The ultimate goal of this work is to produce an arthroscopic probe allowing a minimally invasive and non-destructive method for diagnosing early stages of degeneration of articular cartilage (AC). The probe is based on the fact that healthy AC is electromechanically coupled, i.e., electrically stimulating cartilage produces a mechanical signal. A properly designed probe could use this phenomenon to quantify and map focal lesions in AC. Because the early, biochemical changes due to osteoarthritis (OA) could be reversible, this probe could substantially improve the options available for treatment. Improving probe prototypes, however, requires the ability to simulate them. The Phase I goal is to produce a finite element package able to simulate the electromechanical response of the AC. This prototype software tool will predict the measured surface stress and surface potential, as well as internal fields, resulting from current stimulation in a two-dimensional, inhomogeneous, isotropic, linear model. Previous, simplified simulations indicated probe feasibility and gave design constraints. Successful completion of Phase I would demonstrate the feasibility of, and provide groundwork for, the Phase II task: simulating the detailed three-dimensional joint / probe system; material anisotropy; and coupling to the surrounding fluids, bone, and to the probe itself.
| Frank, E; Evans, R; Lee, C et al. (2004) Quantitative electrical impedance analysis of cartilage degradation. Biorheology 41:195-202 |
