[The application value of the magnetic resonance T2 mapping sequence in evaluating early cartilage injury of the glenohumeral joint].

Objective: To explore the quantitative value of the T2mapping sequence in evaluating the early glenohumeral joint cartilage injury. Methods: A total of 92 patients with shoulder joint pain who underwent routine sequence and T2mapping sequence scanning in General Hospital of Ningxia Medical University from March 2023 to March 2024 were retrospectively collected as a case group. The patients were classified into tendinitis group, partial tear group and full tear group according to the degree of tendon injury. Another 25 healthy subjects of the same age were selected as the control group. Two physicians divided articular cartilage into upper, middle, and lower subregions in the T2mapping sequence and measured T2 values in each subregion. The intra-observer correlation coefficient (ICC) was employed to evaluate the inter-observer and intra-observer consistency. Independent sample t test was utilized to compare the T2 values of different subregions between the two groups. One-way analysis of variance was used to compare the T2 values of different subregions among the groups, and pairwise comparison was conducted using the Bonferroni test. Spearman correlation analysis was conducted to analyze the correlation between the T2 values in different subregions of the articular cartilage and the injury degree of the supraspinatus tendon. Results: There were 44 males and 48 females in the case group, with an age range of 38 to 60 (51.4±5.8) years; there were 32 cases in the tendonitis group, 33 cases in the partial tear group, and 27 cases in the full tear group. There were 11 males and 14 females in the control group, with an age range of 40 to 54 (49.1±3.9) years. The T2 values of the upper, middle, and lower subregions of the glenohumeral articular cartilage in the case group were (37.8±4.9) ms, (39.1±5.9) ms, and (42.1±5.1) ms, respectively, all of which were significantly higher than those in the control group [(29.4±3.3) ms, (31.7±5.0) ms, and (36.3±6.2) ms, respectively] (all P<0.001). Within the supraspinatus tendon full tear group, the T2 values were (40.2±5.7) ms, (41.2±5.4) ms, and (43.4±4.1) ms, respectively, all of which exceeded those in the partial tear group [(38.2±4.3) ms, (38.9±6.5) ms, (43.1±5.1) ms, respectively], which were also higher than those in the tendonitis group [(35.0±3.2) ms, (37.7±5.0) ms, (40.1±4.5) ms, respectively] and the control group [(29.4±3.3) ms, (31.7±5.0) ms, (36.3±6.2) ms, respectively] (all P<0.001). Statistically significant differences in T2 values were observed between different subregions of articular cartilage in both the tendonitis and partial tear groups (all P<0.05); however, no significant differences were found among the upper, middle, and lower subregions in the full tear group (P=0.140). Furthermore, the T2 values in the upper, middle, and lower subregions of articular cartilage exhibited a positive correlation with the degree of supraspinatus muscle injury (r=0.693, 0.515, and 0.449, respectively, all P<0.001). Conclusions: The T2mapping sequence can quantitatively assess the degree of articular cartilage damage, and the degree of supraspinatus tendon damage and glenohumeral joint cartilage damage is positively correlated.