Chondral and Osteochondral Femoral Cartilage Lesions Treated with GelrinC: Significant Improvement of Radiological Outcome Over Time and Zonal Variation of the Repair Tissue Based on T Mapping at 24 Months.

Objective: To prospectively assess the efficacy of GelrinC in the treatment of chondral and osteochondral femoral cartilage lesions using morphological (Magnetic Resonance Observation of Cartilage Repair Tissue [MOCART]) and quantitative (T-mapping) magnetic resonance imaging (MRI).

Design: This study was designed as a prospective single-arm, open label, multicenter study. Morphological magnetic resonance imaging (MRI) for MOCART assessment and T mapping was performed 1 week and 6, 12, 18, and 24 months after GelrinC implantation. Evaluation of T mapping was based on the assessment of global T indices (T of the repair tissue [RT] divided by T of healthy reference cartilage) and zonal variation.

Results: Fifty-six (20 female) patients were prospectively enrolled. The mean MOCART score significantly increased from baseline to the 24-month follow-up with 88.8 (95% CI, 85.8-91.9; < 0.001) for all lesions combined as well as 86.8 (95% CI, 83.0-90.6) for chondral lesions and 94.1 (95% CI, 68.55-100) for osteochondral lesions. Furthermore, based on T mapping, significant zonal variation of the RT was observed at 24 months ( = 0.039), which did not differ significantly from healthy reference cartilage ( = 0.6).

Conclusion: Increasing MOCART scores were observed throughout the follow-up period, indicative of maturation of the cartilage repair. Significant zonal variation of the RT at 24 months might indicate the transformation into hyaline cartilage-like RT. Slightly differing morphological outcome between chondral and osteochondral lesions, but similar global and zonal T indices at 24 months, support the potential of GelrinC as a treatment option for both lesion types.