Broken upper arm bone. Coloured Xray of a fracture (yellow) of the upper arm bone (humerus). The neck of the humerus has fractured, separating its head (upper right) from its shaft (below the head). This type of injury would require the bone to be pinned in place to heal. The humeral head connects (articulates) to the scapula (shoulder blade) to its left, forming the ballandsocket shoulder joint. Above the scapula, lies the clavicle (collar bone) that articulates with the scapula. The ribs of the chest are at left.