A scapula fracture is an uncommon injury. The scapula, or shoulder blade, is a wide, flat bone that sits behind the rib cage. The scapula connects to the clavicle (collar bone) in the front of the body, and to the humerus (arm bone) at the side. Part of the scapula is lined with cartilage (the glenoid) and forms the socket of the ball-and-socket shoulder joint.
Source:Verywell health