2025 ISAKOS Congress in Munich, Germany

2025 ISAKOS Biennial Congress ePoster


Correlation Between MRI And Histological Analyses For Repair Tissue Of Knee Chondral Lesions Treated With Allogenic Mesenchymal Stem Cell-Based Therapy Or Microfracture In A Phase III Clinical Trial Cohort

Kazunori Shimomura, MD, PhD, Prof., Suita, Osaka JAPAN
Atsuya Watanabe, MD, PhD, Chiba, Chiba JAPAN
Akira Tsujii, MD, PhD, Suita, Osaka JAPAN
Kazutaka Kinugasa, MD, PhD, Sakai, Osaka JAPAN
Ryohei Uchida, MD, PhD, Amagasaki, Hyogo JAPAN
Yasukazu Yonetani, MD, PhD, Hirakata, Osaka JAPAN
Yoshinari Tanaka, MD, PhD, Ibaraki, Osaka JAPAN
Yukiyoshi Toritsuka, MD, PhD, Nishinomiya, Hyogo JAPAN
Norimasa Nakamura, MD, PhD, Osaka, Osaka JAPAN

Osaka University Graduate School of Medicine, Suita, Osaka, JAPAN

FDA Status Not Applicable

Summary

Biopsies of repaired cartilage tissue at the trochlear groove may carry a risk of tissue collection errors, which could impact the assessment of cartilage repair.

Abstract

MRI is widely used as a tool for evaluating repaired cartilage due to its minimally invasive and repeatable nature. On the other hand, tissue biopsy, although more invasive, can be used to directly assess the quality of the repaired tissue. We have encountered several cases where discrepancies existed between MRI and histological findings of repaired tissue, prompting us to investigate the correlation between the two in this study.

We investigated 76 patients (mean age 39.7 years) with articular cartilage injuries of the knee, who were enrolled in a phase III clinical trial (JRCT ID: jRCT1080223548). The patients were treated with either the implantation of a three-dimensional scaffold-free tissue-engineered construct generated from allogeneic synovial mesenchymal stem cells (N=37) or microfractures (N=39). MRI assessments were conducted using the MOCART 2.0 score, while histological assessments were performed using the ICRS II histological scoring system. 63 patients who could be evaluated with both MRI and histological analyses 1 year after surgery were included in this study, and the correlation between these two parameters was calculated using Spearman rank correlation test. Additionally, correlations were examined for cartilage lesions on the femoral condyle (medial or lateral) (N=33) and the trochlear groove (N=23).

A weak positive correlation was observed in all cases (r=0.32, p=0.01). A moderate positive correlation was found in the femoral condyle cases (r=0.50, p<0.01), while no correlation was observed in the trochlear groove cases (r=-0.02, p=0.94).

Previous studies have shown a correlation between the MOCART score and the ICRS II histological score. However, in the present study, no correlation was found in the trochlear groove cases. Biopsies in this study were performed arthroscopically using a tissue biopsy needle. While it was possible to insert the needle perpendicular to the repaired tissue in the femoral condyle, it was occasionally difficult to achieve this in the trochlear groove due to the patella, suggesting a potential for tissue collection errors at this site.

In conclusion, biopsy of repaired tissue at the trochlear groove should be performed and evaluated with the potential for tissue collection errors in mind.