Kellgren-Lawrence Grade

Grade 0 None

0

No radiographic features of osteoarthritis

✓ Normal joint space

✓ No osteophytes

✓ No sclerosis or cysts

Grade 1 Doubtful

1

Doubtful joint space narrowing and possible osteophytic lipping

• Questionable osteophytes at joint margins

• Joint space may appear normal or minimally narrowed

• No definitive OA changes

Grade 2 Minimal

2

Definite osteophytes and possible joint space narrowing

• Definite osteophytes present

• Possible joint space narrowing

• Mild sclerosis may be present

Grade 3 Moderate

3

Multiple osteophytes, definite joint space narrowing, sclerosis, possible deformity

• Multiple moderate osteophytes

• Definite narrowing of joint space (>50% loss)

• Subchondral sclerosis and possible bone deformity

Grade 4 Severe

4

Large osteophytes, marked joint space narrowing, severe sclerosis, definite deformity

• Large osteophytes throughout joint

• Marked narrowing or bone-on-bone contact

• Severe sclerosis, cysts, and definite bony deformity