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: A Four-Week Study Comparing Acetaminophen Extended Release and Rofecoxib in the Treatment of Osteoarthritis of the Knee

Eligibility criteria:
Inclusion Criteria:

          -  Symptomatic idiopathic osteoarthritis of the knee for a minimum of six months duration
             requiring treatment with either an analgesic or anti-inflammatory agent on a regular
             basis (greater than or equal to three days/week) for at least three months.

          -  A history of osteoarthritis of the knee characterized by pain of at least a moderate
             intensity.

          -  Demonstrated radiographic evidence of mild to moderate osteoarthritis based on the
             Kellgren and Lawrence radiographic entry criteria of grade 2 or 3 osteoarthritis.

          -  Subjects' physical ability was to be either American College of Rheumatology (ACR)
             Function Class I or II

          -  At the baseline visit, subjects must have reported a maximum pain intensity
             experienced over the previous 24 hours of at least moderate on a five-point scale of
             none(0), mild(1), moderate(2), moderately severe(3), or severe(4) in order to be
             enrolled in the study.

        Exclusion Criteria:

          -  Medical history, physical examinations, or radiographs suggestive of other types of
             arthritis, pseudogout, collagen vascular disease or fibromyalgia.

          -  Medical or psychiatric conditions that may influence absorption, metabolism, or
             excretion of the study medications or interfere with interpretation of adverse
             reactions to the study drug.

          -  History of allergy, sensitivity, contraindication or non-response to acetaminophen,
             rofecoxib, or drugs classified as NSAIDs including aspirin.

          -  Use of concomitant medications that might interfere with study drug assessments,
             including intra-articular corticosteroids.

          -  Signs of active knee inflammation, morning stiffness of greater than 30 minutes
             duration.

          -  Rheumatoid factor quantitative value greater than or equal to 40 IU/mL or a Westergren
             erythrocyte sedimentation rate greater than or equal to 40 mm/hour.

          -  ACR functional class III or IV, or unable to walk without assistive devices.

          -  Pregnancy, lactation, or expect to become pregnant within one month of study
             completion.
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