A fiber-based device for testing mechanical properties of cartilage is presented within this study. The measurement principle is based on stepwise indentation into the tissue and observing of corresponding relaxation of the stress. The indenter tip is constituted of a cleaved optical fiber that includes a fiber Bragg grating which is used as the force sensor. Stress relaxation measurements at 25 different positions on a healthy bovine cartilage sample were performed to assess the behavior of healthy cartilage. For each indentation step a good agreement was found with a viscoelastic model that included two time constants. The model parameters showed low variability and a clear dependence with indentation depth. The parameters can be used as reference values for discriminating healthy and degenerated cartilage.

Date Published: 23 April 2017
PDF: 4 pages
Proc. SPIE 10323, 25th International Conference on Optical Fiber Sensors, 103230G (23 April 2017); doi: 10.1117/12.2263453

Published in SPIE Proceedings Vol. 10323:
25th International Conference on Optical Fiber Sensors
Youngjoo Chung; Wei Jin; Byoungho Lee; John Canning; Kentaro Nakamura; Libo Yuan, Editor(s)