Lequesne proposed criteria for disease activity in osteoarthritis affecting the hip or knee joints. The list has not been validated but reflects suggestions in the literature.
Major Criteria:
(A) radiographic narrowing of the joint space >= 0.5 mm over a 6 month period, reflecting destructive activity
Minor Criteria:
(A) local to affected joint at a given time
(1) high level of pain and disability, inconsistent with moderate radiographic osteoarthritis
(2) several NSAIDs ineffective
(3) synovial fluid rich in non-urate calcium crystals
(B) general symptoms at a given time
(4) number of other osteoarthritic joints >= 4
(5) excess physical activity
(6) excess weight
(C) over a 6-12 month period
(7) relapses with effusions (knee) >= 2
(8) number of flare ups
(9) number of intra-articular injections >= 2
where:
• The number of flare ups required to meet the minor criteria is not stated. In the implementation I have used >= 2.
• The calcium crystals reflect evidence of chondrocalcinosis.
Lequesne does not specify the number of major and/or minor criteria needed to diagnose active osteoarthritis.
• In the implementation, I have used the presence of the major criteria and/or 3 or more minor criteria as indication of active disease.
