The axillary vein and its tributaries: anatomical variations, morphometry, and surgical implications

Precise morphometric data of the axillary vein (AV) network are essential for surgical and endovascular safety. This study aims to characterize main-trunk morphometry, formation patterns (Types A/B), tributary variations, and the lateral venous channel (LVC), providing an anatomical framework potentially relevant to surgical navigation and vascular access.

Forty formalin-fixed upper extremities from adult whole-body donors were dissected. Two independent investigators measured external venous diameters at standardized landmarks and the AV to coracoid apex distance; terminal drainage patterns were recorded during dissection. The LVC was operationally defined as a distinct longitudinal venous channel coursing along the lateral axillary wall, separate from the main AV and from the principal course of its distal communicating vein, while forming an additional distal-to-proximal venous connection within the axillary venous system.

Mean proximal AV diameter was 10.42 ± 2.06 mm; distance from the coracoid apex to the AV was 44.01 ± 13.08 mm. Male donors showed significantly larger proximal AV (p = 0.016) and subscapular vein (p = 0.033) diameters. Brachial vein termination comprised Type A (independent, 75.0%) and Type B (common trunk, 25.0%). An LVC was identified in 62.5% of specimens, most frequently showing distal communication with the lateral brachial vein and proximal termination in the AV. Cephalic vein absence was 10.0%.

The axillary venous network displays marked variability. The LVC represents a recurrent lateral axillary venous configuration with variable distal communications; in the present series, all identified channels joined the AV proximally. These findings provide a detailed anatomical framework that may assist procedural planning and recognition of venous variations during axillary interventions.