To investigate the effect of dichloride on pain control of knee osteoarthritis and the relationship between pain relief and medicine adherence. To evaluate the pain relief rate of patients with different initial pain.

Inclusion Criteria:

• According to the OA diagnostic criteria of knee joint, the side with higher WOMAC score is defined as observing knee joint for patients with both knees conforming to OA diagnostic criteria.

  1. Repeated knee pain in the past month
  2. X-ray showed narrowing of articular space, subchondral sclerosis and/or cystic degeneration, and formation of osteophyte at articular margin.
  3. Joint fluid (> 2 times) is cool and sticky, WBC < 2000/ml
  4. Age over 40
  5. Morning stiffness less than 30 minutes
  6. Bone fricative (sensation) during exercise According to 1+2 or 1+3+5+6 or 1+4+5+6, OA of knee joint can be diagnosed.
  7. The informed consent has been signed

Exclusion Criteria:

• (1) Joint pain caused by other causes (infection, hip, lumbar and other diseases) (2) Secondary arthritis (rheumatoid arthritis, ankylosing spondylitis, etc.) (3) Severe internal medical complications and other inability to participate in the research (4) Pain in other parts exceeds joint pain (5) Contraindications to diclofenac use: active peptic ulcer/allergy/induced asthma (6) Assessment may not complete the study