Patient case (clinical description): A 66-year-old woman comes to the office due to joint pain in the hands and periodic morning stiffness that lasts less than 15 minutes.  The pain is moderately severe and worsens with daily activity. The patient used Tylenol with minimal relief.  Past medical history is notable for hypertension and hypercholesteremia.  Physical examination shows firm nodules over the distal interphalangeal joints, bilaterally. The patient has pain in her knees as well. The knees are stiff in the morning for less than 30 minutes and become worse with climbing stairs. She has some sensation of bone friction during activity. X-ray shows narrowing of the joint space, subchondral bone sclerosis and osteophyte formation along the joints.

Patient's own account: I'm a 66-year-old woman and I went to my doctor's office because of a bloody joint pain in my hands that has been lasting for a while. The pain comes and go in the morning usually. I feel like a stiffness that last less than 15 minutes. The pain is moderately severe but it gets worse when I'm using my hands. I used Tylenol which helped a little. Apart from that, I suffer from hypertension and high cholesterol. The doctor made me notice that I have bumps around both of my hand joints. I also suffer from my knees and they are also stiff in the morning for around 30 min. It's even worse when I climb up the stairs! I also feel like my bones are rubbing against each other when I'm moving. The X-ray showed that I have narrow joint space, I have sclerosis, and abnormal growths of bone along my joints.

Clinical trial: A Comparison of the Analgesic Efficacy and Safety of Once Daily Tramadol OAD Tablets to Twice Daily Tramadol BID for the Treatment of Osteoarthritis of the Knee (Extension Protocol) and Open Label Safety Follow-Up

Eligibility criteria:
Inclusion Criteria:

          1. Male or Female patients between the ages of 40-75 with a diagnosis of Osteoarthritis
             of the knee consistent with the ACR Clinical Classification Criteria for Arthritis of
             the Knee (Altman, R. et al., 1991):

               -  Current knee pain,

               -  Less than 30 minutes of morning stiffness with or without crepitus on active
                  motion.

               -  Confirmation either by arthroscopy or radiologist's report (X-rays showing
                  osteophytes, joint space narrowing or subchondral bone sclerosis {eburnation})
                  within one year prior to entry into the study.

          2. ESR < 40 mm/hour

          3. WOMAC Pain Subscales total score of more than or equal to 150 mm at baseline.

          4. Oral and written language comprehension at a level sufficient to comply with the
             protocol and complete study-related materials.

          5. The Patient has signed and dated the REB approved, written, informed consent prior to
             study participation.

        Exclusion Criteria:

          1. Known rheumatoid arthritis or any other rheumatoid disease.

          2. Secondary arthritis, i.e. any of the following: septic arthritis; inflammatory joint
             disease; gout; pseudogout; Paget's disease; joint fracture; acromegaly; fibromyalgia;
             Wilson's disease; Ochronosis; Haemochromatosis; Osteochondromatosis; heritable
             arthritic disorders; or collagen gene mutations.

          3. Obesity Class II (BMI more than or equal to 35) (NIH, 2000)

          4. Major illness requiring hospitalization during the 3 months before commencement of the
             screening period.

          5. Unwillingness to cease taking medication other than the study medication for arthritic
             pain, any other concomitant pain, or OA medications.

          6. Patients who have previously failed tramadol HCl therapy or those who discontinued
             tramadol HCl due to adverse events.

          7. Patients who are taking or within the last 3 weeks have taken the following
             medications: monoamine oxidase inhibitors; tricyclic antidepressants and other
             tricyclic compounds (e.g. cyclobenzaprine, promethazine); neuroleptics; selective
             serotonin reuptake inhibitors; or other drugs which reduce seizure threshold.

          8. Patients who are taking or have taken another investigational agent within the last 30
             days.

          9. Patients with a history of seizure disorder other than Infantile Febrile Seizures.

         10. Patients who are opioid dependent.

         11. Patients with bowel disease causing malabsorption.

         12. Patients who are pregnant or lactating or patients of child-bearing potential who are
             unwilling to utilize a medically approved method of contraception during participation
             in this clinical trial.

         13. Patients with significant liver disease, defined as active hepatitis or elevated liver
             enzymes >3 times the upper boundary of the normal range.

         14. Patients with significant renal disease, defined as creatinine clearance <30 mL/min as
             estimated by the method of Levey et al., 1999.

         15. Current substance abuse or dependence, other than nicotine.

         16. Allergy or adverse reaction to tramadol or any structurally similar drugs e.g.
             opiates.

         17. Any other condition that, in the opinion of the investigators, would adversely affect
             the patient's ability to complete the study or its measures.
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.
Subject must be at most 75 Years

Eligibility (NLI label): Entailment