Finite element-based method for determining an optimal offloading design for treating and preventing heel ulcers.

Area of Science:

• Biomechanics
• Diabetic Foot Complications
• Finite Element Analysis

Background:

• Diabetic heel ulceration is a severe complication requiring custom offloading footwear.
• Current insoles with holes reduce local load but neglect peripheral stress.
• Optimal offloading hole design lacks quantitative assessment and guidelines.

Purpose of the Study:

• To develop a novel method for assessing mechanical loading on human heel soft tissues.
• To analyze the biomechanical efficiency of finite-element footwear configurations with varying offloading hole geometries.
• To identify optimal design parameters for offloading insoles to minimize load on ulcer sites and peripheries.

Main Methods:

• A novel method was developed to determine volumetric exposure to mechanical loading during walking.
• Two volumes of interest (VOIs) were defined: high-risk ulceration areas and surrounding soft tissues.
• 150 finite-element footwear configurations with varied hole radius, radius of curvature (ROC), and depth were analyzed.

Main Results:

• Two combinations of offloading parameters were found to minimize heel loads in both VOIs.
• Combination 1: Large offloading radius, large ROC, and large depth.
• Combination 2: Large offloading radius, large depth, and relatively small ROC.

Conclusions:

• A novel practical scientific analysis method was developed to evaluate offloading footwear.
• This method considers both the ulcer site and peripheral areas for comprehensive load assessment.
• The approach has the potential to optimize offloading solution development, improving diabetic ulcer prevention and treatment.