Finger and Thumb Joint Osteoarthritis: Classification

Native radiological classification of osteoarthritis according to the Kellgren and Lawrence score.

Osteophytes (new bone formations) Joint space Sclerosis Deformation Points
none or questionable none or questionable narrowed none none 0
unique unique light light 1
large advanced light with cysts distinctly 2
cancelled strong with cyst formation 3

Interpretation

According to the Kellgren-Lawrence score, the radiological expression of osteoarthritis is divided into five grades:

  • Grade 0 = 0 points
  • Grade 1 = 1-2 points
  • Grade 2 = 3-4 points
  • Grade 3 = 5-9 points
  • Grade 4 = 10 points

Grade 1: Minor subchondral (“below the cartilage“) sclerosis, no joint space narrowing or osteophytesGrade 2: Minor joint space narrowing and incipient osteophyte formation, indicated joint surface irregularitiesGrade 3: Marked osteophyte formation, marked joint surface irregularitiesGrade 4: Marked joint space narrowing to complete destruction, deformity/necrosis of joint partners.

Classification of osteoarthritis according to Noyes/Stabler.

Stage Macroscopic-arthroscopic pathologies
1
  • (a) cartilage softening with residual resilience.
  • (b) cartilage softening with absent resilience.
2
  • (a) <50% vertical cartilage substance defect.
  • (b) > 50% vertical cartilage substance loss.
3
  • (a) Cartilage baldness with intact subchondral zone.
  • B) Cartilage baldness with damaged subchondral zone.

Classification of rhizarthrosis according to Eaton/Little.

Stage Native radiological pathologies
1 Joint splitter extension if necessary
2 Joint space narrowing, osteophytes (bone neoplasms), free joint bodies <2 mm.
3 Progressive joint narrowing, osteophytes, free joint bodies > 2 mm.
4 Additional osteoarthritis of the scaphoid (scaphoid trapezoid) joint (STT joint; joint between the scaphoid (scaphoid bone), trapezium (large polygonal bone), and the trapezoideum (small polygonal bone))/carpal arthrosis