Third most common # in the elderly and 2nd most common in the upper limb. It is twice as common in females due to osteopenia problems:
These are injuries of the joint between the collar bone and the acromion (a projection of the scapula bone above the shoulder). It can produce a bulge on the top of the shoulder due to prominent bone. Usually treated non-operatively it may need fixation depending on the patient and injury characteristics. Treatment involves reducing the joint back to its position and using a fixation device to hold it in place.