From MRI-defined bone marrow lesions to pain, structural progression, and subchondral remodeling in knee...

To characterize the publication landscape, intellectual structure, thematic evolution, and emerging clinical, mechanistic, and translational directions of magnetic resonance imaging (MRI)-defined bone marrow lesion (BML) research in knee osteoarthritis.

Web of Science Core Collection, Scopus, and PubMed were searched using core concepts related to knee osteoarthritis, MRI, and BMLs or bone marrow edema-like lesions. The searches initially identified 2,452 records, of which 2,415 were exported after database-level filters. Following cross-database deduplication, eligibility assessment, and application of the prespecified publication cutoff, 726 publications constituted the final integrated corpus. Descriptive bibliometrics, collaboration-network analysis, reference co-citation analysis, keyword and MeSH mapping, temporal thematic analysis, term frequency-inverse document frequency-based document clustering, and dictionary-based bridge-theme mapping were performed. Candidate cluster solutions from k = 2 to k = 10 were evaluated using within-cluster sum of squares, silhouette width, gap statistics, and repeated-subsample stability.

Publication activity increased substantially from 1996 through 2025, with the partial 2026 count reflecting publications available by June 1. Osteoarthritis and Cartilage was the leading journal, and the United States, Australia, Germany, China, and the United Kingdom were the major contributing countries. The knowledge base was anchored by studies of whole-joint MRI assessment, BML-related pain, structural progression, and imaging-pathology interpretation. Six exploratory text-derived research domains were identified: post-traumatic and surgical BML outcomes; community-based structural and risk correlates; subchondral biology, biomarkers, and mechanisms; longitudinal whole-joint progression and symptoms; pharmacologic, biologic, and interventional treatment; and MRI quantification and methodological validation. No single diagnostic identified a uniquely optimal cluster number; the six-domain solution was retained as an interpretable intermediate-granularity representation with moderate resampling stability. Exclusion of the 28 publications dated 2026 did not materially alter the publication trajectory, leading recent terms, or temporal-theme prevalence.

MRI-defined BML research in knee osteoarthritis has developed into a multidisciplinary field connecting imaging phenotypes with symptoms, structural progression, subchondral remodeling, biomechanics, inflammation, and treatment-oriented investigation. Future studies should integrate longitudinal lesion trajectories, quantitative imaging, adjacent joint pathology, biomechanical measures, biological markers, and pain phenotyping to clarify clinically meaningful BML subtypes and their therapeutic implications.