T1rho and T2 mapping of ankle cartilage of female and male ballet dancers

Abstract

Background Since ballet dancers begin their training before skeletal maturity, accurate and non-invasive identification of cartilage diseases is clinically important. Angle-dependent analysis of T1rho and T2 sequences can be useful for quantification of the composition of cartilage. Purpose To investigate the angle-dependent T1rho and T2 profiles of ankle cartilage in non-dancers and dancers. Material and Methods Ten female non-dancers, ten female dancers, and 9 male dancers were evaluated using T1rho and T2 mapping sequences. Manual segmentation of talar and tibial cartilage on these images was performed by two radiologists. Inter- and intra-rater reliabilities were calculated using intraclass correlation coefficients (ICCs) and Bland–Altman analysis. Mean thickness and volume of cartilage were estimated. Angle-dependent relaxation time profiles of talar and tibial cartilage were created. Results ICCs of the number of segmented pixels were poor to excellent. Bland–Altman plots indicated that differences were associated with segment sizes. Segmented cartilage on T1rho demonstrated larger thickness and volume than those on T2 in all populations. Male dancers showed larger cartilage thickness and volume than female dancers and non-dancers. Each cartilage demonstrated angular-dependent T1rho and T2 profiles. Minimal T1rho and T2 values were observed at approximately 180°–200°; higher values were seen at the angle closer to the magic angle. Minimal T2 value of talar cartilage of dancers was larger than that of non-dancers. Conclusion In this small cohort study, regional and sex variations of ankle cartilage T1rho and T2 values in dancers and non-dancers were demonstrated using an angle-dependent approach.

Accuracy of MRI-Based Talar Cartilage Thickness Measurement and Talus Bone and Cartilage Modeling: Comparison with Ground-Truth Laser Scan Measurements

“…Ankle MRI allows noninvasive evaluation of macroscopic and ultrastructure composition/organization cartilage changes. 10,11 Quantitative MRI such as T2, 10-13 T2*, 14 T1rho, 15 dGEMRIC, 11,16 sodium, 17 and gagCEST 18 mapping provide compositional information about cartilage tissue health and repair tissue quality, 17,19,20 while morphological sequences provide information about macroscopic characteristics such as synovitis, chondral/osteochondral lesions, subchondral bone cysts, and bone marrow edema. 10,11,21…”

Ankle Joint MRI—Comparison of Image Quality and Effect of Sports-Related Stress

“…Spannow et al [23] also showed a sex-specific difference in male and female adolescents by ultrasound examination in 2010. Regional and gender variations of ankle cartilage characteristics were found in dancers and non-dancers, with male dancers showing larger cartilage thickness than female dancers and non-dancers [24]. Furthermore, when examining the tibial articular cartilage of the knee joint, a 13% greater cartilage volume was measured in male subjects [25], which had a substantial influence on the study results.…”

Biomechanical Effects of Chronic Ankle Instability on the Talar Cartilage Matrix: The Value of T1ρ Relaxation Mapping Without and With Mechanical Loading

“…23 It must be noted that the magic angle effect has a major influence on T2 and T1ρ relaxation in articular cartilage so that relaxometric data strongly depend on fiber orientation and anisotropy. 37,38 However, this effect is less pronounced for T1ρ than for T2 relaxation. 37 While the sensitivity to fiber anisotropy benefits the detection of cartilage degeneration, which is usually associated with a loss of anisotropy, the sensitivity to fiber orientation may encumber studies with comparative relaxometric measurements, for example, longitudinal studies.…”

“…A T1ρ protocol was chosen for this relaxometric study since in a previous work on comparative T2 and T1ρ mapping of the patellofemoral cartilage with in situ loading, T1ρ could be more reproducibly measured 23 . It must be noted that the magic angle effect has a major influence on T2 and T1ρ relaxation in articular cartilage so that relaxometric data strongly depend on fiber orientation and anisotropy 37,38 . However, this effect is less pronounced for T1ρ than for T2 relaxation 37 .…”