Mapping the Translational Research Structure of Photobiomodulation in Osteoarthritis: A Bibliometric Analysis

Background: Osteoarthritis (OA) is a complex whole-joint disease imparting a substantial global socioeconomic burden. Photobiomodulation (PBM) has attracted increasing research interest as a non-pharmacological intervention for OA, but the intellectual structure and developmental trajectory of this research field remain incompletely understood. Objective: This study systematically mapped the intellectual landscape, research hotspots, thematic structure, and translational characteristics of PBM research in OA using bibliometric methods. Methods: Bibliographic records were retrieved from the Web of Science Core Collection database. Following data cleaning, 422 publications (1988-2026) were analyzed using the bibliometrix package in R and VOSviewer software. Results: Publication output increased substantially after 2015, with a marked rise after 2020. Keyword co-occurrence analysis classified 71 core keywords into seven clusters, revealing a dual-axis knowledge structure comprising a mechanistic biology axis (inflammation, chondrocytes, oxidative stress, and cartilage) and a clinical rehabilitation axis (pain, WOMAC, exercise, and physical therapy). Overlay visualization and thematic map analyses indicated a gradual shift in research focus from symptom-oriented rehabilitation research toward mechanistic investigations and regenerative medicine-related approaches involving platelet-rich plasma and mesenchymal stem cells. Reference co-citation analysis identified two major citation clusters connected through studies related to inflammation, pain management, and rehabilitation. Conclusions: The PBM-OA literature is characterized by a translational knowledge structure integrating mechanistic biology and rehabilitation-oriented research. Notably, recent publication trends indicate increasing scholarly attention to regenerative medicine-related approaches while continuing to position PBM within exercise-centered conservative management. To strengthen the evidence base and guide future investigations, future research should prioritize protocol standardization, dose-response validation, and long-term structural outcomes.