Foot ulcerations are one of the most common and dangerous complications associated with chronic diabetes mellitus. Many studies have focused on neuropathy, in conjunction with elevated ground reactive forces, as the principal cause of these ulcerations. The authors discuss the mechanical cause of diabetic ulcerations at the cellular level. It is hypothesized that increased rate of tissue deformation associated with foot slap secondary to progressive motor neuropathy is the actual culprit, and not the magnitude of local pressure applied. The authors present a cellular model that shows that high rates of tissue deformation may result in elevated intracellular calcium concentrations, which may lead to cellular death, while comparable loads gradually applied do not. Furthermore, there is no significant difference in the response observed at 5 psi and 10 psi. Based on these findings, it is hypothesized that techniques such as ankle foot orthoses, which control the velocity of foot strike, may be useful in treating diabetic foot ulcerations.
BACKGROUND: Diabetic Foot Osteomyelitis (DFO) is a common infection where treatment involves multiple services including Infectious Disease (ID), Podiatry, and Pathology. Despite its ubiquity in the hospital, consensus on much of its management is lacking. METHODS: Representatives from ID, Podiatry, and Pathology interested in quality improvement (QI) developed multidisciplinary institutional recommendations culminating in an educational intervention describing optimal diagnostic and therapeutic approaches to DFO. Knowledge acquisition was assessed by pre- and post-intervention surveys. Inpatients with forefoot DFO were retrospectively reviewed pre- and post- intervention to assess frequency of recommended diagnostic and therapeutic maneuvers, including appropriate definition of surgical bone margins, definitive histopathology reports, and unnecessary intravenous antibiotics or prolonged antibiotic courses. RESULTS: A post-intervention survey revealed significant improvements in knowledge of antibiotic treatment duration and the role of oral antibiotics in managing DFO. There were 104 consecutive patients in the pre-intervention cohort (4/1/2018-4/1/2019) and 32 patients in the post-intervention cohort (11/5/2019-03/01/2020), the latter truncated by changes in hospital practice during the COVID-19 pandemic. Non-categorizable or equivocal pathology reports decreased from pre-intervention to post-intervention (27.0% vs 3.3%, respectively, P=0.006). We observed non-significant improvement in correct bone margin definition (74.0% vs 87.5%, p=0.11), unnecessary PICC line placement (18.3% vs 9.4%, p=0.23), and unnecessary prolonged antibiotics (21.9% vs 5.0%, p=0.10). Additionally, by working as an interdisciplinary group, many solvable misunderstandings were identified, and processes were adjusted to improve the quality of care provided to these patients. CONCLUSIONS: This QI initiative regarding management of DFO led to improved provider knowledge and collaborative competency between these three departments, improvements in definitive pathology reports, and non-significant improvement in several other clinical endpoints. Creating collaborative competency may be an effective local strategy to improve knowledge of diabetic foot infection and may generalize to other common multidisciplinary conditions.
Patient education is a fundamental aspect of the management of foot ulcers in the patient with diabetes mellitus. Preventive measures have to be focused on the individual risk profile of the patient and on the chronology of appearance of symptoms. Teaching issues need to be adapted into the following three stages: A) before: prevention of foot ulceration in the at-risk patient; B) acute: prevention of extension of an existing ulcer; and C) after: prevention of recurrence.
Streptococcus anginosus (SAG) is a known human pathogen and member of the Streptococcus milleri group. SAG is a known bacterial cause of soft-tissue abscesses and bacteremia and is an increasingly prevalent pathogen in infections in patients with cystic fibrosis. We describe a rare case of SAG as an infectious agent in a case of nonclostridial myonecrosis with soft-tissue emphysema. This is the only case found in the literature of SAG cultured as a pure isolate in this type of infection and was associated with a prolonged course of treatment in an otherwise healthy patient.
The authors compare the level of foot amputation by age, prevalence of arterial disease as a precipitating factor, gender, and ethnicity in persons with diabetes mellitus. Medical records were abstracted for each hospitalization for a lower extremity amputation from January 1 to December 31, 1993, in six metropolitan statistical areas in south Texas. Amputation level was defined by ICD-9-CM codes and were categorized as foot, leg, and thigh amputations. Foot-level amputations were further subcategorized as hallux or first ray, middle, fifth, multiple digit or ray, and midfoot amputations. Only the highest amputation level for each individual was used in the analysis. Of 1,043 subjects undergoing a lower extremity amputation in south Texas in the year 1993, 477 received their amputation at the level of the foot. African-Americans requiring a foot-level amputation were at significantly higher risk to undergo a midfoot-level amputation than was the rest of the population. Nearly 40% of all subjects undergoing a foot-level amputation had a previous history of amputation. However, nearly 40% of subjects undergoing foot amputations had not been diagnosed either before or during admission with peripheral arterial occlusive disease, suggesting a causal pathway dependent primarily on neuropathy. This implies that better screening of diabetic patients with appropriate risk-directed treatment at the primary care level may significantly impact the large number of preventable diabetes-related lower extremity amputations.
There is evidence to indicate that therapeutic footwear can help prevent lower extremity amputation in patients with diabetes. The primary means of preventing amputation is to protect the insensitive foot from unnoticed trauma and excessive plantar pressures that occur during walking. The specific prescription of the shoe will depend on many foot risk criteria, but particularly on the patient's level of sensation, history of ulceration, and the amount of foot deformity. This article describes the type of footwear recommended for each of these increasing levels of foot risk categories.