Analysis of the correlation between morphological classification of the middle glenohumeral ligament and subscapularis tears

The purpose of this study was to evaluate the correlation between the morphological classification of the middle glenohumeral ligament (MGHL) and subscapularis tears and to evaluate whether surgical release of the MGHL is warranted in patients with subscapularis tears. A retrospective analysis was performed on the surgical videos of shoulder arthroscopic rotator cuff repair surgeries conducted by the same surgeon from September 2020 to September 2021. The MGHL was classified morphologically into two types: overall classification and lateral insertion classification, and the occurrence of subscapularis tears was recorded for each type. The chi-square test was used to analyze the differences in the number of subscapularis tears among the classification groups. Out of 122 patients, 44 (36.07%) were male and 78 (63.93%) were female, with an average age of 55.03 ± 7.35 years. According to the overall classification of MGHL, there were 54 cases of Type I (44.26%), 32 cases of Type II (26.23%), 28 cases of Type III (22.95%), 2 cases of Type IV (1.64%), and 6 cases of Type V (4.92%). For the lateral insertion classification of MGHL, there were 53 cases of Type A (43.44%) and 69 cases of Type B (69%). There was no statistically significant difference in the number of subscapularis tears among the classification groups . This retrospective study found no correlation between the morphological classification of MGHL and subscapularis tears. For patients with rotator cuff tears who do not have frozen shoulder, caution should be exercised when performing release of the MGHL.