[Muscles} Lateral/posterior wall of axilla

Question 1

Subscapularis

Answer 1

O: sub scapular fossa
Ins: lesser tubercle of humerus
Inn: lower and upper subscapular nerve
Bs: subscapular artery
Action: medial rotator and ADDuctor of arm at GHJ

Question 2

Latissimus dorsi

Answer 2

O: Spinous processes of T6-T12, interspinous ligaments, thoracolumbar fascia to lumbar spinous processes L1-L5, interspinous ligaments, iliac crest, lower ribs 3-4
Ins: floor intertubercular groove (sulcus) of the humerus
Inn: thoracodorsal nerve
Bs: thoracodorsal artery
Action: Medial rotator, Adductor, and extensor of arm at GHJ

Question 3

Triceps brachii long head

Answer 3

O: infraglenoid tubercle of scapula
Ins: olecranon of the ulna via the common tendon
Inn: radial nerve
Bs: Deep brachial artery
Action: extends arm at GHJ, extends forearm at elbow