Classification of the AO-ASIF Group for Fractures of the Proximal Humerus

Extra-articular, Unifocal

Type of Fracture

Fracture Code

fracture tuberosity

greater tuberosity, not displaced

A1.1

greater tuberosity, displaced

A1.2

with a glenohumeral dislocation

A1.3

impacted metaphyseal

without frontal malalignment

A2.1

with varus malalignment

A2.2

with valgus malalignment

A2.3

non-impacted metaphyseal

simple, with angulation

A3.1

simple, with translation

A3.2

multifragmentary

A3.3

Extra-articular, Bifocal

Type of Fracture

Fracture Code

metaphyseal impaction

lateral and greater tuberosity

B1.1

medial and lesser tuberosity

B1.2

posterior and greater tuberosity

B1.3

without metaphyseal impaction

without rotatory displacement of the epiphyseal fragment

B2.1

with rotatory displacement of the epiphyseal fragment

B2.2

multifragmentary metaphyseal and one of the tuberosities

B2.3

with glenohumeral dislocation

vertical cervical line and greater tuberosity intact and anterior/medial dislocation

B3.1

vertical cervical line and fracture greater tuberosity and anterior/medial dislocation

B3.2

fracture lesser tuberosity and posterior dislocation

B3.3

Articular Fracture

Type of Fracture

Fracture Code

slight displacement

cephalotubercular, with valgus malalignment

C1.1

cephalotubercular, with varus malalignment

C1.2

anatomic neck

C1.3

impacted with marked displacement

cephalotubercular, with valgus malalignment

C2.1

cephalotubercular, with varus malalignment

C2.2

transcephalic and tubercular, with varus malalignment

C2.3

dislocated

anatomical neck

C3.1

anatomical neck and tuberosities

C3.2

cephalotubercular fragmentation

C3.3