Brachial fascia Brachial fascia The brachial fascia (deep fascia of the arm) is continuous with that covering the deltoideus and the pectoralis major muscle, by means of which it is attached, above, to the clavicle, acromion, and spine of the scapula; it forms a thin, loose, membranous sheath for the muscles of the arm, and sends septa between them; it is composed of fibers disposed in a circular or spiral direction, and connected together by vertical and oblique fibers. It differs in thickness at different parts, being thin over the biceps brachii, but thicker where it covers the triceps brachii, and over
Aberrant subclavian artery known as a lusorian artery. In the normal embryological development of the aortic arches, the right dorsal aorta regresses caudal to the origin of the 7th intersegmental artery which gives rise to the right subclavian artery. In formation of an aberrant right subclavian artery, the regression occurs instead between the 7th intersegmental artery and the right common carotid so that the right subclavian artery is then connected to the left dorsal aorta via the part of the right dorsal aorta which normally regresses. During growth, the origin of the right subclavian artery migrates until it is just distal to that