Cerebral mechanism of Tuina on the descending pain inhibitory system in knee pain Study protocol for a randomized controlled parallel trial

Abstract

Abstract Background: Tuina, a manual therapy, is effective and safe for reducing clinical symptoms of knee osteoarthritis (KOA); however, the mechanism that influences pain through the descending pain inhibitory system in KOA is unclear. Thus, we will investigate the modulatory implications of Tuina on the rostral ventromedial medulla (RVM) and periaqueductal gray (PAG), which have critical roles in the descending pain inhibitory system in patients with KOA. Methods: This is a randomized, controlled parallel trial. Patients with KOA will be randomly assigned (1:1) to 6 weeks of health education or Tuina. Functional and structural magnetic resonance imaging, pressure pain thresholds, numerical rating scale, Hamilton Anxiety Scale, Western Ontario and McMaster Universities Osteoarthritis Index, and Hamilton Depression Scale will be conducted at the beginning and end of the experiment. We will use PAG and RVM as seeds in resting-state functional connectivity (rsFC) analysis. Adverse events will be documented and assessed throughout. The outcome evaluators and data statisticians will be blinded to the treatment group assignment to reduce the risk of bias. Discussion: Our trial will provide evidence on the effect of Tuina on rsFC in patients with KOA and identify possible relationships between rsFC changes and improvement of clinical variables, elucidating the effect of Tuina on the descending pain inhibitory system of patients with KOA. Trial registration: Chinese Clinical Trial Registry (ChiCTR2300070289). Date of registration: April 7, 2023