T1ρ andT2 relaxation time constants have been proposed to probe biochemical changes in osteoarthritic cartilage. This study aimed to evaluate the spatial correlation and distribution ofT1ρ andT2 values in osteoarthritic cartilage. Ten patients with osteoarthritis (OA) and 10 controls were studied at 3T. The spatial correlation ofT1ρ andT2 values was investigated usingZ-scores. The spatial variation ofT1ρ andT2 values in patellar cartilage was studied in different cartilage layers. The distribution of these relaxation time constants was measured using texture analysis parameters based on gray-level co-occurrence matrices (GLCM). The meanZ-scores forT1ρ andT2 values were significantly higher in OA patients vs. controls (P< 0.05). Regional correlation coefficients ofT1ρ andT2Z-scores showed a large range in both controls and OA patients (0.2–0.7). OA patients had significantly greater GLCM contrast and entropy ofT1ρ values than controls (P< 0.05). In summary,T1ρ andT2 values are not only increased but are also more heterogeneous in osteoarthritic cartilage.T1ρ andT2 values show different spatial distributions and may provide complementary information regarding cartilage degeneration in OA. Magn Reson Med, 2009. © 2009 Wiley-Liss, Inc.