Evaluation and comparison of cartilage repair tissue of the patella and medial femoral condyle by using morphological MRI and biochemical zonal T2 mapping

Abstract

The objective of this study was to use advanced MR techniques to evaluate and compare cartilage repair tissue after matrix-associated autologous chondrocyte transplantation (MACT) in the patella and medial femoral condyle (MFC). Thirty-four patients treated with MACT underwent 3-T MRI of the knee. Patients were treated on either patella (n = 17) or MFC (n = 17) cartilage and were matched by age and postoperative interval. For morphological evaluation, the MR observation of cartilage repair tissue (MOCART) score was used, with a 3D-True-FISP sequence. For biochemical assessment, T2 mapping was prepared by using a multiecho spin-echo approach with particular attention to the cartilage zonal structure. Statistical evaluation was done by analyses of variance. The MOCART score showed no significant differences between the patella and MFC (p > or = 0.05). With regard to biochemical T2 relaxation, higher T2 values were found throughout the MFC (p < 0.05). The zonal increase in T2 values from deep to superficial was significant for control cartilage (p < 0.001) and cartilage repair tissue (p < 0.05), with an earlier onset in the repair tissue of the patella. The assessment of cartilage repair tissue of the patella and MFC afforded comparable morphological results, whereas biochemical T2 values showed differences, possibly due to dissimilar biomechanical loading conditions.

Longitudinal analysis of MRI T2 knee cartilage laminar organization in a subset of patients from the osteoarthritis initiative

“…In recent studies of knee cartilage repair tissue by Welsch et al (13,18), the authors reported a gradual recovery of cartilage T 2 zonal variation after surgery. Furthermore, the authors reported that differences between healthy cartilage and cartilage repair tissue were most obvious within the deep cartilage layer for both the PAT and the MFC (18).…”

“…Furthermore, the authors reported that differences between healthy cartilage and cartilage repair tissue were most obvious within the deep cartilage layer for both the PAT and the MFC (18).…”

MRI Mapping for Cartilage Repair Follow-up

“…They reported an increase of T2 values over the condyle compared to the patella repair tissue. They conclude that differential maturation of the repair tissue depends on its environment [51].…”

Treatment of Knee Osteoarthritis with Autologous Expanded Bone Marrow Mesenchymal Stem Cells: 50 Cases Clinical and MRI Results at One Year Follow-Up

“…1.5 T scan able to perform a T2 mapping. Sequences for global cartilage assessment and qualitative measures of the cartilage morphology have been validated both in vitro and in vivo and are available for clinical use through 1,5T and 3T scanners [32,[43][44][45][46][47][48].…”

“…Small changes in collagen hydration and organization lead to cartilage degradation and OA early findings may be evident through T2 mapping before any standard procedure such as radiological tests [30][31][32].…”