A truly isolated fracture of the anatomic neck without involvement of either tuberosity is very rare and somewhat theoretical.
These fractures are fractures of the anatomic neck with a slight displacement. Although these fractures do not pass through the articular surface, they are termed “articular fractures”; the articular surface is detached from both tuberosities. Quite often, the blood supply of the humeral head is impaired and the risk of subsequent avascular necrosis (AVN) is high.
X-ray taken from Orozco R et al, (1998) Atlas of Internal Fixation. Used with kind permission.