The subclavian artery is a major vessel supplying the neck and upper limbs, and significant anatomical variations are often observed in its branches. This study investigated bilateral variations in the branching of the subclavian arteries, including rare deviations such as the presence of a thyrovertebral trunk and altered origins of several branches of the subclavian arteries. The goal of this study was to contribute to the limited literature on these anomalies, which have implications for clinical practice and surgical procedures.

During routine dissection of an 87-year-old male donor, notable bilateral variations in the subclavian artery branching were identified. On the right side, the thyrovertebral trunk originated from the subclavian artery, from which the vertebral and inferior thyroid arteries originated. Additionally, a common trunk gave rise to the internal thoracic, transverse cervical, and ascending cervical arteries. On the left side, the subclavian artery gave rise to the vertebral artery, inferior thyroid artery, and costocervical trunk, as well as the common trunk for the internal thoracic, transverse cervical, and suprascapular arteries.

The findings highlight significant anatomical variations in the subclavian artery branching patterns, including the presence of a thyrovertebral trunk and the absence of a thyrocervical trunk bilaterally. These variations are clinically relevant, particularly in surgeries involving the neck and upper limbs, and should be considered to avoid complications during surgery. This study proposes the term “thoracocervical trunk” for the common root of the transverse cervical and internal thoracic arteries, which may aid in the identification of similar anomalies in future clinical practice.