Fracture classification systems are an essential means by which physic
ians communicate, make treatment decisions, estimate prognosis, and re
port and compare treatment results. The qualities of an ideal classifi
cation system are reviewed. The rationale and utility, as well as the
shortcomings, of several commonly used fracture classifications are di
scussed. An overview of the AO/ASIF comprehensive classification of lo
ng bone fractures is provided.