Grades of osteoarthritis by Ahlbäck

Grading of joint osteoarthritis by Ahlbäck uses plain postero-anterior weight-bearing radiographs to assess the extent of degenerative disease as joint space narrowing and bone attrition.

Grade - Changes Description
Grade I joint space narrowing (<3mm)
Grade II joint space obliteration
Grade III minor bone attrition (0 - 5mm)
Grade IV moderate bone attrition (5 - 10mm)
Grade IV severe bone attrition (>10mm)


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