The Triangular Space - Podcast Version 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x The triangular space is an anatomical space located in the axilla. It allows structures to pass between the axilla and posterior scapular region. In this article, we shall look at the anatomy of the triangular space – its borders, contents and clinical correlations. Note: This area should not be confused with the triangular interval, which lies inferiorly to the triangular space, and is discussed here. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Borders The triangular space is orientated with the base laterally and apex medially. It has three borders: Lateral – medial margin of the long head of the triceps brachii. Inferior – superior margin of the teres major. Superior – inferior border of the teres minor (or subscapularis). By TeachMeSeries Ltd (2026) Fig 1The borders of the triangular space. Contents The triangular space is a passageway that allows structures to travel between the axilla and posterior scapular region. It contains the circumflex scapular artery and vein. By TeachMeSeries Ltd (2026) Fig 2The circumflex scapular artery passes through the triangular space to enter the posterior scapular region. Do you think you’re ready? Take the quiz below Pro Feature - Quiz The Triangular Space Question 1 of 2 Submitting... Skip Next Rate question: You scored 0% Skipped: 0/2 1800 More Questions Available Upgrade to TeachMeAnatomy Pro Challenge yourself with over 1800 multiple-choice questions to reinforce learning Learn More Frequent questions What is the triangular space in anatomy? The triangular space is an anatomical region located in the axilla that facilitates the passage of structures between the axilla and the posterior scapular area. This space is important for the vascular supply to the shoulder and upper limb. What are the borders of the triangular space? The triangular space is defined by three borders: laterally by the medial margin of the long head of the triceps brachii, inferiorly by the superior margin of the teres major, and superiorly by the inferior border of the teres minor or subscapularis. These borders help delineate the space and its contents. What structures pass through the triangular space? The triangular space serves as a conduit for the circumflex scapular artery and vein, allowing them to travel between the axilla and the posterior scapular region. This is crucial for the blood supply to the shoulder area. What is the clinical significance of the triangular space? The triangular space is clinically relevant as it contains important vascular structures that supply the shoulder and upper limb. Understanding its anatomy is essential for surgical approaches and diagnosing conditions related to shoulder injuries. How does the triangular space differ from the triangular interval? The triangular space is located superiorly, while the triangular interval lies inferior to it. These two spaces are distinct anatomical regions, each with different borders and contents, and should not be confused during anatomical studies. Rate This Article