Trigger Points love to reside here, let me explain why.
Rhomboid exibility affects positioning and movement of the shoulder blade, which affects positioning and movement of the serratus anterior. This, in turn, affects the external obliques, and so on, setting up the development of a TrP cascade. Working with the trapezius, the rhomboids shrug the shoulders, and must be assessed when the trapezius is tight. The rhomboids work with the middle trapezius to pull the shoulder blades towards each other, and work with the levator scapulae to elevate the shoulder blade.
Head-forward posture with hunched shoulders. (Check spontaneously taken photos for a posture reality check.) The weight of a strap from a heavy bag, purse, or backpack carried on one shoulder can initiate and maintain these TrPs, as can repetitive or continuous overhead work. Chest surgery, especially mastectomy, can initiate these TrPs. Idiopathic scoliosis, asymmetrical or rotated pelvis, leg length inequality, and/or short upper arms can perpetuate them. For patients with heavy breasts that may contribute to symptoms, reduction mammoplasty can signi cantly reduce disability, muscle weakness, and pain in the middle and lower trapezius and the rhomboids.