Incidence of teres minor muscle atrophy in young and middle-aged populations

• Published in: JSES international 2022-05, Vol.6 (3), p.459-462
• Main Authors: Takeuchi, Yasutaka, Sugaya, Hiroyuki, Takahashi, Norimasa, Matsuki, Keisuke, Tokai, Morihito, Morioka, Takeshi, Ueda, Yusuke, Hoshika, Shota, Kawashima, Itaru
• Format: Article
• Language: English
• Subjects: Rotator cuff; Shoulder; Teres minor atrophy; Young population
• ISSN: 2666-6383; 2666-6383
• DOI: 10.1016/j.jseint.2022.01.003

Teres minor atrophy can be seen in shoulders both with and without a rotator cuff tear, even among the young population. The purpose of this study was to retrospectively investigate the incidence of teres minor atrophy in young and middle-aged patients with or without a rotator cuff tear. Patient records were reviewed to identify 10-39-year-old patients (Group Y) and 60-69-year-old patients (Group O) who underwent MRI because of shoulder disorders. The exclusion criteria were as follows: (1) prior surgeries, (2) neurological disorders in the cervical spines or shoulder girdle, (3) global atrophy of all four cuff muscles without a rotator cuff tear, (4) acute trauma, and (5) poor image quality due to artifacts. An experienced shoulder surgeon evaluated teres minor atrophy on T1-weighted oblique sagittal images. Statistical analysis was performed using the chi-square test for comparison of Groups Y and O. Group Y consisted of 528 shoulders in 520 patients, including 406 males and 114 females with a mean age of 26 years. Group O consisted of 884 shoulders in 837 patients, including 394 males and 443 females with a mean age of 65 years. Rotator cuff tears were seen in 33 shoulders (6.3 %) in Group Y, and 411 shoulders (46.5%) in Group O. Teres minor atrophy was more present in Group O (59 shoulders [6.7%]) than Group Y (11 shoulders [2.1%], P