Correlation of Knee Cartilage T2-Relaxation Values with Age, Sex, and Structure at 1.5-T MRI

Overview

This study provides reference data for T2-relaxation times in knee cartilage layers and subregions using 1.5-T MRI in adults without morphological cartilage pathology. It demonstrates significant correlations of T2-values with age and cartilage structure, while sex differences remain inconclusive. The findings support T2-mapping as a sensitive biomarker for early cartilage biochemical changes preceding morphological degeneration.

Background

Osteoarthritis (OA) is a prevalent joint disease characterized by cartilage degeneration, with early biochemical changes detectable before irreversible morphological damage occurs. MRI-derived T2-relaxation times reflect cartilage composition alterations such as proteoglycan loss and collagen disruption, serving as a promising non-invasive biomarker for early OA detection. Prior studies have shown T2 variability across cartilage layers and compartments, and associations with OA risk factors including age and obesity. However, data at 1.5-T MRI and layer-specific reference values remain limited, particularly regarding sex differences.

Data Highlights

Key Findings

• T2-relaxation times vary significantly between superficial and deep cartilage layers and between medial and lateral compartments.
• Age correlates positively with increased T2-values, indicating biochemical cartilage changes with aging.
• No consistent sex differences in T2-relaxation times were observed, despite female sex being an OA risk factor.
• Subjects with morphological cartilage changes exhibit altered T2-values compared to those with normal cartilage.
• Weight-bearing and non-weight-bearing cartilage subregions show distinct T2-relaxation profiles.

Clinical Implications

Layer- and region-specific T2-relaxation time reference values at 1.5-T MRI can aid clinicians in detecting early cartilage biochemical alterations before irreversible morphological damage occurs. This enhances early OA diagnosis and risk stratification, potentially guiding timely interventions. The lack of clear sex differences in T2-values suggests that other factors may mediate the higher OA risk in females.

Conclusion

This study establishes normative T2-relaxation time data for knee cartilage layers and subregions at 1.5-T MRI, highlighting age-related biochemical changes and differences between cartilage compartments. These findings support the utility of T2-mapping as a sensitive tool for early OA assessment and underscore the need for further research into sex-specific cartilage alterations.

References

1. References [1-33] as cited in original article