Localization of axillary artery on body surface and origin and classification of its branches based on CTA

Abstract

Objective To determine the localization of axillary artery on body surface through computed tomography angiography (CTA), so as to provide imaging data of axillary artery anatomy for clinical treatment. Methods The imaging data of patients undergoing CTA of head and neck in our hospital from July to November in 2020 were collected. A total of 456 sides (228 cases) were initially included, and then 197 sides were excluded due to improper body position. 3-D reconstruction was performed on the remaining 259 sides, and the distances as well as position relationship of axillary artery with clavicle, coracoid process and body surface were measured and observed. After the further exclusion of 110 sides with unlocatable axillary arteries, 149 sides were finally included; the length and inner diameter of axillary arteries were measured, and the origin and types of branches were observed and analyzed. Results The distance from the starting point of axillary artery to the perpendicular line of the posterior edge of clavicle and to the midclavicular line was 16.9±5.3 mm and 11.9±6.1 mm, respectively. The length of the vertical line of the lower edge of the coracoid process intersecting the axillary artery was 29.4±9.4 mm, and the proximal end of the third segment of the axillary artery lay below the coracoid process. In terms of the branches, the highest frequency of superior thoracic artery (ST) which branched out of the first segment of axillary artery was 49.0%; the thoracoacromial artery (TA) and lateral thoracic artery (LT) originated from the second segment, with the highest frequency of 49.7% and 47.7%, respectively; the highest frequencies of subscapularis artery (SS), anterior humeral circumflex artery (CHA) and posterior humeral circumflex artery (CHP) from the third segment were 71.1%, 11.4% and 64.4, respectively. The occurrence rate of TA, SS and CHP was all 100%; although that of LT was 96.6%, it presented the most types (4 types). In addition, the occurrence rate of CHA was 12.1%, and that of deep brachial artery (DB) with single stem originated from the third segment was 37.6%. Conclusion In supine position and adduction of the upper limb, the starting point of the axillary artery and the proximal of its third segment can be localized by one fingerbreadth from the medial midclavicular line as well as posterior to the clavicle, and by two fingerbreadths below the coracoid process, respectively.

Keywords

• axillary artery
• junctional hemorrhage
• junctional tourniquet
• uted tomography angiography
• anatomy