• grade 0: no radiographic features of OA are present
  • grade 1: doubtful joint space narrowing (JSN) and possible osteophytic lipping
  • grade 2: definite osteophytes and possible JSN on anteroposterior weight-bearing radiograph
  • grade 3: multiple osteophytes, definite JSN, sclerosis, possible bony deformity
  • grade 4: large osteophytes