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 Two-Arm Study Comparing the Analgesic Efficacy and Safety of Tramadol HCl Once-a-Day Versus Placebo for the Treatment of Pain Due to Osteoarthritis

Eligibility criteria:
Inclusion Criteria for Open-Label phase:

          1. Males or females

          2. Must be between the ages of 40-80

          3. Must meet the American College of Rheumatology (ACR) Clinical Classification Criteria
             for Osteoarthritis of the Knee:

               -  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 five years prior to entry into the study

          4. Must have a history of exposure to treatment (for pain due to osteoarthritis (OA) of
             the knee) with Non-steroidal anti-inflammatory drugs (NSAIDs), COX II inhibitors or
             tramadol.

          5. Must be taking one of the above medications on a regular basis in the 30 days prior to
             Visit 2 (S0).

          6. Must meet the following criteria for severity of pain at Visit 2 (Day S0):

               -  Have a score of ≥ 4 on the 11-point Numerical Rating Scale (PI-NRS; range: 0-10)

               -  Have a total increase of ≥ 2 points on the 11-point Numerical Rating Scale
                  (range: 0-10) compared to the rating at Visit 1 (Day SX)

          7. Must have a erythrocyte sedimentation rate (ESR) < 40 mm/hr

          8. Must have oral and written language comprehension at a level sufficient to comply with
             the protocol and complete study-related materials

          9. Must have signed and dated an approved written Informed Consent form in French,
             Spanish, English or Romanian, which has also been signed and dated by the Investigator
             (unless otherwise required by the ethics committee), prior to study participation

        Exclusion Criteria for Open-Label phase:

          1. Has known rheumatoid arthritis or any other rheumatic disease

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

          3. Has a history of bursitis of the knee (target knee)

          4. Has a history of pain in the ipsilateral hip (target knee)

          5. Has had a meniscal tear in the target knee within the last 12 months

          6. Has had cartilage reconstruction procedure in the target knee

          7. Has had a therapeutic arthroscopy procedure in the target knee within the last 12
             months

          8. Has a Body Mass Index (BMI) greater than 37

          9. Has had a major illness, requiring hospitalisation during the 3 months before
             commencement of the screening period

         10. Is unwilling to stop taking pain medication other than the study medication (for
             arthritis or other types of pain) or is unwilling to stop taking other medications for
             the treatment of OA

         11. Has previously failed treatment with tramadol or discontinued treatment with tramadol
             due to adverse events

         12. Has been taking other opioids (e.g. codeine, oxycodone, hydromorphone, etc.) for
             treatment of OA or other chronic conditions

         13. Has received Corticosteroid Injections in the target knee within the last 3 months or
             Viscous injections in the target knee within the last 6 months

         14. Has had treatment within the last 3 weeks with any of the following medications:
             monoamine oxidase inhibitors; tricyclic antidepressants and other tricyclic compounds
             (e.g. cyclobenzaprine, promethazine); neuroleptics; selective serotonin reuptake
             inhibitors; serotonin-norepinephrine reuptake inhibitors or any other drug that
             reduces seizure threshold

         15. Has had treatment with another investigational agent within the last 30 days

         16. Has a history of seizure disorder other than Infantile Febrile Seizures

         17. Has a previous or current opioid dependency

         18. Has a bowel disease causing malabsorption

         19. Is pregnant, lactating or of childbearing potential and is unwilling to utilise a
             medically approved method of contraception during participation in this clinical trial

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

         21. Has significant renal disease (defined as creatinine clearance <30 mL/min

         22. Has a history of current or past substance abuse or dependence, other than nicotine

         23. Has a known and documented allergy to tramadol or any structurally similar drugs (e.g.
             opiates)

         24. Has a known and documented allergy to acetaminophen or any structurally similar drugs

         25. Has any other condition that, in the opinion of the Investigators, would adversely
             affect the patient's ability to complete the study or its measures.

        Inclusion criteria for the double-blinded phase:

          -  Patients must continue to meet the open-label eligibility criteria and

          -  Must have a score of ≥ 4 on the Numerical Rating Scale (NRS) with a total increase of
             ≥ 2 points on the NRS compared to Visit 3(Day R14) and

          -  Must not have taken any of the prohibited medications during the Open-label Phase.

        Exclusion criteria for the double-blinded phase:

          -  Patient Request

          -  Adverse Events that contraindicate further administration of the study medication

          -  Any other situation where in the opinion of the Investigator continued participation
             in the study would not be in the patient's best interest.
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 80 Years

Eligibility (NLI label): Entailment