anatomy/scapula·Bone

Scapula

The flat, triangular bone on the upper back. It glides over the rib cage and carries the shoulder socket.

Fig. · Location in the body Left: location in the whole body. Right: close-up. Schematic, not to scale.

// Structure & location

The shoulder blade sits on the back of the upper ribs. Across its back runs a bony ridge, the spine of the scapula, ending on the outside in the acromion. At the front the coracoid process sticks out. On the side lies the shallow socket for the head of the humerus.

// Function

It is the mobile base for the arm. When you raise your arm, the shoulder blade rotates along with it, otherwise the arm couldn't get overhead. It isn't connected to the rib cage by a true joint; it is held and guided only by muscles, such as the trapezius and serratus anterior.

// For training & sport

In bench press, pull the shoulder blades together and down. That gives a stable base.
In pull-ups, rows and overhead presses the shoulder blade should be free to move, so the shoulder doesn't get pinched.

// Good to know

Because the socket is so shallow, the shoulder is the most mobile major joint but also the easiest to dislocate. It gets its stability mainly from the rotator cuff.

// Sources

last reviewed: 2026-11-14

// More from the atlas: Bones

Skull Spine Rib cage Clavicle Humerus Radius and ulna Pelvis Femur Kneecap Tibia and fibula