads is challenged by a lack of clinical terminology and diagnostic tools. This post‐hoc multicenter clinical trial analysis of 138 diabetic foot ulcers investigates fluorescence (FL)‐imaging role...

The relationship between pain/disability and angular deviation of the hallux valgus (HV), and the impact of orthotic use, laterality, and pain variability on treatment outcomes remain unclear. This was explored in post hoc analyses of a placebo-controlled trial of abobotulinumtoxinA (aboBoNT-A; Dysport®) for HV-associated pain (NCT03569098). The pr...

The objective of this study was to assess the overall differences in the standard of preventive foot care for patients at risk of diabetic foot ulceration and to identify specific demographic factors affecting these health care practices, including race and ethnicity. The National Health and Nutrition Examination Survey data for 2011 to 2018 were a...

Importance Venous leg ulcers (VLU) are the most common cause of lower extremity ulceration that commonly occur among older individuals and are characterized by a slow healing trajectory and frequent recurrence; in the United States, VLUs affect more than 600 000 people per year with an estimated cost of $3.5 billion. Clinical trial data show that e...

Individuals with type 2 diabetes mellitus (T2DM) have an increased risk of bone metabolic disorders and bone fracture due to disease progression and clinical treatment. The effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors, now greatly prescribed for the treatment of T2DM, on bone metabolism is not clear. This study aimed to explore the p...

Objective Frailty represents a state of multisystem impairment that may adversely impact people presenting with chronic limb-threatening ischemia (CLTI) and diabetes-related foot ulcers (DFUs). The aim of this systematic review was to explore the association between frailty and outcomes from CLTI and DFUs. Methods We performed a systematic literat...

Diabetic foot complications are increasingly burdensome for patients, clinicians, and society. Development of innovative therapies to support good quality basic care is a priority among those with an interest in this area. One of these involves scanning and printing tissues to match and conform to a defect (so-called 3D printing). Methods: A sing...

Background A comprehensive insight into the effect of longstanding diabetes mellitus and neuropathy on foot joint kinetics during walking is lacking. Our goal was to assess the in-vivo kinetics of major foot joints in persons with diabetes. Methods Three groups, matched for age, sex and walking speed were recruited in this study: 1) people with di...

Aims To disclose prevalence, demographic, foot characteristics as well as management and lower-extremity amputations (LEAs) of subjects with end-stage renal disease (ESRD) on diabetic foot diseases (DFDs). Methods Data were derived from the Taiwan National Health Insurance Research Database between 2004 and 2017. DFDs were defined as ulcers, infec...

The frequency of chronic cutaneous wounds are sharply increasing in aging populations. Patients with age-related diseases, such as diabetes, tumors, renal failure and stroke are prone to soft tissue and skin injury, compounded by slowed healing in aging. Imbalance of wound inflammation, loss of growth factor secretion, and impairment of tissue repa...

Artificial intelligence can use real-world data to create models capable of making predictions and medical diagnosis for diabetes and its complications. The aim of this commentary article is to provide a general perspective and present recent advances on how artificial intelligence can be applied to improve the prediction and diagnosis of six signi...

There are few data comparing outcomes after hallux amputation or partial first ray resection after diabetic foot ulcer (DFU). In a similar context, the choice to perform one of these two surgeries is attributable to clinician preference based on experience and characteristics of the patient and the DFU. Therefore, the purpose of this study was to d...

Nearly a decade ago, the Society for Vascular Surgery (SVS)'s wound, ischemia, and foot Infection (WIfI) classification was first developed to help assess overall limb threat. However, managing conditions such as diabetic foot ulcer and chronic limb-threatening ischemia can be complex. For instance, certain investigative findings might initially be...

Background: An aseptically processed dehydrated human amnion and chorion allograft(dHACA) without terminal sterilization has been shown to improve healing rates in chronic wounds. This randomized controlled trial(RCT) evaluated the safety and effectiveness of weekly and biweekly applications of dHACA plus Standard of Care (SOC) compared to SOC alo...