Figure 1.

Anteroposterior radiographs providing examples of acromioclavicular osteoarthritis grades (A) 0, (B) 1, (C) 2, and (D) 3, as well as (E) distal clavicular osteolysis. The difference between grades 2 and 3 is primarily with regard to the size of the periarticular osteophytes.²⁷