Acupuncture Prescription Based on Thermal-Sensitized Acupoints for the Treatment of Knee Osteoarthritis: Protocol for a Randomized Controlled Pilot Trial

Abstract

Background: Treatment options for knee osteoarthritis (KOA) remain limited. Although previous studies suggest that acupuncture can alleviate pain and functional impairment associated with KOA, there is significant variation in acupoint selection across studies and a lack of objective criteria to guide this choice. Infrared thermography (IRT) is recognized as a reliable method for identifying inflammatory regions in KOA. Our previous research revealed abnormal skin temperature at specific acupoints and surrounding areas in the lower limbs of patients with KOA, indicating potential treatment targets. However, there is still insufficient evidence to support their clinical application.

Objective: This pilot trial aims to assess the feasibility of conducting large-scale studies in the future and to provide preliminary evidence of the effects of acupuncture applied at IRT-guided thermal-sensitized acupoints (TAs) for the treatment of KOA.

Methods: This will be a randomized, controlled pilot trial with participant blinding. A total of 60 patients with KOA will be randomly allocated in a 1:1 ratio to either the TA group or the conventional acupoint group. Both groups will receive 3 acupuncture sessions per week for 4 weeks. In the TA group, acupoint selection will be based on points with abnormal skin temperature identified by IRT using real-time surface projection technology. In the conventional acupoint group, acupoint selection will follow the established prescription validated in previous studies. The primary outcome will be feasibility, assessed using a traffic light system to evaluate recruitment, retention, intervention completion, and completion of other outcome measures. Secondary outcomes will include the visual analog scale for pain, the Western Ontario and McMaster Universities Osteoarthritis Index function subscale, the credibility and expectancy questionnaire, skin temperature, and safety.

Results: The study has been approved by the ethics committee of the Third Affiliated Hospital of Beijing University of Chinese Medicine (BZYSY-2024KYKTPJ-44) and registered in the International Traditional Medicine Clinical Trial Registry. The first participant was enrolled on February 25, 2025, and a total of 30 participants had been enrolled by January 1, 2026. All enrollment and follow-up are expected to be completed by June 2026.

Conclusions: The findings of this study will provide evidence on the feasibility and preliminary clinical effects to support the future adoption of acupuncture prescriptions based on TAs for the treatment of KOA.

Trial registration: International Traditional Medicine Clinical Trial Registry ITMCTR2025000019; https://itmctr.ccebtcm.org.cn/mgt/project/view/-5870917416012215224.

International registered report identifier (irrid): DERR1-10.2196/81837.

Keywords: acupoint; acupuncture; infrared thermography; knee osteoarthritis; pilot.