Patient case (clinical description): A 47-year-old woman comes to the office complaining of pain in the calf and knee when she bends down. The pain limits her activity. Her medical history is significant for osteoarthritis, for which she uses nonsteroidal anti-inflammatory drugs (NSAIDs) for the past two years. She is living with her husband and has 3 children. She doesn't smoke but drinks alcohol occasionally. Her vital signs are normal. On physical examination, there is a small effusion in the right knee. The effusion grew a little larger and she developed a tender swelling in the popliteal fossa and calf. Both the pain and swelling worsened as she bent and straightened her knee.

Patient's own account: I'm a 47-year-old woman, married with 3 kids. I don't smoke and I drink occasionally. I went to the doctor because of pain in my calf and knee when I was bending down. This has been limiting my daily activities. I have been diagnosed with osteoarthritis for which I have taken anti-inflammatory drugs for the past 2 years. The doctor saw a small fluid buildup in my right knee. This buildup became a bit bigger and I have a swollen calf. The pain is worse when I bend and straighten my knee.

Clinical trial: An Effectiveness and Safety Study of Two Doses of Acetaminophen Extended Release Caplets in the Treatment of Osteoarthritis of the Hip or Knee

Eligibility criteria:
Inclusion Criteria:

          -  Symptomats of osteoarthritis of the hip or knee for a minimum of six months

          -  History of hip or knee pain due to osteoarthritis requiring the use of NSAIDs,
             acetaminophen, or another analgesic agent on a regular basis (>= three days per week)
             for at least three months before the screening visit

          -  History of positive therapeutic benefit with acetaminophen use for osteoarthritis pain

          -  History of osteoarthritis pain (moderate, moderately severe, or severe) of the hip or
             knee when not taking osteoarthritis analgesic medication

          -  Must have a pain level of moderate or moderately severe for 24 hours over the previous
             24 hours prior to the baseline visit, and at baseline, demonstrate a 20% or greater
             increase in the pain subscale score, relative to the score at screening

        Exclusion Criteria:

          -  History of surgery, including arthroscopy, or major trauma to the study joint in the
             previous six months before the screening visit

          -  Grade 1 or grade 4 severity of the study joint based on the Kellgren and Lawrence
             radiographic criteria

          -  Maximum osteoarthritis pain intensity of none, mild or severe experienced over the
             previous 24 hours of the baseline visit

          -  Signs of clinically important active inflammation of the study knee joint including
             redness, warmth and/or a large, bulging effusion with the loss of normal contour at
             the screening and/or baseline visits
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 40 Years old.


Eligibility (NLI label): Entailment