Akademik Veri Yönetim Sistemi
12. Anatomi Kış Günleri, Bursa, Türkiye, 29 Ocak - 01 Şubat 2025, ss.49, (Özet Bildiri)
Objective: Anatomical variations of the Musculus biceps brachii caput longum tendon can affect clinical diagnosis and surgical planning. The location of the tendon within the shoulder joint capsule and its encapsulation by a specialized synovial sheath highlight the importance of understanding its features. However, these anatomical variations may go unnoticed or lead to misdiagnoses. This study aims to determine the prevalence of bifid tendon and other variations of the Musculus biceps brachii caput longum tendon using magnetic resonance imaging (MRI).
Materials and Methods: MRI examinations of 524 shoulders from 478 patients who underwent shoulder MRI at Eskişehir Osmangazi University’s Radiology Department between September 2024 and December 2024 were retrospectively analyzed. Patients with tendon rupture were excluded, resulting in a study cohort of 473 patients and 517 MRI scans. Images were evaluated by two radiologists, and a third radiologist was consulted in cases of uncertainty. Patient age, sex, and the presence of bifid tendons or other variations were recorded.
Results: The study population consisted of 38.27% male (181/473) and 61.73% female (292/473) patients, with a mean age of 53.52 ± 14.07 years (males: 49.52 ± 15.08; females: 56.03 ± 12.79). Variations were observed in 4.86% (23/473) of patients and 4.96% (26/517) of MRI scans. Among patients with bilateral shoulder imaging, variations were found in both shoulders in 6.82% (3/44) and in one shoulder in 6.82% (3/44), representing 10.23% (9/88) of total MRIs. Variations were observed in 6.08% (11/181) of males and 4.11% (12/292) of females (p = 0.334). Among the identified variations, 4.64% (24/517) were bifid tendons, 0.19% (1/517) were triple tendons, and 0.19% (1/517) involved both a bifid tendon and an insertional variation of one tendon attaching to the coracoid process.
Conclusion: Arthroscopic evaluations have classified variations of the Musculus biceps brachii caput longum tendon into four main categories: mesotenon, adhesive tendon, supernumerary tendon, and tendon absence. While the prevalence of bifid tendons in arthroscopy is reported to be approximately 15% in the literature, this study identified a lower prevalence (~5%) using MRI. Nevertheless, the findings underscore the clinical and surgical significance of identifying anatomical variations on shoulder MRI.
Keywords: variations, caput longum, magnetic resonance imaging