An anomalous origin of the subclavian artery

George Bevier
1915 The Anatomical Record  
The subject containing this variation is that of a large Caucasian female, aged probably 40 or 45 years, with a good muscular development and no signs of emaciation. The right subclavian arises from the aortic arch distal to the left subclavian, and the right common carotid comes directly from the aortic arch in the position usually occupied by the anonyma, which is absent in this case. Hence, instead of arising from the anonyma, the a. subclavia dextra arose directly from the aortic arch, at a
more » ... e aortic arch, at a point 1 cm. distal to the origin of the normal a. subclavia sinistra. From here it took a course toward the right and cephalad, across the ventral surface of the second thoracic vertebra passing dorsal to the esophagus and trachea, and making an angle of about forty degrees with the latter. Its branches are (1) an a. vertebralis dextra which arises 4 em. from the origin of the right subclavian; (2) an a. cervicalis profunda, arising from the dorsal aspect of the subclavian 7 mm. lateral t o the vertebral; (3) an a. cervicalis ascendens coming from its cranial margin 12 mm. distal t o the vertebral; (4) an a. mammaria interna, from the caudal border directly below the ascending cervical; and (5) an a. transversalis colli, in the normal position, 18 mm. distal to the vertebral. After passing dorsal to the m. scalenus anterior the anomalous vessel follows a normal course into the axila. The truncus thyreo-cervicalus, the a. thyreoideus inferior, and the truncus costocervicalis were absent. The a. subclavia sinistra arose in the usual place, but presented abnormalities in its branches similar to those on the right side. There are no truncus thyreocervicalis, an a. thyreocervicalis 785
doi:10.1002/ar.1090091006 fatcat:e2bx2ijrvbcr7gilymmc22xmby