H Hamada1, T Nishii2, S Tamura3, H Tanaka4, T Wakayama5, N Sugano3. 1. Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan. 2. Department of Orthopaedic Medical Engineering, Osaka University Graduate School of Medicine, Osaka, Japan. Electronic address: nishii@rf7.so-net.ne.jp. 3. Department of Orthopaedic Medical Engineering, Osaka University Graduate School of Medicine, Osaka, Japan. 4. Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, Osaka, Japan. 5. GE Healthcare Applied Science Laboratory, Asia Pacific, Tokyo, Japan.
Abstract
OBJECTIVE: To compare changes in T1rho and T2 values of the femoral cartilage in porcine knee joints under staged loading and unloading conditions. DESIGN: Sixteen porcine knee joints with intact capsules and surrounding muscle were imaged using a custom-made pressure device and 3.0 T magnetic resonance imaging. Sagittal T1rho and T2 images were obtained for the lateral and medial condyles under the following compression loads: none (Load 0), 140 N (Load 140), 300 N (Load 300), and no compression after decompression (Post-load). The percentage changes of cartilage T1rho and T2 values under each loading condition from those at Load 0 were calculated for weight-bearing overall and eight subdivided regions of interest (ROIs) in both femoral condyles. The actual contact pressure under Load 140 and Load 300 was measured using pressure-sensitive film. RESULTS: For the overall ROI, the mean decreases of T1rho and T2 values were 4.4% and 5.1% under Load 140% and 10.9% and 10.6% under Load 300 in the medial condyle and were 5.2% and 4.0% under Load 140% and 10.6% and 6.0% under Load 300 in the lateral condyle. In the medial condyle, the actual contact pressure correlated highly with percentage changes in T1rho (r = -0.84, P < 0.01) and T2 (r = -0.79, P < 0.01), but those correlations were relatively low in the lateral condyle. CONCLUSION: Although there were side-dependent variations in the correlations with actual pressure, cartilage T1rho and T2 showed similarly sensitive responses to applied load.
OBJECTIVE: To compare changes in T1rho and T2 values of the femoral cartilage in porcine knee joints under staged loading and unloading conditions. DESIGN: Sixteen porcine knee joints with intact capsules and surrounding muscle were imaged using a custom-made pressure device and 3.0 T magnetic resonance imaging. Sagittal T1rho and T2 images were obtained for the lateral and medial condyles under the following compression loads: none (Load 0), 140 N (Load 140), 300 N (Load 300), and no compression after decompression (Post-load). The percentage changes of cartilageT1rho and T2 values under each loading condition from those at Load 0 were calculated for weight-bearing overall and eight subdivided regions of interest (ROIs) in both femoral condyles. The actual contact pressure under Load 140 and Load 300 was measured using pressure-sensitive film. RESULTS: For the overall ROI, the mean decreases of T1rho and T2 values were 4.4% and 5.1% under Load 140% and 10.9% and 10.6% under Load 300 in the medial condyle and were 5.2% and 4.0% under Load 140% and 10.6% and 6.0% under Load 300 in the lateral condyle. In the medial condyle, the actual contact pressure correlated highly with percentage changes in T1rho (r = -0.84, P < 0.01) and T2 (r = -0.79, P < 0.01), but those correlations were relatively low in the lateral condyle. CONCLUSION: Although there were side-dependent variations in the correlations with actual pressure, cartilageT1rho and T2 showed similarly sensitive responses to applied load.
Authors: Sven Nebelung; Manuel Post; Matthias Knobe; Markus Tingart; Pieter Emans; Johannes Thüring; Christiane Kuhl; Daniel Truhn Journal: Sci Rep Date: 2019-04-11 Impact factor: 4.379
Authors: Tobias Hafner; Justus Schock; Manuel Post; Daniel Benjamin Abrar; Philipp Sewerin; Kevin Linka; Matthias Knobe; Christiane Kuhl; Daniel Truhn; Sven Nebelung Journal: Sci Rep Date: 2020-09-15 Impact factor: 4.379
Authors: Marc Sebastian Huppertz; Justus Schock; Karl Ludger Radke; Daniel Benjamin Abrar; Manuel Post; Christiane Kuhl; Daniel Truhn; Sven Nebelung Journal: Life (Basel) Date: 2021-03-05