Axillary Artery- Relations
First part (proximal to pectoralis minor) Anterior: Pectoralis major (clavicular part), a nerve loop connecting the medial and lateral pectoral nerves. Posterior: Medial cord of the brachial plexus, the long thoracic nerve, and the first digitations of the serratus anterior muscle. Medial: Axillary vein. Lateral: Lateral and posterior cords of the brachial plexus.