This depression is called as sub scapular fossa. Scapula is fitted on convex surface of the chest wall. That is why this surface of the scapula has got depression.
Subscapular fossa
The subscapularis muscle originates on the anterior surface of the scapula and inserts on the proximal anterior humerus. Its function is to rotate the head of the humerus medially.
Serratus anterior
Suprascapular Fossa
Serratus Anterior
Interventricular groove or Sulcus
Serratus Anterior, moves scapula forward.
The subscapularis muscle originates on the anterior surface of the scapula and inserts on the proximal anterior humerus. Its function is to rotate the head of the humerus medially.
lower trapezius, serratus anterior
Abducts scapula (moves scapula away from spinal column)
Serratus anterior
hm...if I had to take a wild guess....I would guess serratus anterior and pec minor.
Abducts scapula (moves scapula away from spinal column)
Serratus anterior and trapezius
Suprascapular Fossa
The Serratus Anterior moves the scapula forward and rotates it upward.
Serratus Anterior
The movement of the scapula is largely determined by the position of the shoulder girdle as a whole. As a "floating bone" the scapula is often at the mercy of the more fixed extremities and can be acted upon by several different muscles simultaneously. That being said, the prime mover responsible for scapular depression is the trapezius (specifically the lower fibers). Other muscles which act as stabilizers or synergists in scapular depression and eventual scapular protraction are the subscapularis, the serratus anterior and the lower fibers of latissimus dorsi.