Quantitative mapping of meniscus morphology using advanced imaging analysis in young patients

Sex-based differences in the meniscus have been examined, however, detailed location-specific meniscal size and MR-derived structural properties across meniscal regions are not well established. The proposed advanced imaging method allows for localized measurements of meniscus cross-sectional area (CSA) and signal intensity (SI) along the meniscal arc length in females and males. We hypothesized that females would exhibit smaller CSA values than males, when normalized to knee size, and that SI profiles would not differ between sexes. MR images of non-injured knees from 105 individuals (60 females; age 13-35 years) were analyzed to quantify CSA and SI along the medial and lateral meniscal arc lengths. Measurements were normalized to knee size to enable sex-based comparisons. Normalized lateral meniscus CSA did not differ significantly between females and males. In the medial meniscus, normalized anterior CSA was significantly smaller in females than males (0.04 mm²/mm; p < .001). No significant sex-based differences were observed in SI profiles along the arc length for either meniscus. This study demonstrates regional sex-based differences in normalized medial meniscus CSA but no differences in normalized SI for either meniscus. Given that differences of the normalized CSA were observed only in the anterior region of the medial meniscus, sex-based variations are not globally distributed across the meniscus but instead are confined to specific anatomical regions. This point underscores the importance of subregional analyses, as whole-structure analyses may exclude localized differences.