Axilla TERMINOLOGY Definitions • Fat-filled space between upper arm and lateral chest wall IMAGING ANATOMY Extent • Axilla is shaped like a pyramid • Consists of apex, base, and 4 walls Apex – Bounded by scapula, 1st rib, and mid 1/3 of clavicle – Passageway between arm and posterior triangle of neck Anterior wall – Pectoralis major and minor muscles Posterior wall – Subscapularis, teres major, and latissimus dorsi muscles Medial wall – Serratus anterior, upper 4 ribs, and intercostal spaces Lateral wall – Medial and lateral lips of bicipital groove into which anterior and posterior walls are inserted, coracobrachialis and short head biceps muscles Base – Axillary fascia, subcutaneous fat, and skin • Contents of axilla Axillary artery and vein – 90% and 10% of subjects have accessory axillary vein and artery, respectively Cords and terminal branches of brachial plexus Lymph nodes and vessels Fat • Axillary artery Continuation of subclavian artery – Termed axillary artery beyond lateral edge of 1st rib – Termed brachial artery beyond lower edge of teres major muscle Surrounded by cords and branches of brachial plexus Vein lies medial to artery Arterial branches – Thoracodorsal, lateral thoracic, subscapular, anterior and posterior circumflex humeral arteries Lateral thoracic artery seen deep to pectoralis muscles of anterior wall axilla Thoracodorsal artery seen deep to latissimus dorsi and teres major muscles of posterior wall axilla • Axillary vein Continuation of brachial vein – Tributaries correspond to branches of axillary artery and also cephalic vein • Brachial plexus Cords and terminal branches pass through axilla Lateral cord gives rise to – Median nerve – Musculocutaneous nerve: Pierces coracobrachialis to descend arm between biceps and brachialis muscles – Lateral pectoral nerve Medial cord gives rise to – Ulnar nerve – Contributes to median nerve – Medial pectoral nerve – Medial cutaneous nerves of arm and forearm Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related posts: Hand Vessels Elbow Soft Tissue Tumor Biopsy Hypoechoic Muscle Mass Hip and Pelvis Procedures Baker Cyst Stay updated, free articles. Join our Telegram channel Join Tags: Diagnostic Ultrasound Musculoskeletal Apr 9, 2020 | Posted by admin in MUSCULOSKELETAL IMAGING | Comments Off on Axilla Full access? Get Clinical Tree
Axilla TERMINOLOGY Definitions • Fat-filled space between upper arm and lateral chest wall IMAGING ANATOMY Extent • Axilla is shaped like a pyramid • Consists of apex, base, and 4 walls Apex – Bounded by scapula, 1st rib, and mid 1/3 of clavicle – Passageway between arm and posterior triangle of neck Anterior wall – Pectoralis major and minor muscles Posterior wall – Subscapularis, teres major, and latissimus dorsi muscles Medial wall – Serratus anterior, upper 4 ribs, and intercostal spaces Lateral wall – Medial and lateral lips of bicipital groove into which anterior and posterior walls are inserted, coracobrachialis and short head biceps muscles Base – Axillary fascia, subcutaneous fat, and skin • Contents of axilla Axillary artery and vein – 90% and 10% of subjects have accessory axillary vein and artery, respectively Cords and terminal branches of brachial plexus Lymph nodes and vessels Fat • Axillary artery Continuation of subclavian artery – Termed axillary artery beyond lateral edge of 1st rib – Termed brachial artery beyond lower edge of teres major muscle Surrounded by cords and branches of brachial plexus Vein lies medial to artery Arterial branches – Thoracodorsal, lateral thoracic, subscapular, anterior and posterior circumflex humeral arteries Lateral thoracic artery seen deep to pectoralis muscles of anterior wall axilla Thoracodorsal artery seen deep to latissimus dorsi and teres major muscles of posterior wall axilla • Axillary vein Continuation of brachial vein – Tributaries correspond to branches of axillary artery and also cephalic vein • Brachial plexus Cords and terminal branches pass through axilla Lateral cord gives rise to – Median nerve – Musculocutaneous nerve: Pierces coracobrachialis to descend arm between biceps and brachialis muscles – Lateral pectoral nerve Medial cord gives rise to – Ulnar nerve – Contributes to median nerve – Medial pectoral nerve – Medial cutaneous nerves of arm and forearm Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related posts: Hand Vessels Elbow Soft Tissue Tumor Biopsy Hypoechoic Muscle Mass Hip and Pelvis Procedures Baker Cyst Stay updated, free articles. Join our Telegram channel Join Tags: Diagnostic Ultrasound Musculoskeletal Apr 9, 2020 | Posted by admin in MUSCULOSKELETAL IMAGING | Comments Off on Axilla Full access? Get Clinical Tree
