Study on the effects of Curcuma longa, Piper nigrum and Camellia sinensis extract mixture on the symptoms of knee osteoarthritis: a randomized controlled trial

Study on the effects of Curcuma longa, Piper nigrum and Camellia sinensis extract mixture on the symptoms of knee osteoarthritis: a randomized controlled trial

This clinical trial study will be conducted in a double-blind phase 2-3 on 60 patients with knee osteoarthritis. Patients are randomly divided into two parallel groups. After completing the relevant questionnaires, patients will be given a herbal medicine bottle containing 60 herbal medicine capsules or placebo and its code (A or B) will be recorded in the patient's medical records.

Patients with knee osteoarthritis referring to Baghiatallah Hospital according to inclusion criteria randomly divided to herbal medicine or placebo groups. Except main investigator, non of the medical stuff, patients, data collector and who evaluate the outcome, are unaware of the medication type.

Inclusion criteria: Patients with osteoarthritis visit to Baqiyatallah Hospital in Tehran; Male or female patients aged 40 to 80 years according to the criteria of the American College of Rheumatology; Patients with Knees osteoarthritis grade 1 or 2. Exclusion criteria: Patients with history of arthroscopy, surgery, or Injection to the target knee joint within the past 6 months; History of knee replacement; Any serious systemic disease (such as secondary infections and cardiovascular, liver, and kidney diseases) or any other chronic inflammatory disease; Any history of alcohol and drug abuse

Intervention group: Patients will orally take one 500 mg capsule of the herbal mixture (containing Curcuma longa, Piper nigrum and Camellia sinensis) produced by the Medicinal Plants Research Center of Jihad Daneshghani, every 12 hours after meals for a period of 2 months. Control group: Patients will orally take one 500 mg capsule of the placebo (contains toasted flour) produced by the Medicinal Plants Research Center of Jihad Daneshghani, every 12 hours after meals for a period of 2 months.

Joint pain using Visual Analog Scale questionnaire; joint stiffness and physical activity using Western Ontario and McMaster Universities Arthritis Index questionnaire

For randomization, the block randomization method will be used. By visiting the website www.sealedenvelope.com and selecting the 'Randomization' tab, the 'Make a list' option will be clicked. After specifying the number of intervention groups, the sample size, and the block size (which is set to 4 in this study), a randomized list containing specific patient codes will be generated and used for the randomization process. A randomly generated list will be used to create a series of sequentially numbered, sealed envelopes. Each envelope will be marked with a unique patient code, and inside will be a card indicating the assigned intervention group. Following the enrollment of each eligible patient, the envelope corresponding to the next sequential code will be opened by the researcher. The patient will then be assigned to their intervention group based on the card contained within the envelope.

Letters A or B are labeled on herbal medicine or placebo cans. Other specifications on the labels are completely identical. Physician, nurse, patient, data collector and those who evaluate the outcome, are unaware of the nature and meaning of the letters A or B on the labels. Only the main investigator knows the nature of the labels. Patients are aware that they are either in the drug or in the placebo groups, but they are not aware of the type of group they are in.