AO classification of clavicle fractures

The AO classification of clavicular fractures along with the Neer classification system is one of the more frequently used classification systems when assessing distal clavicular fractures.

Classification

The classification system, broken into three categories focuses on the displacement and pattern of the fracture and the integrity of the coracoclavicular ligaments.

Type A

A1 when the fracture is extra-articular. A2 when the fracture is intra-articular

Type B

B1 when the fracture is extra-articular. B2 when the fracture is comminuted

  • non-operative or operative treatment can be recommended 
  • fracture is displaced
  • the coracoclavicular ligament is intact 
Type C

C1 when the fracture is extra-articular. C2 when the fracture is intra-articular

  • operative treatment is be recommended 
  • fracture is displaced
  • coracoclavicular ligament is torn