Subscapular fossa, Supraspinous fossa, Infraspinous fossa

Anterior

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.

The depression in the scapula can be either one of four different structures; the supraspinatus fossa, the infraspinatus fossa, the subscapular fossa, or the glenoid fossa. The problem is that none of these articulate with the ulna. The bone you are probably looking for is the humerus, and it articulates with the last one I mentioned, the glenoid fossa.

subscapular