Prediction of diabetic foot ulcer progression: a computational study

Abstract

The development of foot ulcers is a common consequence of severe diabetes. Due to vascular disorders and impeded healing caused by the disease, most foot ulcers have been reported to be affected by body weight and progress with time. Also, abnormal distribution of plantar pressures has been observed to cause the formation of additional ulcers, which may collectively lead to traumatic amputations. While a study of such pathophysiology is not possible through experiments, a few computational modelling works have investigated diabetic foot ulcers. To date, ulcers with a few sizes and locations have been studied, and their effect on the plantar stresses has been quantified. In this work, we have attempted to study the effect of all possible ulcer locations on the generated plantar peak stresses and peak stress locations where additional ulcers may form. Also, the effect of ulcer location on the possible ulcer growth was investigated. A full-scale foot model was developed and a total of 52 ulcer locations were simulated separately, with standing and walking loads. The generated stresses were normalised with the foot size and statistically analysed to develop novel formulations for predicting peak plantar stresses and their locations for any known ulcer location. The results from this study are anticipated to provide important guidelines to doctors and medical practitioners for predicting foot ulcer progression in diabetic patients with existing ulcers and allow the administration of timely preventive interventions.

Biomechanical modeling of novel high expansion auxetic skin grafts

“…While the regions surrounding the incisions for all the skin graft models were meshed with quadratic elements, the remaining regions were meshed using linear elements of lower order. This was in line with several previous works employing tetrahedral elements for studying the deformation of intricate human soft tissue models and their comparison with clinical observations 38–41 . Optimal computational meshes were generated using the hybrid combination of quadratic and linear elements with element sizes ranging from 0.4 to 1 mm depending upon the skin graft model, and number of elements above 10,000.A detailed mesh convergence study was conducted with six different meshes for each skin graft model.…”

“…8 A few limitations of this work should be acknowledged. We considered the skin as an isotropic and elastic material model in line with previous literature works, 34,39,41 and to focus primarily on studying the effect of auxetic graft patterns on two-layer skin. In real, the skin consists of several layers of fibers, follicles, vessels, fat, etc.…”

“…This was in line with several previous works employing tetrahedral elements for studying the deformation of intricate human soft tissue models and their comparison with clinical observations. [38][39][40][41] Optimal computational meshes were generated using the hybrid combination of quadratic and linear elements with element sizes ranging from 0.4 to 1 mm depending upon the skin graft model, and number of elements above 10,000.A detailed mesh convergence study was conducted with six different meshes for each skin graft model. Three deformation values corresponding to 50%, 100%, and 200% strains were applied to each mesh and the mesh which the minimum variations in results (i.e., maximum stress within 5%) with further increase in the number of elements, was selected as the optimal mesh for any particular graft model.…”

Traction performance modeling of worn footwear with perpendicular treads

“…Beyond this, hyperelastic modelling was invoked to simulate polymeric nonlinear stiffening effects. All the outsoles were meshed with 10-node SOLID 187 tetrahedral elements to facilitate ease in mesh convergence and enhance the models' accuracy [41][42][43]. The outsoles were computationally warped at an angle of 17°and a force of 275 N was evenly applied over the upper surface of the outsole model.…”

Vitamin D Deficiency as a Possible Cause of Type 1 Diabetes in Children and Adolescents up to 15 Years Old: A Systematic Review

“…Most of the symptoms are not severe, but over time, they can cause damage or even complete destruction of an organ, resulting in irreversible conditions such as blindness, amputation, stroke, heart attack, kidney failure, and death [ 3 , 4 ]. Computational techniques used for diabetes show that DT1 is also associated with increased risk of fracture in human bone [ 5 ] and foot ulceration [ 6 , 7 ]. More than 90% of newly diagnosed people with DT1 have measurable antibodies that act against specific beta-cells proteins, such as insulin.…”