Abstract

Purpose: To evaluate adiabatic T₁ρ and T₂ρ of articular cartilage in symptomatic osteoarthritis (OA) patients and asymptomatic volunteers, and to determine their association with magnetic resonance imaging (MRI)‐based structural abnormalities in cartilage and bone.

Materials and Methods: A total of 24 subjects (age range: 50–68 years; 12 female) were enrolled, including 12 early OA patients and 12 volunteers with normal joint function. Patients and volunteers underwent 3T MRI. T₂ρ, adiabatic T₁ρ, and T₂ρ relaxation times of knee articular cartilage were measured. Proton density (PD)‐ and T₁‐weighted MR image series were also obtained and separately evaluated for morphological changes using the MRI OA Knee Scoring (MOAKS) system. Comparisons using the Mann–Whitney nonparametric test were performed after dividing the study participants according to physical symptoms as determined by Western Ontario and McMaster Universities (WOMAC) score or presence of cartilage lesions, bone marrow lesions, or osteophytes.

Results: Elevated adiabatic T₁ρ and T₂ρ relaxation times of articular cartilage were associated with cartilage loss (P = 0.024–0.047), physical symptoms (0.0068–0.035), and osteophytes (0.0039–0.027). Elevated adiabatic T₁ρ was also associated with bone marrow lesions (0.033).

Conclusion: Preliminary data suggest that elevated adiabatic T₁ρ and T₂ρ of cartilage are associated with morphological abnormalities of cartilage and bone, and thus may be applicable for in vivo OA research and diagnostics.