Measurement of the Material Properties of the Triangular Fibrocartilage Complex

Abstract

Purpose: The triangular fibrocartilage complex (TFCC) serves to stabilize the distal radioulnar joint, but the stress distribution within the TFCC under dynamic loading is unknown. Finite element analysis (FEM) can be used to investigate the stress distribution, but its accuracy depends on knowing the material properties of the TFCC. The aim of this study was to evaluate the material properties of the TFCC using cadaveric specimens. Methods: We obtained 12 upper limbs (6 right and 6 left) from 6 fresh-frozen cadavers (3 women and 3 men). Average age at death was 78.3 years (range, 69–87 years). Using a dorsal approach, we dissected each component of the TFCC. We performed tensile and compressive testing with a mechanical testing machine. Young's modulus was calculated from the slope of the linear part of the stress–strain curve. Results: The Young's modulus was 7.0 ± 2.4 MPa in the volar component, 8.7 ± 2.3 MPa in the ulnar component, 5.4 ± 1.7 MPa in the dorsal component, 6.1 ± 3.3 MPa in the fibers of the fovea, and 8.1 ± 1.2 MPa in the articular disc. Conclusions: The Young’s modulus of each component was about 5 to 9 MPa. Specimens used in this study were from elderly individuals, and care must be taken when using these values for FEM. Clinical relevance: These data will be used to perform FEM to predict the mechanical behavior of the ulnar side of the wrist and the stress distribution applied to the TFCC, the distal radioulnar joint, and the ulnar head. Key words: Biomechanical behavior, DRUJ, Mechanical property, Pathology, TFCC