Process of 3-hinge patterns’ detection. (a) Initial state of the meshed area created by triangular mesh. (b) The deformed coordinates of the cortical surface in ABAQUS are reconstructed in MATLAB. (c) The constructed surface is visualized by Paraview software. (d) A developed algorithm detects path lines and center points of 3-hinge patterns. Blue to red shows a transition from convex curvature to concave curvature.