Background:

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Knee osteoarthritis (OA) is a major cause of disability among the older adults. Few treatments are safe and effective. Moxibustion is commonly used in treating knee OA in Chinese medicine (CM). CO

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Laser moxibustion device is a substitute for traditional moxibustion

which mimics the effects of traditional moxibustion. More data are needed to support its application in knee OA.

Objective:

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The trial aims to assess the effect and safety of CO

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laser moxibustion in patients with knee osteoarthritis compared with a sham control.

Methods:

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This is a protocol for a multicenter

randomized

double-blind

placebo-controlled trial. A total of 392 participants were recruited and assigned to the CO

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laser moxibustion group and sham laser moxibustion group with a 1:1 ratio at 6 outpatient clinics in Shanghai

China. Participants in both groups received treatment at the affected knee(s) at the acupuncture point Dubi (ST 35) and an Ashi point. There were 3 sessions per week for 4 weeks

and an additional 20-week follow-up. Primary outcomes were changes in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scores at week 4. Secondary outcomes were WOMAC function score

stiffness score and overall score

VAS pain

Short-Form heath survey (SF-36)

and patients' global assessment. The serum levels of cytokines involved in progress of knee OA were explored. Safety was assessed during the whole trial. Masking effectiveness was assessed by both participants and treatment providers.

Discussion:

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CO

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laser moxibustion device

designed as a substitute for CM moxibustion

is easy to use and control with no choking smoke and smell

and is a plausible method for double-blind research. This study would provide rigorous evidence for the effect and safety of CO

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laser moxibustion in treating knee OA (Trial registration No.: ISRCTN15030019).