Richard B. Souza1, Radu I. Bolbos1, Brad T. Wyman2, Marie Pierre Hellio2, Thomas M. Link1, Xiaojuan Li1, Sharmila Majumdar1
1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA; 2Pfizer Inc., New London, CT, USA
It is believed that cartilage loading plays a key role in the homeostasis of the cartilage biochemical environment. The objective of the current study is to determine the influence of acute mechanical loading on tibiofemoral cartilage T1rho and T2 relaxation times. Eight subjects were imaged on a 3T GE MR scanner under two conditions: unloaded, and loaded at 50% body weight. Acute loading resulted in statistically significant decreases in the medial compartment but not the lateral compartment for both T1rho and T2, suggesting that cartilage water concentration decreases and proteoglycan concentration increases.