Real-Time MRI and 3D Modeling: Development and Application to Patellofemoral Pain

Principal Investigator: Gary S. Beaupré, PhD

Co-Investigators: Garry E. Gold, MD; Scott L. Delp, PhD; Thor F. Besier, PhD; Michael Fredericson, MD; and Christine E. Draper, MS

Objective: The specific objectives of this sub-contract are to correlate cartilage material properties with MRI imaging characteristics. Although beyond the scope of the present study, the long-term goal of this research is to provide physical therapists, physiatrists, and sports medicine clinicians with additional information that can be used to improve the treatment of patients with patellofemoral syndrome. In this study we will correlate MRI measures of cartilage physiology with estimates of cartilage modulus. Five mm diameter cartilage plugs will be imaged and tested. MRI will be used to acquire T2, T1rho and Sodium maps. Following the imaging protocol, cartilage modulus will be measured using a computer-controlled indentation tester. A multiple regression will be performed using average MRI values with the indentation properties for each cartilage specimen. This regression equation will allow us to map quantitative MR values to material property values in future computer-modeling studies.

Milestone

• A new web-based resource, called the Cartilage Interpolant Response Surface methods, has been developed for determining cartilage biphasic material properties from a creep indentation test.

Publication

Keenan KE, Kourtis L, Besier T, Lindsey DP, Gold GE, Delp SL, and Beaupré GS: Webbased resource for the computation of cartilage biphasic material properties with the interpolant response surface method. Trans Orthop Res Soc, 32:603, 2007.

Funding Source: NIH