Ultrashort echo time bi-component analysis of tibiotalar articular cartilage after long-distance running.

Abstract

To evaluate tibiotalar cartilage changes in amateur marathon runners pre- and post-marathon using 3D ultrashort echo time (UTE) bi-component analysis. Amateur runners were prospectively enrolled and underwent ankle MRI at three time points: pre-marathon, 2 days post-marathon, and 4 weeks post-marathon. UTE component analysis was used to obtain single-component values (T2*M), and bi-component values (short (T2*S) and long T2* component values (T2*L), and short T2* fractions) of cartilage. Sagittal images were analyzed by segmenting tibial and talus cartilage into 12 subregions (medial/lateral, anterior/middle/posterior). Thirty-two runners (26 men, 6 women; mean age, 39.80 ± 6.00 years) were evaluated. UTE component analysis parameters increased in most subregions after running, with T2*M increasing further at 4 weeks, while T2*S, T2*L, and short T2* fractions decreased. Repeated-measures analysis of variance (RM-ANOVA) revealed significant T2*S differences in the middle and posterior medial tibia (MTiM, MTiP), the middle medial talus (MTaM), the anterior, middle, and posterior lateral tibia (LTiA, LTiM, and LTiP), and the middle and posterior lateral talus (LTaM and LTaP) (p < 0.05). Short T2* fractions exhibited significant changes in MTiM, MTiP, MTaM, LTiM, and LTaM (RM-ANOVA, p < 0.05). MTiP, MTaP, LTiM, and LTaM showed significant T2*M changes (RM-ANOVA, p < 0.05). Only LTaM showed significant T2*L changes (Friedman's rank test, p < 0.05). The T2*S and short T2* fractions from UTE bi-component analysis may be more sensitive than T2*M, offering a promising method for detecting dynamic changes in ankle cartilage following long-distance running. Question Long-distance running causes changes in the tibiotalar articular cartilage. Can UTE component analysis of T2* monitor dynamic changes of tibiotalar articular cartilage non-invasively? Findings T2*S and short T2* fractions of UTE bi-component analysis were superior to single-component analysis in monitoring dynamic changes in ankle cartilage. Clinical relevance This study suggests that the UTE bi-component T2* analysis detects exercise-induced cartilage changes, allowing early matrix assessment in at-risk populations and supporting prevention strategies for athletes.