Bony landmark · Shoulders

Infraspinous fossa

Fossa infraspinata

The infraspinous fossa is the broad hollow covering most of the back of the shoulder blade below the scapular spine. The infraspinatus takes origin from it — the largest of the muscles that rotate the arm outwards, and one of the four of the rotator cuff. Because the fossa is wide and flat and lies close to the surface, this is the part of the shoulder blade a therapist can work on most directly.