Triangles of Posterior shoulder and arm

Question 1

what structures are in the quadrangular space?

Answer 1

posterior circumflex humeral artery (thicker than axillary nerve on cadaver),
axillary nerve (next to posterior circumflex humeral artery on cadaver)

Question 2

boundaries of triceps hiatus?

Answer 2

long head of triceps brachii
Short head of triceps brachii
inferior border of teres major

Question 3

structures of triceps hiatus?

Answer 3

profunda brachii artery (deep artery of arm)/deep brachial artery,
radial nerve,

Question 4

boundaries of triangular space?

Answer 4

inferior border of teres minor
superior border of teres major
medial border of long head of triceps brachii

Question 5

structures of triangular space?

Answer 5

circumflex scapular artery

Question 6

where does the suprascapular artery pass over?

Answer 6

passes over the superior transverse scapular ligament, which spans the scapular notch

Question 7

where does the suprascapular nerve pass under?

Answer 7

passes under the superior transverse scapular ligament

Question 8

Boundaries of Quadrangular space?

Answer 8

Inferior border of teres minor
superior border of teres major
lateral border of long head of triceps brachii
humerus

Question 9

where does the deep brachial artery run?

Answer 9

In between the long head and lateral head of the triceps brachii in the triceps hiatus