Table 1

Radiographical grading scales

GradeKellgren-LawrenceAhlbäck
1Doubtful joint space narrowing and osteophyte formationJoint space narrowing (<3 mm)
2Definite osteophyte formation with possible joint space narrowingJoint space obliteration
3Multiple osteophytes, definite joint space narrowing, sclerosis and possible bony deformityMinor bone attrition (0–5 mm)
4Large osteophytes, marked joint space narrowing, severe sclerosis and definite bony deformitySevere bone attrition (>10 mm)