This document describes the anatomical spaces in the scapular region. It outlines the boundaries and contents of the quadrangular and triangular intramuscular spaces, including the upper and lower triangular spaces. The quadrangular space contains the axillary nerve and posterior circumflex humeral vessels, while the upper triangular space contains the circumflex scapular artery. The radial nerve and profunda brachii artery are found in the lower triangular space.

1. Scapular region

5. Rotator cuff

6. Subscapular spaces
• Quadrangular
I.M.Spaces
• Triangular spaces

7. Quadrangular I.M.Spaces
• Boundaries
Superior
Inferior
Lateral
Medial
• Axillary nerve
• Posterior circumflex
humeral vessels
TMa
TMi
T

8. Upper triangular space
• Boundaries
Superior
Inferior
Lateral
• Circumflex
scapular artery TMa
TMi
T

9. Lower triangular space
• Boundaries
Superior
Medial
Lateral
• Radial nerve
• Profunda brachii
artery
TMa
TMi
T