Exploring How Subcutaneous Fat Prevents Pressure Sores: A Study Using Ultrasound and Finite Element Analysis

Aims: This study investigates the protective role of subcutaneous fat in preventing pressure sores, integrating ultrasound and finite element analysis (FEA) to understand the biomechanical mechanisms. It aims to explore the correlation between subcutaneous fat thickness and pressure sore risk as indicated by Braden scale scores. Materials and Methods: A total of 100 bedridden patients from the Spine Ward and Pulmonary Medicine intensive care unit were enrolled. Subcutaneous fat thickness in the sacral region was measured using ultrasound, and Braden scale scores were recorded. FEA was used to simulate stress and strain distributions in the muscle and fat layers for varying fat thickness. Statistical analysis was performed using analysis of variance, post hoc Tukey test, and Pearson's chi-square test to correlate fat thickness with mechanical parameters. Results: The results demonstrated a significant negative correlation between subcutaneous fat thickness and pressure sore risk. Patients with lower Braden scale scores (higher risk) had thinner subcutaneous fat. FEA models showed that increased fat thickness reduced maximum total deformation, equivalent stress, and shear stress in muscle and bone tissues. Conclusion: Subcutaneous fat plays a crucial protective role in preventing pressure sores by reducing mechanical strain on tissues. This study highlights the potential for using subcutaneous fat thickness measurements as a predictive tool for pressure sore risk and suggests the exploration of fat grafting as a preventive strategy.