Comparative Finite-Element Analysis for Defect Reconstruction with Rhomboid Flaps

Abstract

Objectives:

To view the utility of comparative 2D finite element analysis (FEA) of rhomboid flap models in analyzing how varying skin stiffness and directionality affects closure of a facial defect.

Methods:

Two-dimensional (2D) finite element models based on prior validated 2D. Nonlinear hyperelastic human skin models of rhomboid surgical flaps were parameterized for reconstruction of a 2 × 2 cm facial defect. Skin stiffness and directionality were varied to simulate several real-patient factors such as age, radiation, sex, etc. ANSYS 12.1 was used to compute the stress/strain and reaction force results.

Results:

The challenges of defect closure often include intrinsic factors of a patient’s skin. As skin stiffness and directionality vary, the stress/strain patterns vary accordingly. FEA gives surgeons the ability to visually see how certain patient-specific skin factors affect closure of a defect, allowing for anticipation of challenges such as dog-earing or high strain fields near critical structures (eye, ear, and hairline).

Conclusions:

The utility of finite element models for analyzing and planning pre-surgical endeavors has been well-documented. Our study is the first of its kind for comparative surgical planning for varying skin conditions.