Study on efficacy and safety of Tong-luo Qu-tong plaster treatment for knee osteoarthritis: study protocol for a randomized, double-blind, parallel positive controlled, multi-center clinical trial

BACKGROUND: Knee osteoarthritis (KOA) is a common chronic musculoskeletal disorder that seriously affects quality of life. Patients with KOA frequently develop one or more of the following typical symptoms: joint pain, stiffness, joint friction noise and impaired functionality. Traditional Chinese medicine (TCM) has been shown to have a superior effect and a particular advantage in the treatment of KOA; among TCM, the Tong-luo Qu-tong plaster is the convenient and most commonly used method in China to improve symptoms including pain, stiffness and limited mobility in patients with KOA, as it causes few adverse effects. But there is a lack of high-quality clinical evidences to support the therapeutic effect that Chinese adhesive plaster can have in relieving pain and stiffness. The purpose of this study will be to evaluate the efficacy and safety of Tong-luo Qu-tong plaster in patients with KOA. METHODS/DESIGN: This study will be a randomized, double-blind, parallel positive controlled, multi-center clinical trial, a non-inferiority trial design was adopted. A total of 2000 participants older than 40 years, with KOA, will be randomly allocated into an experimental group (n = 1500) and a control group (n = 500). All participants will receive a conventional conservative treatment lasting for 14 days as two courses, once daily. Tong-luo Qu-tong plaster will be administered externally to participants in the experimental group, while the control group will receive a Qi-zheng Xiao-tong plaster. The outcome of the total Western Ontario and McMaster Universities Arthritis Index scores, TCM syndrome quantitative score and visual analog scale scores will be measured during the assessment visits (baseline and 1-week and 2-week follow up). In addition, adverse events related to clinical symptoms and signs and results of laboratory tests will be documented during the clinical trials. DISCUSSION: This study will provide reliable evidence of the effectiveness and safety of Tong-luo Qutong plaster in patients with KOA. If the results are favorable, it is expected that the patients with KOA will benefit from this study, many patients may have a good alternative treatment for KOA. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT03309501. Registered on 8 November 2017. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13063-019-3481-6) contains supplementary material, which is available to authorized users.