These fractures are unifocal extraarticular proximal humerus fractures with metaphyseal impaction, sometimes referred to as surgical neck fractures.
The distinguishing features of these fractures are a) their transmetaphyseal location at the level of the surgical neck and b) their impaction. Because of the latter, they are quite stable and are typically treated conservatively.
If stability is in doubt, fracture assessment under image intensification is helpful. The fractures can be further characterized by their direction of angulation, primarily varus or valgus.
Fracture without frontal malalignment
The fractures of this subgroup are without frontal malalignment. They may be posteriorly or anteriorly impacted. This will be shown on the axillary lateral or scapular Y view.
Fracture with varus malalignment
Fractures of this subgroup have varus malalignment. Their impaction may be purely varus or associated with apex anterior or posterior angulation.
Fracture with valgus malalignment
Fractures of this subgroup have valgus malalignment. Their impaction may be either pure valgus or associated with apex anterior or posterior angulation.