Male Omoclavicular Triangle of the Neck

Description

Centered low in the lateral neck, the omoclavicular (supraclavicular) triangle is bounded superiorly by the inferior belly of the omohyoid, medially by the posterior border of the sternocleidomastoid, and inferiorly by the clavicle. The floor is formed by prevertebral fascia overlying the anterior scalene and middle scalene muscles, with the phrenic nerve coursing inferiorly on the anterior scalene. Deep to this interval lie the third part of the subclavian artery laterally and the subclavian vein anteroinferiorly, while the trunks of the brachial plexus pass posterolateral to the artery toward the axilla. A tight space. Clinically, this triangle is the operative corridor for supraclavicular exposure of the subclavian artery and proximal brachial plexus, where relationships to the anterior scalene and the omohyoid guide safe dissection. It is also the landmark region for evaluation of supraclavicular lymph nodes (including Virchow node on the left) and for recognizing compression patterns seen in thoracic outlet syndrome, where scalene hypertrophy or fibrous bands can narrow the interscalene space and compromise neurovascular structures. The proximity of the pleural cupola just inferior and posterior to the clavicle explains why deep needle placement in this area can precipitate pneumothorax. Use this artwork in gross anatomy and head and neck surgical anatomy courses to teach the posterior triangle subdivisions and the course of subclavian vessels, or in vascular and peripheral nerve publications illustrating supraclavicular approaches, central venous access planning, and thoracic outlet syndrome anatomy. Anatomical accuracy verified by SciePro's Medical Advisory Board.